Rare UTI: Rodentibacter pneumotropicus Infection Case Report

A rare instance of a urinary tract infection (UTI) caused by the bacterium Rodentibacter pneumotropicus, formerly known as Pasteurella pneumotropica, has been documented in an immunocompetent patient. This case, reported in June 2025 in the American Journal of Case Reports, highlights the importance of considering less common pathogens when diagnosing UTIs, even in individuals with healthy immune systems.

From Pasteurella to Rodentibacter: A Taxonomic Shift

The bacterium in question underwent a reclassification following advancements in genetic and phenotypic analyses. What was previously categorized as Pasteurella pneumotropica is now recognized as Rodentibacter pneumotropicus. This change reflects a better understanding of the genetic diversity and evolutionary relationships within the pneumotropica complex, resolving issues of misclassification and providing a more accurate framework for studying the organism’s epidemiology and clinical relevance.

Atypical Presentation in Mexico

The case involved a 37-year-old male patient in Mexico who initially presented with gastrointestinal symptoms, including diarrhea. He subsequently developed urinary issues following a ureteroscopy – a procedure to remove stones from the urinary tract. Despite initial treatment with meropenem and paracetamol, the patient experienced persistent fever and leukocytosis (an elevated white blood cell count, indicating infection). A urine culture ultimately revealed the presence of R. Pneumotropicus.

Diagnosis and Treatment

The laboratory initially identified the bacterium as P. Pneumotropica, but further analysis confirmed it as R. Pneumotropicus. Importantly, the isolated strain was sensitive to fluoroquinolones. The patient underwent a transurethral resection of the prostate and was then successfully treated with ciprofloxacin, leading to resolution of his symptoms.

Rodentibacter pneumotropicus: A Respiratory Resident

R. Pneumotropicus is a Gram-negative bacterium commonly found in the respiratory tracts of mammals, particularly rodents. While it rarely infects humans, this case demonstrates its potential to cause UTIs, even in individuals without compromised immune systems. A separate case, documented in a Wednesday Slide Conference on March 26, 2025, also identified R. Pneumotropicus in a rat alongside Mycoplasma sp., indicating its presence as a resident bacterium in rodent respiratory flora.

Implications for Clinical Practice

The rarity of this infection underscores the need for clinicians to consider a broader range of pathogens when diagnosing UTIs. The case highlights that relying solely on commonly identified UTI-causing bacteria may lead to delayed or incorrect treatment. Precise identification and sensitivity testing are crucial for guiding effective antibiotic therapy. The authors of the case report emphasize that this finding provides evidence supporting the ability of R. Pneumotropicus to cause infection in humans, even in the absence of underlying immunocompromise.

Beyond the Urinary Tract: Potential for Pulmonary Infection

While this report focuses on a urinary tract infection, the case involving the rat suggests a potential link to pulmonary infections. In that instance, large numbers of R. Pneumotropicus were isolated from the lungs, alongside Mycoplasma sp., indicating a possible role in suppurative pneumonia and bronchiectasis. This suggests that R. Pneumotropicus may present with varied clinical manifestations depending on the site of infection.

Looking Ahead

Further research is needed to understand the prevalence of R. Pneumotropicus infections in humans and to determine the risk factors associated with infection. The reclassification of this bacterium and the increasing recognition of its potential to cause disease emphasize the importance of ongoing surveillance and accurate microbiological identification in clinical settings. As of today, February 5, 2026, this remains a rare but noteworthy finding in the spectrum of uropathogens.