A 78-year-old man who had stable chronic kidney disease (CKD) presented with marked elevation of his serum creatinine of 6.0 mg/dl compared to his baseline 2.05 mg/dl.His presenting history, vitals and physical examination did not allude to a prerenal cause for acute kidney injury (AKI).His urinalysis was unremarkable with no evidence of white cell or red cell casts, there was no evidence of obstructive uropathy, negative serologies for autoimmune and viral etiologies and negative for anti-neutrophil cytoplasmic antibody (ANCA) and anti-glomerular basement membrane (anti-GBM).Although his urinalysis was unremarkable, urine eosinophil was positive.He underwent a kidney biopsy which showed acute tubular injury associated with extensive calcium oxalate crystal deposition.On revisiting his history, it was discovered the patient was consuming 3-4 oz of cashew nuts daily for the last one year.This is an uncommon case and highlights the need for heightened awareness of the dietary implications in patients with CKD and the need for adequate counseling and intervention.
Ramrattan et al. (Wed,) studied this question.