Infection with antibiotic resistant organisms is of increasing clinical importance.
In New Zealand, methicillin resistant Staph aureus (MRSA), Penicillin Insensitive Pneumococci and multi-resistant Gram negative organisms (e.g., Acinetobacter baumanii) are currently of great concern.
Multi-drug resistant Mycobacterium tuberculosis, Vancomycin resistant enterococci and Vancomycin Insensitive Staphylococci are likely to become increasing problems.
To prevent development and spread of resistant organisms - use antibiotics only when clinically indicated, avoid broad spectrum antibiotics, use as narrow spectrum as possible, keep courses short and isolate patients when such infection is likely or proven.
MRSA This should be suspected in all patients who have been previously hospitalized within two years, either in New Zealand or overseas. Community acquired MRSA infections are of increasing concern. Consider these in all patients with cellulitis which is not responding to beta-lactam antibiotics. Implement appropriate infection control measures and be guided by the Infection Control Nurses. Many patients are colonized and do not require specific therapy. For a true infection, consult an Infectious Diseases Physician regarding antibiotic therapy.
Penicillin resistant/insensitive pneumococci Consider in all serious pneumonias and especially in patients from overseas, the immunosuppressed, those with chronic lung conditions, and patients who have had repeated courses of antibiotics. If confirmed, nurse in side room, high dose beta-lactam antibiotics usually remain effective. If therapy fails or high level resistance found, consult the Infectious Diseases Service. For Pneumococcal meningitis, add IV vancomycin to IV ceftriaxone until sensitivities available. See Meningitis.
Extended spectrum beta-lactamase inhibitor (ESBL) producing Gram negative bacilli. These are being isolated increasingly commonly, including in the community as a cause of urinary tract infections and in the hospital setting, especially in patients with prior antibiotic exposure or who have recently travelled overseas. Consult Infectious Diseases regarding treatment of infections with these organisms.