Section 3 : Specimen Collection and Processing

Drawing of an Entero-Test capsule. In comparison with intubation, this capsule allows a less invasive examination of duodenum contents for parasitic infection.

Diagram of the stomach, showing the antral region.

Plastic collection device for obtaining specimen for pinworm analysis.

Alternative method for pinworm collection when a paddle device is unavailable. Adapted from reference (39).

Disposable sanitary device for collection of stool specimens. Oral and written directions for specimen timing, preservation, and transport to the laboratory should be provided to the patient.

For parasitology studies, patients must be given one or two special transport vials and directions for their use.

Illustrated instructions on how to use the parasitology transport and preservative vial(s) may be helpful to patients. A non-mercury-containing fixative may be used in place of polyvinyl alcohol (PVA). Adapted from reference (39).

Specimen quality is judged microscopically. The presence of epithelial cells usually signals the presence of commensal flora that can confuse accurate interpretation.

A Lukens trap is used for collecting many respiratory aspirates.

Nasopharyngeal specimens are often collected inadequately. To reach the nasopharynx, the swab should be inserted approximately half the distance from the base of the nose to the ear.

Diagram of the nose and nasopharyngeal region. While nasal and nasopharyngeal specimens may be obtained by swab, a needle aspirate is the specimen of choice for determining the etiologic agent(s) of sinusitis.

Sterile, prepackaged sputum collection containers are provided to patients along with oral and written instructions on how to collect an appropriate specimen. In this system, sputum is collected in the funnel-shaped device. The tube that contains the specimen is removed, and the cap is firmly applied.

Proper technique for obtaining throat specimens. Firmly sampling only the inflamed areas of the throat and tonsils and avoiding other oral sites will enhance detection of etiologic agents.

Sterile, prepackaged urine collection cups are made available to patients, along with oral and written instructions (A). Urine can then be transffered to a special transport tube with preservatives (B); this step is usually performed by the health care personnel.

Sterile, prepackaged urine collection cups are made available to patients, along with oral and written instructions (A). Urine can then be transffered to a special transport tube with preservatives (B); this step is usually performed by the health care personnel.

Wound specimens should, at the least, be labeled as “surface wound” or “deep wound.” The laboratory depends on this information for selecting appropriate culture media and interpreting results.

Diagram of the ear. A swab is not the specimen of choice for laboratory diagnosis of otitis media because it obviously will not reach the infected area. Preparing the ear for specimen collection is a critical step in obtaining an appropriate specimen.

Diagram of the eye. The nature and potential severity of infections of the eye dictate special attention to the details of specimen management and an accurate description of the specimen submitted for analysis.