B72-19 The Dualism of Diagnoses: A Case of Pulmonary Cryptococcal Infection With Eosinophilia and Concomitant Primary Lung Adenocarcinoma

Abstract Introduction Cryptococcosis is an opportunistic fungal infection typically affecting immunocompromised patients (1). It is most commonly caused by Cryptococcus neoformans and Cryptococcus gattii, and it primarily affects the respiratory and central nervous systems (1). While uncommon, there are case reports describing cryptococcosis presenting with eosinophilia (2), as well as cryptococcosis diagnosed concurrently with lung cancer (3-5). Here, we present the case of a 50-year-old man with significant peripheral, pleural, and alveolar eosinophilia who was found to have cryptococcosis and concomitant metastatic lung adenocarcinoma as presenting diagnoses. Case Presentation A 50-year-old man from Honduras with no medical history presented to our facility with weight loss, cough, and hemoptysis for two weeks. Computed tomography (CT) of the chest showed diffuse bilateral nodular opacities and left hydropneumothorax. Labs revealed peripheral eosinophilia. He underwent left-sided chest tube placement with pleural fluid analysis showing 62% eosinophils; cultures and cytology were negative. He then underwent bronchoscopy with bronchoalveolar lavage (BAL) fluid showing 18% eosinophils and atypical cells suspicious for adenocarcinoma. Subsequent video-assisted thoracoscopic surgery with decortication and pleural biopsy confirmed metastatic primary lung adenocarcinoma. Fungal cultures from the BAL ultimately grew Cryptococcus neoformans; of note, serum cryptococcal antigen was negative. He was discharged on antifungal therapy with the intention to complete treatment before starting chemotherapy. Unfortunately, the patient returned four days later in fulminant shock and respiratory failure. Echocardiogram revealed new right ventricular failure and pulmonary hypertension. The patient was too unstable for imaging to evaluate for pulmonary embolism but was placed on empiric anticoagulation. A soleal deep vein thrombosis was noted on doppler study. Despite maximal support, he rapidly deteriorated and expired. Discussion Eosinophilia has been previously described as a paraneoplastic process of lung adenocarcinoma (6) as well as a manifestation of cryptococcus infection (2). This case represents the only report, to our knowledge, of peripheral, alveolar, and pleural eosinophilia accompanying de novo diagnoses of both cryptococcal infection and metastatic lung adenocarcinoma. The link between eosinophilia, lung adenocarcinoma, and cryptococcal infection remains incompletely understood and the presence of eosinophilia can raise suspicion for parasitic infection, eosinophilic pneumonia, and rheumatologic illness, which may lead to diagnostic delay (7). In patients with nodular/mass-like abnormalities on CT chest and peripheral, alveolar, or pleural eosinophilia, cryptococcal infection and malignancy should be strongly considered. Cryptococcosis should be excluded in patients with newly diagnosed lung adenocarcinoma and eosinophilia, as initiating chemotherapy in a patient with undiagnosed cryptococcosis could be fatal. This abstract is funded by: None