A 48-year-old man from Mexico developed a serious fungal infection caused by Coccidioides, which spread from his lungs to his skin, bones, and joints, causing pain and swelling. Despite having a normally functioning immune system, he developed progressive disease that was initially misdiagnosed as rheumatoid arthritis. After switching to the antifungal medication fluconazole, his condition improved dramatically, with symptoms resolving within several months of treatment.