Yersinia pseudotuberculosis as the cause of septicaemia in a patient with amyloidosis.

Septicaemia caused by Y. pseudotuberculosis in a female patient, aged 61, is reported. The patient suffered from amyloidosis with extensive infiltration of liver, spleen, and kidneys. While under treatment with corticosteroids and azathioprin, Y. pseudotuberculasis, serotype IA, was isolated from each of 6 blood cultures. The infection responded favourably to treatment with ampicillin. The development of Y. pseudotuberculosis septicaemia owing to impairment of the defence mechanisms by the underlying disease and the treatment given is discussed.