A. Demitrovicova

Endocarditis due to coagulase-negative staphylococci: Data from a 22-years national survey

Dear Sir, Staphylococci are responsible for 30 to 50% of all infective endocarditis (IE) both in Europe and the US [1 3] and the trend of IE due to staphylococci is increasing. However, there is ongoing discussion on the diagnostic value of coagulase negative staphylococci in blood cultures [1 3]. In our national survey within last 22 y, 154 of 606 from all IE (24.9%) were due to staphylococci and the majority of them due to S. aureus (55%) (Table I), which was responsible for 85 IE episodes (14%) of all 604 cases. Coagulase negative staphylococci (CoNS) were responsible for 69 episodes, which represents 44.8% of staphylococcal and 11.4% of all IE. 50 cases were due to S. epidermidis, 7 S. hominis, 2 S. auricularis, 2 S. lugdunensis, 1 S. xylosus, 1 S. saprophyticus, 2 S. haemolyticus, 2 S. warneri, 1 S. simulans and 1 S. acidominimus (Table I). Only 3 S. aureus (3.5%) were methicillin resistant (MRSA) in contrast to 20 of 69 coagulase negative staphylococci (28.1%) which were methicillin resistant and 14% clindamycin resistant. However, all isolates were susceptible to tetracycline, cotrimoxazole (TMP/ SMX), vancomycin, teicoplanin and rifampin. Concerning risk factors, several of them were observed more frequently in the S. aureus IE and IE due to CoNS groups compared to all 606 cases of IE. In the population of diabetic patients (20.1% vs 11.4%, pB0.045) and patients with prosthetic valve IE (38.8% vs 14.9%, pB0.045), infective endocarditis was more frequently caused by S. aureus. Previous cardiosurgery (42.3% and 45.3% vs 9.9%, pB0.001) and pre-existing congenital or acquired heart disease (18.5% and 19.5% vs 3.3%, pB0.001) are common risk factors for both S. aureus IE and IE due to CoNS. However, mortality was higher in S. aureus IE (pB0.045) compared to all cases (25.8% vs 15%) and also in embolization due to CoNS (25.8% vs 7.1%). In contrast, mortality due to coagulase negative staphylococci was significantly lower (7.1%) compared to S. aureus and the whole group of IE, probably because of a lower proportion of rheumatic fever (1.3% vs 22.3%, pB0.01) and embolization (5.7% vs 35.5%, pB0.001) (Table II).

Predictors of mortality in bacteremic cancer patients : retrospective analysis of 64 deaths occurring among 262 bacteremic episodes

Abstract A total of 262 bacteremic episodes were observed in cancer patients in a single cancer institution during the last 7 years, and the recorded outcome was death in 65. The 65 patients who died (24.8% overall mortality) were divided retrospectively into two subgroups: (a) those who died of underlying disease with bacteremia (45 cases, 16.9% crude mortality) and (b) those who died of bacteremia (20 patients, 7.7% attributable mortality). Comparison of several risk factors in subgroups of patients who achieved a cure (197 cases) and of those who died and whose deaths were attributable (20 cases) revealed six risk factors that were associated with attributable mortality: (1) chemotherapy-induced neutropenia (P < 0.03), (2) Acinetobacter/Stenotrophomonas spp. bacteremias (P < 0.001), (3) liver failure (P < 0.001), (4) inappropriate therapy (P < 0.0001), (5) organ complications (P < 0.003) and (6) multiresistant organisms (P < 0.001). Enterococci and Pseudomonas aeruginosa, surprisingly, were found more frequently in those who died of an underlying disease with bacteremia than among patients who were cured (17.6% vs 7.6%, P < 0.05 and 29.1% vs 13.8%, P < 0.02). Those who died of infection had higher numbers of positive blood cultures, with 2.05 per episode, than did those who died of underlying disease with bacteremia (1.82) or those who were cured (1.51). Other risk factors, such as underlying disease, type of chemotherapy, origin of bacteremia, age, and catheters did not predict either overall or attributable mortality within the study group.

Infective endocarditis in elderly patients

Dear Sir, Increased age was reported a risk factor for infective endocarditis due to degenerative changes in valves and decreased immunoglobulin levels because of the involution of their immune system and previous rheumatic fever [1 3]. A nationwide 22-y survey of infective endocarditis has been performed in Slovakia in 1985 2007. We reviewed charts of patients older than 65 y in this survey: 200 (33%) elderly patients older than 65 y from a cohort of 606 patients with infective endocarditis were analysed. Among risk factors, neoplasia (21% vs 9.2%, pB0.01) and diabetes mellitus (27.1% vs 11%, pB0.01) were significantly more common among elderly patients. Previous general surgery (pB0.01) and dental surgery significantly (pB0.04), were less frequently diagnosed. Staphylococcus aureus (p B0.04) and enterococcal aetiology (pB0.05) (Table I) were more frequently observed among elderly patients. Antibiotic therapy (without surgery) was the predominant treatment strategy among elderly patients with significantly less cardiac surgery (6.6% vs 42.6%, pB0.01). However, mortality was higher (25% vs 15%, NS) than in the overall patient population. In 200 elderly patients with infective endocarditis from our nationwide survey, we observed increased mortality compared to the whole cohort of patients with infective endocarditis (606 cases). Enterococcal and staphylococcal aetiology was significantly higher in this patient population. Predominant therapeutic strategy was broad spectrum antibiotic combination therapy without cardiac surgery (probably because of age related comorbidity). Empirical antibiotic therapy for infective endocarditis in elderly patients should cover Staphylococcus aureus and enterococci. Elderly patients with neoplasia and/or diabetes mellitus are at increasing risk to developing infective endocarditis.

IMPACT OF OFLOXACIN USED PROPHYLACTICALLY IN NEUTROPENIC PATIENTS ON DEVELOPMENT OF RESISTANCE. COMMENTARY

The association between consumption of ofloxacin as prophylaxis for febrile neutropenia and incidence of gram-negative bacteremia and resistance development in Enterobacteriaceae and Pseudomonas aeruginosa was studied in a national referral cancer center. Despite increasing consumption of ofloxacin, from 0 g per year in 1990 to 2350 g per year in 1996, no increase in resistance in Enterobacteriaceae was observed. The overall incidence of resistance to quinolones was 2.8%. Only two ofloxacin-resistant Escherichia coli strains were observed within 8 years. However, the incidence of resistance by P. aeruginosa against ofloxacin during the observation period was 6.4%-21.0%. Increasing consumption of ofloxacin did not cause significant changes in resistance within the previous 8 years in gram-negative bacilli, with the exception of Acinetobacter species, in our cancer center.