Prevalence of sensorineural hearing loss due to toxoplasmosis in Saudi children: a hospital based study.

A survey to identify the aetiology of hearing impairment among Saudi children was carried out. Children were divided into 2 groups according to presence or absence of laboratory evidence of toxoplasmosis "at risk' and "not at risk.' Serological tests for toxoplasmosis were done to 1054 children. We found positive IgM antibody against Toxoplasma gondii in the blood of 70 of the 1054 children (6.6%) (age ranged between 12 months and 14 years). Forty nine of the seventy infected children (70%) were found to have bilateral sensorineural hearing loss (11 of 19 children of the at risk group and 38 of 51 from the "not at risk' group). Hearing impairment was bilateral in all cases profound in 9, moderate to severe in 29 and mild in 11. Known causes of hearing impairment were excluded. The high prevalence of hearing impairment among children due to toxoplasmosis is presented.