Case Report of A Novel C.1341 Delt Homozygous Mutation in The HEXB Gene in A Girl with Photosensitive Seizure

Öz

Sandhoff disease is one of the rare lysosomal storage diseases with autosomal recessive inheritance. The progressive neurological decline and the appearance of a cherry red spot on the macula is typical. Diagnosis is confirmed by a decrease in total β-hexosaminidase A and B enzyme activities and by showing the mutation in the HEXB gene. A 14-month-old girl was referred to our clinic for developmental delay and the appearance of a cherry red spot on the macula. It was learned that she was the only child of parents who had first degree relatives among them, she had no head and neck control and did not recognize the mother. In the neurological examination, there was no eye contact and head-neck control. She had excessive irritation against noise and hypotonicity. Hepatosplenomegaly was not detected. In the enzyme study, Total β-Hexosaminidase A and B 29 nmol / hour / mg protein (N: 1223 ± 273 nmol / hour / mg protein) and in the HEXB gene study c.1341delT homozygote mutation was detected. The patient was diagnosed with Sandhoff disease, the family was informed about the disease and genetic counseling. Unilateral photosensitive seizure and electroencephalography revealed focal findings. In this case, the importance of diagnosis of ocular examination in patients with suspected metabolic disease; It was aimed to draw attention to the fact that Sandhoff disease may also be observed with atypical findings.

Anahtar Kelimeler

• Sandhoff disease,Cherry red spot in macula,focal EEG sign,photosensitive seizure

HEXB Geninde Yeni Bir C.1341delt Homozigot Mutasyonu Saptanan Fotosensitif Nöbetli Bir Kız Çocuğu Vakası

Öz

Sandhoff hastalığı otozomal resesif geçişli, nadir rastlanan lizozomal depo hastalıklarından biridir. Progresif nörolojik gerileme ve makulada kiraz kırmızısı nokta (Cherry red spot) görünümü tipiktir. Total β-hekzosaminidaz A ve B enzim aktivitelerinde azalmanın ve HEXB geninde mutasyonun gösterilmesi ile tanı doğrulanır. 14 aylık kız hasta gelişme geriliği ve makulada kiraz kırmızısı nokta görünümü saptanması üzerine yönlendirildi. Öyküsünden aralarında birinci dereceden akrabalık olan anne babanın tek çocuğu olduğu, baş boyun kontrolünün hiç olmadığı, anneyi tanımadığı öğrenildi. Hastanın nörolojik muayenesinde göz teması ve baş boyun kontrolü yoktu. Sese karşı aşırı irkilmesi ve hipotonisitesi mevcuttu. Hepatosplenomegali saptanmadı. Enzim çalışmasında Total β-Hekzosaminidaz A ve B 29 nmol/saat/mg protein (N: 1223±273 nmol/saat/mg protein), genetik çalışmasında HEXB geninde c.1341delT homozigot mutasyonu saptandı. Hastaya Sandhoff hastalığı tanısı konuldu, aileye hastalık hakkında bilgi ve genetik danışma verildi. İzleminde tek taraflı fotosensitif nöbet ve elektroensefalografide fokal bulgu saptandı. Bu olgu ile metabolik hastalık şüphesi olan hastalarda göz dibi muayenesinin tanıda önemine; Sandhoff hastalığının atipik bulgular ile de seyredebileceğine dikkat çekilmek istenmiştir.  

Anahtar Kelimeler

• Sandhoff hastalığı,makulada kiraz kırmızısı nokta görünümü,fotosensitif nöbet,ketojenik diyet

Kaynakça

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