Moraxella peritoneal dialysis-related infections: a systematic review

Moraxella species, although infrequent in peritoneal dialysis (PD)-associated infections, are established pathogens. Moraxella catarrhalis is recognized as a cause of upper and lower respiratory tract infections and is increasingly associated with β-lactamase production. The role of Moraxella species in PD-related infections warrants further investigation.

A comprehensive search of PubMed and Google Scholar was conducted for cases of PD-associated infections caused by Moraxella. Inclusion criteria required a diagnosis of peritonitis or exit-site infection confirmed by culture. Demographic data, clinical presentation, microbiological identification, antimicrobial resistance, therapeutic regimens, and outcomes were analyzed.

Fourteen cases of Moraxella-related peritonitis in PD patients were identified between 1987 and 2024 from 13 studies, with no reports of exitsite infections. The mean age was 56 years; diabetic nephropathy was the most common underlying condition (four cases). M. catarrhalis (n = 6) and Moraxella osloensis (n = 5) were the most frequent pathogens. The most commonly reported methods were bacterial growth in culture media, followed by species identification using biochemical profiling or automated systems (n = 10), and advanced confirmatory techniques. Clinical presentation included abdominal pain, fever, and clouding of the dialysis fluid. Most isolates were susceptible to cephalosporins, aminoglycosides, and fluoroquinolones. The majority of patients (86%) retained their catheters after appropriate treatment, usually with intraperitoneal cephalosporins, achieving complete symptom resolution within a few days. Overall prognosis was favorable, with no mortality.

Moraxella species, although rare, should be considered in the differential diagnosis of PD-associated infections. Identification using advanced techniques allows effective treatment and favorable outcomes, often without the need for catheter removal.