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Hours of Service

Routine & STAT Services: Daily, 7 a.m. to 11 p.m.

Limited STAT Services: Daily, 24 hours

Routine Services

  • Bacteriology: Specimens requesting bacterial cultures are processed daily during regular service hours.
  • Mycobacteriology: Respiratory specimens are processed daily. All other specimens are processed Monday through Friday, excluding holidays. Acid fast stains are performed on all specimens except blood. Specimens received by 8am will be processed that day.
  • Parasitology: Routine procedures on stools are performed Monday through Friday. Specimens should be placed in the parasitology collection kit available on the wards or from Central Distribution. Malaria smears are processed and read daily.
  • Mycology: Specimens requesting fungal cultures will be processed daily during regular service hours.
  • Serology: Cryptococcal antigens on spinal fluid, syphilis serology, and rubella screens are performed daily, during regular service hours. All other tests are batched. Call Microbiology, 714-456-5439 for testing schedule.
  • Virology: Specimens for viral isolation are processed daily during regular service hours.
  • Molecular Microbiology: Not all tests are performed daily. Call microbiology, 714-456-5439 for testing schedule.

STAT Services

Available Daily, 24 hours

  • Bacterial Antigen Assay for Group A Streptococcus, Throat
  • Cryptococcal Antigen, Spinal Fluid
  • Enterovirus, CSF, by PCR
  • Gram stain
  • Group B Streptococcus, vaginorectal, by PCR
  • HIV Type 1 and Type 2 Antibodies/HIV 1 P24 Antigen Screen (limited to women in labor who have delivered without previous prenatal care, newborns of mothers who decline testing, patients in emergengy department, referral clients where patient needs immediate medical intervention, samples submitted through Occupational Health for employees exposed to body fluids)
  • Influenza Virus, Types A/B & RSV Antigen Detection by PCR (Nov. 1 to April 30)
  • Legionella Pneumophila Antigen, Urine
  • Malaria, EIA
  • Streptococcus pneumoniae Antigen, CSF and Urine

Available daily, 7 a.m. to 11 p.m.

  • Acid Fast Bacilli (AFB), direct smear
  • Fungal Direct Exam (Calcofluor White Stain)

General Guidelines – Specimen Collection

  1. Standard precautions and guidelines must be followed.
  2. Collect specimens prior to administering antimicrobial agents, whenever possible.
  3. Collect an adequate amount of specimen to decrease the chance of false-negative results.
  4. Collect the specimen with as little contamination as possible to insure that the sample will be representative of the infected site.
  5. If the specimen is collected through intact skin, cleanse the skin with ChloraPrep or Betadine.
  6. Submit specimens in sturdy, sterile leak proof screw-cap containers with lids that do not create an aerosol when opened.When collecting specimen with a swab, use the Culture Swab™. Place swab securely back into the container.Clearly label the specimen container with the patient’s name, identification number, date and time of collection. UNLABELED OR MISLABELED SPECIMENS ARE UNACCEPTABLE AND WILL NOT BE PROCESSED.
  7. ALL SPECIMENS MUST HAVE SOURCE AND/OR SPECIFIC SITE INDICATED. Specimens without source specified will result in processing delays and/or improper testing.
  8. Place specimen into a sealable plastic bag with a separate pouch for the transmittal.
  9. Provide clinical diagnosis so that proper isolation and identification methods are used.

General Guidelines – Specimen Transport

  1. Transport all specimens to the laboratory promptly.
  2. Refrigerate specimen at 2-8° C if there is a delay in delivery, with the following exceptions:Hold at room temperature*:
    • Blood cultures, including Isolator tubes
    • Anaerobic cultures
    • Specimens for Trichomonas vaginalis and Neisseria species.
    • Cerebrospinal fluid*Stool specimens for parasitology exam must be mixed with preservative and held at room temperature.

Consequences of poorly collected and/or poorly transported specimens include the failure to isolate the causative microorganism and the recovery of contaminants or normal microbial flora which may lead to improper treatment of the patient.

Special Collection Instructions

Blood Cultures

  • Two separate venipunctures, to collect two sets of blood cultures, each from a different site prior to initiation of antimicrobial therapy are recommended.
  • Blood culture bottles are available on the ward or from Central Distribution.
  • Clean the top of each bottle with an alcohol prep before and after inoculation.
  • Draw 20 mL of blood per venipuncture and inoculate 10 mL into each bottle of the blood culture set: BACTEC PLUS (aerobic/F) and BACTEC LYTIC (anaerobic/F).
  • Do not introduce air into the bottles.
  • Do not change needles between collection of blood and inoculation of bottles.
  • Indicate if fastidious organisms are suspected. Special media and/or extended incubation may be required. Contact Microbiology at 714-456-5439.
  • If fungemia or mycobacteria are suspected, also collect blood in an isolator tube.
  • If viremia is suspected, collect blood in a green top (sodium heparin) tube.
  • Transport immediately to the laboratory. 


  • Specimens must arrive at the laboratory by 8 a.m. for processing that day.
  • All specimens except blood are processed for smear and culture.
  • Smears on respiratory specimens are reported within 24 hours of receipt.
  • STAT direct smears are performed daily during regular service hours. 


  • Specimens must be delivered promptly to the laboratory.
  • Delay allows for the overgrowth of bacteria and rapidly growing saprophytic fungi and compromises the isolation of slower growing pathogens.


  • Instruct the patient to pass bowel movement into a clean container. Do not pass specimen into the toilet or water. Instruct the patient to add enough specimen to the container in the collection kit to reach the fill line. DO NOT FILL TO THE TOP OF THE CONTAINER. Specimens must be preserved while fresh. Submit three specimens, each collected on different days.
  • The following interfering substances reduce the organisms to very low numbers or they may temporarily eliminate them from the stool: antibiotics, bismuth, kaolin, barium sulfate, sulfonamides, antiprotozoal drugs, antihelminthic agents, oils, magnesium hydroxide and various enemas such as water, soap solutions, irritants and hypertonic salt solutions.


  • All specimens should be obtained as early as possible in the course of a patient’s illness.
  • When CSF is submitted for culture, a throat and stool specimen should also be sent for culture.
  • All specimens for viral isolation must be placed immediately in a sterile container and the container placed on wet ice (4° C). Deliver immediately to the Laboratory. 

Molecular Microbiology

  • For HIV (viral load), HCV and HBV PCR, collect blood in a pearl white-top Plasma Preparation Tube (PPT™).
  • For HIV DNA PCR, qualitative (infants only), collect blood in 3 pediatric lavender-top (EDTA) tubes.
  • Chlamydia/Gonorrhea PCR
    • Genital: Use chlamydia culture transport media and refrigerate after collection. Indicate specimen site (endocervix, vagina, urethra).
    • Urine (males only): Patient must not void for at least 2 hours prior to specimen collection.

Antimicrobial Susceptibility Testing

  • The primary battery of antimicrobics reported depends upon the organism isolated and the specimen source.
  • If the organism is susceptible to the agents on the primary batteries, no additional antimicrobics are reported.
  • Additional antimicrobics are reported for resistant organisms, or may be reported upon physician request.
  • For further information, call Microbiology at 714-456-5439.