Infectious mononucleosis presenting as acute intermittent porphyria.

We have described a patient with infectious mononucleosis, confirmed by serologic studies, who had an initial episode of acute intermittent porphyria during the course of the infection. Although infections have been implicated in precipitating AIP, infectious mononucleosis has rarely, if ever, been described. A similar constellation of symptoms has been described for both infectious mononucleosis and AIP. Although infectious mononucleosis is a common infection, with 90% to 95% of the United States population showing seropositivity by adulthood, neurologic complications are uncommon. Acute intermittent porphyria should be considered in the differential diagnosis of patients with infectious mononucleosis, neuropathy, and abdominal pain.