Clinical efficacy, tolerability, and cost savings associated with the use of open-label metronidazole plus ceftriaxone once daily compared with ticarcillin/clavulanate every 6 hours as empiric treatment for diabetic lower-extremity infections in older males

Abstract

Background: Patients with diabetes mellitus, particularly those with poor glucose control, commonly experience various medical complications related to the disease (eg, renal impairment, decreased peripheral vascular circulation, suppressed immune function). Infections of the lower extremities can range from superficial cellulitis to ulcerative, deep soft-tissue infections to osteomyelitis that necessitates some degree of amputation. Objective: This study compared the efficacy, tolerability, and cost differences associated with the use of metronidazole plus ceftriaxone (MTZ/CTX) given once daily with those of ticarcillin/clavulanate potassium (T/C) given every 6 hours in hospitalized older males with diabetic lower-extremity infections. Methods: This prospective, open-label study was conducted at a Veterans Affairs Medical Center. Male patients with diabetes and a lower-extremity infection were randomized to receive MTZ/CTX 1 g once daily or T/C 3.1 g every 6 hours. Treatment success was determined at 96 hours or on discontinuation of antibiotic. Success was measured in terms of body temperature <38.3°C (100.6°F), normalization of the finger-stick blood sugar concentration, improvement in wound staging, or a white blood cell count <10,000 cells/mm 3. Medication acquisition costs per treatment arm were calculated and compared. Results: Seventy patients were enrolled in the study (36 MTZ/CTX, 34 T/C). The study population had a mean (SD) age of 63.8 (10.8) years, a duration of diabetes of 12.4 (9.1) years, 0.5 (0.7) diabetes-related comorbidities, and an initial creatinine clearance of 67.1 (26.0) mL/min. There were no significant differences between groups at randomization. At 96 hours, treatment success was achieved in 31 (86%) patients in the MTZ/CTX group, compared with 28 (82%) patients in the T/C group ( P = NS). Twenty-six patients were considered successfully treated on the final day of therapy in both the MTZ/CTX group (72%) and the T/C group (76%) ( P = NS). There were no significant differences in primary or secondary measures of success between the 2 groups. No single or multiple baseline factors predicted treatment success or failure. No patient experienced adverse events considered related to study medication. MTZ/CTX was associated with savings of $61.06 per hospital admission, or $2198.05 for all patients who received this combination. Conclusion: In this population of older males, once-daily MTZ/CTX was as well tolerated and effective as T/C in the treatment of diabetic lower-extremity infections and was associated with reduced institutional costs.