Rat bite fever (Streptobacillus moniliformis) with septicemia in a child

Management Strategies for Common Animal Bites in Pediatrics: A Narrative Review on the Latest Progress

Animal bites are a common reason for children to visit primary care and emergency departments. Dog bites are the most prevalent, followed by cat bites at 20-30%. Other animals such as bats, monkeys, snakes, and rats collectively contribute less than 1% of cases. Hospitalization is necessary in only 4% of animal bite incidents. The main aim of this narrative review is to summarize the main protocols currently followed in pediatrics in cases involving the most common bites from different animal species. Analysis of the literature showed that the management of common animal bites in children presents a multifaceted challenge requiring a comprehensive understanding of the epidemiology, clinical presentation, and treatment modalities associated with each specific species. Effective wound management is paramount in reducing the risk of infection and promoting optimal healing outcomes. Additionally, tetanus vaccination status should be assessed and updated as necessary, and prophylactic antibiotics may be indicated in certain cases to prevent secondary infections. Furthermore, the role of rabies prophylaxis cannot be overstated, particularly in regions where rabies is endemic or following bites from high-risk animals. In addition to medical management, psychosocial support for both the child and their caregivers is integral to the overall care continuum. Future studies exploring the efficacy of novel treatment modalities, such as topical antimicrobial agents or advanced wound dressings, may offer new insights into optimizing wound healing and reducing the risk of complications.

Streptobacillus moniliformis right hand abscess and monoarthritis following a rat bite

Streptobacillus moniliformis is a zoonotic agent associated with rat bites. We present a patient with cellulitis, subcutaneous abscess, and septic mono-arthritis after a rat bite of the right hand. The patient had no systemic features of rat bite fever (RBF). S. moniliformis was cultured from purulent drainage of a thumb abscess. This case illustrates an unusual clinical presentation of streptobacillary infection after a rat bite.

A real-time multiplex PCR assay for detection of the causative agents of rat bite fever, Streptobacillus moniliformis and zoonoticStreptobacillus species

Rat bite fever (RBF) caused by Streptobacillus moniliformis has been described as a diagnostic challenge. While it has a favorable prognosis with treatment, timely diagnosis is hindered by the lack of culture-free identification methods. Here we present a multiplex real-time PCR assay that detects the zoonotic Streptobacillus spp. as well as differentiate the primary causative agent of RBF, Streptobacillus moniliformis. The performance of this assay was evaluated using mock clinical specimens for blood, serum, and urine. Analytical sensitivity was determined to be 3-4 genome equivalents (GE)/µl for the zoonotic Streptobacillus spp. target, and 1-2 GE/µl for the S. moniliformis specific target. The assay correctly detected only the intended targets with no cross-reactivity identified. The pathogen was detected in all spiked matrices and not detected in the negative non-spiked specimens. This rapid diagnostic assay may permit quicker diagnosis of RBF patients.

Rat-Bite Fever in the United States: An Analysis Using Multiple National Data Sources, 2001-2015

BACKGROUND

Rat-bite fever is a rare disease associated with rat bites or direct/indirect rodent contact.

METHODS

We examined rat-bite fever and rat-bite injury diagnoses in the United States during 2001-2015. We analyzed national, state, and Indian Health Service healthcare encounter datasets for rat-bite fever and rat-bite injury diagnoses. We calculated average-annual encounter rates per 1 000 000 persons.

RESULTS

Nationally, the rat-bite fever Emergency Department visit rate was 0.33 (95% confidence interval [CI], 0.19-0.47) and the hospitalization rate was 0.20 (95% CI, 0.17-0.24). The rat-bite injury Emergency Department visit rate was 10.51 (95% CI, 10.13-10.88) and the hospitalization rate was 0.27 (95% CI, 0.23-0.30). The Indian Health Service Emergency Department/outpatient visit rate was 3.00 for rat-bite fever and 18.89 for rat-bite injury. The majority of rat-bite fever encounters were among individuals 0-19 years of age.

CONCLUSIONS

Our results support the literature that rat-bite fever is rare and affects children and young adults. Targeted education could benefit specific risk groups.

