Student research award 1993: Characteristics of cerumen in diabetic patients: a key to understanding malignant external otitis?

Abstract

Malignant externa otitis is a potentially fatal disease in diabetic and other immunocompromised patients. Cerumen contains defense properties that protect the patient against infection. We tested the hypothesis that patients with diabetes mellitus have abnormalities in their cerumen that affect the environment of their external auditory canals and may predispose them to malignant externa otitis.

Malignant External Otitis: Review and Personal Experience

“…The male to female ratio has been reported to range from 1.8 : 1 to 18 : 1 (15,16). The reason for the high proportion of male sufferers is largely unknown: some authors think that it may depend on weaker antibacterial activity due to the lower degree of acidity in the earwax of males (19).…”

“…It has been hypothesized that in diabetic patients, the increased virulence of germs in the EAC is fostered by particular biochemical characteristics of the earwax, since its lower acidity, reduced concentration of lysozyme, and the augmented ratio between saturated and unsaturated fatty acids could impair local antibacterial activity (19).…”

Malignant Otitis Externa

“…Patients who have diabetes show poor chemotaxis and phagocytosis of polymorphonuclear leukocytes, monocytes, and macrophages, leading to susceptibility to P aeruginosa infection [21,22]. Another contributing factor may be the higher pH of cerumen in individuals who have diabetes [23].…”

External otitis: A challenge in management

“…It tends to have a pH of 7.4 rather than the usual pH of 6.1. As noted earlier, a pH of 7.4 is conducive for maximal growth of most of the causative organisms of external otitis [53]. Thus, an important normal host defense mechanism is nonfunctional.…”