Incisivo central único de la línea media del maxilar, holoprosencefalia y estenosis congènita del orificio nasal anterior en un recién nacido prematuro: a propósito de un caso / Solitary median maxillary central incisor, holoprosencephaly and congenital nasal pyriform aperture stenosis in a premature infant: case report

El síndrome del incisivo central único de la línea media del maxilar es un trastorno raro que implica anomalías de la línea media, como holoprosencefalia, anomalías de las fosas nasales, fisura palatina, labio leporino, hipotelorismo, microcefalia y panhipopituitarismo. La estenosis congénita del orificio nasal anterior es una causa mortal de dificultad respiratoria neonatal debido al estrechamiento del orificio nasal anterior, y podría confundirse con la atresia de coanas. En este informe, presentamos el caso de un recién nacido con síndrome del incisivo central único de la línea media del maxilar acompañado de otras anomalías, tales como holoprosencefalia, estenosis del orificio nasal anterior, microcefalia y panhipopituitarismo. El cariotipado mostró una deleción heterocigota en el gen SIX3 en la región 2p21, que produjo una forma más grave de holoprosencefalia.

Solitary median maxillary central incisor syndrome is a rare disorder involving midline abnormalities such as holoprosencephaly, nasal cavity anomalies, cleft palate-lip, hypotelorism, microcephaly, and panhypopituitarism. Congenital nasal pyriform aperture stenosis is a lethal cause of neonatal respiratory distress due to narrowing of the pyriform aperture anteriorly and it can be confused with choanal atresia. In this report, we present a newborn infant with solitary median maxillary central incisor syndrome accompanied by other abnormalities including holoprosencephaly, nasal pyriform aperture stenosis, microcephaly and panhypopituitarism. Chromosomal analysis showed heterozygous SIX3 gene deletion at 2p21 region resulting in a more severe form of holoprosencephaly.

A Case of Congenital Nasal Pyriform Aperture Stenosis

The cause of congenital nasal pyriform aperture stenosis is unclear. The development of the facial skeleton occurs between the fifth and the eighth week of gestation. It is at this stage that the stenosis occurs due to overgrowth of the ossification of the maxilla. Infants are obligate nasal breathers. Incomplete and milder forms of nasal airway obstruction may be present with mild respiratory distress, cyanosis, respiratory failure, asphyxia and eventual death. The diagnosis is done by CT, which demonstrates marked narrowing of the nasal inlet. Mild stenosis can be managed conservatively with humidification and topical decongestants but if conservative treatment fails, surgical intervention is candidate. We report a case of congenital nasal pyriform aperture stenosis. The patient, a 2-day old male neonate, had cyanosis during feeding and noisy breathing relieved by crying. His symptoms and signs were improved with surgical intervention without development disturbances.