NAZAN ERSİN, FAHİNUR ERTUĞRUL, Aydın SARAÇ, Sema AYDOĞDU

Holoprozensefali : Bir olgu sunumu

Holoprozensefali, serebral hemisferlerin iki loba tam olarak ayrılamaması sonucu oluşan, ileri derecede fasiyal anomalilerle karakterize gelişimsel bir defekttir. Hastalık, şiddetine göre alobar, semilobar ve lobar tip olmak üzere üç gruba ayrılır. Siklopi ve premaksillanın agenezisi en şiddetli olgularda rastlanan fasiyal bulgular iken, mikrosefali ve hipoteleorizm hafif şiddetli olgularda rastlanır. Tek median maksiller santral kesici diş, dudak-damak yarığı, üst çenede frenulumun oluşmaması ve üst dudağın ark biçiminde olması da en sık gözlenen ağız ve diş bulgularıdır. Tek başına izole olabildiği gibi sendromlara da eşlik edebilen holoprozensefalinin prognozu, beyin ve fasiyal deformitelerin şiddetine ve ilgili anomalilerin varlığına bağlıdır. Hastaların çoğunda kromozomal bir anomali gözlenmemesine rağmen, bazı vakalarda otozomal dominant bir geçiş saptanmıştır. Maternal diabet, toksoplazmosis, hamilelikte geçirilen viral enfeksiyonlar ve kullanılan çeşitli ilaçların (fenitoin, salisilat içeren) risk faktörleri olabileceği bildirilmiştir. Bu çalışmanın amacı, semilobar holoprozensefali tanısı ile izlenen 5 yaşındaki bir kız çocuğunun orta hat defektlerini araştırmak ve literatür bilgilerinin ışığı altında hastalığı irdelemektir. Bu hastalıkta tek maksiller santral kesici diş, olguların erken dönemde saptanmasında bir ipucu olabilirken, hastalıktan kaynaklanan risklerin en aza indirilmesi ve genetik danışma verilmesi mümkün olabilecektir.

Anahtar Kelimeler:

Holoprosensefali, Çocuk, okul öncesi, Kadın, Kesici diş, Labial frenum

Holoprosencephaly: A case report

Holoprosencephaly which is characterized by severe facial anomalies is a developmental defect in which the cerebral hemispheres could not split sufficiently into two lobes. The disease can be graded into three as alobar, semilobar and lobar according to the degree of severity. Cyclopia and premaxillary agenesis are the facial findings of the most severe forms while microcephaly and hypoteleorism are the less severe facial anomalies. Solitary median maxillary central incisor, midline cleft palate, absence of the labial frenulum and arch-shaped upper lip are the most common dental findings. The prognosis of holoprosencephaly which could also be an isolated anomaly depends on the severity of the brain and facial deformities and associated anomalies. Although, the etiology in the majority of the cases does not exhibit chromosomal disorder, an autosomal dominant inheritance is observed in some families. Maternal diabetes, toxoplasmosis, viral enfection and various drugs (phenytoin and salicylates) used during pregnancy have been suggested as risk factors. The aim of the this study was to examine the midline defects of a 5 years-old girl who had been diagnosed as semilobar holoprosencephaly and discuss these findings in regard with the literature.

Keywords:

Holoprosencephaly, Child, Preschool, Female, Incisor, Labial Frenum,

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