Histoplasmosis Mistaken for Lung Neoplasm During Immunosuppression Therapy

Background TNFα antagonists such as Cimzia use large immunogenic protein molecules to induce deviations in normal host immunity and inflammatory response. Most warnings address alert providers to seriously consider initiating immunologics, because TNF plays an important role in immunity, notably against mycobacteria. Cimzia is different than other prior agents targeting TNF, because it does not fix, complement or induce cell-mediated cytotoxicity that is antibody-dependent from not having an immunologic Fc portion. Case information A sixty year-old female with psoriasis, hypertension and greater than fifteen year history of Crohn's disease on Cimzia presented after four months of cough, night sweats, weight loss and generalized weakness. Her productive chronic cough evolved from brownish and bloody phlegm to a greenish color. Initial imaging from her PCP revealed a right upper lung mass thought to be a malignant tumor. Social history did not endorse any use of tobacco products or prior history of COPD, asthma or pneumonia. Family history for cancer was unremarkable. Patient describes that she was a teacher for many years in an older school building that had multiple past infestations, including possum. The initial attempt at bronchoscopy was inadequate for pathology, but repeated procedure denoted an exophytic and fungating mass. Cardiothoracic surgery performed an elective right partial right pneumonectomy and mediastinoscopy. Pathology performed on brushings were negative for malignancy, but endorsed a granuloma with acute inflammation. Final biopsy from the procedure revealed a granulomatous inflammation with a methenamine silver stain revealing histoplasmosis. Urine histoplasma antigen was negative, but antibody was high at 1:1, which can be seen with disseminated or diffuse pulmonary histoplasmosis. Patient began a short inpatient course of liposomal Amphotericin B transitioning to oral itraconazole prior to discharge. Conclusions Histoplasmosis mimics many common respiratory infections and neoplastic processes with symptom presentation and radiologic findings that have led to surgical resections of non-malignant pulmonary granulomatous nodules initially thought to be carcinomas. Patients on certolizumab should be closely monitored for the development of disseminated disease such histoplasmosis and warned about participating in activities that can expose them to inhalation of airborne microconidia.