Prodromal symptoms of listlessness, anorexia, and headache may be present. Most cases are self-limited. Complications include appendicitis, diffuse ulceration and inflammation of the small intestine and colon, peritonitis, meningitis, intussusception, and cholangitis. Pseudoappendicitis syndrome Characteristics include fever, abdominal pain, tenderness in the right lower quadrant, and leukocytosis. Pseudoappendicitis syndrome is caused by infection with Y pseudotuberculosis .
Infection causes mesenteric lymphadenitis with terminal ileitis.
Pseudoappendicitis syndrome is more common in older children and young adults. Physical findings mimicking appendicitis may be noted. Less commonly, pharyngitis, cellulitis, meningitis, conjunctivitis, pneumonia, arthritis, and erythema nodosum are seen. Fecal-oral transmission among humans has not been proven. Transmission via blood products has occurred.