Invasive Staphylococcus aureus Infections Cohort (INSTINCT)

Abstract number: P1088

Wisplinghoff H., Kaasch A., Achilles K., Langhorst A., Peyerl-Hoffmann G., Wöhrmann A., Fätkenheuer G., Salzberger B., Kern W., Seifert H.

Introduction: Nosocomial bloodstream infections (BSIs) are important causes of morbidity and S. aureus is one of the most important nosocomial pathogens.

Methods: INSTINCT was established to prospectively monitor clinical features of S. aureus BSI (SAB) in Germany using a web-based database. Data are collected by infectious diseases physicians aided by specially trained medical personnel to monitor risk factors, predisposing conditions, portal of entry, clinical course, diagnostic and therapeutic procedures as well as outcome up to one year after SAB.

Results: Between January 2005 and September 2007, 468 cases of SAB were detected in the 3 participating university hospitals. Patients had a mean age of 61 years and 33% were female. Length of stay averaged 33 days. Underlying conditions most often included cardio-vascular (35%), or renal (27%) disorders and diabetes mellitus (27%). SAB were classified as nosocomial in 54% of patients another 26% were healthcare-associated. Primary SAB was seen in 61% of cases, of which 28% were catheter-related. Secondary SAB most often originated from skin and soft tissue infections (7%) or surgical wound infections (5%). 18% of S. aureus isolates were meticillin-resistant. Severe Sepsis and septic shock at onset of SAB were seen in 4.5% and 2.5% of patients, respectively, secondary complications were reported in 14% of patients, most commonly endocarditis, osteomyelitis or spondylodiscitis. The mean duration of S. aureus bacteraemia was 3.5 days. Patients received a mean of 16±13 days of appropriate anti-staphylococcal therapy. Adherence to ID consult recommendations such as TEE (recommended in 50%, followed in 34%) and follow-up blood-cultures (61%; 48%) varied significantly between centres. The crude 7-day-mortality was 15%, in-hospital mortality was 23%.

Conclusion: INSTINCT currently represents one of the most detailed prospective SAB studies. Data from the first years underscore the importance of SAB and confirm the feasibility of this very detailed monitoring design.