MONTREAL-The rising worldwide incidence of microbial resistance stems from a wide variety of causes and does not reflect a single global trend or etiology, Prof. Dr. Bernd Wiedemann, University of Bonn, Germany, said at a plenary session of the 19th International Congress of Chemotherapy.
Although it may be tempting to oversimplify the situation and pin the blame on an overall cause, such as the misuse, overuse, or inappropriate use of antibiotics, Dr. Wiedemann claims that local patterns of resistance arise from specific etiologies and must therefore be attacked singly.
One possible cause of increased resistance, for example, may be traced to medical advances, such as organ transplantation and cancer chemotherapy, that have paradoxically resulted in patients who are sicker and more vulnerable to infection with resistant organisms.
Although resistance to antibiotics has been reported in many areas of the world, Dr. Wiedemann said that these reports are based on highly variable standards. Comparisons are virtually meaningless in the face of different testing methods, breakpoints, surveillance techniques, and government regulations.
Establishing microbiologic standards is important, Dr. Wiedemann said, since "good epidemiology" is necessary to really understand global patterns and begin to devise preventive strategies.
He noted that specific migrations of resistant bacterial clones around the world have been documented. A resistant Streptococcus pneumoniae was traced, for instance, from South Africa to Europe and the United States, while a gentamicin(Drug information on gentamicin)-resistant Pseudomonas aeruginosa traversed the globe eastward, also arising in South Africa, but spreading to Israel, Thailand, and Singapore.
Dr. Wiedemann said that some trends bear watching because of their potential impact on worldwide public health. The rising incidence of resistant tuberculosis in drug addicts, he said, may eventually represent a serious problem in many countries, as might methicillin-resistant staphylococci, vancomycin-resistant enterococci, penicillin- and tetracycline(Drug information on tetracycline)-resistant gonococci, and multiresistant Enterobacteriaceae and Pseudomonas.