an unusual presentation of a child with hyperoxaluria

Introduction:hyperoxaluria is a common abnormal finding in patients with nephrolithiasis, especially in children in contrary to adults. overall, it is a rare disorder with the four main types of primary, enteric, dietary and idiopathic. the disorder is characterized by overproduction of oxalate that leads to nephrocalcinosis and eventual development of endstage renal failure. case presentation:we report the case of a 2yearold boy presented with multiple episodes of seizure, gastrointestinal bleeding, loss of consciousness and rise in blood urea nitrogen (bun) and creatinine (cr). he underwent imaging study and lumbar puncture with the suspicion of encephalitis. with more historytaking, we understood that he was previously under treatment for nephrocalcinosis. finally, he underwent dialysis and the level of consciousness improved. his diagnosis was confirmed by renal biopsy and establishing the existence of extensive tubular and interstitial crystal deposition in his kidneys. conclusions:the case illustrates the need for the early diagnosis of this disorder to prevent systemic oxalosis that affects many organs resulting in severe morbidity and mortality and raising the suspicion of primary hyperoxaluria in childhood progressive renal failure with massive nephrocalcinosis, especially if accompanied by a positive family history. in these cases, complications should be explained to increase drug compliance.