A 2-month-old healthy thriving term male infant presented with hypocalcaemic generalised tonic–clonic seizures associated with renal failure (plasma creatinine level 198 μmol/l), severe metabolic acidosis (pH 6.94) and pancytopenia. Renal ultrasound showed bilateral echogenic kidneys, unlike classical nephrocalcinosis with mild prominence of the pelvicalyceal systems (fig 1). Figure 1 Renal ultrasound showed bilateral globally echogenic kidneys with some loss of corticomedullary differentiation and mild prominence of pelvicalyceal systems (the left and right kidneys measured 5.6 and 5.7 cm, respectively, with the 50th centile for age …