Diagnosis and treatment of opportunistic infections in immunocompromised surgical patients.

The advent of successful therapy for patients who suffer many types of organ dysfunction and failure, malignancies, and acquired immunodeficiency syndrome has led to the concurrent threat of infection due to a wide array of pathogens, particularly opportunistic microbes that rarely cause disease under routine circumstances. Among patients who are subjected to extreme degrees of immunosuppression, almost any type of bacterial, fungal, viral, protozoal, or parasitic organism can exhibit pathogenic potential and lead to devastating consequences for the host. Immunosuppressive drug therapy for the purpose of organ allograft maintenance, cancer chemotherapy, or the human immunodeficiency virus exerts potent effects upon cellular immunity. Therefore, although these groups of patients are more susceptible to all types of infectious disease processes, infections due to those pathogens that require a component of cellular immunity for their eradication, such as fungi and viruses, occur at a higher frequency than that observed among normal individuals. Of critical importance, all types of infections are associated with higher rates of morbidity and mortality in immunosuppressed patients. Currently, improved diagnostic techniques and new treatment modalities have rendered many serious infections, for which suitable therapy previously did not exist, amenable to treatment. Because of the large number of immunosuppressed patients who now lead highly productive lives, it is important for the surgical practitioner to become familiar with the modalities currently available to precisely diagnose and effectively treat opportunistic infections in immunocompromised surgical patients.