Role of the microbiology laboratory in care of the immunosuppressed patient.
In the immunosuppressed patient the usual hallmarks of infection, such as leukocytosis and antibody response, may be absent; thus the microbiology laboratory plays a fundamental role in the diagnosis of infection. Methods used to demonstrate microorganisms in a specimen submitted to the laboratory include visualization techniques, culture, and non-cultural methods involving immunologic, immunochemical, and nucleic acid probe methodologies. Because infections in the immunosuppressed patient may be caused by unusual organisms whose identification requires special techniques, close communication between the physician and the laboratory is important. New technologies allow the clinical microbiology laboratory to gather important diagnostic information more readily. When these results are delivered rapidly to physicians via computerized information systems, care of the immunosuppressed patient is significantly enhanced.