Clinical and Research Training in Infectious Diseases: Clinical Microbiology Service

Acting Service Chief
Esther Babady, PhD, D(ABMM)

The Microbiology Service in the Department of Laboratory Medicine works in close collaboration with the Infectious Diseases Service. It is staffed by a service chief, a director of molecular microbiology, a manager, supervisors, technologists, technicians, and clerical personnel. The Microbiology Service, with its laboratories of bacteriology, mycobacteriology, mycology, parasitology, virology, serology, molecular biology, and molecular epidemiology, is open 24 hours a day. It is located one floor below the Infectious Diseases Service.

The microbiology laboratory plays a fundamental role in the diagnosis of infection at Memorial Sloan Kettering. The primary goal of the Clinical Microbiology Service is to determine the presence and nature of microorganisms in material from patients. Diagnosis and management of infections can be especially difficult in patients who are immunocompromised due to drug therapy or underlying disease. The usual hallmarks of infection in patients with intact immune systems, such as leukocytosis and antibody response, may be absent. Also, infections in the immunosuppressed patient may be caused by unusual organisms whose identification requires special techniques performed by the Clinical Microbiology Service. The information obtained in the microbiology lab, when correlated with clinical impressions and other laboratory test results, helps in diagnosing infection and frequently guides in the selection of specific therapy.

Classic methods used to demonstrate microorganisms in a specimen submitted to the laboratory are visualization techniques with stains and wet preparations, as well as culture and non-cultural methods involving immunologic and immunochemical techniques. However, the emergence of new infections and the re-emergence of older ones, together with generalized trends toward increased resistance of bacteria to antibiotics, have led to circumstances in which the use of classic microbiologic techniques may not be adequate for the proper diagnosis of infecting microorganisms.

The introduction of more-advanced techniques has enhanced the capabilities of the service, which now includes a molecular epidemiology section that types organisms of nosocomial interest, a virology laboratory that employs both direct fluorescent microscopy and shell-vial assays for rapid virus detection, and a molecular microbiology laboratory that uses various amplification technologies for rapid organism detection. All of these services work best when laboratory personnel have close working relationships within the hospital with clinicians, epidemiologists, and other medical staff, and outside the hospital with centralized health agencies, reference laboratories, and research organizations.