Marrow-middle ear connections: A potential cause of otogenic meningitis

Hypothesis: We hypothesize that the connections between the hematopoietic bone marrow and middle ear is a potential cause of childhood otogenic meningitis. Background: Although it is known that there is a causal relationship between otitis media and bacterial meningitis, the relationship has never been satisfactorily established. Human fetal and infant temporal bones prepared for light microscopic evaluation revealed direct connections between the hematopoietic bone marrow and middle ear. We noted this difference in anatomy between the infant middle ear and the adult middle ear. Methods: We studied 10 temporal bones from 5 infants in each group: meningitis group with otitis media who died of meningitis, control Group 1 without otitis media, and control Group 2 with otitis media who died of diseases other than meningitis. A quantitative analysis of the frequency of connections between the hematopoietic bone marrow and middle ear was performed. The correlation between unabsorbed mesenchyme and otitis media also was investigated. Results: The frequency of connections was significantly higher in order of the meningitis group, control Group 2, and control Group 1. The degree of unabsorbed mesenchyme tended to be more severe in order of the meningitis group, control Group 2, and control Group 1. Conclusion: The prevalence of connections between the hematopoietic bone marrow and middle ear in patients with meningitis and otitis media is high. A higher prevalence of connections in infants with otitis media could increase the risk for otogenic meningitis in them.