Current vitamin D quantification methods do not account for 25-hydroxyl epimers, which can falsely increase concentrations and mask actual deficiencies. Previously, we developed an ultra-high performance liquid chromatography-tandem mass spectrometry method to measure 25(OH)D3, 3-epi-25(OH)D3 and 25(OH)D2; here, we extended this method to include 3-epi-25(OH)D2. Analytes were separated using a Shimadzu UPLC with a Kinetex F5 column (100 × 2.1 mm, 2.6 μm). The mobile phase contained 0.1% formic acid in methanol and water (70:30, v/v). The internal standard, deuterated 25(OH)D3 and analytes were extracted with hexane. Detection was performed by a mass spectrometer equipped with a triple quadrupole after prior electrospray ionization. It demonstrated sufficient precision and spike recovery within and between days, with a coefficient of variation ≤15% and an error of determination ≤18%. The method exhibited linearity in the 2-100-ng/mL concentration range. The limits of quantification and limits of detection were 2 and 1 ng/mL, respectively. Extraction recoveries ranged from 70.05% to 97.13%. The matrix effect, carryover and dilution integrity were evaluated and met the FDA acceptance criteria. The stability of all metabolites in plasma was confirmed after 3 h of storage at room temperature and after three cycles of freezing at -80°C and thawing. Applying the method to clinical samples showed a high 25-hydroxyl epimer derived from vitamin D.

This systematic review (SR) highlights principles for nutrient clinical trials and explore the diverse physiological functions of vitamin D beyond its traditional role in the musculoskeletal system related to clinical study designs.

Thousands of published research articles have investigated the benefits of vitamin D (a nutrient example taken in this SR) beyond the musculoskeletal system, including the immune, pulmonary, and cardiovascular systems; pregnancy; autoimmune disorders; and cancer. They illustrated vitamin D's molecular mechanisms, interactions, and genomic and nongenomic actions.

This SR was designed to identify shortcomings in clinical study designs, statistical methods, and data interpretation that led to inconsistent findings in vitamin D-related publications. SR also highlights examples and insights into avoiding study design errors in future clinical studies, including randomized controlled clinical trials (RCTs). The SR adheres to the latest PRISMA statement, guidelines, and the PICOS process.

Inappropriate or flawed study designs were frequent in clinical trials. Major failures discussed here include too short clinical study duration, inadequate or infrequent doses, insufficient statistical power, failure to measure baseline and achieved levels, and recruiting vitamin D-sufficient participants. These design errors have led to misleading interpretations. Thus, conclusions from such studies should not be generalized or used in guidelines, recommendations, or policymaking.

Adequately powered epidemiological studies and RCTs with sufficient vitamin D and duration in individuals with vitamin D deficiency reported favorable clinical outcomes, enriching the literature, enabling to understand its physiology and mechanisms. Proper study designs with rigorous methodologies and cautious interpretation of outcomes are crucial in advancing the nutrient field. The principles discussed apply not only to vitamin D, but also other micro-nutrients and nutraceutical research. Adhering to them enhances the credibility and reliability of clinical trials, SRs, and meta-analysis outcomes. The study emphasizes the importance of focused, hypothesis-driven, well-designed, statistically powered RCTs to explore the diverse benefits of nutrients, conducted in index nutrient deficient participants, and avoidance of study design errors. Findings from such studies should be incorporated into clinical practice, policymaking, and public health guidelines, improving the health of the nation and reducing healthcare costs.

Vitamin D3's role in mineral homeostasis through its endocrine function, associated with the main circulating metabolite 25-hydroxyvitamin D3, is well characterized. However, the increasing recognition of vitamin D3's paracrine and autocrine functions-such as cell growth, immune function, and hormone regulation-necessitates examining vitamin D3 levels across different tissues post-supplementation. Hence, this review explores the biodistribution of vitamin D3 in blood and key tissues following oral supplementation in humans and animal models, highlighting the biologically active metabolite, 1,25-dihydroxyvitamin D3, and the primary clearance metabolite, 24,25-dihydroxyvitamin D3. While our findings indicate significant progress in understanding how circulating metabolite levels respond to supplementation, comprehensive insight into their tissue concentrations remains limited. The gap is particularly significant during pregnancy, a period of drastically increased vitamin D3 needs and metabolic alterations, where data remains sparse. Within the examined dosage ranges, both human and animal studies indicate that vitamin D3 and its metabolites are retained in tissues selectively. Notably, vitamin D3 concentrations in tissues show greater variability in response to administered doses. In contrast, its metabolites maintain a more consistent concentration range, albeit different among tissues, reflecting their tighter regulatory mechanisms following supplementation. These observations suggest that serum 25-hydroxyvitamin D3 levels may not adequately reflect vitamin D3 and its metabolite concentrations in different tissues. Therefore, future research should aim to generate robust human data on the tissue distribution of vitamin D3 and its principal metabolites post-supplementation. Relating this data to clinically appropriate exposure metrics will enhance our understanding of vitamin D3's cellular effects and guide refinement of clinical trial methodologies.

The autoimmune/inflammatory syndrome induced by adjuvants (ASIA) was first introduced in 2011 to provide a more precise syndromic characterization of clinical manifestations observed in patients exposed to adjuvant substances such as biopolymers and silicone, among others. The clinical spectrum of this entity is variable, ranging from local involvement to potentially fatal immune-mediated systemic involvement. The interest in ASIA has grown in recent years, reinforcing diagnostic criteria and deepening the understanding of its pathophysiological behavior. This case report highlights a distinct range of clinical symptoms, such as general symptoms, advanced-stage chronic kidney disease, persistent hypercalcemia with suppressed parathyroid hormone (PTH), bilateral nephrocalcinosis, cutaneous calcinosis, and the presence of positive autoantibodies, emphasizing the significance of understanding this condition.

