Case Presentation: Coccidioidomycosis is a fungal infection caused by dimorphic fungus of Coccidioides species, endemic to the Southwest dry regions of the United States. Its usual presentation is community-acquired pneumonia. Less than 1% of cases present with disseminated infection which is more likely to occur in immunocompromised hosts. A 66-year-old man with no significant past medical history was transferred to our facility after being admitted to an outside hospital for six weeks due to cough and shortness of breath that started one month prior to admission. His symptoms were associated with fever, nausea, vomiting, and mid back pain. He lived in Austin, Texas but frequently traveled to Southern Texas. He was a lifetime non-smoker and had no exposure to animals or livestock. Initially he was found to have bilateral pleural effusions and pericardial effusion for which he required thoracentesis and pericardiotomy, respectively. Pleural and pericardial fluid analyses were unrevealing. Bronchoscopy and transbronchial biopsy were performed but did not reveal any evidence of malignancy. Bronchoalveolar lavage and tissue cultures were all negative. Despite multiple antibiotic courses for suspected pneumonia, he failed to improve and was subsequently transferred to our hospital. Upon arrival, he was afebrile but continued to have significant dyspnea and back pain. CBC and CMP were unremarkable. HIV Ag/Ab test and TB T-spot were negative. Pulmonary CT Angiography revealed multiple pulmonary emboli, multifocal airspace disease, and miliary nodularity throughout the lungs with confluent mediastinal lymphadenopathy. A lytic lesion was also present in T6 vertebral body which was confirmed by MRI of thoracic spine. These findings were highly concerning for metastatic disease.
The patient underwent bone biopsy of the lytic lesion and pathology revealed granulomatous inflammation and numerous spherules and endospores of Coccidioides immitis. Serum Coccidioides antibody by complement fixation was strongly positive with titer of 1:1024. He was diagnosed with disseminated coccidioidomycosis and intravenous liposomal amphotericin B was immediately started. At two weeks of therapy, a repeat Coccidioides antibody titer was 1:512. However, follow up MRI of thoracic spine showed a pathologic fracture of T6 with spinal cord compression prompting an urgent neurosurgical intervention for decompression. Culture of tissue obtained during surgery grew Coccidioides immitis. He was continued on long term liposomal amphotericin B and showed clinical improvement postoperatively.
Discussion: This case illustrates a disseminated coccidioidomycosis involving lungs, pleura, pericardium, lymph nodes, and bone simulating metastatic disease. Disseminated and severe infection, as in this case, is rare in immunocompetent patients and entails significant morbidity and mortality. Diagnosis can be challenging and in this case was possible by histopathology and serologic testing. Prolonged antifungal therapy may be required depending on severity of clinical manifestations and chronicity of infection.
Conclusions: Physicians should have high suspicion for endemic fungal infections, including coccidioidomycosis, in patients with subacute or chronic pulmonary findings and a pertinent travel history to the Southwest of the United States.