Male, 3 months old, fifth gestation, mother 34 years old and father 39 years old, not consanguineous. History of maternal aunt with epilepsy and older brother of 6 years with autism. Normal pregnancy and term birth by caesarean section due to pelvic presentation, without postnatal complications.
He was referred to the outpatient paediatric plastic surgery department for presenting nasal breathing difficulties due to obstruction of the right nostril by a polyp, as well as a pedunculated intraoral mass in the upper gum between 2 labial frenulae. Normal brain, no hypertelorism, epiphora of the right eye, high palate, well formed uvula and palate.

Computerised axial tomography (CAT) of the skull and facial mass revealed agenesis of the corpus callosum together with a hypodense image in the interhemispheric line at the level of the frontal horns, corresponding to a lipoma with irregular borders measuring 3.8 x 2.1 x 1.7 cm; spina bifida occulta at the level of the cervical spine and central fissure at the level of the maxillary arch.

The electroencephalogram was within normal limits for the patient's age, with no evidence of paroxysmal activity or lesion focus.
We performed surgical spindle resection of both the single nasal polyp (irregularly shaped, lobulated, measuring 0.9 x 0.7x 0.5 cm) and the intraoral polyp (measuring 2 x 1 x 0.7 cm). The anatomopathological study reported keratinised squamous polyps with the presence of pilosebaceous adnexa and fibroadipose tissue, with few mucinous glands and no immature or malignant components.

The outpatient follow-up of the patient up to the age of 1 year and 8 months at the time of publication of this article has been favourable and without complications. Neurologically, despite presenting agenesis of the corpus callosum, he remains alert with psychomotor development in accordance with his age and without seizures. The chromosomal study was male 46 XY with normal karyotype.