Severe acute kidney injury due to oxalate crystal induced severe interstitial nephritis: A case report

Table 1 Laboratory test results

Diagnostic test	Normal value	At presentation	Hospital day 2	Hospital day 6	On discharge	Follow-up
Hemoglobin, g/dL	11.6-15.0	9.0	7.6	9.1	7.3
White blood cell count, × 109 /L	3.4-9.6	6.0	4.3	16.8	9.2
Platelet count, × 109/L	157-371	243	207	168	124
Serum urea nitrogen, mg/dL	6-21	69	62	55	34	23
Serum creatinine, mg/dL	0.59-1.04	10.15	9.10	8.03	5.03	1.6
Serum sodium	135-145 mmol/L	136	143	143	144	137
Serum potassium	3.6-5.2 mmol/L	2.7	3.6	3.9	3.4	3.9
Serum chloride	98-107 mmol/L	95	106	108	109	98
Serum calcium	8.8-10.2 mg/dL	9.4	8.8	8.6	8.4	9.7
Serum phosphorus	2.5-4.5 mg/dL	5.5	5.5	5.2	3.8
Serum magnesium	1.7-2.3 mg/dL	2.3	2.0	1.6
Serum bicarbonate	22-29 mmol/L	24	21	21	22	26
eGFR	≥ 60 mL/min/BSA	< 15	< 15	< 15	< 15	34
Anion gap	7-15	17	16	14	13	13
Serum albumin	3.5-5.0 g/dL	3.7

eGFR: Estimated glomerular filtration rate.

Table 2 Summary of key diagnostic tests

Diagnostic test	Normal value	Result
HCV Ab screen, S	Negative	Negative
HBs antibody, S	Negative	Negative
HBs antigen, S	Non-reactive	Non-reactive
HBc total ab w/reflex, S	Negative	Negative
Complement, C3	75-175 mg/dL	143 mg/dL
Complement, C4	14-40 mg/dL	27 mg/dL
Cryoglobulins	Negative	Negative
GBM, IgG Ab	< 0.1 (Negative) U	< 0.2 U
MPO, Ab	< 0.4 (Negative) U	< 0.2 U
PR 3, Ab	< 0.4 (Negative) U	< 0.2 U
SPEP	No monoclonal protein	-
Haptoglobin, S	30-200 mg/dL	297
Kappa free light Chain, S	0.3300-1.94 mg/dL	13.7
Lambda free light chain, S	0.5700-2.63 mg/dL	8.08
Kappa/Lambda FLC ratio	0.2600-1.65	1.70
DNA double stranded Ab, IgG, S	≤ 4 (Negative) IU/mL	2
Sm. Ab, IgG, S	< 1.0 (Negative) U	< 0.2
CRP	≤ 8.0 mg/L	< 3.0 mg/L
Bilirubin, total	≤ 1.2 mg/L	0.8
ALT, S	7-45 U/L	11
AST, S	8-43 U/L	17
Alkaline phosphatase	35-104 U/L	60
Protein, total	6.3-7.9 g/dL	6.9 g/dL
Albumin	3.5-5.0 g/dL	3.7 g/dL

CRP: C-reactive protein; ALT: Alanine transaminase; AST: Aspartate aminotransferase; HCV: Hepatitis C virus; MPO: Myeloperoxidase; SPEP: Serum protein electrophoresis; GBM: Glomerular basement membrane.