Streptobacillus canis sp. nov. isolated from a dog

From a phlegmon in a dog an aerobic and facultatively anaerobic, indole-, oxidase- and catalase-negative, non-motile bacterium was isolated in 2019 in Germany that stained Gram-negative and showed a pleomorphic, rod-shaped, non-spore-forming appearance. Based on the results of 16S rRNA gene sequence analyses, strain IHIT1603-19^T was assigned to the genus Streptobacillus with sequence similarities of 98.6, 98.0, 97.9, 97.1 and 94.4 % to the type strains of Streptobacillus felis, Streptobacillus notomytis, Streptobacillus ratti, Streptobacillus moniliformis and Streptobacillus hongkongensis, respectively. Strain IHIT1603-19^T could also clearly be differentiated from other Streptobacillus species by rpoB, groEL and recA gene, nucleotide and amino acid sequence analyses as well as by core genome phylogeny. Regarding DNA-DNA relatedness, strain IHIT1603-19^T demonstrated an average nucleotide identity of 83.00 and 82.28 % compared to S. felis 131000547^T and S. moniliformis DSM 12112^T, respectively. Chemotaxonomic and physiological data of strain IHIT1603-19^T were in congruence with other closely related members of the family Leptotrichiaceae, represented by highly similar enzyme profiles and fatty acid patterns. MALDI-TOF MS analysis also proved suitable in unequivocally discriminating strain IHIT1603-19^T from all currently described taxa of the genus Streptobacillus. On the basis of these data, we propose the novel species Streptobacillus canis sp. nov. with the type strain IHIT1603-19^T (=DSM 110501^T=CCUG 74118^T=CIP 111795^T). The G+C content of the DNA of the type strain is 26.6 mol%, genome size is 1.60 Mbp.

Near-fatal Periprosthetic Infection with Streptobacillus moniliformis: Case and Review

Case presentation of a 66 year old female with penicillin hypersensitivity, who suffered late acute periprosthetic infection of her total knee replacement. After emergency surgery and admission to intensive care, the responsible organism was later identified as Streptobacillus moniliformis. This serves as the first documented case of Streptobacillus moniliformis prosthetic joint infection. As standard culture mediums provide an exceedingly low detection rate, 16S PCR should instead be used as the first line method of identification. As a result, its detection is largely dependent on clinicians recognising relevant factors within the patient's history, namely close contact with rodents. In a patient with penicillin hypersensitivity, carbapenems have demonstrated potential as an effective treatment strategy.

A rare cause of vertebral osteomyelitis: the first case report of rat-bite fever in Portugal

Rat-bite fever is a rarely diagnosed illness caused by Streptobacillus moniliformis . Although this disease is distributed worldwide, there have been few cases reported in Europe. Here, we report a case of vertebral osteomyelitis and sternoclavicular septic arthritis caused by S. moniliformis in a Portuguese patient previously bitten by a rat. Laboratory diagnosis was performed using molecular identification. This is the first case report of rat-bite fever in Portugal. The case described here serves as a reminder for physicians to consider this diagnosis in patients who have developed fever syndromes after being in contact with rodents.

Streptobacillus notomytis sp. nov., isolated from a spinifex hopping mouse (Notomys alexis Thomas, 1922), and emended description of Streptobacillus Levaditi et al. 1925, Eisenberg et al. 2015 emend

A pleomorphic, Gram-negative, rod-shaped, indole-, oxidase- and catalase-negative, non-spore-forming, non-motile bacterium was isolated in 1979 from the heart of a spinifex hopping mouse (Notomys alexis Thomas, 1922) with septicaemia and stored as Streptobacillus moniliformis in the strain collection of the Animal Health Laboratory, South Perth, Western Australia (AHL 370-1), as well as under CCUG 12425. On the basis of 16SrRNA gene sequence analyses, the strain was assigned to the genus Streptobacillus, with 99.4 % sequence similarity to the type strain of Streptobacillus moniliformis, 95.6 %sequence similarity to the type strain of Streptobacillus hongkongensis and 99.0 %sequence similarity to the type strain of Streptobacillus felis. The clear differentiation of strain AHL 370-1T from Streptobacillus moniliformis, Streptobacillus hongkongensis and Streptobacillus felis was also supported by rpoB, groEL and recA nucleotide and amino acid sequence analysis. Average nucleotide identity was 87.16 % between strain AHL 370-1T and Streptobacillus moniliformis DSM 12112T. Physiological data confirmed the allocation of strain AHL 370-1T to the family Leptotrichiaceae, considering the very similar profiles of enzyme activities and fatty acids compared to closely related species. Within the genus Streptobacillus,isolate AHL 370-1T could also be separated unambiguously from the type strains of Streptobacillus moniliformis, Streptobacillus hongkongensis and Streptobacillus felis by MALDI-TOF mass spectrometry. Two further strains (KWG2 and KWG24) isolated from asymptomatic black rats in Japan were highly similar to AHL 370-1T. On the basis of these data, we propose the novel species Streptobacillus notomytis sp. nov., with the type strain AHL370-1T (=CCUG 12425T=DSM 100026T=CCM 8593T=EF 12425T).

