Methods
Initial laboratory investigations showed mild leukocytosis at 10.82 K/uL(normal range: 4.23-9.07 K/uL), elevated ESR at 78 mm/hr., elevated CRP at 19.2 mg/dl, and normal C3 and C4 levels. Hepatitis viral panel, HIV, and syphilis were non-reactive. PCR for respiratory viral infection and Neisseria and Chlamydia were all negative. A CT chest revealed a 1.5 cm spiculated nodule present in the posterior right lower lobe surrounded by ground-glass attenuation with an enlarged right hilar lymph node and a few sub-centimeter nodules in the right lower lobe (Fig 2.1). A CT-guided tissue biopsy of the peripheral lung nodule was performed for definitive diagnosis. Additionally, skin biopsies of the cutaneous manifestations were done. While anticipating the biopsy results, the patient’s rashes and painful swollen ankles gradually resolved on their own.
The pathological report of the lung biopsy demonstrated granulomatous inflammation with multinucleated giant cells and was negative for malignancy, raising suspicion for inflammatory processes which included fungal infection, tuberculosis, and sarcoidosis (Fig 3.1-3.2). The immunohistochemistry stains for CD68 highlighted histiocytes, and CK7 showed lung parenchyma around granulomas. GMS was negative for fungal infection and AFB was negative for mycobacteria (Fig 4). The skin biopsies showed significant papillary dermal edema with a mixed inflammatory infiltrate composed of lymphocytes and neutrophils, and direct immunofluorescence studies were all negative, consistent with Sweet’s syndrome.
Additional laboratory investigations including QuantiFERON TB, Aspergillus, Histoplasma, Blastomyces, Thermoactinomyces spp. , Saccharoplyspora rectivir, and Saccharomonospora viridis later returned negative. Coccidioides Ab Complement Fixation (CF) was positive with a titer of 1:16, yeast phase Ab titer of 1:32, and mycelial phase Ab <1:8. Antibody to TP antigen IgM, and antibody to F antigen IgG were also positive. The patient was diagnosed with pulmonary coccidioidomycosis associated with Sweet’s syndrome. Due to borderline Coccidioides CF (titer 1:16) and yeast phase Ab (titer 1:32), the infectious disease team recommended treating the infection as disseminated coccidioidomycosis with fluconazole 800 mg daily for at least 3 months even though there was no clinical evidence apart from yeast phase Ab titer of 1:32.