Documented fungal infections after prophylaxis or therapy with wide spectrum antibiotics: relationship between certain fungal pathogens and particular antimicrobials?

Antibiotics are known to be one of the major risk factors for fungal infection. We investigated whether there was a relationship between particular documented fungal infections and therapeutically or prophylactically administered antimicrobials in 105 patients with fungemia or histologically proven invasive aspergillosis or fusariosis. Out of 105 patients, 82.9% received antimicrobials affecting anaerobic microbial gut flora such as: imipenem, vancomycin, ceftazidime, metronidazole, clindamycin or ampicillin-sulbactam. In addition, 44.5% of patients had received prophylaxis with ofloxacin. 31.5% of Candida albicans fungemias occurred despite empiric therapy with amphotericin B and 21.1% during prophylaxis with azoles. The incidence of C. albicans infections (fungemias) was significantly higher (58.9% vs 33.7%, p<0.04) in patients receiving antibiotics not affecting anaerobic gut flora such as ofloxacin, an aminoglycoside or azithromycin. On the other hand, patients treated with third generation cephalosporins, carbapenems, glycopeptides, and broad spectrum penicillins were more likely to develop proven invasive Aspergillus spp. infection (27.9% vs 5.3%, p<0.001) in comparison to those treated with antimicrobials which preserve anaerobic gut flora.

Native valve staphylococcal endocarditis: etiology, risk factors and outcome in 53 cases.

Fifty-three cases of staphylococcal endocarditis from a national endocarditis survey were analyzed for risk factors and outcome. Thirty of 53 patients had predisposing heart disease (39.6% rheumatic fever) but only 3 were on dialysis, only 2 had central venous catheter, only 2 intravenous drug abuse but 7 had prior cardiosurgery. Mortality was 39.6%. In analyzing risk factors for death, attributable mortality was significantly associated with skin infections (P < 0.05), embolization (P < 0.02), inappropriate therapy (P < 0.005) either because of too short therapy (P < 0.003) or wrong antibiotic combination (P < 0.01). Surgical therapy was associated with better outcome (4.8% deaths vs. 31.2% survivors, P < 0.04).