The proceedings in this issue of Annals are based on selected lectures given at the symposium ''Infectious Diseases: A Focus on Current Concepts and Emerging Therapies in Emergency Care,'' which was sponsored by the Department of Emergency Medicine of the Wayne State University School of Medicine. The conference took place on September 21 and 22, 1993, and the invited speakers were recognized experts in the field. The rapidly evolving world of infectious diseases has changed the practice of medicine. The battle against microbes has not been won. The emergence of new pathogens, the rapid development of antibiotic resistance in known pathogens, and the return of old foes provide new challenges for emergency physicians. No longer can we assume that ''standard therapy'' will always be effective. We must be aware of local, regional, and global epidemiologic patterns to provide quality patient care. The papers in this issue review some of these important issues in infectious diseases. The first three papers deal with antimicrobial resistance and sepsis. The first paper provides a brief introduction to the problem of antimicrobial resistance and is followed by a review of resistant Gram-positive bacteria. The next important paper, ''Molecular Methods: Applications for Clinical Infectious Diseases,'' provides a basis for understanding the molecular biology of infectious diseases. Although this material may be less familiar to the older practicing physician, recent graduates will be conversant with much of the information. The concepts discussed are used in much of the current research and emerging practice in clinical medicine. In the near future, rapid diagnostic tests, derived from the molecular biology laboratory, will revolutionize the practice of medicine. This paper is followed by a summary of the virology and mechanisms of disease of HIV, together with a guide to the evaluation and treatment of HIV-associated illness in the emergency department. The final papers discuss rapid diagnosis and resistance testing of Mycobacterium tuberculosis. The return of this notorious pathogen is a major issue of urban EDs. Traditional diagnostic measures often take weeks or months, and this has removed the diagnostic and therapeutic decisions from the ED. The possibility of obtaining a definitive diagnosis in a matter of hours, again based on the methods of molecular biology, will both enhance patient care and provide for better epidemiologic control of this killer disease.
