Case report: A 17 months old girl was referred to the neurologist because of walking difficulties which were in fact due to abdominal distension. Hepatosplenomegaly was documented clinically and by abdominal ultrasound and CT. Diagnostic work-up revealed renal Fanconi syndrome, the clue symptom leading to the correct diagnosis by determination of urinary succinylacetone. Severe liver cirrhosis with oedemas and ascites, and acute respiratory distress syndrome necessitated resuscitation in the ICU until a favorable response to treatment by NTBC. After two months, regression of hepatomegaly and of the enlarged size of the spleen was observed, even if splenomegaly in this case was indicative of severe liver cirrhosis with consecutive portal hypertension. Conclusion: Splenomegaly as a marker of hepatic cirrhosis may be a revealing symptom of tyrosinemia type 1. Background: Treatment of Tyrosinemia type I consists of NTBC and dietary restriction of Phenylalanine (Phe) and Tyrosine (Tyr). Case Report: Our patient was born after an uneventful pregnancy/delivery. At day 7 she was admitted because of positive NBS results for TYR1 (succinylacetone 4.7 μmol/l; threshold 1.2 μmol/l). Treatment was initiated with NTBC and restriction of Phe and Tyr (breastfeeding combined with Phe and Tyr free formula), based on blood Tyr concentrations. Due to increased Tyr concentrations, natural protein intake was decreased to a minimum of 0.5 g/kg/day. During the subsequent months, she developed first eczema, while later decreased growth parameters followed, and thereafter cortical myoclonus appeared and decreased psychomotor development seemed to arise despite adjustments of the natural protein intake both ways, and Tyr concentrations varying from some 215 to 609 μmol/l . Because of hypophenylalaninemia (< 20 μmol/l),~30 mg/kg/ day Phe-supplementation was started at day 192. Subsequently, all parameters improved. Conclusion: The need of Tyr and Phe varies among patients. Extra Phe usually is not considered as Phe is largely converted into tyrosine. However, this case shows that hypophenylalaninemia is an important complication, necessitating Phe-supplementation, even when this results in lower natural protein intake. Homogentisic acid (HGA) is a diagnostic metabolite that accumulates in patients with alkaptonuria. The cause of the disease is deficiency of homogentisic acid oxidase. Patients with alkaptonuria excrete HGA in the urine. Therefore diagnosis of alkaptonuria can be confirmed by urine HGA analysis. Capillary electrophoresis (CE),a highly effective analytical technique, has been employed for the clinical analysis. The advantage of CE method is high separation efficiency, excellent resolution, short analysis time, electrolyte and sample consumption. CE is particularly suitable in the analysis of complex natural matrices, owing to its higher resolving power. Therefore, biological fluids can be directly analyzed without any pretreatment step or with a simple process of sample pretreatment by CE. In this work CE method for the determination of HGA in urine samples has been developed and validated. Separation and determination were carried out with ultraviolet detector at 190 nm. The optimum conditions were achieved using phosphate buffer 47 mM at pH 7.0 and voltage of 22 kV. Under these conditions the presence of HGA is detected in less than 8 min. Good linearity (r2>0.99) and repeatability (%RSD<2%) was obtained. The developed method was simple, easy, rapid and inexpensive for quantitative determination of urinary HGA. Background: Large amounts of glycine (Gly) occur in brain of patients affected by nonketotic hyperglycinemia (NKH), which is an inherited disorder characterized by brain abnormalities whose pathomechanisms are still poorly established.