A prospective study was conducted to determine the incidence, risk factors and pathogens of ventilator-associated pneumonia (VAP) in 198 patients requiring mechanical ventilation for more than 48 hours. VAP occurred in 67 (33.8%) patients. Risk factors associated with VAP were admission APACHE II score >20 (odds ratio [OR] 4.77, 95% confidence interval [CI] 2.04-11.27, P<0.001), mechanical ventilation > 10 days (OR 44.4, 95% CI 2.16-26.7, P< 0.0001), ICU length of stay >10 days (OR 9.4, 95% CI 3.55-25.65, P< 0.0001), and admission PaO2/FiO2 ratio <200mmHg (OR 3.4, 95% CI 1.00-11.41, P<0.05). Logistic regression analysis showed a relationship between VAP and length of stay in ICU, duration of fever and presence of catheter-related infection. The pathogens isolated were predominantly gram-negative bacteria (83.2%), with a high proportion of Acinetobacter spp. (35%) resistant to commonly used antimicrobial agents. The mortality rate was not influenced by VAP.

The in-vitro susceptibilities of 198 isolates of Pseudomonas aeruginosa from clinical human specimens were determined by an agar dilution technique against beta-lactams and aminoglycosides. These isolates were susceptible to imipenem, aztreonam and ceftazidime with the minimum inhibitory concentration (MIC) for 90% of the strains tested being 8, 16 and 8 micrograms/ml, respectively. Aminoglycosides, except amikacin, had low activity (MIC90 greater than 128 micrograms/ml).

The first known case of pancreatic abscess caused by Clostridium difficile in a patient with no history of diarrhea or previous antibiotic therapy is presented. After surgical intervention and antibiotic therapy with metronidazole (500 mg every 8 h) and cefotaxime (1 g every 8 h) the patient recovered completely.