• Biofilm
• Cryptococcus liquefaciens
• Fungal infections
• Hands
• Neonates
• Virulence factors

Cryptococcosis is an infectious disease of worldwide distribution, caused by encapsulated yeasts belonging to the phylum Basidiomycota. The genus Cryptococcus includes several species distributed around the world. The C. gattii/neoformans species complex is largely responsible for most cases of cryptococcosis. However, clinical series have been published of infections caused by Papiliotrema (Cryptococcus) laurentii and Naganishia albida (Cryptococcus albidus), among other related genera. Here, we examined the pathogenic potential and antifungal susceptibility of C. gattii/neoformans species complex (clades I and II) and related genera (Papiliotrema and Naganishia) isolated from environmental and clinical samples. P. laurentii (clade III), N. liquefasciens/N. albidosimilis (clade IV); and N. adeliensis/N. albida (clade V) strains produced higher levels of phospholipase and hemolysins, whereas the C. gattii/neoformans species complex strains (clades I and II) had markedly thicker capsules, produced more biofilm biomass and melanin, which are known virulence attributes. Interestingly, 40% of C. neoformans strains (clade II) had MICs above the ECV established for this species to amphotericin B. Several non-C. gattii/neoformans species complex (clades III to V) had MICs equal to or above the ECVs established for C. deuterogattii and C. neoformans for all the three antifungal drugs tested. Finally, all the non-C. gattii/neoformans clinical isolates (clades III to V) produced more melanin than the environmental isolates might reflect their particularly enhanced need for melanin during in vivo protection. It is very clear that C. gattii/neoformans species complex (clades I and II) strains, in general, show more similar virulence phenotypes between each other when compared to non-C. gattii/neoformans species complex (clades III to V) isolates. These observations together with the fact that P. laurentii and Naganishia spp. (clades III to V) strains were collected from the outside of a University Hospital, identify features of these yeasts important for environmental and patient colonization and furthermore, define mechanisms for infections with these uncommon pathogens.

• Cryptococcus spp.
• Naganishia spp.
• Papiliotrema laurentii
• antifungal drug susceptibility
• virulence factors

• Cryptococcus sp.
• cryptococcosis
• rare yeast

Cryptococcus spp is a major cause of opportunistic infections in immunocompromised patients, primarily due to Cryptococcus neoformans and Cryptococcus gattii. There are occasional reports of other Cryptococcus species causing invasive human disease. However, their epidemiology and clinical significance are not fully defined. We sought to describe cases with cultures positive for Cryptococcus species other than C neoformans and C gattii.

A retrospective descriptive analysis of clinical and laboratory data of patients with cultures growing Cryptococcus species other than C neoformans and C gattii from November 2011 to February 2019 was performed. Three Mayo Clinic sites in Arizona, Florida, and Minnesota were included.

From 176 cases with a culture growing Cryptococcus spp, 54 patients (30%) had a culture for Cryptococcus other than C neoformans and C gattii in the study time frame. The most common species were Cryptococcus magnus, Cryptococcus laurentii, and Cryptococcus ater. The organisms were isolated and identified in culture of bronchoalveolar lavage (11), skin (11), urine (7), oral (4), sinus (3), intraoperative soft tissue (3), sputum (2), synovial fluid (2), cerebrospinal fluid (2), and intravenous catheter (2), among others (7).

Only 8 (15%) cases were considered to be potentially pathogenic, with 1 case of invasive disease. Antifungal treatment was fluconazole, itraconazole, and griseofulvin, for a mean systemic antifungal duration of 42 days.

This large series of patients with Cryptococcus spp other than C neoformans and C gattii suggests that these species rarely cause clinically significant infection in humans. Only 1 case of invasive disease was found.

• Cryptococcus
• fungal infection
• immunocompromised host
• mycology
• non-neoformans/gattii

Despite being associated with a high mortality and economic burden, data regarding candidemia are scant in Algeria. The aim of this study was to unveil the epidemiology of candidemia in Algeria, evaluate the antifungal susceptibility pattern of causative agents and understand the molecular mechanisms of antifungal resistance where applicable. Furthermore, by performing environmental screening and microsatellite typing we sought to identify the source of infection.