Contracturing granulomatous myositis is a rare myopathy in which patients present with flexion contractures of the upper limbs in addition to slowly progressive muscle weakness and pain. Whether it represents a distinct nosological entity remains a point of discussion. We present a patient with isolated granulomatous disease of the muscle that responded very well to intravenous immunoglobulins after treatment failure of corticosteroids and methotrexate.

Calcitriol-induced hypercalcemia has been rarely reported in cases of lung cancer; however, it is frequently reported in cases of lymphoid malignancy and granulomatous disease. We present a rare case of hypercalcemia associated with squamous cell cancer of the lung with elevated calcitriol level.

A 61-year-old Caucasian female with severe hypercalcemia of 15 mg/dL, which led to a new diagnosis of metastatic lung cancer. Since the parathyroid hormone-related peptide (PTHrP) level was minimally elevated at 2.1 pmol/L, we believe excessive calcitriol production by tumor cells was the underlying mechanism for hypercalcemia. Calcitriol was significantly elevated at 130 pg/mL with a low 25-hydroxyvitamin D level of 25.9 ng/mL and suppressed PTH level of 8 pg/mL. Corticosteroids are generally used to treat calcitriol-induced hypercalcemia, but we successfully treated our patient with bisphosphonate, highlighting the further utility of bisphosphonates in hypercalcemia treatment.

We believe that the underlying cause of hypercalcemia, in this case of metastatic squamous cell lung carcinoma, was elevated calcitriol, which was likely produced by the tumor cells. In addition to PTHrP, calcitriol levels should be included in the workup for hypercalcemia in cases of lung cancer. However, the pathophysiology and prognostic significance of dysregulated calcitriol production in solid tumors remain unclear and warrant further research. Bisphosphonate may be used as a steroid-sparing therapy even in cases of calcitriol-induced hypercalcemia and warrants further investigation.

Both 25-autoimmunity and(25(OH)D: calcifediol) and its active form, 1,25-dihydroxyvitamin D (1,25(OH)2D: calcitriol), play critical roles in protecting humans from invasive pathogens, reducing risks of autoimmunity, and maintaining health. Conversely, low 25(OH)D status increases susceptibility to infections and developing autoimmunity. This systematic review examines vitamin D's mechanisms and effects on enhancing innate and acquired immunity against microbes and preventing autoimmunity. The study evaluated the quality of evidence regarding biology, physiology, and aspects of human health on vitamin D related to infections and autoimmunity in peer-reviewed journal articles published in English. The search and analyses followed PRISMA guidelines. Data strongly suggested that maintaining serum 25(OH)D concentrations of more than 50 ng/mL is associated with significant risk reduction from viral and bacterial infections, sepsis, and autoimmunity. Most adequately powered, well-designed, randomized controlled trials with sufficient duration supported substantial benefits of vitamin D. Virtually all studies that failed to conclude benefits or were ambiguous had major study design errors. Treatment of vitamin D deficiency costs less than 0.01% of the cost of investigation of worsening comorbidities associated with hypovitaminosis D. Despite cost-benefits, the prevalence of vitamin D deficiency remains high worldwide. This was clear among those who died from COVID-19 in 2020/21-most had severe vitamin D deficiency. Yet, the lack of direction from health agencies and insurance companies on using vitamin D as an adjunct therapy is astonishing. Data confirmed that keeping an individual's serum 25(OH)D concentrations above 50 ng/mL (125 nmol/L) (and above 40 ng/mL in the population) reduces risks from community outbreaks, sepsis, and autoimmune disorders. Maintaining such concentrations in 97.5% of people is achievable through daily safe sun exposure (except in countries far from the equator during winter) or taking between 5000 and 8000 IU vitamin D supplements daily (average dose, for non-obese adults, ~70 to 90 IU/kg body weight). Those with gastrointestinal malabsorption, obesity, or on medications that increase the catabolism of vitamin D and a few other specific disorders require much higher intake. This systematic review evaluates non-classical actions of vitamin D, with particular emphasis on infection and autoimmunity related to the immune system.

The majority of cases involving hypercalcemia in the setting of sarcoidosis are explained by the overproduction of calcitriol by activated macrophages. Vitamin D takes part in the regulation of granuloma formation. However, using vitamin D metabolites to assess the activity of the disease is still problematic, and its usefulness is disputable. In some cases, though, a calcium metabolism disorder could be a valuable tool (i.e. as a marker of extrathoracic sarcoidosis). Although sarcoidosis does not cause a decrease in bone mineral density, increased incidence of vertebral deformities is noted. Despite increasing knowledge about calcium homeostasis disorders in patients with sarcoidosis, there is still a need for clear guidelines regarding calcium and vitamin D supplementation in these patients.

Hypercalcemia of malignancy (HCM) is a common complication of advanced cancer. PTH-independent HCM may be mediated through different mechanisms: (1) humoral HCM, caused by the secretion of PTH-related peptide (PTHrP), (2) local osteolysis resulting from metastatic lesions, and (3) calcitriol-mediated hypercalcemia. Calcitriol-mediated HCM in patients with nonlymphomatous solid tumors is thought to be rare.

We performed a retrospective chart review from 2008 to 2017 to characterize further patients at our institution with solid tumors who had HCM with concomitant elevations in calcitriol. Patients with PTH-dependent hypercalcemia and patients with evidence of granulomatous disease were excluded, as were patients with hematologic malignancies. We hypothesized that patients with HCM and elevated calcitriol levels would respond less favorably to treatment with antiresorptive therapy compared with patients with HCM but without calcitriol elevation. We also aimed to assess mortality and determine if PTHrP and phosphorus levels correlate with calcitriol because both factors may alter calcitriol levels.

