OBJECTIVE: To evaluate the possible role of infectious agents on the occurrence of idiopathic sensorineural hearing loss (SNHL) in children. METHODS: This case control study was carried out at Rasul Hospital in Tehran, Iran from 2002-2003. We compared specific serum antibodies (IgG, IgM) measured by enzyme linked immunosorbent assay in 95 sensory hearing loss cases and 63 controls. RESULTS: Acute infections (IgM) detected in cases included: cytomegalovirus (CMV) 34.6%, toxoplasma 11.5%, mumps 8.7%, rubella 5.3%, and herpes simplex 5.3%. Previous infections (IgG) detected in cases included CMV 72%, herpes 6.6%, toxoplasma 26%, mumps 23.3%, and rubella 17.2%. Acute CMV and toxoplasma infections were more frequent in cases. Previous CMV, toxoplasma, rubella, and herpes infections were higher in controls. There was no significant difference for acute mumps, rubella, and herpes infections between cases and controls. CONCLUSION: These data are compatible with infectious agents having a significant role in the studied idiopathic SNHL cases, but association does not prove causation. We recommend specific drugs for confirmed active infections (CMV, toxoplasma, herpes) in idiopathic SNHL infants diagnosed before their first birthday. Mumps and rubella induced SNHL are preventable with routine vaccination.
OBJECTIVE: To evaluate the possible role of infectious agents on the occurrence of idiopathic sensorineural hearing loss (SNHL) in children. METHODS: This case control study was carried out at Rasul Hospital in Tehran, Iran from 2002-2003. We compared specific serum antibodies (IgG, IgM) measured by enzyme linked immunosorbent assay in 95 sensory hearing loss cases and 63 controls. RESULTS:Acute infections (IgM) detected in cases included: cytomegalovirus (CMV) 34.6%, toxoplasma 11.5%, mumps 8.7%, rubella 5.3%, and herpes simplex 5.3%. Previous infections (IgG) detected in cases included CMV 72%, herpes 6.6%, toxoplasma 26%, mumps 23.3%, and rubella 17.2%. Acute CMV and toxoplasma infections were more frequent in cases. Previous CMV, toxoplasma, rubella, and herpes infections were higher in controls. There was no significant difference for acute mumps, rubella, and herpes infections between cases and controls. CONCLUSION: These data are compatible with infectious agents having a significant role in the studied idiopathic SNHL cases, but association does not prove causation. We recommend specific drugs for confirmed active infections (CMV, toxoplasma, herpes) in idiopathic SNHL infants diagnosed before their first birthday. Mumps and rubella induced SNHL are preventable with routine vaccination.