Nosocomial pneumonia cause

Nosocomial pneumonia For the treatment of nosocomial pneumonia caused by S. aureus (methicillin-susceptible and -resistant strains), orS. pneumoniae (penicillin-susceptible strains only). 

Linezolid is FDA approved for treatment of infections caused by vancomycin-resistant E. faecium nosocomial pneumonia caused by methicillin-susceptible and methicillin-resistant strains of S. aureus community-acquired pneumonia caused by penicillin-susceptible strains of S. pneumoniae complicated skin and skin-structure infections caused by streptococci and methicillin-susceptible and -resistant strains of S. aureus and uncomplicated skin and skin-structure infections. In noncomparative studies, linezolid (600 mg twice daily) has had clinical and miaobiological cure rates in the range of 85 to 90% in treatment of a variety of infections (soft tissue, urinary tract, and bacteremia) caused by vancomycin-resistant E. faecium. A 200-mg, twice-daily dose was less effective, with clinical and microbiological cure rates of approximately 75 and 59%, respectively. The 600-mg, twice-daily dose, therefore, should be used for treatment of infections caused by enterococci. A 400-mg, twice-daily dosage regimen is recommended only for treatment of uncomplicated skin and skin-structure infections. 

Cure rates with linezolid ( 60%) were similar to those with vancomycin for nosocomial pneumonia caused by methicillin-resistant or -susceptible S. aureus. Linezolid efficacy also was similar to that of either oxacillin or vancomycin for skin arul skin-structure infections, the majority of cases due to by 8. aureus. Linezolid appears comparable in efficacy to varwomycin for methicillin-resistant strains. Linezolid may be effective for patients with methicillin-resistant S. aureus infections who are failing varwomycin therapy or whose isolates have reduced susceptibility to vancomycin. Linezolid is bacteriostatic for staphylococci arul enterococci arul probably should not be used to treat suspected erulocarditis. 

Table 1 Host-Associated Risk Factors and Preventive Measures for Nosocomial Pneumonia Caused by Bacteria... 

In severe nosocomial pneumonia caused by Acinetobacter resistant to the carbopenem and the aminoglycosides, some clinical studies suggest that sulbactam is effective (73), but emergence of resistance may limit its usefulness the organism has retained its susceptibility to polymyxin B. 

Nosocomial pneumonia caused by Stenotrophomonas (Xanthomonas) mal-tophilia parallels the use of antibiotic pressure in patients with underlying debilitating chronic diseases, advanced age, and the use of invasive monitoring devices, and is typically associated with imipenem usage (72). Carmeli and Samore (74) report that the emergence of this organism can be traced to the use of either imipenem or ceftazidime. 

Viruses, also, can be an important and often unappreciated cause of nosocomial pneumonia, causing as many as 20% of endemic nosocomial pneumonia infections (1). Nosocomial respiratory viral infections have exogenous sources and usually follow community outbreaks occurring during particular times of the year (8-15). A number of viruses—adenoviruses, influenza virus. 

Doripenem Carbepenem 2007 2008 Launched Nosocomial infections caused by S. aureus, P. aeruginosa, S. pneumoniae... 

Ceftobiprole Cephalosporin 2008 2009 2010 Nosocomial pneumonia and cSSSIs caused by MRSA... 

Levofloxacin (1), the levo-isomer or the (5)-enantiomer of ofloxacin, received FDA approval in 1996 (Fish, 2003 Hurst et al., 2002 Mascaretti, 2003 Norrby, 1999 North et al., 1998). The initial approval covered community-acquired pneumonia, acute bacterial exacerbation of chronic bronchitis, acute maxillary sinusitis, uncomplicated skin and skin structure infections, acute pyelonephritis, and complicated urinary tract infections (North et al., 1998). Four years later, the levofloxacin indication list grew to include community-acquired pneumonia caused by penicillin-resistant Streptococcus pneumoniae. In addition, in 2002, nosocomial (hospital-acquired) pneumonia caused by methicillin-susceptible Staphylococcus aureus, Pseudomonas aeruginosa, Serratia marcescens, Haemophilus influenzae, Kliebsella pneumoniae, and Escherichia coli was added (Hurst et al., 2002). Finally in 2004, LVX was approved as a post-exposure treatment for individuals exposed to Bacillus anthracis, the microbe that causes anthrax, via inhalation (FDA, 2004). 

Jarvis, V.R., Munn, V.P., Highsmith, A.K., Culver, D.H., Hughes, J.M. The epidemiology of nosocomial infection caused by Klebsiella pneumoniae. Infect Control 6 (1985) 68-74. 