We performed a retrospective epidemiological-based surveillance study and collected available blood yeast isolates recovered from the seven hospitals in Algiers. To identify the source of infection, we performed environmental screening from the hands of healthcare workers (HCWs) and high touch areas. Species identification was performed by API Auxa-Color and MALDI-TOF MS and ITS sequencing was performed for species not reliably identified by MALDI-TOF MS. Antifungal susceptibility testing followed CLSI M27-A3/S4 and included all blood and environmental yeast isolates. ERG11 sequencing was performed for azole-resistant Candida isolates. Microsatellite typing was performed for blood and environmental Candida species, where applicable.

Candida tropicalis (19/66) was the main cause of candidemia in these seven hospitals, followed by Candida parapsilosis (18/66), Candida albicans (18/66), and Candida glabrata (7/66). The overall mortality rate was 68.6% (35/51) and was 81.2% for C. tropicalis-infected patients (13/16). Fluconazole was the main antifungal drug used (12/51); 41% of the patients (21/51) did not receive any systemic treatment. Candida parapsilosis was isolated mainly from the hands of HCWs (7/28), and various yeasts were collected from high-touch areas (11/47), including Naganishia albida, C. parapsilosis and C. glabrata. Typing data revealed interhospital transmission on two occasions for C. parapsilosis and C. glabrata, and the same clone of C. parapsilosis infected two patients within the same hospital. Resistance was only noted for C. tropicalis against azoles (6/19) and fluconazole-resistant C. tropicalis isolates (≥8 μg/ml) (6/19) contained a novel P56S (5/6) amino acid substitution and a previously reported one (V234F; 1/6) in Erg11p.

Collectively, our data suggest an urgent need for antifungal stewardship and infection control strategies to improve the clinical outcome of Algerian patients with candidemia. The high prevalence of C. tropicalis joined by fluconazole-resistance may hamper the therapeutic efficacy of fluconazole, the frontline antifungal drug used in Algeria.

• Algeria
• Antifungal susceptibility testing
• Candidemia
• ERG11 sequencing
• Environmental screening
• MALDI-TOF MS
• Microsatellite typing

• Cryptococcal meningitis
• Host DNA contamination
• Metagenomic next-generation sequencing
• Saponin
• Tuberculous meningitis

• Adult
• Aged
• Cerebrospinal Fluid/microbiology
• Cryptococcus/genetics
• Cryptococcus/pathogenicity
• Female
• Genome, Bacterial
• Genome, Human
• High-Throughput Nucleotide Sequencing/methods
• High-Throughput Nucleotide Sequencing/standards
• Humans
• Male
• Meningitis, Cryptococcal/cerebrospinal fluid
• Meningitis, Cryptococcal/diagnosis
• Meningitis, Cryptococcal/microbiology
• Metagenomics/methods
• Metagenomics/standards
• Middle Aged
• Molecular Diagnostic Techniques/methods
• Molecular Diagnostic Techniques/standards
• Mycobacterium tuberculosis/genetics
• Mycobacterium tuberculosis/pathogenicity
• Sensitivity and Specificity
• Sequence Analysis, DNA/methods
• Sequence Analysis, DNA/standards
• Tuberculosis, Meningeal/cerebrospinal fluid
• Tuberculosis, Meningeal/diagnosis
• Tuberculosis, Meningeal/microbiology

Klebsiella pneumoniae (K. pneumoniae) used to affect mainly people with compromised immunity or weakened by other infections, but recent emergence of hypervirulent strains has increased infections even in healthy individuals. These infections include liver abscess, pneumonia, bacteremia, meningitis, necrotizing fasciitis, and endophthalmitis. Although metastatic infection by hypervirulent K. pneumoniae (hvKP) is increasingly recognized, co-infection with Cryptococcus neoformans (C. neoformans) meningitis in immunocompetent hosts is rare but fatal. So, it is necessary to determine the risk factors, complications, and comorbidity of this disease.

