Treatment for ulcerative colitis often requires the administration of immunosuppressive therapy. Shortly after rescue therapy with infliximab for acute severe colitis, a patient who was also taking corticosteroids, azathioprine and adalimumab became rapidly unwell with atypical pneumonia, which did not respond to conventional antimicrobials. Re-examining the travel history revealed a prior caving trip to Costa Rica. Dimorphic fungal serology was thus tested and a diagnosis of paracoccidioidomycosis was made. After a lengthy intensive care unit admission, the patient made a recovery after the administration of appropriate antifungal therapy and was discharged home on long-term oral antifungals.