Of 101 eligible patients, calcitriol was elevated in 45 (45%). PTHrP was elevated in 76% of patients with elevated calcitriol compared with 52% of patients without calcitriol elevation. The mean PTHrP value did not differ between patients with HCM and elevated calcitriol (36.3 ± 22 pg/mL) and those without calcitriol elevation (37.4 ± 19 pg/mL). Those with elevated calcitriol levels generally did not respond completely to antiresorptive treatment (80% incomplete response rate), whereas most patients without an elevation in calcitriol responded well to antiresorptive treatment (78% response rate: P < .001). There was no significant difference in the percentage of patients with metastatic bone disease among the 2 groups (49% vs. 55%, respectively). There was no difference in mortality between the 2 groups (P = .14). A weak but significant negative correlation was found between phosphorus and calcitriol (Pearson r = -0.261, P = .016). This correlation was only significant in patients without calcitriol elevation (Pearson r = -0.4, P = .0082). Also, a significant negative correlation was found between PTHrP and phosphorus, again only in patients without calcitriol elevation.

In the setting of HCM, patients with calcitriol elevation are much less likely to respond to antiresorptive therapy than patients without calcitriol elevation. Because calcitriol elevation did not appear to be correlated with hypophosphatemia or elevated PTHrP, it would appear that calcitriol production under these conditions is autonomous, and not subject to normal physiological controls. These observations indicate that calcitriol elevations in patients with HCM have clinical significance.

Hypercalcemia with suppressed parathyroid hormone (PTH) levels is mostly due to granulomatous disease (GD) or neoplastic disease. In GD, autonomous activity of extra-renal 1α-hydroxylase enzyme is usually the underlying cause. We describe a pair of cases where hypercalcemia resulted from GD of unusual sites posing significant diagnostic challenges.

We describe 2 cases of PTH-independent hypercalcemia due to GD of the prostate gland and the stomach.

Both cases presented with marked hypercalcemia and suppressed PTH levels. Case 1 is an elderly male who presented with marked symptomatic hypercalcemia on multiple occasions. Investigations revealed elevated levels of 1,25-dihydroxyvitamin D3 and prostate-specific antigen but normal PTH-related protein. Transrectal biopsy of the prostate gland confirmed the presence of chronic granulomatous prostatitis. The patient responded very well to steroids which entirely normalized his calcium level. Case 2 is a male who presented similarly with significant hypercalcemia but had upper gastrointestinal symptoms and anemia at onset. Endoscopy and biopsy established the presence of granulomatous gastritis likely due to Crohn disease which responded to steroids resulting in normalization of calcium levels within a short span of time.

While the majority of PTH-independent hypercalcemia cases are due to GDs of lymph nodes or malignancy, our cases indicate that in uncertain cases, granulomatous processes involving unusual sites should be considered in the evaluation of hypercalcemia with suppressed PTH.

Vitamin D has traditionally been known as the "bone vitamin". However, a large body of observational data has also linked low concentrations of serum 25-hydroxyvitamin D (25[OH]D), the primary storage form of vitamin D, to an increased risk of incident cardiovascular disease (CVD) and mortality, garnering public excitement about the purported nonskeletal benefits of vitamin D. Despite this, more recent meta-analyses and randomized clinical trials have failed to find a beneficial effect of vitamin D supplements on CVD and cancer outcomes. These findings, along with the lack of consensus on optimal serum 25(OH)D concentrations, have dampened some of the initial enthusiasm for vitamin D supplements. Residual confounding or reverse causation may explain some of the discrepancy between the observational and trial results. At this time, vitamin D supplements should not be prescribed for the primary purpose of CVD prevention. Adding to this complexity is the fact that many adults take vitamin D and calcium supplements together for bone health, and there is some concern (albeit inconclusive) related to calcium use and increased CVD risk. In this light, it may be best to achieve the recommended daily allowances of calcium intake through food and reserve calcium supplementation only for those at risk for calcium intake deficiency, with the smallest dosage needed after dietary modifications have been exhausted. In this review, we discuss vitamin D and calcium supplementation and how they may affect cardiovascular health.

The aim of the study was to examine the relationship between serum calcium (Ca) levels and the prevalence of hyperuricemia (HU).The data included in this analysis were extracted from a population-based study conducted at the Xiangya Hospital Health Management Centre. Serum Ca levels were measured using the Arsenazo III method. HU was defined as the uric acid ≥416 μmol/L for male subjects, and ≥360 μmol/L for female subjects. The association between serum Ca levels and the prevalence of HU was evaluated using logistic and spline regression.The present study included a total of 6337 subjects. The overall prevalence of HU for the target population was 17.5%. Compared with the lowest quintile, the odds ratios adjusted by age, sex, body mass index, smoking, and drinking for HU were 1.51 [95% confidence interval (CI): 1.20-1.91], 1.43 (95% CI: 1.13-1.82), 2.02 (95% CI: 1.61-2.54), and 2.54 (95% CI: 2.02-3.18) for the second, third, fourth, and fifth quintiles of serum Ca levels, respectively (P for trend <.001), and a positive dose-response relationship was observed. Similar results were observed for men and women, respectively. The findings were not materially altered by the adjustment for further potential confounders.Subjects with higher serum Ca levels are subject to a higher prevalence of HU in a dose-response relationship manner.

