Antimicrobials acquired

The activity of diamidines is reduced by acid pH and in the presence of blood and serum. Microorganisms may acquire resistance by serial subculture in the presence of increasing doses of the compounds. Propamidine and dibromopropamidine, as the isethionate salts, are the major diamidine derivatives employed as antimicrobial agents propamidine in the form of eye-drops (0.1%) for amoebic infection and dibromopropamidine for topical treatment of minor infections. 

Recognizing the presumed site of infection and most common pathogens associated with the infectious source should guide antimicrobial choice, dose, and route of administration. For example, community-acquired pneumonia is caused most commonly by S. pneumoniae, E. coli is the primary cause of uncomplicated UTIs, and staphylococci and streptococci are implicated most frequently in skin and skin-structure infections (e.g., cellulitis). 

Design an appropriate empirical antimicrobial regimen based on patient-specific data for an individual with community-acquired pneumonia, aspiration pneumonia, and ventilator-... 

Niederman MS, Mandell LA, Anzueto A, et al. Guidelines for the management of adults with community-acquired pneumonia Diagnosis, assessment of severity, antimicrobial therapy, and prevention. Am J Respir Crit Care Med 2001 163 1730-1754. 

Gupta K, Sahm DF, Mayfield D, et al. Antimicrobial resistance among uropathogens that cause community-acquired urinary tract infections in women a nationwide analysis. Clin Infect Dis 2001 33 89-94. 

Aggressive, early antimicrobial therapy is critical in the management of septic patients. The regimen selected should be based on the suspected site of infection, likely pathogens, and the local antibiotic susceptibility patterns, whether the organism was acquired from the community or a hospital, and the patient s immune status. 

Sader HS, Fritsche TR, Jones RN. (2008) Antimicrobial activities of cef-taroline and ME1036 tested against clinical strains of commnnity-acquired methiciUin-resistant Staphylococcus aureus. Antimicrob Agents Chemother 52 1153-1155. 

For infections frequently encountered outside hospitals, e.g. uncomplicated urinary tract infection in young women, surveillance of resistance data of the most likely pathogens Escherichia coli) allows physicians to prescribe empiric therapy without performing cultures in the individual patient. However, in severely ill hospitalised patients, it is necessary to take samples for culture before starting empiric therapy. Microscopy of the Gram stained smear can help fine-tune empiric therapy at an early stage. Whether the infection is community-acquired or hospital-acquired, and whether the patient has been exposed to previous antimicrobial therapy should also be taken into account when choosing empiric therapy. 

The spectrum of respiratory tract infections (RTI) can vary from the common cold to acute or chronic bronchitis to community-acquired pneumonia to nosocomial pneumonia and aspiration pneumonia to ventilator-associated pneumonia to chronic pneumonia (in cystic fibrosis, histoplasmosis, tuberculosis, etc.). Important complications are lung abscess and pleural empyema that will often need drainage and prolonged antimicrobial treatment (>6 weeks). 

A controversial area of risk assessment concerns the possible effects of residues of antimicrobial drugs on the human gut flora, favoring the growth of microorganisms with natural or acquired resistance to the drug in question. Available risk assessment studies include studies in human volunteers, studies in germ-... 

Page K, Wilson M, Parkin IP (2009) Antimicrobial surfaces and their potential in reducing the role of the inanimate environment in the incidence of hospital-acquired infections. J Mater Chem 19 3819-3831... 

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