Emerging Insights into Corynebacterium Kroppenstedtii Complex Associated Breast Abscesses: A Retrospective Study

Sreethish Sasi,1 Manal Mahmoud Mohamed Hamed,2 Hamad Elnil Abdelgabar Abdel Hadi,1 Wael Goravey,1 Emad Ibrahim,2,3 Fatma Ben Abid,1,4 Sanjay Doiphode,2 Godwin Wilson,2 Adila Shaukat Ali Kashaf,5,6 Muna Al-Maslamani,1,5 Abdullatif Al-Khal1 1Infectious Diseases Division, Department of Medicine, Communicable Diseases Center, Hamad Medical Corporation, Doha, Qatar; 2Division of Microbiology, Department of Laboratory Medicine and Pathology, Hamad Medical Corporation, Doha, Qatar; 3Biomedical Research Center, Qatar University, Doha, Qatar; 4Weill Cornell Medical College, Doha, Qatar; 5College of Medicine, Qatar University, Doha, Qatar; 6Infectious Diseases Division, Department of Medicine, Al-Wakra Hospital, Hamad Medical Corporation, Doha, QatarCorrespondence: Sreethish Sasi, Infectious Diseases Division, Department of Medicine, Communicable Diseases Center, Hamad Medical Corporation, Doha, Qatar, Tel +974- 50290089, Email [email protected]; [email protected]: Corynebacterium kroppenstedtii complex (CKC), including C. kroppenstedtii, C. parakroppenstedtii, and C. pseudokroppenstedtii, has been implicated in breast abscesses and granulomatous mastitis, presenting diagnostic and therapeutic challenges. Its lipophilic nature and association with specific populations necessitate targeted investigations.Materials and Methods: This retrospective study was conducted at Hamad Medical Corporation, Qatar, including all CKC isolates from breast tissue collected between October 2016 and March 2024. Data from electronic medical records were collected and anonymized. Microbiological analysis involved standard culture techniques, Matrix-Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry (MALDI-TOF MS) for identification, and antibiotic susceptibility testing per Clinical and Laboratory Standards Institute (CLSI) standards. Statistical methods included descriptive analyses, Pearson’s correlation, and relative risk calculations.Results: Among 34 isolates, 31 were from breast tissue of pre-menopausal women, predominantly obese or overweight, with a median age of 33 years. Breast abscesses were typically unilateral, associated with axillary lymphadenopathy, and varied in size and complexity. Recurrence within six months occurred in 58% of cases. Prolonged antimicrobial therapy and, in some cases, surgical intervention were necessary. Most isolates were sensitive to vancomycin, linezolid, and rifampicin, but resistance to penicillin and daptomycin was noted.Conclusion: CKC is an emerging pathogen in breast abscesses, requiring precise diagnostic approaches and individualized treatment strategies. Advanced genomic tools are recommended for species differentiation and resistance monitoring. Ongoing research is essential to optimize management and address rising antimicrobial resistance.Keywords: Corynebacterium kroppenstedtii, breast-abscess, granulomatous mastitis, hyperprolactinemia, lipophilic bacteria, antimicrobials, microbiological analysi