Vitamin D has a long-established role in bone health. In the last two decades, there has been a dramatic resurgence in research interest in vitamin D due to studies that have shown its possible benefits for non-skeletal health. Underpinning the renewed interest in vitamin D was the identification of the vital role of intracrine or localized, tissue-specific, conversion of inactive pro-hormone 25-hydroxyvitamin D [25(OH)D] to active 1,25-dihydroxyvitamin D [1,25(OH)₂D]. This intracrine mechanism is the likely driving force behind vitamin D action resulting in positive effects on human health. To fully capture the effect of this localized, tissue-specific conversion to 1,25(OH)₂D, adequate 25(OH)D would be required. As such, low serum concentrations of 25(OH)D would compromise intracrine generation of 1,25(OH)₂D within target tissues. Consistent with this is the observation that all adverse human health consequences of vitamin D deficiency are associated with a low serum 25(OH)D level and not with low 1,25(OH)₂D concentrations. Thus, clinical investigators have sought to define what concentration of serum 25(OH)D constitutes adequate vitamin D status. However, since 25(OH)D is transported in serum bound primarily to vitamin D binding protein (DBP) and secondarily to albumin, is the total 25(OH)D (bound plus free) or the unbound free 25(OH)D the crucial determinant of the non-classical actions of vitamin D? While DBP-bound-25(OH)D is important for renal handling of 25(OH)D and endocrine synthesis of 1,25(OH)₂D, how does DBP impact extra-renal synthesis of 1,25(OH)₂D and subsequent 1,25(OH)₂D actions? Are their pathophysiological contexts where total 25(OH)D and free 25(OH)D would diverge in value as a marker of vitamin D status? This review aims to introduce and discuss the concept of free 25(OH)D, the molecular biology and biochemistry of vitamin D and DBP that provides the context for free 25(OH)D, and surveys in vitro, animal, and human studies taking free 25(OH)D into consideration.

Soft-tissue filler (STF) injections have been used worldwide for cosmetic reasons. In most cases, they are not approved by the United States Food and Drug Administration (FDA). Regulatory boards in Latin American countries do not allow the medical use of STF injections; however, these injections are still widely used. A case of calcitriol-mediated hypercalcemia with ectopic calcifications, chronic kidney disease, nephrolithiasis and calcinosis is presented. The reported case highlights the consequences of STF use, including calcitriol-mediated hypercalcemia secondary to granulomatous reactions years after an esthetic procedure.

An immunologic adjuvant is a substance that enhances the antigen-specific immune response preferably without triggering one on its own. Silicone, a synthetic polymer used for reconstructive and cosmetic purposes, can cause, once injected, local and/or systemic reactions and trigger manifestations of autoimmunity, occasionally leading to an overt autoimmune disease. Siliconosis, calcinosis cutis with hypercalcemia and chronic kidney disease have all been reported in association with silicone injection. Here, we describe a case of autoimmune/auto-inflammatory syndrome induced by adjuvants, calcinosis cutis and chronic kidney disease after liquid silicone multiple injections in a young man who underwent a sex reassignment surgery, followed by a review of the literature. To our knowledge, this is the first report describing the concomitance of the three clinical conditions in the same patients. The link between silicone and the immune system is not completely understood yet and requires further reports and investigations with long-term data, in order to identify the main individual and genetical risk factors predisposing to the wide spectrum of the adjuvant-induced responses.

Clinical research has recently demonstrated that vitamin D deficiency (VDD) is highly prevalent in the pediatric intensive care unit (PICU) and associated with worse clinical course. Multiple adult ICU trials have suggested that optimization of vitamin D status through high-dose supplementation may reduce mortality and improve other clinically relevant outcomes; however, there have been no trials of rapid normalization in the PICU setting. The objective of this study is to evaluate the safety and efficacy of an enteral weight-based cholecalciferol loading dose regimen in critically ill children with VDD.

The VITdAL-PICU pilot study is designed as a multicenter placebo-controlled phase II dose evaluation pilot randomized controlled trial. We aim to randomize 67 VDD critically ill children using a 2:1 randomization schema to receive loading dose enteral cholecalciferol (10,000 IU/kg, maximum of 400,000 IU) or a placebo solution. Participants, caregivers and outcome assessors will be blinded to allocation. Eligibility criteria include ICU patient, aged 37 weeks to 18 years, expected ICU length of stay more than 48 h, anticipated access to bloodwork at 7 days, and VDD (blood total 25 hydroxyvitamin D < 50 nmol/L). The primary objective is to determine whether the dosing protocol normalizes vitamin D status, defined as a blood total 25(OH)D concentration above 75 nmol/L. Secondary objectives include an examination of the safety of the dosing regimen (e.g. hypercalcemia, hypercalciuria, nephrocalcinosis), measures of vitamin D axis function (e.g. calcitriol levels, immune function), and protocol feasibility (eligibility criteria, protocol deviations, blinding).

Despite significant observational literature suggesting VDD to be a modifiable risk factor in the PICU setting, there is no robust clinical trial evidence evaluating the benefits of rapid normalization. This phase II clinical trial will evaluate an innovative weight-based dosing regimen intended to rapidly and safely normalize vitamin D levels in critically ill children. Study findings will be used to inform the design of a multicenter phase III trial evaluating the clinical and economic benefits to rapid normalization. Recruitment for this trial was initiated in January 2016 and is expected to continue until November 30, 2017.

Clinicaltrials.gov NCT02452762.

Biologically active vitamin D (1,25-dihydroxycholecalciferol or 1,25(OH)2D) is synthetized from inactive prohormone 25-hydroxycholecalciferol (25(OH)D) by the enzyme CYP27B1 1-α-hydroxylase in kidney and several extrarenal tissues including breast. Although the development of breast cancer has been linked to inadequate vitamin D status, the importance of bioactive vitamin D production within tumors themselves is not fully understood. To investigate the role of tumoral vitamin D production in mammary epithelial cell progression to breast cancer, we conducted a Cre-loxP-mediated Cyp27b1 gene ablation in the mammary epithelium of the polyoma middle T antigen-mouse mammary tumor virus (PyMT-MMTV) mouse breast cancer model. Targeted ablation of Cyp27b1 was accompanied by significant acceleration in initiation of spontaneous mammary tumorigenesis. In vivo, cell proliferation, angiogenesis, cell cycle progression, and survival markers were up-regulated in tumors by Cyp27b1 ablation, and apoptosis was decreased. AK thymoma (AKT) phosphorylation and expression of several components of nuclear factor κB (NF-κB), integrin, and signal transducer and activator of transcription 3 (STAT3) signaling pathways were increased in Cyp27b1-ablated tumors compared with nonablated controls. In vitro, 1,25(OH)2D treatment induced a strong antiproliferative action on tumor cells from both ablated and nonablated mice, accompanied by rapid disappearance of NF-κB p65 from the nucleus and segregation in the cytoplasm. In contrast, treatment with the metabolic precursor 25(OH)D was only effective against cells from nonablated mice. 25(OH)D did not inhibit growth of Cyp27b1-ablated cells, and their nuclear NF-κB p65 remained abundant. Our findings demonstrate that in-tumor CYP27B1 1-α-hydroxylase activity plays a crucial role in controlling early oncogene-mediated mammary carcinogenesis events, at least in part by modulating tumoral cell NF-κB p65 nuclear translocation.

