Seven to 10 days (range 2–21 days) after a rat bite,
there is an abrupt onset of fever accompanied by chills, headache,
vomiting, muscle pain, and often, asymmetric polyarthritis4 that may
reflect sterile effusions or septic arthritis with S moniliformis present
in the joint fluid.5 Several days later there is
a maculopapular and sometimes petechial rash, which is most prominent
on the extremities, including the palms and soles.4 The
bite wound has usually healed and the site exhibits no or minimal
inflammation. Generalized adenopathy commonly occurs. Young children
often have diarrhea and weight loss. Many of the clinical features
are similar to Rocky Mountain spotted fever. Left untreated, the
infection follows a relapsing course lasting a mean of 3 weeks,
but may have a fatal outcome1,6 or result in arthritis
persistent for several months. Other reported manifestations include
septic arthritis without a rash,5 amnionitis, brain
abscess, disseminated fatal infection in infants, endocarditis,
hepatitis, meningitis, myocarditis, nephritis, and pneumonia.1,6Patients
with Haverhill fever exhibit fever, rash, and arthritis; vomiting
and pharyngitis are more prominent than in patients with rat-bite
fever.
Sodoku disease, due to S minus, has an incubation
period of 1 to 4 weeks. There is fever, ulceration at the previously
healed bite site, and regional lymphadenopathy. The fever may be
intermittent and associated with rash, with afebrile intervening
days. The infection responds rapidly to therapy with penicillin.1