This report describes a 58-year-old man with hvKP pulmonary abscess, bacteremia, and meningitis, accompanied by fatal Cryptococcus meningitis. This patient presented with fever for 1 wk and drowsiness for 3 d. Laboratory findings revealed pulmonary abscess and bacteremia of K. pneumoniae. He was given intravenous antibiotic therapy, and the infection was under control for about 1 wk. However, his condition deteriorated rapidly because of metastatic purulent meningitis. Although hvKP and C. neoformans were isolated and confirmed, the patient died of spontaneous respiratory and cardiac arrest caused by cerebral hernia.

HvKP has emerged as a cause of metastatic infections in immunocompetent hosts. polymicrobial co-infections should be taken into consideration when metastatic infection is present.

• Hypervirulent Klebsiella pneumoniae
• Metastatic infection
• Cryptococcus neoformans meningitis
• Comorbidity
• Case report

• Animals
• Antifungal Agents/therapeutic use
• Clinical Laboratory Techniques
• Cryptococcosis/diagnosis
• Cryptococcosis/drug therapy
• Cryptococcosis/pathology
• Cryptococcosis/prevention & control
• Cryptococcus/isolation & purification
• Cryptococcus/pathogenicity
• Cryptococcus/physiology
• Humans
• Lung/microbiology
• Lung/pathology
• Lung Diseases, Fungal/diagnosis
• Lung Diseases, Fungal/drug therapy
• Lung Diseases, Fungal/pathology
• Lung Diseases, Fungal/prevention & control
• Prognosis
• Risk Factors

We report 5 HIV-infected Ugandan adults with cryptococcal and tuberculous (TB) meningitis co-infection. All unmasked meningitis occurred within 5 weeks of starting HIV therapy. Xpert MTB/RIF Ultra facilitated prompt diagnosis; however, 60% in-hospital mortality occurred. TB meningitis coinfection prevalence was 0.8% (5/586) among cryptococcal meningitis, 2 during second cryptococcal episodes.

• HIV/AIDS
• case series
• cryptococcal meningitis
• tuberculosis
• tuberculous meningitis

Cryptococcosis is a life-threatening fungal infection caused by the encapsulated yeasts Cryptococcus neoformans and C. gattii, acquired from the environment. In Latin America, as occurring worldwide, C. neoformans causes more than 90% of the cases of cryptococcosis, affecting predominantly patients with HIV, while C. gattii generally affects otherwise healthy individuals. In this region, cryptococcal meningitis is the most common presentation, with amphotericin B and fluconazole being the antifungal drugs of choice. Avian droppings are the predominant environmental reservoir of C. neoformans, while C. gattii is associated with several arboreal species. Importantly, C. gattii has a high prevalence in Latin America and has been proposed to be the likely origin of some C. gattii populations in North America. Thus, in the recent years, significant progress has been made with the study of the basic biology and laboratory identification of cryptococcal strains, in understanding their ecology, population genetics, host-pathogen interactions, and the clinical epidemiology of this important mycosis in Latin America.

• Aspergillus
• Candida
• Cryptococcus
• Penicillium
• Scedosporium
• antifungal resistance
• environmental fungi
• fungal virulence
• global warming
• thermotolerance

Invasive fungal infections, including cryptococcosis, are a growing threat to immunocompromised patients. Although Cryptococcus neoformans and Cryptococcus gattii are the main agents of human cryptococcosis, opportunistic infections by environmental species, such as C. liquefaciens, have been observed recently. The main Cryptococcus virulence factor is the production and secretion of polysaccharides (PS). Previously, we showed that both species produce PS of similar composition. Here, we examined the ultrastructure and biological activity of capsular and secreted PS from C. liquefaciens, and yeast pathogenicity to an invertebrate host, in comparison with C. neoformans. Ultrastructural analysis by high-resolution microscopy showed that both species produce large and complex capsules. PS from both species had indistinguishable effects on phagocytosis levels, NO production and the secretion of a variety of immune mediators. Challenge with C. liquefaciens or C. neoformans led to complete lethality of G. mellonella larvae. Treatment with C. liquefaciens PS could not protect mice against infection with C. neoformans. We conclude that polysaccharides of the environmental yeast C. liquefaciens have strikingly similar ultrastructural and biological properties to those of C. neoformans, highlighting the importance of monitoring the emergence of new fungal pathogens for which thermotolerance may be an important transitional step towards pathogenesis in humans.