Vitamin D intoxication is characterized by elevated serum 25-hydroxyvitamin D (25(OH)D) and suppressed serum 1,25-dihydroxvitamin D (1,25(OH)2D). We evaluated two adolescents with hypercalcemia due to vitamin D intoxication; both had elevated serum 1,25(OH)2D by Diasorin RIA, but normal serum 1,25(OH)2D concentrations by liquid chromatography-tandem mass spectrometry (LC-MS/MS).

This study aimed to determine the effect of 25(OH)D2 and 25(OH)D3 on 1,25(OH)2D concentration determined using RIA and LC-MS/MS.

Pools of normal serum and an artificial serum matrix were prepared and aliquots were spiked with >99% pure 25(OH)D2 or 25(OH)D3 (50-700 ng/mL). Samples were maintained at 4°C or heated to 56°C, and the concentrations of vitamin D metabolites were measured by LC-MS/MS and Diasorin RIA.

Median 1,25(OH)2D increased by 114% with RIA and 21% with LC-MS/MS with addition of 100 ng/mL 25(OH)D3, and 349% (RIA) and 117% (LC-MS/MS) with 700 ng/mL of 25(OH)D3. Each 1-ng/mL increase in 25(OH)D3 increased 1,25(OH)2D by 0.231 pg/mL (RIA) and 0.121 pg/mL (LC-MS/MS). Spiking with 25(OH)D2 led to similar changes. Heat inactivation of serum, and using an artificial serum matrix, were associated with similar effects of 25(OH)D on 1,25(OH)2D assays.

Vitamin D intoxication with high serum levels of 25(OH)D2 or 25(OH)D3 can be associated with elevated levels of 1,25(OH)2D due to interference in a commonly used RIA. A similar but attenuated effect also occurs when 1,25(OH)2D is measured using LC-MS/MS but does not seem to be clinically significant. The basis for this effect on the LC-MS/MS assay is presently uncertain.

Hip pain is a common complaint in a pediatric emergency department. The causes of hip pain are diverse and generally include traumatic and infectious causes. We report a case of hip pain caused by deep soft tissue infection associated with hypercalcemia and primary hyperparathyroidism. Atypical presentation of primary hyperparathyroidism may result in a delay in diagnosis.

Profound hypercalcemia is usually due to underlying malignancy.

We describe a case of granulomatous myositis presenting with extreme hypercalcemia of 20.1 mg/dl and generalized weakness that did not resolve despite rapid correction of serum calcium. The disease process was unmasked by cholecalciferol supplementation. Initial search for a malignant process yielded no diagnosis, but an elevated 1,25-dihydroxyvitamin D level, in the setting of a suppressed PTH and undetectable PTHrP, pointed to the presence of excessive 1α-hydroxylase activity.

Biopsy of the vastus lateralis muscle showed extensive granulomatous myositis. Immunohistochemical staining for 1α-hydroxylase was localized to the multinucleated giant cells and histiocytes. Musculoskeletal magnetic resonance imaging showed involvement of proximal muscle groups of both thighs and upper limbs.

Measurement of vitamin D metabolites is pivotal in diagnosing 1,25-dihydroxyvitamin D-mediated hypercalcemia. Granulomatous disease can occasionally cause profound hypercalcemia and needs to be considered in the differential diagnosis. 1,25-Dihydroxyvitamin D-mediated hypercalcemia is responsive to glucocorticoid therapy.

Hypercalcemia is an uncommon complication of disseminated granulomatous infections. The pathogenesis of hypercalcemia associated with infection is not clear.

We investigated a case of disseminated coccidioidomycosis with hypercalcemia. We used a sensitive radioimmunoassay to measure serum parathyroid hormone-related peptide (PTHrP) and a mouse monoclonal antibody to PTHrP to immunostain biopsies.

We found elevated serum levels of PTHrP while the patient was hypercalcemic that became undetectable when serum calcium normalized. We also found that the inflammatory cells and some surrounding tissues in skin biopsies expressed PTHrP. PTHrP was expressed by all biopsied lesions of patients with coccidioidomycosis that we examined, whether localized to the lung or disseminated, but no other cases were hypercalcemic. PTHrP was also expressed by the 3 mycobacterial granulomas we examined, and in a lymph node from a patient with sarcoidosis.

The expression of PTHrP is a property of infectious granulomas regardless of etiology or the tissue involved, suggesting that PTHrP expression is part of the normal granulomatous immune response. Hypercalcemia may result if there is disseminated infection and multiple granulomas. We propose that excess production of PTHrP is the cause of hypercalcemia in granulomatous infections.

Calcitriol-mediated hypercalcemia resulting from elevated extrarenal 25-hydroxyvitamin D-1alpha-hydroxylase (1alpha-hydroxylase) activity has not previously been described in giant cell polymyositis.

We report an unusual case of hypercalcemia due to disseminated granulomatous disease in a 62-yr-old woman with profound proximal muscle weakness and weight loss. She was initially diagnosed with vitamin D deficiency myopathy with a low serum 25-hydroxyvitamin D; serum calcium at this time was low-normal. Vitamin D(3) 3000 IU daily was prescribed. One month later, blood work showed new hypercalcemia and hypercalciuria with normalized 25-hydroxyvitamin D. 1,25-dihydroxyvitamin D was high-normal, despite a suppressed PTH, undetectable PTHrP, and essentially normal renal function. Her hypercalcemia resolved, and her strength improved only after prednisone was added to bisphosphonate therapy. Two weeks later, she died from acute congestive heart failure.

