Office microscopy in the diagnosis of infectious diseases.

Microscopy of clinical specimens is a rapid and inexpensive method for the presumptive diagnosis of certain infectious diseases. Early diagnosis permits the physician to initiate appropriate therapy without waiting for culture results. Examination of the Gramstained smear gives information on the inflammatory response, as well as the bacteria involved. Accurate interpretation of the smear, however, requires some training and experience. This article describes the microscopic methods commonly used in the laboratory and their application to office practice.