Microbiology Specimens: Mycology

Abscess / Pus / Aspirate

The aspirated material should be placed in a sterile container. If a very small amount of material is collected, it may be washed from the syringe into 1 mL sterile water or saline to a sterile container. Do not send needles.

Note: Please examine specimen collection and transportation supplies to be sure they do not include expired containers.

If a swab is used, it should be extended into the depths of the wound without touching the adjacent skin margins. It may be placed in bacterial transport medium or in a sterile container with 1 mL sterile water or saline.

Blood

1. Submit 5 to 10 mL blood in heparin or Isolator™.

2. Prepare the skin for venipuncture as follows.

a. First cleanse the venipuncture site with isopropanol. Then use tincture of iodine to disinfect the site using progressively larger concentric circles. Iodine should remain in contact with skin for about one minute to ensure disinfection.

b. The venipuncture site must not be palpated after preparation. Blood is then drawn. Following venipuncture, alcohol is used to remove the iodine from the site.

3. Room temperature storage is sufficient if there is to be any delay in transport.

Bone Marrow

1. Submit approximately 0.3 mL bone marrow in a heparinized tube. Do not send a syringe with a needle attached to it.

2. Room temperature storage is recommended if there is to be any delay in transport.

Bronchial Brush

1. Insert the brush into 2 mL sterile saline or water in a sterile screw-cap container.

2. Room temperature storage is recommended if there is to be any delay in transport.

Cerebrospinal Fluid (CSF)

1. The specimen is collected by the physician. At least 3 mL is recommended. At least 5 mL is recommended as optimal for test of cure for cryptococcal infections.

2. Incubate the specimen at 37°C if possible if there is to be any delay in transport. If an incubator is not available, maintain the specimen at room temperature.

Cutaneous Specimens

1. Skin scrapings are taken from an area previously cleansed with 70% alcohol on gauze sponges (use sterile water or broth if alcohol is not available). Scrape the entire periphery of the lesion(s) with a sterile scalpel or the edge of a glass slide. Place scrapings in a sterile screw-cap container or between clean glass slides in a slide holder, or inoculate fungal medium (not necessarily supplied by LabCorp). Note: Lesions should be untreated with topical antifungal agents for at least one week before culturing.

2. A skin biopsy specimen or punch biopsy specimen should be placed between two gauze squares moistened with sterile water or saline. Place these in a sterile screw-cap container.

3. Nails should be cleansed with 70% alcohol and then scraped deeply enough to obtain recently invaded nail tissue. Debris under the nail may be removed with a scalpel and placed between clean glass slides. If the dorsal plate appears diseased, scrape the outer surface and discard, and then collect scrapings through the diseased portion.

4. An evulsed nail should be placed in a sterile screw-cap container.

5. Scalp and hair specimens may be selected by placing the patient under an ultraviolet (UV) light (Wood's lamp). Hairs that are fluorescent, distorted, or fractured should be cultured. Culture of the basal portion of infected hair is recommended. Place at least 10 to 12 hairs in a sterile screw-cap container.

6. Room temperature storage of these specimens is sufficient if there is to be any delay in transport.

Ear

1. The specimen should be submitted on a swab in a bacterial transport medium.

2. Room temperature storage is recommended if there is to be any delay in transport.

Eye

1. Ocular specimens are usually collected by the physician and immediately inoculated to media at the bedside or in the office. If this is not possible, a swab or scraping of the corneal and/or conjunctival material may be submitted in a bacterial transport. Fluid or pus should be collected with needle and syringe and inoculated into bacterial transport.

2. Room temperature storage is recommended if there is to be any delay in transport.

Stool

1. Stool specimens may be submitted in sterile screw-cap stool culture preservative (C&S vial). Rectal swabs are not recommended because they are easily contaminated by yeasts from the perianal region or the vagina.

2. Refrigerate stool specimens if there is to be any delay in transport.

Fluids

1. Fluids (eg, pleural, peritoneal, joint) should be aspirated and placed into a sterile screw-cap container. For large volumes (ie, thoracic, pleural, or abdominal fluids), a well-mixed aliquot of 50 to 100 mL may be submitted.

2. Room temperature storage is recommended if there is to be any delay in transport.

Genitourinary Tract

1. Urine must be collected in such a manner as to prevent contamination with yeasts from the external urinary tract. First-morning clean-catch specimens or specimens obtained by catheterization are acceptable if proper cleansing procedures are used before collection. See Urine Specimens for instructions for collecting urine samples.

2. Refrigerate urine specimens if there is a delay in transportation.

3. Two swabs containing material from the vagina, cervix, or uterus should be inserted into a bacterial transport device. Refrigerated storage is recommended if there is to be any delay in transport.

Lower Respiratory Tract

1. Sputum should be collected as a first/early morning sample; a series of three to six specimens is recommended. Patients should brush their teeth, rinse out their mouths with water, and then produce material from deep cough.

2. Place bronchial washings in a sterile leakproof container for transport to the laboratory.

3. Induced specimens from patients who are not coughing are recommended. Transtracheal aspirations and bronchoscopy biopsies may be helpful.

4. Refrigerate respiratory secretions if delay in transportation is necessary.

Tissue

1. Tissue containing a portion of the wall, base, and center of the lesion should be obtained and placed between sterile moist gauze squares in a sterile container. Use sterile saline or sterile water to moisten the gauze. (Liver biopsy tissue should be placed directly into a tube of BHI broth.)

2. Place a small amount of tissue directly into 1 to 2 mL sterile saline or water in a sterile screw-cap container.

3. Room temperature storage is recommended if there is to be any delay in transport.

Thrush Lesions of Oral Cavity

1. Do not use swabs for collection. Use a tongue depressor that has been split in half along its long axis. Gently scrape the lesion with one-half of the tongue depressor. Scrape the material onto a sterile swab and place it into bacterial transport.

2. Room temperature storage is recommended if there is to be any delay in transport.