Autopsy revealed a disseminated giant cell myositis affecting skeletal, cardiac, and gastrointestinal smooth muscle. Immunohistochemistry localized 1alpha-hydroxylase to the inflammatory infiltrates in skeletal and cardiac muscle.

A review of English publications in Medline and Embase, including a reference search of retrieved articles, revealed that calcitriol-mediated hypercalcemia has been described in over 30 conditions, most of which are granulomatous in nature, ranging from inflammatory conditions and foreign body exposures to infections and neoplasms.

Hypercalcemia resulting from autonomous 1alpha-hydroxylase activity may be unmasked by low-dose vitamin D supplementation and should not be excluded from the differential diagnosis of nonparathyroid causes if the serum calcitriol is inappropriately normal, rather than frankly elevated.

Vitamin D has been shown to be involved in the host immune response toward Mycobacterium tuberculosis.

To test whether vitamin D supplementation of patients with tuberculosis (TB) improved clinical outcome and reduced mortality.

We conducted a randomized, double-blind, placebo-controlled trial in TB clinics at a demographic surveillance site in Guinea-Bissau. We included 365 adult patients with TB starting antituberculosis treatment; 281 completed the 12-month follow-up. The intervention was 100,000 IU of cholecalciferol or placebo at inclusion and again 5 and 8 months after the start of treatment.

The primary outcome was reduction in a clinical severity score (TBscore) for all patients with pulmonary TB. The secondary outcome was 12-month mortality. No serious adverse effects were reported; mild hypercalcemia was rare and present in both arms. Reduction in TBscore and sputum smear conversion rates did not differ among patients treated with vitamin D or placebo. Overall mortality was 15% (54 of 365) at 1 year of follow-up and similar in both arms (30 of 187 for vitamin D treated and 24 of 178 for placebo; relative risk, 1.19 [0.58-1.95]). HIV infection was seen in 36% (131 of 359): 21% (76 of 359) HIV-1, 10% (36 of 359) HIV-2, and 5% (19 of 357) HIV-1+2.

Vitamin D does not improve clinical outcome among patients with TB and the trial showed no overall effect on mortality in patients with TB; it is possible that the dose used was insufficient. Clinical trial registered with www.controlled-trials.com/isrctn (ISRCTN35212132).

Disorders of mineral metabolism are common in both the office and hospital setting. The diagnosis can be simplified by remembering the target organs involved--intestine, kidney, and bone--and by assessing the presence of kidney disease, levels of parathyroid hormone, and vitamin D status. Although the list of possible causes for these derangements is long, most patients who have hypercalcemia have hyperparathyroidism or malignancy; those who have hypocalcemia, hypophosphatemia, and hypomagnesemia have reduced gastrointestinal absorption, and those who have hyperphosphatemia and hypermagnesemia have increased intake in the setting of kidney disease.

Hypercalcaemia in patients with HIV infection is usually associated with specific conditions such as lymphoma and granulomatous diseases. We described a case of severe hypercalcaemia consequent to vitamin D intoxication and secondary renal failure in a HIV patient under tenofovir using. Serum creatinine and calcium returned to near normal levels after vitamin D discontinuation, saline and furosemide administration. Some aspects of the drug-induced nephropathy are discussed.

Laboratory reports of elevated serum calcium are common in both inpatient and outpatient settings. Distinguishing between measurements likely to cause symptoms and that require correction from those that are benign poses a challenge to the physician. Calcium stores, serum measurement, and regulation are reviewed as an introduction to understanding the etiology and treatment of hypercalcemia.

The superior soft tissue contrast and multiplanar capability of MR imaging has contributed to earlier diagnosis and implementation of effective treatment for a variety of arthropathies and infectious conditions of the elbow, wrist, and hand. Because of overlapping clinical signs and symptoms, MR imaging plays an important role in delineating the features and staging of each of these conditions. This article discusses the seropositive and seronegative inflammatory arthropathies, with emphasis on early detection and surveillance, as well as gout, synovial osteochondromatosis, pigmented villonodular synovitis, tenosynovitis, and de Quervain's tenosynovitis. Certain noninflammatory arthritides and infectious conditions are also reviewed.

To report a case of extensive calcinosis cutis presumably caused by silicone injections, which was complicated by hypercalcemia.

A long-standing case of calcinosis cutis with subsequent development of hypercalcemia is presented, and possible mechanisms for the underlying metabolic dysfunction are discussed.

A 78-year-old woman presented with severe hypercalcemia and was found to have extensive subcutaneous calcifications on the anterior chest wall and abdomen, likely related to previous silicone injections. The hypercalcemia was treated with intravenously administered pamidronate and aggressive rehydration. Resection of the extensive long-standing calcific deposits was not a viable option. The hypercalcemia resolved with treatment, but the patient died of urinary tract sepsis.

Extensive calcinosis cutis can result in hypercalcemia, possibly attributable to granulomatous reaction and vitamin D excess.

