A pediatric leukemia patient presented with fever and neutropenia, leading to the identification of an invasive Campylobacter jejuni strain causing bacteremia. Initial blood cultures grew Gram-negative rods, and further characterization revealed a hyper-aerotolerant C. jejuni, an unusual phenotype for this typically microaerophilic bacterium. This invasive strain was confirmed through whole-genome sequencing, highlighting its unique genetic adaptations. The patient was successfully treated with appropriate antibiotics. This case underscores the importance of considering atypical presentations of common pathogens in immunocompromised individuals and the utility of advanced diagnostic methods for characterizing unusual microbial traits.
Key note: Atypical pathogen phenotypes, like hyper-aerotolerance in C. jejuni, can cause severe invasive infections in immunocompromised patients, necessitating thorough diagnostic investigation.