Pulmonary Hydatid Disease with Aspergillosis - An Unusual Association in an Immunocompetent Host

Aspergillus Coinfection in a Hydatid Cyst Cavity of Lung in an Immunocompetent Host: A Case Report and Review of Literature

Aspergilloma (a saprophytic infection) typically colonizes lung cavities due to underlying diseases such as tuberculosis, bronchiectasis, cavitary lung cancer, sarcoidosis, and pulmonary infarctions. Rarely, aspergilloma has been noted within a hydatid cyst. Even if this was the case, it is more common to find the coexistence of aspergilloma and pulmonary echinococcal cysts in immunocompromised individuals. It is, however, very uncommon to find this coinfection in normal immune status individuals. Here, we report on the successfully treated case of a 30-year-old immunocompetent female from Western Nepal with histologically proven coinfection by these two pathogens. She had a prolonged history of exposure to domesticated dogs. She suffered from hemoptysis from time to time for 3 years with increased frequency in the last 30 days. She was misdiagnosed clinically during a past medical visit at a local health center. Her computed tomography (CT) scans showed well-defined nonenhancing cystic lesions in the anterior basal segment of the right lower lobe adjacent to the major fissure. She underwent enucleation of the cyst via right posterolateral thoracotomy. On further histopathological evaluation, laminated membranes of the ectocyst along with fungal elements were found, and periodic acid-Schiff (PAS) staining revealed Aspergillus in the form of septate hyphae and acute angle branching. Owing to patient's economic constraints and unavailability in our center, DNA testing and molecular characterization could not be performed which further highlights the essence of diagnosing and managing such cases in resource poor settings. Eventually, we reviewed 12 confirmed cases of this coinfection in immunocompetent individuals during a period of 7 years (2015-2022) comparing them to a systematic review of 22 confirmed cases of the same coinfection from 1995 to 2014.

Concomitant of Pulmonary Hydatid Cyst and Aspergilloma: A Rare Coinfection

The coexistence of cystic echinococcosis (CE) and aspergilloma is rather uncommon. Aspergillus species, saprophytic fungi, can colonize pulmonary cavities that are caused by tuberculosis, sarcoidosis, and CE. Infection by Aspergillus is often occurring in immunosuppressed patients. However, coinfection of aspergilloma with pulmonary hydatid cyst is very unusual, especially in an immunocompetent patient with unruptured cyst. Herein, we report a case of lung hydatid cyst coinfected with Aspergillus in a 42-year-old Iranian man from Southern Iran. Chest X-ray and computed tomography (CT) scan showed a circumscribed cystic lesion in the superior and inferior segment of the lower lobes of right and left lungs that suggests hydatid cyst. Radical surgery (lobectomy) was performed for the patient. Histopathological evaluation reconfirmed the classical laminated layer of hydatid cyst. Moreover, the ectocyst layer of the right lung showed the presence of numerous cluster septate hyphae with acute-angled branching, as seen in the morphology of Aspergillus species. DNA was extracted from the cyst, and the ITS1-5.8s-ITS2 region of the fungal agent was amplified. Sequencing and analysis of seminested PCR product revealed that the isolate has the most similarity with Aspergillus niger. Further attention is recommended to control fungal pathogens during pulmonary hydatidosis. The coexistence of aspergilloma should always be kept in mind for the better management of CE.