Prediction of poorer prognosis by infection with antibiotic-resistant gram-positive cocci than by infection with antibiotic-sensitive strains

Hypotheses: Surgical patients with antibiotic-resistant gram-positive cocca l (GPC) infections have a poorer prognosis than those with antibiotic-sensi tive GPC infections, and colonization with resistant GPC predisposes to the development of resistant GPC infections. Design: All infections among surgical patients from December 1, 1996, to De cember 1, 1998, were followed up prospectively. Patients with antibiotic-se nsitive and antibiotic-resistant GPC infections were compared. Cohorts were also subdivided on the basis of GPC species, colonization status, and immu nosuppression. Setting: The surgical wards and intensive care units of a tertiary care, un iversity hospital. Main Outcome Measures: In-hospital mortality. in-hospital mortality during antibiotic therapy, length of stay, and length of stay from the time of ini tiation of antibiotics to discharge. Result: Antibiotic-resistant GPC infection compared with antibiotic-sensiti ve GPC infection was associated with a higher mortality and previous coloni zation rate (25.8% and 31.0% vs 17.6% and 8.8%, respectively; P = .04 and P <.001, respectively) and a markedly longer length of stay (55.0 +/- 3.3 vs 31.0 +/- 2.0 days, P<.001). Length of stay and treatment to discharge times were longer after resistant Staphylococcus aureus infections than after re sistant Staphylococcus epidermidis infections. The mortality and length of stay of patients with gentamicin-resistant or vancomycin-resistant enteroco ccal infections were equivalently higher than those with antibiotic-sensiti ve enterococcal infections. Transplant recipients with resistant enterococc al infection had the highest mortality (41.9%). Conclusions: Surgical patients who develop antibiotic-resistant GPC infecti ons have a significantly higher mortality rate, longer length of stay, and longer treatment to discharge time than patients with antibiotic-sensitive GPC infections. Colonization with resistant GPC predisposes to resistant GP C infection. Gentamicin-resistant enterococcus appears to be as virulent as vancomycin-resistant enterococcus.