Interdisciplinary treatment of early-onset ornithine transcarbamylase (OTC) deficiency.: Two case reports and a review

Patient reports: We report on a male preterm infant (gestational age 31 weeks, birth weight 1420 g) and a male term infant (gestational age 38 weeks, birth weight 3680 g) with ornithine transcarbamylase (OTC) deficiency. After inconspicuous cardiopulmonary adjustment, both entered a state of metabolic crisis with respiratory insufficiency and ventilatory requirement at the 2nd and 4th day of life, respectively. Diagnosis of hyperammonemia (NH3 > 1000 mu mol/l) was followed by the detection of a plasma amino acid pattern that is typical for OTC-deficiency and an excessive orotic aciduria. Beside intravenous treatment (insulin-glucose-infusion, lipid infusion, sodium benzoate, arginine, L-carnitine), the preterm infant received an exchange transfusion and was supplied with central venous catheters, hemofiltration and hemodialysis. He died after severe disturbances of circulation and coagulation at the 14th day. The male term infant tolerated the effective hemofiltration and was dicharged home with specific therapy at day 26. Conclusions: Time of diagnosis and influence of additional risk factors are decisively for the prognosis of OTC-deficiency. The immediate aims of therapy (stabilization of vital functions, reduction of plasma ammonium, control of nutrition) can only be realized in cooperation between neonatology, division of metabolism, pediatric nephrology and pediatric surgery.