Congenital hearing loss may either be permanent or sensori-neural or on occasion conductive or there may in fact be a combination of mixed conductive and sensori-neural hearing loss noted. The incidence of sensori-neural hearing loss is about 1 in 1000 infants and this doubles by age 2 and triples by age 3 with progressive hearing loss or acquired hearing loss due to meningitis or head injury or other causes. The cause of permanent hearing loss in 50% of cases is genetic and this may be due to various syndromes which may be dominant or inherited from the parents such as Treacher Collins’ Syndrome, Goldenhar Syndrome and Waardenburg Syndrome. (This is all on the website under Publications/Research on Clin Professor Coates’ Paediatric Otolaryngology Notes 2010), whilst in autosomal recessive sensori-neural hearing loss the hearing loss may skip a generation. This is seen in Usher Syndrome, Pendred Syndrome and Jervell-Lange Nielsen Syndrome. Non genetic causes of sensori-neural hearing loss may include a perinatal infection due to toxoplasmosis, rubella or cytomegalovirus, ototoxic medications, metabolic diseases, asphyxia or birth trauma, hyperbilirubenaemia, neonatal meningitis, prematurity and low birth weight or noise trauma. Children who have spent time in neonatal intensive care units are at a higher risk for sensori-neural hearing loss. All children can have a hearing test at any age utilizing objective means such as automated auditory brainstem screening (AABR), or otoacoustic emission screening. There are behavioural methods of testing for the older child and usually by age 4 the child is able to wear earphones and indicate the presence of sound on testing.

Congenital hearing loss may be static or occasionally the hearing loss can be progressive with children in some cases passing a newborn hearing screening test but later developing progressive permanent hearing loss. These children by virtue of the fact that they have learned speech before their hearing loss usually do very well with hearing aids or in some cases cochlear implants. Some parents, particularly those of deaf children where there is a hereditary component, prefer their child to learn AUSLAN which is an Australian sign language. There is strong evidence that picking up hearing loss within the first 6 months of life and management with either hearing aids or AUSLAN sign language enables the child to develop language at a similar rate to that of their normal hearing peers.