Diagnosis of granulomatosis with polyangiitis - is it that difficult? / Nabia Idaam Mustapa Albakari

GPA is a rare disease with reported annual incidence and prevalence is estimated 23.7-156.5 per million and 3.0-14.4 per million, respectively (1). GPA is more common in European populations and slightly more in male with male to female ratio 1.5: 1 (2). It may occur at any age but typically at age 35-55 years old. It classically involved upper and lower respiratory tract and glomerulonephritis. According to American College of Rheumatology (ACR) classification the diagnosis is made when 2 out of 4 criteria are present, which includes nasal or oral inflammation, abnormal chest radiograph, urinary sediment and granulomatous inflammation on biopsy. This test has a sensitivity of 88.2 percent and specificity of92 percent.
Otological manifestation are found in 19 to 61 percent of cases with GP A (3 ). The commonest presentation is otitis media ( 4). It is due to eustachian tube dysfunction caused by nasopharyngeal involvement but commonly misdiagnosed as infection (5). Up to 50 percent of GPA cases presented with hearing loss ( 6). Bakthavachalam et al reported that both sensorineural and conductive hearing loss are common in GP A (7). However, audiogram was not done for our patient to determine the type of hearing loss.