Clinicopathological Review of Human Coenurosis in Kwazulu-Natal, South Africa: A Retrospective Single Center Study.

Background: To describe the clinicopathological features of human coenurosis diagnosed at a single center in an academic Anatomical Pathology Laboratory, KwaZulu-Natal, South Africa. Methods: This was a 10-year retrospective laboratory based study, from 2011-2020, which reappraised the clinical presentation, histomorphological tissue reaction patterns and outcomes in patients diagnosed with coenurosis. Results: Five cases of coenurosis and 19 cases of cysticercosis were diagnosed during the study period. Following re-appraisal of the slides, 6 cases of coenurosis were confirmed and included in the study cohort. The anatomical distribution of disease was as follows: brain (1), liver (1), eye (1) and soft tissue (3). There were 3 males and 3 females and the patients' age ranged from 2 to 46 (mean 22.2) yr. Three patients were HIV positive whilst the clinical history of the infection was not available for the other 3 patients. All patients presented with mass effect related symptoms, ranging from headache to a painful soft tissue swelling. Two cases displayed synovial metaplasia in addition to characteristic chronic subacute inflammation and fibrosis. One case had supportive inflammation. Two cases comprised of coenuri exclusively and therefore it was not possible to assess tissue reaction. Conclusion: We describe the first cases of human coenurosis in HIV positive patients and for the first time report synovial metaplasia as one of the reaction patterns of coenurosis. Whenever cysticercosis and hydatidosis are considered clinically, a negative serology should prompt clinicians to consider coenurosis in addition to the neoplastic diagnostic considerations.