OBJETIVES: Hyperprolinemia type I (HPI) is an inborn error of metabolism caused by proline gene alteration proline dehydrogenase (PRODH) on chromosome 22q11, which causes increased levels of proline in plasma and urine by decreasing the activity of the proline oxidase (POX). Clinical manifestations can find cognitive and psychiatric disorders, epilepsy and kidney impairment. We present two cases with different clinical expression HPI.

CLINICAL OBSERVATIONS: The first case is a girl who presented development delay and hypotonia at birth and whose Exploration showed macrocephaly, prominent forehead, flattened nasal nose and hypertelorism. Family and personal history normal. With three years starts episodes of cessation of motor activity without automation or abnormal movements of seconds long. EEGs are displayed in several abnormalities multifocal. Shows increase in metabolic study of plasma proline and proline and hydroxyproline increased urine HPI diagnostic support.

The second case is a child with normal physical examination, personal history and family without interest starts at 2 years and 4 months simple partial seizures refractory to antiepileptic treatment. Several electroencephalograms show a right frontotemporal focus. On several occasions the patient had episodes of ataxia associated with fever and intake of certain drugs (phenytoin and oxcarbazepine). In which an increased metabolic study of plasma and urine proline, hydroxyproline and glycine increased in urine and increased glutamine cerebrospinal fluid compatible with all HPI.

COMMENTS: HPI can present with various clinical manifestations, among which predominate seizure. This entity should be included in the differential diagnosis of a child with epilepsy, especially if refractory.