Rat bite fever, a diagnostic challenge: case report and review of 29 cases

Abstract

Summary Rats can transmit Streptobacillus moniliformis, which may cause rat‐bite fever (RBF), a rare and potentially lethal zoonosis. Fastidious in vitro growth and unspecific symptoms, including fever, arthralgia, and polymorphous skin lesions, complicate the diagnosis. Rat‐bite fever follows exposure to contaminated bodily fluids of infected rodents; however, reports on Streptobacillus moniliformis‐related infections are few so far. A female patient presented with painful hemorrhagic pustules and purpuric lesions on hands and feet. She developed fever and migratory polyarthralgia. Blood culture yielded growth with Streptobacillus moniliformis. The patient owned rats and handled contaminated rat feces and urine, making this the most likely etiology of infection. We report a case of RBF due to Streptobacillus moniliformis in a rat handling‐patient. Difficulties in clinical and microbiological diagnosis highlight the need for a thorough and complete history‐taking and a greater understanding of this rare infectious disease.

Streptobacillus moniliformis Bacteremia in a Patient with Reactive Arthritis Without a Bite: A Case Report

“…As shown in the present case, this method accurately identified S. moniliformis. In our review of recent case report on RBF infections, we found most cases were identified by 16S-rRNA sequencing (2,6,11). The pathogen was not confirmed by sequencing analyses in the present case, which may be a limitation in the present case.…”

“…RBF is a low incidence of the disease with non-specific symptoms, as for this clinicist make a direct clinical diagnosis virtually impossible. In our review of case reports on RBF infections, we found in most cases accurate diagnostic delays caused up to seven days of significant delays to the initiating pathogen-specific therapy (6). More than 50% of patients with RBF develop migratory polyarthralgias, involving the small and large joints of the extremities (1) and may also be accompanied by septic arthritis (7).…”

“…Blood culture is the most important etiological method for diagnosing bloodstream infection and requires blood sampling prior to antibiotic administration. Unfortunately, blood culture tests might not be a sufficiently reliable diagnostic method, microbial culture failure rates of up to 33% (6). As a result, more rapid and definitive diagnosis method are highly anticipated.…”

“…Furthermore, reported cases without a bite history were up to 34 %. (6,13,16).Thus, we considered the possibility that she was infected through exposure to contaminated food or water. In a previous report, an outbreak of S. moniliformis blood stream infections was reported at a boarding school and led to the conclusion that it was transmitted through water that had been contaminated by rats (17).…”

“…Doxycycline, ceftriaxone and erythromycin are recommended for patients with penicillin allergy. In line with other physicians, we opted to begin a cephalosporinbased empirical therapy with Intravenous Ceftriaxone (6,18,19), and we adhered to the recommended treatment of penicillin G (19), after knowing the causative organism of RBF. However, continuation of a cephalosporin administration might be acceptable given the rare antibiotic resistance in Streptobacillus moniliformis (18).…”