The usefulness of routine histological examination of appendicectomy specimens in a South African tertiary centre

Background. It is accepted surgical practice to send all appendicectomy specimens for histological examination, but the usefulness and cost associated with this practice have not been established in our setting, a tertiary hospital in KwaZulu-Natal Province, South Africa (SA). Objectives. To determine the histological diagnoses of appendicectomy specimens in our centre, and the cost of identifying an alternative histological diagnosis requiring further treatment. Methods. Clinical data on patients undergoing appendicectomy for suspected acute appendicitis during the study period December 2012 - August 2015 were retrospectively retrieved from the hybrid electronic medical registry. Histological data were then extracted from the National Health Laboratory Service database. The cost of an appendicitis histology report was sourced from a private laboratory service. Results. A total of 290 patients were identified during the study period. Males had a significantly higher risk ( p <0.0001) than females of histologically confirmed appendicitis (odds ratio 3.2, 95% confidence interval 1.7 - 5.8). The negative appendicectomy rate was 22.4% (65/290). In 5.9% of specimens (17/290) an alternative diagnosis was made on histological examination, which influenced the management plan. These were parasitic co-infections in 13 cases (4.5%), premalignant conditions in 2 and tuberculosis in 2. The average cost of processing each appendicectomy specimen was ZAR871. The cost of identifying each patient with an alternative diagnosis that required treatment was ZAR14 858 ([290 × ZAR871]/17). Conclusions. This audit correlates with other SA studies showing that the aetiological differential for appendicitis is broad. Histological examination therefore remains critical in the management of patients with suspected acute appendicitis in our clinical setting.