Corynebacterium minutissimum usually presents with erythrasma, a macular rash, but rarely it can cause extracutaneous infections such as endocarditis, peritonitis, pyelonephritis, and catheter-related bloodstream infections. Here, we present the first case of septic arthritis caused by C. minutissimum and a literature review of invasive C. minutissimum infections. The diagnosis was confirmed by the patient's clinical findings and microbiological examination of the joint fluid. Considering the patients hemodialysis catheter and the pathogenic nature of the C. minutissimum, we strongly suspected a catheter-related infection. Clinical and laboratory follow-ups showed consistent improvement with treatment, characterized by reduced pain, swelling, and localized warmth in the left knee, along with a significant decline in acute-phase reactants. The patient achieved full recovery following a four-week course of antibiotics and catheter removal. Our report emphasizes the importance of not disregarding the isolation of non-diphtheria Corynebacterium from appropriately collected sterile samples in symptomatic patients, particularly those with indwelling devices. Based on this case report, clinicians should consider the rare possibility of this microorganism being the cause of septic arthritis.
Keywords: Corynebacterium minutissimum; Corynebacterium non-diftheriae; indwelling device; infection; septic arthritis.
Corynebacterium minutissimum is a bacteria that usually causes a mild skin infection called erythrasma. In rare cases, it can cause infections in other parts of the body, such as kidney infection, heart valve infection, and bloodstream infection. This report discusses the first known case of a joint infection caused by this bacterium. The diagnosis was made by examining the patient’s symptoms and testing fluid from the affected joint. During follow-up, complaints of pain, swelling, and increased warmth in the left knee regressed. Laboratory values returned to normal. The patient recovered completely after 4 weeks of antibiotic treatment and removal of the catheter. This report highlights the importance of not ignoring this type of bacteria in clinical samples from patients, especially those with medical devices like catheters. Physicians should be aware that, although rare, this bacterium can cause joint infections.