Teenager gets rare rat-bite fever from pet rodent

A 17-year-old girl was infected with a rare, but treatable rat-bite fever, that developed from pet rodents living in her bedroom, reported the doctors who treated her.

Rat-bite fever has been reported in writings dating as far back as 2,300 years and originally described as a disease of the poor. But these days most of the cases occur among lab workers or in children with pet rodents, says an article published in the online journal BMJ Case Reports.

The condition often goes unrecognised and undiagnosed. Only 200 cases of rat-bite fever have been recorded in the US since 1839.

Most rat-bite fever cases involve a bite or scratch from a rodent, but there are several reports of infection without direct bacterial inoculation.

The young woman was admitted to hospital with pain in her right hip and lower back that had continued for two days and led to immobility.

Over the proceeding two weeks, she had an intermittent fever, nausea and vomiting, and a pink rash on her hands and feet.

Her nausea and vomiting improved, but the fever continued, and she had tenderness of a joint in her pelvis, and pain in her right leg.

The doctors learnt that the woman had numerous pets including a dog, cat, horse and three pet rats. The rodents lived in her bedroom. One of these rats had died three weeks prior to the onset of her symptoms.

A blood test returned positive for Streptobacillus moniliformis -- the most common cause of rat-bite fever.

The disease can have mortality as high as 13 percent, if left untreated. Fortunately, the woman underwent four weeks of antibiotics.

After five days, her rash and fever disappeared, and the joint pain in her pelvis improved over the following weeks. She made a full recovery.