A 62-year-old British man with advanced HIV was established on antiretroviral therapy and treatment for disseminated Mycobacterium avium complex and Cytomegalovirus infections. One month later he re-presented with epigastric pain, an epigastric mass and skin lesions. Abdominal imaging revealed large volume lymphadenopathy, which was not present on previous imaging. Blood cultures yielded Penicillium marneffei, a dimorphic fungus endemic to South-east Asia. The patient had spent several years travelling in Thailand prior to the diagnosis of HIV. Penicilliosis is a common AIDS-defining illness in endemic areas, but remains rare in Europe. In this case, it presented in the context of a rapidly decreasing viral load as an immune reconstitution inflammatory syndrome. The challenges of management in the context of multiple comorbidities and polypharmacy are discussed.