# Aetiology

Aetiology

Non-syndromic cleft lip and/or palate may present as new diagnosis within a family or with a clear family history . A family history of  cleft lip and palate in which a first-degree relative is a ff ected increases the risk of  subsequent cleft cases in the family , supporting the theory that there are underlying genetic mutations contributing to the aetiology . Isolated cleft palate is more commonly associated with a syndrome than cleft lip and palate and isolated cleft lip. Over 150 named syndromes are associated with cleft lip and palate, although Stickler (ophthalmic and musculoskeletal abnormalities), DiGeorge (cardiac/thymic anomalies), Down, Apert and Treacher Collins syndromes are most frequently encountered. aetiology of  cleft lip and/or palate, including maternal epilepsy (and associated medication) and drugs (e.g. steroids, diazepam, sodium valproate and phenytoin). The role of  antenatal folic acid supplements in preventing cleft lip and/or palate remains equivocal. Pierre Robin sequence is a condition worth considering in specific terms. This sequence comprises isolated cleft palate, retrognathia and a posteriorly displaced tongue (glossoptosis), w hich is associated with early airway and feeding di ffi culties. Although airway obstruction does not commonly occur in babies with a non-syndromic cleft lip and/or palate, in babies with an airway obstruction, e.g. Pierre Robin sequence hypoxic episodes during sleep and feeding can be life-threat ening. Intermittent airway obstruction is more frequent and is managed conservatively . In more severe cases the children will often require adjunctive support for their airway compro mise suc h as supplemental oxygen, nasopharyngeal airway and even tracheostomy . More controversially , surgical adhesion of the tongue to the lower lip (labioglossopexy) in the first few da ys after birth is an alternative but less commonly practised method of  management. Mandibular distraction surgery has advocates but numerous attempts at developing a consensus view in support of  this procedure for airway compromise in cleft have been unsuccessful. Summary box 50.2 Aetiology of cleft lip and palate /uni25CF /uni25CF /uni25CF 

The cause of cleft lip and/or palate is multifactorial
Most cases occur without a clear family history or known risk
factors
Clefts can be associated with many craniofacial/medical
syndromes