Laboratory diagnoses of infections agents

DIFFERENT TYPES OF AND APPROACHES TO CLINICAL SAMPLE COLLECTION

Importance of diagnostic microbiology Laboratory diagnosis is essential for- 1. Management and treatment of individual patient 2.Effective infection control in both the hospital and community settings, as well as 3.providing invaluable epidemiological data

Who can request laboratory services? 1. All licensed physicians, dentists and optometrists. 2. All public health nurses and physicians assistants. 3. Local Health Departments. 4. Communicable Disease Specialists. Reports shall be given only to the submitter. Private individuals will not receive reports.

General requirements for collecting and submitting specimens

Identification of specimens

Specimen collection Proper specimen collection, container labeling, and culture requests are the responsibility of the ordering physician. Technologists in the Clinical Microbiology Laboratory will be familiar with specimens of choice and proper collection techniques. The technologist in the laboratory will directly handle specimens of clinical and environmental source which are received from the Postal Service or hand carried to the laboratory. The technologists will handle the clinical specimens completely by the following procedure.

Specimen handling and storage Specimen containers and requisitions will be delivered to the Clinical Microbiology Central Processing Area (CPA) within the specified period (depending on the specimen source and type) of collection. Upon receipt, the CPA staff will check requisitions for completeness. Specimens will be stored properly until they are picked-up by the microbiology staff. The CPA staff will assign numbers for the specimens and indicate them on the original requisitions.

Specimen handling and storage Upon receiving the specimen and requisition with complete data, record it in the microbiology log book in numeral order. The number assigned to the specimen is written on the specimen container and the requisition form, culture media containers, and culture media plates. In addition, date and time of processing and the name of the patient should be written clearly on all culture plates, tubes, slides or whatever used in the processing of the specimen.

Specimen rejection criteria Blood received in blood culture bottles is unsuitable for fungal isolation. Saliva is unacceptable for culture. Submit "deep cough or induced sputum." Multiple urine, stool, sputum, or routine throat specimens sent on the same day from the same source from the same patient. Bacteriology

Specimen rejection criteria Specimens in fixative (Formalin). Dried out swabs. 24 hour urine/sputum for routine bacteria, or fungi. Urine held two hours or more at room temperature. Fluids received in culture tubes. Swab material for anaerobic culture not in the proper anaerobic transport. Other specimens unsatisfactory for cultures are:

Specimen rejection criteria Gram stains for Neisseria gonorrhea on vaginal or anal crypt specimens are not diagnostic and will not be performed. Stool specimens for culture from a patient who has been an inpatient greater than 5 days will not be performed. Anaerobic cultures on vaginal, cervical, urine (unless suprapubic tap), sputum or fecal specimen. Bacteriology Other specimens unsatisfactory for cultures are:

Transport medium Allows organisms (pathogens and contaminants) to survive Non-nutritive - does not allow organisms to proliferate For bacteria – i.e., Cary Blair For viruses - virus transport media (VTM)