C.J. is a 56-year-old white woman with a 40-year history of type 1 diabetes mellitus. Two weeks ago, she suffered a myocardial infarction (MI) for which she was hospitalized for several days. Prior to her MI, C.J. had been evaluated at an outpatient wound clinic for neuropathic ulcers on both feet. Three weeks after her MI, C.J. returns to the wound clinic for her first treatment. The physical therapist notes increased erythema around the right foot ulcer since the evaluation. The therapist contacts the primary healthcare provider to report the patient’s change in status. The wound is cultured and is positive for Staphylococcus aureus. The patient is given oral clindamycin to treat the wound infection and returns to the wound clinic the following week. The physical therapist notes that the erythema on the right foot has receded. As the therapist is taking wound measurements, C.J. mentions that she has been experiencing abdominal cramping and frequent bouts of watery diarrhea for the past several days. She has not reported this to her physician because she felt that this was a minor problem and did not want to “bother her doctor.” The physical therapist discusses with C.J. that her diarrhea may be related to the antibiotic therapy and encourages her to relay the signs and symptoms to her physician as soon as possible.
INTRODUCTION TO ANTIMICROBIAL DRUGS
Infectious diseases are among the most common forms of illness. Thus, many patients undergoing physical rehabilitation may be taking one or more antimicrobial drugs. While many of these drugs may have little direct impact on functional rehabilitation outcomes, they certainly have an impact on the overall health status of the patient.
The next four chapters address agents used to treat infections caused by bacteria, viruses, fungi, protozoa, and helminths (worms). After gaining access into the human body, these pathogens can cause illnesses ranging from minor infections to life-threatening illnesses. Antimicrobial drugs are among the most dramatic examples of advances of modern medicine. Many infectious diseases once considered incurable and lethal are now amenable to treatment, although the development of resistant organisms threatens the continued success of antimicrobial drugs. Antimicrobial drugs are classified and identified according to the primary type of infectious organism they are used to treat (eg, antibacterial, antiviral, antifungal).
The remarkably powerful and specific activity of antimicrobial drugs is due to their selective toxicity—that is, drugs are designed to selectively target structures that are either unique to microorganisms or much more important in them than in humans. Therefore, a general understanding of microbial structure and function is necessary to understand the mechanisms of action of antimicrobial agents. Notably, selective toxicity is not perfect, and antimicrobials may exert some adverse effects in humans.
Bacterial infections harm humans in several ways. Bacteria can directly damage or destroy human cells by ...