Intravenous (IV) cefazolin with oral probenecid: A novel daily regimen for the management of Methicillin Sensitive Staphylococcus aureus (MSSA) bacteremia in a patient with renal dysfunction.

A 78 year old man developed a methicillin sensitive (MSSA) post-operative wound infection following an elective L2-L4 laminectomy. He was treated with surgical debridement which was to be followed by a planned 6 weeks course of cefazolin. However, two weeks post debridement, a follow-up MRI revealed an L3-L5 epidural abscess, septic arthritis and vertebral osteomyelitis prompting repeat surgical debridement. No purulence was noted, and operative cultures were negative for growth. His hospital course was complicated by acute kidney injury and a renal biopsy reveled crescentic glomerulonephritis consistent with post infectious glomerulonephritis. He was treated with daptomycin, followed by oral linezolid. Five months after his original laminectomy, he developed purulent drainage from his back wound. Blood cultures grew MSSA and a repeat aspirate done by interventional radiology also grew MSSA. He improved with nafcillin and was transitioned to telavancin on discharge to facilitate once daily treatment. While on telavancin he developed increasing back pain and fever. Therefore, the regimen was changed to IV cefazolin and oral probenecid for five weeks followed by oral cephalexin to complete a total of 12 weeks of therapy. There is no evidence of disease recurrence one year after completion of therapy. IV cefazolin with oral probenecid may represent a once daily IV treatment option for patients with MSSA bacteremia and kidney disease.