BACKGROUND: Biotherapies targeting TNFalpha were proven to be effective in the most severe cases of Crohn's Disease, a chronic granulomatous inflammatory bowel disease that can involve any portion of the digestive tract. The tolerance of anti-TNFalpha therapy is usually good, although several infectious complications have been reported with these drugs. METHODS: We report a case of a Crohn's disease patient who developed pulmonary cryptococcosis following chicken manure exposition while he received adalimumab and azathioprine. CASE: A 54-year-old man, with history of severe Crohn's disease and ankylosing spondylitis, was admitted for diarrhea and abdominal pain under azathioprine treatment. In December 2010, he was treated with oral prednisone (1 mg/kg/day), but Crohn's disease relapsed when prednisone dose was lower than 30 mg/a day. The patient was then treated with adalimumab, but six weeks later he developed severe pulmonary cryptococcosis. The patient experienced a good outcome under antifungal therapy. We retrospectively found a high exposure to chicken manure in the last weeks. CONCLUSION: Cryptococcosis is an opportunistic infection that can occur under anti-TNFalpha therapy. The environmental exposure to Cryptococcus spp. (in particular in chicken manure) is a source of contamination. Avoiding exposition to bird manure should be a recommendation for patients who are living in rural areas.