Ciprofloxacin is a fluoroquinolone antibiotic that interferes with microbial DNA synthesis. It is indicated in the treatment of infections of the lower respiratory tract, skin and skin structure, bones and joints, urinary tract gonorrhea, chancroid, and infectious diarrhea caused by susceptible strains of specific organisms typhoid fever uncomplicated cervical and urethral gonorrhea women with acute uncomplicated cystitis acute sinusitis nosocomial pneumonia chronic bacterial prostatitis complicated intra-abdominal infections reduction of incidence or progression of inhalational anthrax following exposure to aerosolized Bacillus anthracis. Cipro IV Used for empirical therapy for febrile neutropenic patients. 

Levofloxacin is a fluoroquinolone/ophthalmic/antibiotic that interferes with microbial DNA synthesis. It is indicated in the treatment of acute maxillary sinusitis, acute bacterial exacerbation of chronic bronchitis, nosocomial pneumonia, community-acquired pneumonia, skin and skin structure infections, chronic bacterial prostatitis, urinary tract infection (UTI), inhalational anthrax (postexposure), and acute pyelonephritis caused by susceptible strains of specific microorganisms. Ophthalmic use is for the treatment of conjunctivitis caused by susceptible strains of aerobic Gram-positive and aerobic Gram-negative microorganisms. 

THERAPEUTIC USES Qumupristrn/dalfopristin is approved in the U.S. for treatment of infections caused by vancomycin-resistant strains of E. faecium and comphcated skin and skin-structure infections caused by methicilUn-susceptible strains of S. aureus or S. pyogenes. In Europe, it also is approved for treatment of nosocomial pneumonia and infections caused by methiciUin-resistant strains of S. aureus. Cure rates for a variety of infections caused by vancomycin-resistant E. faecium were -70% with quinupiistin/dalfopiistin at a dose of 7.5 mg/kg every 8-12 hours. Quinupiistin/dal-fopiistin should be reserved for treatment of serious infections caused by multiple-drug-resistant gram-positive organisms such as vancomycin-resistant E. faecium. 

Mcmullin, B.B., Chittock, D.R., Roscoe, D.L., Garcha, H., Wang, L., Miller, C.C., 2005. The antimicrobial effect of nitric oxide on the bacteria that cause nosocomial pneumonia in mechanically ventilated patients in the intensive care unit Respiratory Care 50,1451-1456. 

Table 3 Etiologic Pathogens Likely to Cause Nosocomial Pneumonia...

Nosocomial pneumonia is the second most common nosocomial infection (1) and the most common nosocomial infection in intensive care units (ICUs). It affects more than 250,000 acute care patients annually in the United States (2). The Centers for Disease Control and Prevention (CDC) recently estimated that nosocomial pneumonia is a primary or contributing cause for more than 30,000 deaths annually in the United States (3). To decrease the incidence of nosocomial pneumonia, hospitals must focus their considerable prevention efforts. However, these efforts begin by appropriate monitoring of this costly complication of hospital care. This task is even more involved because nosocomial pneumonia is probably more than one syndrome with multiple pathogeneses. 

Besides the role of pathogens, worsening of respiratory failure caused by nosocomial pneumonia, presence of shock, and an inappropriate antibiotic treatment were associated with higher fatality rate (22). The attributable mortality rate of nosocomial pneumonia is still not known from most of these studies, because of the well-known relationship between severity of illness and pneumonia. In addition, it is difficult to establish whether such critically ill patients would have survived if nosocomial pneumonia had not occurred (9,23). However, more recent studies have further clarified the influence of nosocomial pneumonia on death. Fagon et al. reported that the mortality rate attributable to nosocomial pneumonia exceeded 25%, corresponding to a relative risk of death equal to 2.0, (respectively 40% and 2.5 in cases of pneumonia caused by Pseudomonas or Acinetobacter species) (24). Bueno-Cavanillas supported these results by reporting that the risk of mortality was almost three times higher in patients with pneumonia than in noninfected patients (relative risk 2.95 Cl 95, 1.73-5.03) (25). 

Vancomycin intermediate 5. aureus, first isolated in Japan in May 1996, then subsequently in the eastern United States (2,3), may be an example of transfer of exogenous genetic material. Transfer of vancomycin resistance from vancomycin-resistant enterococci (VRE) to S. aureus has been demonstrated in the laboratory (4,5). Because S. aureus is a leading cause of nosocomial pneumonia, 37.5% of which have become methicillin resistant (6), the threat of an increasing prevalence of VISA and the eventual appearance of vancomycin-resistant 5. aureus (VRSA) have sobering implications. Detection of VISA will ensure proper isolation to prevent nosocomial spread and initiate appropriate, albeit less than optimal, therapy. 

Similar to cases with P. aeruginosa, nosocomial ventilator-associated pneumonia caused by Acinetobacter is associated with a high mortality rate. In a study of 48 patients (70), pneumonia caused by these two organisms have a mortality rate of 71.4% compared to other pathogens (40.7%), with the observation that this rate was in excess of that observed for the underlying disease however, the impact of antimicrobial therapy was not discussed. 

---