Acute Invasive Pulmonary Aspergillosis in Immunocompetent Host Without Underlying Lung Disease

Abstract

INTRODUCTION: Aspergillosis is known to cause a wide range of clinical syndromes including invasive pulmonary aspergillosis (IPA) in immunocompromised patients. IPA has rarely been reported in immunocompetent patients; however, these cases were primarily associated with underlying lung disease. Here we present an unusual case of IPA in an immunocompetent host without known lung disease. CASE PRESENTATION: 34 year old caucasian male, plumber with four pack years history of smoking and no known medical problems developed productive cough, dyspnea, hemoptysis and wheezing after digging a ditch. Co-workers experienced similar symptoms but improved spontaneously after a few days. The patient was hospitalized due to worsening symptoms and subsequently managed in the ICU for severe hypoxemia requiring 100% oxygen supplementation via nonrebreather mask. He was started on intravenous antibiotics for pneumonia. Sputum culture was positive for aspergillus. Patient was empirically started on Voriconazole but absence of HIV and other risk factors prompted further evaluation to explore alternative etiologies. Fiberoptic bronchoscopy with bronchoalveolar lavage (BAL) and VATS were performed on the same day. BAL cultures were positive for aspergillus. Histopathology and GMS stain were consistent with invasive, hemorrhagic aspergillosis. Antibiotics were discontinued and voriconazole was continued. The patient improved slowly and was finally discharged home. DISCUSSION: Conditions that compromise the immune system predispose patients for IPA. AIDS, organ rejection, immunosuppressive therapy, neutropenia, utilization of high dose corticosteroids and underlying lung disease are the classic risk factors for IPA. Upto 78% mortality has been reported with IPA and may occur without dissemination. A positive predictive value of sputum and BAL cultures for IPA depends upon host condition and prevalence of aspergillus in the area . Our patient did not have known underlying lung disease or immunocompromised status; however history suggested significant exposure to the fungus. Positive sputum and BAL cultures, lung biopsy proven histological findings and fungus isolated in tissue confirmed the diagnosis of IPA. Since IPA is extremely rare in immunocompetent normal hosts there are no specific guidelines regarding duration of antifungal therapy. CONCLUSIONS: Although IPA is associated with specific risk factors, our case highlights the importance of considering this diagnosis even in immunocompetent hosts with no underlying lung disease in an appropriate clinical scenario.