Vertebral fractures due to osteoporosis are a common but frequently unrecognized complication in established ankylosing spondylitis (AS). It is known that inflammatory activity in rheumatic diseases (i.e., proinflammatory cytokines) itself plays a possible role in the pathophysiology of bone loss. The aim of this study was to analyze whether inflammatory activity and an alteration of the vitamin D metabolism play a substantial role in the loss of bone mass in AS. In this cross-sectional study, 58 patients with established AS and an age- and sex-matched control group were examined. The vitamin D status was investigated, as was, in parallel, the relationship to disease activity (erythrocyte sedimentation rate [ESR], C-reactive protein [CRP], Bath Ankylosing Spondylitis Disease Activity Index [BASDAI]), markers of bone metabolism (parathyroid hormone [PTH], 1.25 vitamin D3, 25 vitamin D3), calcium, bone alkaline phosphatase (bone-AP), urine cross-links, and plasma tumor necrosis factor alpha (TNFalpha). Bone mineral density was measured by quantitative computed tomography (QCT) of the lumbar spine. Osteoporosis was diagnosed in early as well as in progressive stages of AS (23/58=39.6%). Furthermore, serum levels of 1.25 vitamin D3 and PTH were negatively correlated with disease activity and TNFalpha. The excretion of cross-links showed a positive correlation with disease activity and TNFalpha, and 1.25 vitamin D3 and PTH were positively correlated with bone-AP. TNFalpha also positively correlated with disease activity. AS patients with osteoporosis showed significantly increased CRP, ESR, cross-links and PTH and a significantly decreased 1.25 D3. Osteoporosis is frequent in AS and high disease activity is associated with an alteration in vitamin D metabolites and increased levels of bone resorption in active AS. Our findings propose a close association of BMD, bone metabolism and inflammatory activity, possibly related to vitamin D inflammation interactions.

A vaccine of native PZP with Freund's adjuvant has been widely used in zoo and wild ungulates, but safety in felids has not been evaluated. General health, immune response, and ovarian histology were assessed in five domestic cats vaccinated with PZP-Freund's and five cats given Freund's adjuvant alone. Peak antibody titers occurred 3 weeks after the third vaccination, and no ovarian lesions were present 6 months after vaccination. Seven cats developed extensive granulomatous reactions at injection sites, lymph nodes, and multiple visceral organs including lungs and brain. Persistent hypercalcemia and compromised renal function occurred in three cats with elevated serum calcitriol of probable macrophage origin. One cat died from an injection site sarcoma. Because of these severe adverse reactions, Freund's adjuvant is contraindicated in cats, and other adjuvants for PZP vaccines should be tested in cats for adverse reactions before use.

The superior soft tissue contrast and multiplanar capability of MR imaging has contributed to earlier diagnosis and implementation of effective treatment for a variety of arthropathies and infectious conditions of the elbow, wrist, and hand. Because of overlapping clinical signs and symptoms, MR imaging plays an important role in delineating the features and staging of each of these conditions. This article discusses the seropositive and seronegative inflammatory arthropathies, with emphasis on early detection and surveillance, as well as gout, synovial osteochondromatosis, pigmented villonodular synovitis, tenosynovitis, and de Quervain's tenosynovitis. Certain noninflammatory arthritides and infectious conditions are also reviewed.

Sarcoidosis is a systemic granulomatous disease that frequently involves the lung. Although classically thought of as a restrictive lung disease, airway obstruction has become a recognized feature of the disease in the past years. Sarcoidosis can affect the airway at any level and when the involvement includes small airways, it can resemble more common obstructive airway diseases, such as asthma and chronic bronchitis. Pulmonary function testing and high-resolution computerized tomography of the chest are two important tools to evaluate the presence and extent of airway obstruction in sarcoidosis. Pharmacologic options for the treatment of obstructive sarcoidosis are, in large part, not supported by large, randomized clinical trials. In severe cases of bronchostenosis owing to sarcoidosis granuloma or extrinsic compression from intrathoracic lymphadenopathy, interventional bronchoscopy has successfully been performed, although repeated procedures are usually required. Lung transplantation is an ultimate option in selected patients with late-stage fibrotic disease.

Magnetic resonance (MR) imaging reveals a broad range of musculoskeletal abnormalities in patients with sarcoidosis, including focal and diffuse muscle lesions, soft-tissue masses, joint abnormalities, and marrow infiltration of small and large bones. Long bone and axial skeletal involvement may be occult at conventional radiography but depicted at MR imaging, with an appearance that resembles that of osseous metastases. Sarcoidosis-related findings may be detected at dedicated MR imaging for osteoarticular symptoms in sarcoidosis patients or encountered incidentally at MR imaging performed for other indications. Correlation with clinical and laboratory findings is essential for correct diagnosis because the MR imaging findings are nonspecific in most cases. The radiologist should be aware of potential sarcoidal causes in the differential diagnosis of musculoskeletal lesions in patients with proved or suspected sarcoidosis. Such consideration will have a profound effect on the interpretation of images and on the study of patients with dual diagnoses of sarcoidosis and neoplasm.

Supplementation with vitamin D3 was previously shown to protect Escherichia coli challenged birds that underwent two dexamethasone (DEX) treatments at 5 and 12 wk of age in an experimental model of turkey osteomyelitis complex (TOC). The purpose of the present study was to determine the effects of dietary supplementation with 10 microg of 1,25 dihydroxyvitamin D3 (1,25D)/ kg feed or 99 microg of 25-hydroxyvitamin D3 (25D)/kg feed on disease resistance in the same model. Birds were fed the supplemented diets continuously and ad libitum. Seven hundred twenty turkey poults were placed into 24 floor pens in a 3 x 2 x 2 design (three vitamin D treatments, two DEX treatments, two E. coli treatments, with two replicate pens per treatment). At 5 wk of age, half of the birds were treated with DEX, and half of the DEX-treated birds and half of the nontreated birds were challenged with E. coli. All mortalities and lame birds were necropsied. At 9 wk, all of the DEX- or E. coli-treated birds were given another series of DEX injections; 2 wk later 10 birds per pen were necropsied. At 12 wk, survivors of the previous challenges were given a third DEX treatment, and all birds were necropsied 2 wk later. After the first series of DEX injections, mortality was increased in the 25D-supplemented birds that were given the DEX treatment and the E. coli challenge. After the second series of DEX injections, the main effect mean BW was significantly lower in birds given 1,25D as compared to controls and 25D-supplemented birds. Mortality was higher in 1,25D-supplemented birds that were challenged with E. coli at 5 wk and treated with DEX at 9 wk as compared to 25D-supplemented birds. The 1,25D-treated birds that were treated with DEX at 5 and 9 wk and challenged with E. coli at 5 wk had higher mortality and air sacculitis scores as compared to controls and 25D-treated birds. The main effect mean mortality was significantly higher in birds given 1,25D as compared to controls and 25D-treated birds. The percentage of birds with TOC lesions was decreased from 27% to 0 by 25D and 1,25D in the groups given two DEX treatments and E. coli challenge. After the third DEX treatment, BW of 1,25D-suppplemented birds was decreased, and mortality and air sacculitis scores were increased. Bone strength was generally increased by supplementation with 1,25D, whereas 25D supplementation increased bone strength only in birds challenged at 5 wk and treated with DEX at Weeks 9 and 12. In this study, supplementation with vitamin D metabolites decreased TOC incidence in E. coli-challenged birds given two DEX treatments. However, toxic effects were observed in most supplemented DEX-treated birds and may be attributed to an additive effect of DEX treatment, E. coli septicemia, and vitamin D supplementation.

