A 72-year-old man presented with a four-month history of progressive dyspnea, hemoptysis and weight loss. The patient was a resident of southwestern Ontario and had been travelling to Arizona annually for six years. He had a significant smoking history of 80 pack-years. Three years previously, he had a left upper lobe cavitary lung lesion diagnosed as a poorly differentiated bronchogenic carcinoma with coexistent blastomycosis. For treatment, a left upper lobectomy was performed and itraconazole was given for six months. One year before his current presentation, he had received an additional 12-month course of itraconazole therapy for recurrent pulmonary blastomycosis.
The patient’s most recent chest x-ray showed left pleural thickening, unchanged from three years previously. A presumptive diagnosis of recurrent bronchogenic carcinoma and/or blastomycosis was made, and the patient underwent investigation with fibre optic bronchoscopy.
On bronchoscopy, abnormal tissue was found invading the left lower lobe. Bronchoalveolar lavage (BAL), along with brushings and a biopsy, was performed. The bronchial washing smear showed atypical cells, interpreted as a poorly differentiated nonsmall cell carcinoma along with occasional organisms identified as Blastomyces species. The biopsy specimen showed atypical squamous epithelium and fungal organisms compatible with Blastomyces species, but no malignant cells were detected. Direct microscopy of the tissue biopsy, which was performed in the hospital microbiology laboratory using a calcofluor white preparation, showed the presence of a few spherules, suggestive of C immitis. A culture of the specimen grew C immitis. A nucleic acid probe (AccuProbe, Gen-Probe Inc, USA) further confirmed that the isolate was C immitis.
In light of the alternative diagnosis, the microscopic slides of the lung specimens obtained previously were re-examined. Periodic acid-Schiff and Gomori methenamine silver stains showed immature nonendosporulating cells and semi-mature spherules consistent with Coccidioides species (). Typical mature spherules of C immitis were not present, but showed individual, separately walled spherules adjacent to one another. There was no contiguity between adjacent cell walls, and no bud scars were present on the larger cells, as would be found with budding Blastomyces species ().
A bronchoalveolar lavage specimen stained with Gomori methenamine silver
A lung tissue sample containing budding Blastomyces species stained with Gomori methenamine silver
A 51-year-old man presented with right-sided pleuritic chest pain and cough five days after returning from a camping trip to the Grand Canyon (Arizona, USA). He was treated with an oral antibiotic for community-acquired pneumonia, based on his symptoms and an infiltrate on chest radiography. At follow-up, he complained of cough (only occasionally productive of clear sputum) and had no episodes of hemoptysis. He experienced intermittent fevers and chills, but no other systemic complaints or weight loss. He was previously well and on no regular medications. Baseline blood work including complete blood counts, electrolytes, creatinine and liver enzymes were normal.
A repeat chest radiography and high-resolution computed tomography of the chest showed an opacity in the periphery of the right upper lobe. There were no calcifications or cavitations within the lesion. He underwent bronchoscopy, with BAL, mediastinoscopy and biopsy. The organisms seen on the BAL smear were interpreted by a pathologist to be consistent with Blastomyces species. A culture of the specimen grew C immitis.
A three-month treatment with fluconazole 400 mg per day completely resolved the clinical symptoms and radiological findings.