Primary hydatid cyst of the diaphragm: A systematic review

Hydatid cysts of the diaphragm are rare, with limited information available regarding their presentation and management. Typically caused by Echinococcus granulosus, hydatid cysts most commonly affect the liver and lungs, while diaphragmatic involvement is unusual. This study aims to provide insight into this condition by reviewing documented cases in the literature. A comprehensive search was carried out on diaphragmatic hydatid cysts adhered to the following inclusion criteria: (1) the study included a case presentation detailing the patient's condition; (2) diagnostic modalities, surgical findings, or histopathology confirmed the diaphragmatic infection; (3) the cyst(s) originally arising from the diaphragm rather than merely transversing through it from neighboring structures. A total of 20 studies (28 patients) were included in this study. The mean age of patients was 36.4 years. Of the hydatid cysts identified, 13 (46.4%) were located on the right hemidiaphragm, five (17.9%) were located on the left, and four (14.3%) involved both sides of the diaphragm. Regarding size, four cysts (26.7%) measured ≤ 5 cm, two (13.3%) measured > 10 cm, and nine (60.0%) were between these dimensions. Correct preoperative localization of the primary diaphragmatic cyst was achieved in 9 patients (32.1%) and not achieved in 13 patients (46.4%). In conclusion, primary diaphragmatic hydatid cysts are often misdiagnosed as originating from adjacent structures based on imaging findings, with accurate localization typically achieved only during surgery. This condition appears to predominantly affect the right hemidiaphragm. Both thoracotomy and open abdominal approaches have demonstrated favorable outcomes in managing this rare entity.