Therapeutic drug monitoring-guided high dose meropenem therapy of a multidrug resistant Acinetobacter baumannii - A case report

BACKGROUND: Infections with multidrug resistant Acinetobacter baumannii in immunocompromised patients are life-threatening. Therapeutic options are rare in this context, but patients are dependent on an effective antibiotic therapy. Thus, new antibiotic strategies are deemed necessary. CASE PRESENTATION: This case report recounts the therapeutic drug monitoring-guided meropenem therapy of a 32 years old patient admitted with acute exacerbation of cystic fibrosis. Veno-venous extracorporeal membrane oxygenation was initiated on the first day of admission to the intensive care unit. The patient showed insufficient serum trough levels of meropenem despite the maximum approved dose (2g every 8h) was administered which was due to augmented renal clearance. Through continuous infusion of the same cumulative dose, target levels were reached. On day 17 of admission, the patient underwent successful double-lung-transplant surgery and extracorporeal membrane oxygenation was ended. Unfortunately, the donor's lung was colonized with a multidrug resistant Acinetobacter baumannii that was positive for OXA-23 carbapenemase. Hence a combination therapy of intravenous sulbactam, tigecycline, meropenem and inhalative colistin was established, with a known minimal inhibitory concentration for meropenem of 32 mg/l. Under continuous infusion of 8 g meropenem/day, serum levels exceeded 32 mg/l over 12 days. The patient was transferred from the intensive care unit to a general ward without any signs of infection. CONCLUSIONS: Therapeutic drug monitoring-guided meropenem may be a sound new therapeutic option in eradicating multidrug resistant Acinetobacter and offer a novel therapeutic option in the field of personalized medicine.