Beta-ketothiolase Deficiency: Two Case Reports

Abstract

Abstract

Beta-ketothiolase deficiency is an autosomal recessive disorder, a rare disorder of isoleucine and ketone metabolism. This disorder is clinically characterized by ketoacidotic attacks. Ketoacidosis, vomiting, and dehydration, lethargy and coma may be seen during attacks. Due to the rarity and often asymptomatic in the neonatal period it is not considered in the differential diagnosis by clinicians. Two cases (7-month-old male, 10-month-old girl) were accepted with lower respiratory tract infection findings. Sodium bicarbonate treatment was performed because metabolic disease was considered due to the presence of severe metabolic acidosis. Because of the inadequately to respond the treatmentfor the girl case, peritoneal dialysis was also performed, but severe neurological sequelae remained. Both cases were diagnosed with beta-ketothiolase deficiency by urine organic acid analysis. Patients were started with L-carnitine, and a protein-limited low-fatdiet was arranged. In lower respiratory tract infections accompanied by severe metabolic acidosis, beta-ketothiolase deficiency should also be considered.

Keywords

• Beta-ketothiolase defici-ency,metabolic acidosis,respiratory tract infection

Beta-ketotiyolaz Eksikliği: İki Vakanın Sunumu

Öz

Öz

Beta-ketotiyolaz (2-metilasetoasetil-CoA tiyolaz,T2) eksikliği izolösin ve keton metabolizmasının seyrek görülen, otozomal resesif geçiş gösteren bir bozukluğudur.  Hastalık ketoasidoz, kusma, dehidratasyon ve komaya kadar gidebilen klinik bulgular ile karakterizedir ve ataklarla seyretmektedir. Nadir görülmesi ve yenidoğan döneminde bulgu vermemesi nedeni ile çoğunlukla klinisyenler tarafından ayırıcı tanıda düşünülmemektedir. Alt solunum yolu enfeksiyonu bulguları ile başvuran 7 aylık erkek ve 10 aylık kıziki vakada ağır metabolik asidoz bulunması nedeni ile metabolik hastalık düşünülereksodyum bikarbonat tedavisi uygulanmıştır. Kız vakada tedaviye cevap alınamayarak periton diyalizi de uygulanmış ancak ağır nörolojik sekelli kalmıştır. Her iki vakada da idrar organik asit analizi ile beta-ketotiyolaz eksikliği tanısı konularak diyet önerileri ile birlikte karnitin tedavisi başlanmıştır. Ağır metabolik asidozun eşlik ettiği alt solunumyolu enfeksiyonlarında beta-ketotiyolaz eksikliğinin de düşünülmesi gereklidir.

Anahtar Kelimeler

• Beta-ketotiyolaz eksikliği,metabolik asidoz,solunumyolu enfeksiyonu

Kaynakça

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