Introduction: Carbapenem-resistant Klebsiella pneumoniae (CRKP) infections pose a serious challenge, particularly in pediatric transplant recipients, who are at increased risk due to prolonged immunosuppression. The OXA-48 and NDM-1 carbapenemase genes confer resistance to most beta-lactam antibiotics, including carbapenems, which are often the last-resort treatment. Managing these infections in children remains difficult due to limited data and fewer antibiotic options. Fosfomycin, though less commonly used in pediatrics, has gained interest for its broad spectrum, safety, and synergy with other antimicrobials. This case report details the successful management of a 12-year-old pediatric renal and liver transplant recipient with an OXA-48 and NDM-1-producing Klebsiella pneumoniae infection. The patient was treated with fosfomycin leading to complete clinical recovery and negative follow-up cultures.
Case Report: A 12-year-old female with a diagnosis of oxalosis underwent liver transplantation in February 2024 and kidney transplantation in July 2024 from living related donors. Post-transplantation, her recovery was uneventful until the second month following the kidney transplant, when she presented with fever and abdominal pain. Urine culture revealed Klebsiella pneumoniae at 100,000 CFU/ml, which was later identified as OXA-48 and NDM-1 positive, indicating the presence of carbapenemase-producing genes, which contributed to resistance against ESBL. Antibiotic therapy was adjusted, and the patient was started on a combination of fosfomycin (50 mg/kg every 8 hours) and meropenem, guided by susceptibility testing. However, an extended biogram later confirmed meropenem resistance, leading to its discontinuation, and treatment continued with fosfomycin monotherapy. After 14 days of treatment, the patient showed significant clinical improvement, with resolution of fever and normalization of acute phase reactants. She was discharged on oral fosfomycin therapy, and follow-up cultures remained negative for Klebsiella pneumoniae. Her renal function stabilized, and she recovered without any adverse effects from the medications.
Conclusion: This case highlights the growing challenge of carbapenem-resistant Klebsiella pneumoniae infections, particularly in pediatric transplant recipients. The successful use of fosfomycin emphasizes the importance of personalized treatment strategies for multidrug-resistant infections. Fosfomycin proved to be both safe and effective in treating ESBL Klebsiella infections, even in the presence of OXA-48 and NDM-1 carbapenemase genes. This case underscores the need for alternative antibiotic options and demonstrates that fosfomycin monotherapy can be a viable approach in managing such resistant infections.