Yersinia and viruses in acute non-specific abdominal pain and appendicitis.

Four out of 24 patients presenting as an emergency with acute non-specific abdominal pain showed serological evidence of infection with Yersinia pseudotuberculosis. Two out of 13 patients presenting with acute appendicitis during the same period also had evidence of Yersinia infection. Viral infection was present in only 1 patient in each group. Since it is rare to find antibodies to yersinia in healthy individuals, it seems likely that yersinia is a cause of some cases of non-specific abdominal pain. Viral infection does not appear to be an important aetiological factor in patients over 12 years of age.