histidinuria renal tubular defect syndrome histidinuria renal tubular defect syndrome histidinuria-renal tubular defect syndrome is a rare genetic disorder characterized by histidinuria associated with the intestines' and the renal tubule's impaired ability of absorbing histidine. additional findings include intellectual disability, developmental delay, epilepsy, and mild congenital variations. only five cases (all male) from four families have been described in medical literature. histidinuria-renal tubular defect syndromeother namesrenal histidinuria, histidinuria due to a renal tubular defectspecialtymedical geneticscausesmedical genetics