Approved and novel strategies in diagnostics of rat bite fever and other Streptobacillus infections in humans and animals

Rat bite fever (RBF), a worldwide occurring and most likely under-diagnosed zoonosis caused by Streptobacillus moniliformis, represents the most prominent disease of Streptobacillus infections. Recently, novel members have been described, from which a reservoir in rats and other animal species and a zoonotic potential can be assumed. Despite regularly published case reports, diagnostics of RBF continues to represent a 'diagnostic dilemma', because the mostly applied 16S rRNA sequence analysis may be uncertain for proper pathogen identification. Virtually nothing is known regarding prevalence in humans and animal reservoirs. For a realistic assessment of the pathogen's spread, epidemiology and virulence traits, future studies should focus on the genomic background of Streptobacillus. Full genome sequence analyses of a representative collection of strains might facilitate to unequivocally identify and type isolates. Prevalence studies using selective enrichment mechanisms may also enable the isolation of novel strains and candidate species of this neglected group of microorganisms.

Oceanivirga salmonicida gen. nov., sp. nov., a member of the Leptotrichiaceae isolated from Atlantic salmon (Salmo salar)

A pleomorphic, Gram-negative, rod-shaped, indole-, oxidase- and catalase- negative, non-spore-forming, non-motile bacterium was originally isolated in 1992 from moribund, seawater farmed Atlantic salmon with multifocal tissue necrosis. Strain AVG 2115T displayed considerable similarities with Streptobacillus moniliformis, one of the two etiological agents of rat bite fever, and has been stored as Streptobacillus sp. NCIMB 703044T. On the basis of 16S rRNA gene sequence analyses, this strain displayed >99 % sequence similarities with uncultured bacterial clones from the digestive tracts of marine mammals, followed by Sneathia sanguinegens CCUG 41628T (92.7 %), 'Sneathia amnii' Sn35 (92.5 %), Caviibacter abscessus CCUG 39713T (92.2 %), Streptobacillus ratti OGS16T (91.3 %), Streptobacillus notomytis AHL 370-1T (91.2 %), S. moniliformis DSM 12112T (91.0 %), Streptobacillus felis 131000547T (90.9 %) and Streptobacillus hongkongensis DSM 26322T (89.7 %). Sequence similarities to all other taxa were below 89 %. Phylogenetic analysis for strain NCIMB 703044T revealed highly similar results for gyrB, groEL and recA nucleotide and deduced amino acid sequence analyses independent of the employed treeing method. Average nucleotide identities (ANI) for complete genomes ranged from 66.00 % to 72.08 % between strain NCIMB 703044T and the type strains of Sebaldella termitidis, Leptotrichiabuccalis, Streptobacillus moniliformis, Sneathia sanguinegens and Caviibacter abscessus. Chemotaxonomic and physiological data of strain NCIMB 703044t were in congruence with closely related members of the family Leptotrichiaceae, represented by highly similar enzyme profiles and fatty acid patterns. MALDI-TOF MS analysis was capable to clearly discriminate strain NCIMB 703044T from all currently described taxa of the family Leptotrichiaceae. On the basis of these data we propose the novel taxon Oceanivirga salmonicida gen. nov. sp. nov. with the type strain AVG 2115T (=NCIMB 703044T) (=DSM 101867T). The G+C content is 25.4 %, genome size is 1.77 Mbp.

