The Differential Diagnosis for Pneumonia in the Immunocompromised: A 64-Year-Old Male With Cough and Fever.

SESSION TITLE: Infectious Disease Student/Resident Case Report Posters IISESSION TYPE: Medical Student/Resident Case ReportPRESENTED ON: Tuesday, October 28, 2014 at 01:30 PM - 02:30 PMINTRODUCTION: The differential diagnosis for immunocompromised patients presenting with pulmonary infiltrates is wide; both non-infectious causes, such as drug-related or pulmonary hemorrhage, should be considered in addition to infectious etiologies, including atypical bacteria, viruses and fungi.

CASE PRESENTATION: A 64 year old male with past medical history significant for renal transplant performed in 2009 reported to the ED complaining of fever and cough productive of yellow sputum. On arrival, the patient was afebrile with a heart rate of 86 beats/min, BP of 144/63 mm Hg, respiratory rate of 18, and an oxygen saturation of 88%. Physical examination was significant for a raised, non-erythematous lesion at the left medial canthus and bilateral crackles throughout the posterior lung fields. WBC count was 23, 600/μL. CT revealed a right upper lobe alveolar consolidation, as well as bilateral innumerable pulmonary nodules (figure 2). Ocular exam showed multiple white lesions located both superiorly and inferiorly to the disc in the bilateral retina. Bronchoscopy revealed numerous pearly endobronchial nodules in the right mainstem and the right upper lobe bronchi. Biopsies of the endobronchial nodule and canthus lesion returned positive for broad based budding yeast .

DISCUSSION: The lungs are the most common site of organ involvement with Blastomycosis dermatitidis infection. Eye involvement is extremely rare, and is found in less than one percent of cases. Blastomycosis infection often presents as an acute pneumonia; patients can also develop chronic pneumonia, similar in presentation to bronchogenic carcinoma, tuberculosis, or other fungal infections. To confirm diagnosis, bronchoalveolar lavage and/ or tissue biopsy must demonstrate the presence of dimorphic fungus. Serodiagnosis is of limited usefulness due to significant cross reactivity between blastomycosis and other fungi. Although there have been previous reports of pulmonary blastomycosis presenting as a cobblestone appearance on bronchoscopy, to our knowledge, this is the first case of blastomycosis causing endobronchial nodules. The choice of proper antifungal therapy depends on the severity of disease as well as the immune status of the patient. Our patient developed severe ARDS and was mechanically ventilated for eight days. He was treated with amphotericin B, and will continue with fluconazole for one year, as fluconazole has ocular penetration. With this regimen, he reported significant clinical improvement, with complete recovery of his respiratory function and vision.

CONCLUSIONS: Our case demonstrates the importance of a broad differential diagnosis, including atypical causes, for immunocompromised patients with pulmonary infiltrates. Bronchoscopy should be pursued early, as it can be invaluable in diagnosis. Reference #1: Saeed, A, Williams, A, Bradley, R, et al. Bronchoscopic View of Pulmonary Blastomycosis J Bronchol Intervent Pulmonol 2009; 16: 266-269. Reference #2: DISCLOSURE: The following authors have nothing to disclose: Kiruba Vembu, Vijaya Sivaling Ramalingam, Andreea Antonescu-TurcuNo Product/Research Disclosure Information.