Resistant organisms

Mixtures of sulfas (eg, the tri-sulfapyrimidines) have also been used for this purpose. Resistant organisms frequently result after a urinary tract infection has been treated with sulfonamides, however. 

Antibacterial Agents. There is a continuous need for new antibiotics primarily as a result of bacterial resistance. There are two aspects to this phenomenon. Fkst, as the mote common pathogens are contioUed by antibiotics, less common, highly resistant organisms present mote prominent health... 

A number of oxime derivatives of rifaldehyde have been prepared. Many of these derivatives exhibit good activity against rifampicin-resistant organisms (151,152). 

Table 3. Activity of Chloramphenicol and Analogues Against Chloramphenicol-Sensitive and -Resistant Organisms...

Boiling - This involves bringing the water to its boiling point in a container over heat. The water must be maintained at this temperature 15 to 20 minutes. This will disinfect the water. Boiling water is an effective method of treatment because no important waterborne diseases are caused by heat-resisting organisms. 

Polychloroprene CR Satisfactory resistance organics fair poor with oxidative chemicals and hydrocarbon solvents Fair 0 to 100... 

Tuberculosis caused by drug-resistant organisms should be considered in patients who have no response to therapy and in patients who have been treated in the past... 

The emergence of resistant organisms m be prevented. A classical example here occurs in combined antitubercular therapy (see earlier). 

The origins of the glycopeptide-resistance genes are unknown and share little homology with genes found in intrinsically glycopeptide-resistant organisms. 

In order to lessen the risk of eye-drops becoming heavily contaminated either by repeated inoculation or growth of resistant organisms in the solntion, use is restricted, after the container is first opened, to 1 month. This is nsnally reduced to 7 days for hospital ward use on one eye of a single patient. The period is shorter in the hospital environment because of the greater danger of contamination by potential pathogens, particnlarly pseudomonads. 

Inadequate diagnosis resulting in poor initial antimicrobial selection, poor source control, or the development of a new infection with a resistant organism is a relatively common cause of antimicrobial failure. 

Patients with a history of recent antimicrobial use may have altered normal flora or harbor resistant organisms. If a patient develops a new infection while on therapy, fails therapy, or has received antimicrobials recently, it is prudent to prescribe a different class of antimicrobial because resistance is likely. Previous hospitalization or health care utilization (e.g., residing in a nursing home, hemodialysis, and outpatient antimicrobial therapy) are risk factors for the acquisition of nosocomial pathogens, which are often resistant organisms. 

Compliance is essential to ensure efficacy of a particular agent. Patients may stop taking their antibiotics once the symptoms subside and save them for a future infection. If the patient does not complete the course of therapy, the infection may not be eradicated, and resistance may emerge. Self-medication of saved antibiotics may be inappropriate and harmful and may select for resistant organisms. Poor patient adherence maybe due to adverse effects, tolerability, cost, and lack of patient education. 

Risk factors for developing an infection caused by a resistant pathogen generally are related to the prior use of antibiotics, insertion of catheters or other invasive devices, and hospitalization in a unit contaminated/colonized with resistant organisms. The following is a more complete list of factors influencing infection from a resistant organism ... 

Treatment guidelines developed by the Sinus and Allergy Health Partnership reflect antibiotic choices that are likely to result in favorable clinical and bacteriologic outcomes based on pathogen distribution, spontaneous resolution rates, and nationwide resistance patterns.310 These guidelines (Figs. 69-3 and 69-4) stratify therapy based on severity of disease and risk of infection with resistant organisms, defined as mild disease in patients with prior antibiotic use within 4 to 6 weeks. Other risk factors for resistance include day-care attendance or frequent... 

If immunocompromised patients experience frequent or severe recurrences, particularly of esophageal candidiasis, chronic maintenance therapy with fluconazole 100 to 200 mg daily should be considered. In patients with infrequent or mild cases, secondary prophylaxis is not recommended. The rationale for not giving prophylaxis includes availability of effective treatments for acute episodes, risk of developing resistant organisms, potential for drug interactions, and the cost of therapy. 

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