Streptobacillus ratti sp. nov., isolated from a black rat (Rattus rattus)

An indole-, oxidase- and catalase-negative, non-motile bacterium, strain OGS16T, was isolated from an oral swab of a feral black rat (Rattus rattus) in 2007 in Japan. It stained Gram-negative and had pleomorphic, rod-shaped, non-spore-forming cells. Based on 16S rRNA gene sequence analyses, strain OGS16T was assigned to the genus Streptobacillus, with 16S rRNA gene sequence similarities of 99.3, 99.0, 98.6 and 95.5% to the type strains of Streptobacillus moniliformis, Streptobacillus notomytis, Streptobacillus felis and Streptobacillus hongkongensis, respectively. Strain OGS16T could also be differentiated clearly from other species of the genus Streptobacillus by rpoB, groEL and recA nucleotide and deduced amino acid sequence analysis. DNA-DNA relatedness as obtained by average nucleotide identity was 89.10% between strain OGS16T and Streptobacillus moniliformis DSM 12112T. Chemotaxonomic and physiological data for strain OGS16T were congruent with results for other closely related members of the family Leptotrichiaceae, represented by highly similar enzyme profiles and fatty acid patterns. MALDI-TOF MS analysis also proved suitable in discriminating strain OGS16T unequivocally from all currently described taxa of the genus Streptobacillus. On the basis of these data, we propose the novel species Streptobacillus ratti sp. nov., with the type strain OGS16T (=JCM 31098T=DSM 101843T). The G+C content of the DNA of the type strain is 25.9 mol% and the genome size is 1.50 Mbp.

Phenotypic and Genotypic Characteristics of Members of the Genus Streptobacillus

The genus Streptobacillus (S.) remained monotypic for almost 90 years until two new species were recently described. The type species, S. moniliformis, is one of the two etiological agents of rat bite fever, an under-diagnosed, worldwide occurring zoonosis. In a polyphasic approach field isolates and reference strains of S. moniliformis, S. hongkongensis, S. felis as well as divergent isolates were characterized by comparison of molecular data (n = 29) and from the majority also by their physiological as well as proteomic properties (n = 22). Based on growth-independent physiological profiling using VITEK2-compact, API ZYM and the Micronaut system fastidious growth-related difficulties could be overcome and streptobacilli could definitively be typed despite generally few differences. While differing in their isolation sites and dates, S. moniliformis isolates were found to possess almost identical spectra in matrix-assisted laser desorption ionization-time of flight mass spectrometry and Fourier transform infrared spectroscopy. Spectroscopic methods facilitated differentiation of S. moniliformis, S. hongkongensis and S. felis as well as one divergent isolate. Sequencing of 16S rRNA gene as well as functional genes groEL, recA and gyrB revealed only little intraspecific variability, but generally proved suitable for interspecies discrimination between all three taxa and two groups of divergent isolates.

Rat bite fever

Rat bite fever (RBF) is a bacterial zoonosis for which two causal bacterial species have been identified: Streptobacillis moniliformis and Spirillum minus. Haverhill fever (HF) is a form of S. moniliformis infection believed to develop after ingestion of contaminated food or water. Here the infectious agents, their host species, pathogenicity (virulence factors and host susceptibility), diagnostic methods, therapy, epidemiology, transmission and prevention are described. Special emphasis is given on information from the field of laboratory animal microbiology and suggestions for future research.

Detection of Streptobacillus spp. in feral rats by specific polymerase chain reaction

Streptobacillus moniliformis is an etiological agent of rat-bite fever and Haverhill fever in human infection. As the currently available methods for identifying the causative bacteria are not satisfactory, we attempted to establish them by PCR using newly designed primers for the 16S rRNA gene of S. moniliformis. We then determined the prevalence of Streptobacillus spp. in two species of feral rats that inhabit an urban region in Japan, because information on the prevalence of the bacteria in feral rats is obscure. The use of PCR with newly designed primers showed that an extremely high proportion of R. norvegicus harbored the bacteria (61/66, 92%), whereas the prevalence was only 58% in R. rattus (30/52). The nucleotide sequence analysis of the 16S rRNA gene of Streptobacillus spp. isolated from oral swabs of feral rats showed at least two different types of bacteria among isolates from R. norvegicus and R. rattus.

