Adnan AYVAZ, Murat SANCAKTAR, Fatoş TANZER, Mehtap FIRAT

Three case reports of alkaptonuria, a rare metabolic disease, in two first-degree relatives and one patient

Alkaptonuri, tirozini katalizleyen homogentisat 1, 2-dioxygenase (HGO) enziminin eksikliğine bağlı, bağ dokusunda koyu pigmentasyon artışı ve idrarın siyahımsı anormal renk değişimi ile karakterize kalıtımsal nadir bir hastalıktır. Bu çalışmada, tanıları idrar homogantisik asit miktarı ile doğrulanan, alkaptonurili beş yaşında bir erkek çocuk ve iki yaşındaki kız kardeşi ile akrabaları olmayan 11 aylık bir erkek çocuk hasta sunuldu. Bu üç olgunun idrar örneklerindeki homogentisik asit (HGA) seviyelerinde sırasıyla 14, 14 ve 24 kat artış gösterildi. Hastalığın tedavisi HGA üretiminin düzeltilmesi ve komplikasyonlarından korunma üzerine yoğunlaşmıştır. HGA atılımının azaltılması için C vitamini tedavisi ve diyette protein alımının kısıtlanması önerilmektedir. Hastalarımızın diyetlerindeki düşük protein tüketimi nedeniyle büyüme-gelişmeleri normaldi ve hastalığın ana komplikasyonları bulunmuyordu.

İki akraba ve bir hastada nadir bir metabolik hastalık olan alkaptonürili üç olgu sunumu

Alkaptonuria is a rare hereditary disease, characterized by an abnormal blackish coloration of the urine, dark pigmentation of the connective tissue which is due to a deficiency in homogentisate 1, 2-dioxygenase (HGO), a tyrosine catabolizing enzyme. In this study two-years-old girl, five-year-old boy siblings and 11-month-old boy with alkaptonuria were presented. The diagnosis was confirmed by urinary homogentisic acid (HGA) amount. Normal levels of HGA in urine are 2.4 – 12 ng/ml. In these three cases within urine samples, the level of HGA (2.5-dihydroxyphenylacetic acid) showed an increase of 14, 14, 24 fold, respectively. The treatment focuses upon these aspects: correction of the production of HGA and prevention of complications. For reduction of HGA excretion has been suggested treatment with vitamin C and protein restriction have been proposed. Our patients were showed normal growth and development and no major complications of the disease because of consuming a diet with low protein.

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