Daptomycin is a novel antibiotic with a proven efficacy against Gram-positive-bacteria, including MRSA. Data from the European-Cubicin-Outcomes-Registry-and-Experience show its excellent safety profile. Nephrotoxicity is rarely registered, occurring mostly in patients with renal failure at baseline. We report about a patient with normal renal function treated with daptomycin who developed acute renal failure (ARF).
A 57-year-old man with a 5-year history of post-traumatic right lower limb chronic osteomyelitis due to MRSA infection, was admitted to our Unit for a non-oliguric ARF appeared two weeks before. Two months before he has been treated with i.v. daptomycin at 350 mg once-a-day (4.6 mg/kg) for six weeks. At admission, physical examination and blood pressure were normal. Laboratory data showed a serum creatinine of 2.7 mg/dl, haemoglobin 7.8 g/dl, CRP 1.52 mg/dl, serum leucocytes count 7.660 mL. Proteinuria was 952 mg/day; urinary sediment was active with numerous red and white cells. There were high levels of urinary NGAL and lisozyme. At ultrasound, kidneys appeared normal so that renal biopsy was performed. At light microscopy 2/9 glomeruli showed global sclerosis, the remnants presented diffuse mild mesangial matrix expansion and diffuse capillary membrane thickness. Focal thickness of Bowman’s capsula and pseudo-crescents were present. There was also a remarkable tubulo-interstitial damage with severe oedema, diffuse leucocytes infiltration and tubulitis. Vessels were normal. On immunofluorescence, C3 granular deposition with a “starry sky” pattern and mild focal IgA deposits were seen along the capillary walls. The patient was transfused and re-hydrated and after one week discharged with a serum creatinine of 1.4 mg/dl.
Our patient presented an acute renal failure after daptomycin administration. Histological findings have shown a kidney damage secondary to chronic post-infectious glomerulonephritis, presumably MRSA-related; and an acute TIN which could be due to daptomicin therapy. Our case suggests daptomycin as a potential nephrotoxic drug.