Streptobacillus moniliformis as the causative agent in spondylodiscitis and psoas abscess after rooster scratches

We report a case of Streptobacillus moniliformis spondylodiscitis accompanied by a psoas abscess in an 80-year-old man scratched by a rooster. S. moniliformis was identified from abscess fluid by use of 16S rRNA gene sequencing. After 18 weeks of antimicrobial therapy, the clinical condition of the patient improved.

Streptobacillus moniliformis septic arthritis: a clinical entity distinct from rat-bite fever?

BACKGROUND

Streptobacillus moniliformis is a zoonotic agent associated with rodent contacts. Although it is more commonly reported to cause rat-bite fever with reactive arthritides, it can also lead to pyogenic infection of the joints.

CASE PRESENTATION

We present a lady with past history of osteoarthritis developing streptobacillary septic arthritides of the right knee and left wrist, and required antibiotic and arthrotomy for treatment. We also review 11 previously reported cases of streptobacillary septic arthritis to discuss the characteristics, treatment, prognosis of the infection, and illustrates the differences between streptobacillary rat-bite fever and septic arthritis. Among this patient population, most patients had potential contact with rats (91.6%). The knee is the most commonly affected joint (58.3%), and 83.3% patients having polyarticular involvement. As opposed to rat-bite fever, fever and rash was only present in 58.3% and 16.7% of patients respectively. S. moniliformis bacteremia is uncommon (8.4%) and the prognosis is good.

CONCLUSION

Arthrocentesis is useful in distinguishing streptobacillary septic arthritis from reactive arthritis of rat-bite fever. The sole use of commercial media containing sodium polyanethol sulfonate may render the bacterial culture negative. A detailed history of possible exposure to rodents should be elicited from patients with arthritis in order to facilitate microbiologic diagnosis.

Rat bite fever and Streptobacillus moniliformis

Rat bite fever, caused by Streptobacillus moniliformis, is a systemic illness classically characterized by fever, rigors, and polyarthralgias. If left untreated, it carries a mortality rate of 10%. Unfortunately, its nonspecific initial presentation combined with difficulties in culturing its causative organism produces a significant risk of delay or failure in diagnosis. The increasing popularity of rats and other rodents as pets, together with the risk of invasive or fatal disease, demands increased attention to rat bite fever as a potential diagnosis. The clinical and biological features of rat bite fever and Streptobacillus moniliformis are reviewed, providing some distinguishing features to assist the clinician and microbiologist in diagnosis.

Rat-bite fever in children: case report and review

We report 2 cases of rat-bite fever (RBF), a multisystem zoonosis, in children and review the literature. RBF is caused by I of 2 Gram-negative organisms: Streptobacillus moniliformis or, less commonly, Spirillum minus. Both of our cases developed in school-aged girls with a history of rat exposure who presented with a multisystem illness consisting of fever, petechial and purpuric rash, arthralgia and polyarthritis. Both responded promptly to antibiotic treatment. An additional 10 cases from a MEDLINE review (1960-2000) are reviewed. RBF must be included in the differential diagnosis of febrile patients with rashes and a history of exposure to rats.

Streptobacillus moniliformis: case report and review of the literature

Streptobacillus moniliformis is one of the causes of rat bite fever. The clinical and microbiological diagnosis of this rare infectious disease is often quite problematic. Penicillin, in sufficiently high dosis, is the treatment of choice and leads to a prompt resolution of the infection, whereas lack of treatment leads to a 13% mortality rate. As far as we know, this paper reports the first human isolate in Belgium.

Streptobacillus moniliformis infection: 2 cases and a literature review

Two cases of Streptobacillus moniliformis infection are reported in farmers bitten by rats during their work. One patient had a subcutaneous abscess requiring surgical treatment and the other streptobacillary rat bite fever. Streptobacillus moniliformis was isolated from pus and blood, respectively. An erythromycin course failed to eradicate the infection in the first patient. Both patients were successfully treated with penicillin.

Rat bite fever in a pet lover

Rat-bite fever is an uncommon bacterial illness resulting from infection with Streptobacillus moniliformis that is often transmitted by the bite of a rat. The cutaneous findings in rat-bite fever are nonspecific but have been described as maculopapular or petechial. We describe a 9-year-old girl with acrally distributed hemorrhagic pustules, fever, and arthralgias. Diagnosis was delayed because of difficulty in identifying the pathologic organism. She was successfully treated with 10 days of ceftriaxone.