Hypercalcaemia has been known to occur in association with granulomatous diseases. The aim of this study was to ascertain the incidence of hypercalcaemia and determine the prevalence of symptoms associated with it in Greek patients with newly-diagnosed tuberculosis (TB), before the initiation of anti-tuberculosis treatment. We prospectively evaluated all patients with newly-diagnosed TB presenting, either as inpatients or as outpatients, to our hospital, during a 3-year period. We evaluated 88 patients with TB (50 males and 38 females), aged between 23 and 89 years (mean age+/-SD: 46.4+/-19 years), and 65 age- and sex-matched controls with chronic obstructive pulmonary disease (36 males and 29 females), aged between 28 and 88 years (mean age+/-SD: 47.2+/-18 years). Among TB patients, 56 had pulmonary TB, 20 had pleural TB without evidence of pulmonary parenchyma involvement, eight had pulmonary and pleural TB, and four had disseminated disease. The mean (+/-SD) albumin-adjusted serum calcium concentration and the mean ionized calcium concentration were significantly higher in the TB group (2.49+/-0.21 mmol l(-1) and 1.27+/-0.02 mmol l(-1) respectively) than in the control group (2.36+/-0.11 mmol l(-1) and 1.19+/-0.02 mmol l(-1), P<0.05). In the TB group no correlation between type of disease and albumin-adjusted or ionized calcium concentration was seen. Hypercalcaemia was detected in 22 patients with TB (25%) but only three showed symptoms associated with it. We conclude that, although hypercalcaemia is a common laboratory finding among Greek patients with TB before anti-TB chemotherapy, it is usually asymtomatic.

Hypercalcaemia may complicate granulomatous diseases, such as tuberculosis and sarcoidosis, and various AIDS-related opportunistic infections and malignancies. We report here two patients with AIDS and disseminated Mycobacterium avium infection who developed symptomatic hypercalcaemia several weeks after commencing antimycobacterial chemotherapy, and in whom inappropriately elevated 1,25(OH)(2)D(3)levels were documented. Although vitamin D supplementation may have contributed, no other cause for the hypercalcaemia was found. The biochemical and clinical similarities between these cases and other hypercalcaemic granulomatous diseases suggest a common mechanism related to macrophage activation and dysregulated vitamin D production.

To investigate the effects of lead and cadmium on the metabolic pathway of vitamin D3.

Blood and urinary cadmium and urinary total proteins were measured in 59 smelter workers occupationally exposed to lead and cadmium. In 19 of these workers, the plasma vitamin D3 metabolites, (25-hydroxycholecalciferol (25 OHD3), 24R, 25-dihydroxycholecalciferol (24R,25(OH)2D3) and 1 alpha,25-dihydroxycholecalciferol (1 alpha, 25(OH)2D3)) were measured together with blood lead. Vitamin D3 metabolites were measured by radioimmunoassay, (RIA), lead and cadmium by atomic absorption spectrophotometry, and total proteins with a test kit.

Ranges for plasma 25(OH)D3, 24R,25(OH)2D3 and 1 alpha,25(OH)2D3 were 1.0-51.9 ng/ml, 0.6-5.8 ng/ml, and 0.1-75.7 pg/ml, respectively. Ranges for blood lead were 1-3.7 mumol/l, (21-76 micrograms/dl), blood cadmium 6-145 nmol/l, and urinary cadmium 3-161 nmol/l. Total proteins in random urine samples were 2.1-32.6 mg/dl. Concentrations of lead and cadmium in blood showed no correlation (correlation coefficient -0.265) but there was a highly significant correlation between blood and urinary cadmium. Concentrations for 24R,25(OH)2D3 were depressed below the normal range as blood and urinary cadmium increased, irrespective of lead concentrations. High cadmium concentrations were associated with decreased plasma 1 alpha,25(OH)2D3 when lead concentrations were < 1.9 mumol/l and with above normal plasma 1 alpha,25(OH)2D3 when lead concentrations were > 1.9 mumol/l, Kruskal-Wallis analysis of variance (K-W ANOVA) chi 2 = 10.3, p = 0.006. Plasma 25(OH)D3 was negatively correlated with both urinary total proteins and urinary cadmium, but showed no correlation with plasma 24R,25(OH)2D3, 1 alpha,25(OH)2D3, blood lead, or blood cadmium.

Continuous long term exposure to cadmium may result in a state of equilibrium between blood and urinary cadmium. Cadmium concentrations in blood could be predicted from the cadmium concentration of the urine, (regression coefficient +0.35 SE 0.077). Exposure to cadmium alone decreased the concentrations of 1 alpha,25(OH)2D3 and 24R,25(OH)2D3, whereas exposure to both cadmium and lead increased the concentrations of 1 alpha,25(OH)2D3. It has been suggested that cadmium and lead interact with renal mitochondrial hydroxylases of the vitamin D3 endocrine complex. Perturbation of the vitamin D metabolic pathway by cadmium may result in health effect, such as osteoporosis or osteomalacia, risks which are possibly increased in the presence of lead.