[Lysinuric protein intolerance].

We report the first case of lysinuric protein intolerance observed in Germany. A girl of Turkish ancestry suffered from severe dehydration at the age of 6 months after changing from breast milk to cow milk. Because of a microcytic hypochromic anaemia and erythrophagocytosis in the bone marrow a hematologic disease (Farquar's disease) was suspected. The definite diagnosis of lysinuric protein intolerance was eventually clarified by the following laboratory and clinical data: increased urinary excretion and low plasma concentration of lysine, arginine and ornithine, apathy, vomiting, diarrhea and hyperammonemia after an oral protein load, high serum LDH-activity, ferritinemia, and increased urinary excretion of orotic acid. Under therapy with citrullin and a low-protein diet the metabolic situation remained stable, even during infections. The bone marrow findings have been reported only in one further case of lysinuric protein intolerance.