[External auditory canal cholesteatoma with chronic renal failure or hemodialysis]

External auditory canal cholesteatoma (EACC) is a rare otologic disease, characterized by focal osteonecrosis, sequestration and overlying epithelial loss of the bony external auditory canal (EAC). The etiology and pathogenesis of EACC remain controversial. There are only 2 reports on the association between EACC and chronic renal failure (CRF)/hemodialysis (HD). METHOD & RESULT: (1) This study reviewed seven EACC cases with CRF. The mean age was 68.4 years (range: 56 -81 years), and the male-female ratio was 5:2. There were 12 ears with EACC (5 cases were bilateral and 2 cases were unilateral). The EACCs were found in the inferior or posterior inferior part of the EAC in 11 ears. The number of the ears in stage III or IV was 6. Five cases were on HD. (2) Seventy-six cases with CRF on HD were examined for EACC, and 2 out of those 70 cases were diagnosed as having EACC. (3) A comparative study of the 7 EACC cases on HD and 68 non-EACC cases on HD revealed no significant differences in the sex, age, period on CRF/HD, complications (diabetes mellitus or skin disease), smoking, ear cleaning and the use of an earphone or a hearing aid.

Six out of all 9 EACC cases with CRF developed bilaterally, and in the inferior or posterior inferior part of the EAC, which implies a common pathological condition that contributes to the development of EACC. The mean age of 9 patients with EACC was relatively older (66.7 years), therefore age-related changes in the EAC are suspected in the cases with CRF on HD. The patients with CRF on HD have a high incidence of EACC. This strongly suggests the association between EACC and CRF/HD, but the mechanism of this pathogenesis has not been revealed.