Cerumen impaction was composed of abnormal exfoliation of keratinocytes that was correlated with infection.

OBJECTIVE

This study investigated the exact composition and tried to be helpful in explaining the etiologic mechanism of cerumen impaction in the external auditory canal (EAC).

METHODS

A hundred impacted cerumen samples and 15 normal cerumen samples were collected by manual removal and divided into 2 groups. All samples were examined via microbial culture, hematoxylin-eosin staining, periodic acid-Schiff staining, and fungal fluorescent staining.

RESULTS

Eighty-eight patients in group 1 were in the habit of using cotton buds. Forty-seven impacted cerumen samples tested positive for microbes, while only 1 sample of normal cerumen tested positive for microbes (p < .05). The most commonly isolated bacterium and fungus was Staphylococcus aureus and Aspergillus terreus respectively. All cerumen samples were composed of exfoliated keratinocytes and microorganisms assessed via pathologic examination. However, unlike normal cerumen, impacted cerumen contained nucleated keratinocytes and infiltrated neutrophils. Recurrent impaction was found only among patients who tested mold culture-positive.

CONCLUSION

Impacted cerumen is composed of abnormal exfoliated keratinocytes that was correlated with microbial-induced neutrophil-mediated inflammation. Mold infection is highly correlated with recurrent cerumen impaction. Microbial culture of removed impacted cerumen is strongly recommended. Ear cleaning with cotton buds, particularly when the EAC is wet might be one of the important causes of cerumen impaction which is need further studied.

LEVEL OF EVIDENCE: 2b.