Granulomatous disorders like sarcoidosis or Crohn's disease are commonly associated with extrapulmonary or extraintestinal manifestations which occasionally may represent the only symptoms. We describe a 28-year-old female patient suffering from atypical erythema nodosum and arthritis. Although the chest x-ray was unremarkable bronchoalveolar lavage revealed lymphocytic alveolitis with an elevated CD4/CD8 ratio of 8 and 11.4 at repeated examinations suggesting a diagnosis of sarcoidosis. Further diagnostic workup included endoscopy of the bowel. The macroscopic aspect and histology of the terminal small bowel and colon ascendens indicated Crohn's disease. The patient recovered on steroids and sulfasalazine. Six months later she developed a perianal abscess for which she needed surgery supporting the diagnosis of Crohn's disease. This is the first case of a significantly (>6) elevated CD4/CD8 ratio in Crohn's disease previously regarded as highly specific for sarcoidosis.