Aerobic Bacterial Culture, General

Methodology: 
Culture
Performed: 
Monday - Friday
Use: 
This test is used to isolate and identify potentially pathogenic aerobic organisms. A susceptibility test will be performed at an additional charge when organisms isolated meet microbiologic criteria for clinical significance.
 
This test includes isolation and identification (additional CPT codes) of potential aerobic pathogens and drug susceptibility tests (additional charge). Performing a Gram stain (additional test) is recommended. CPT coding for microbiology and virology procedures often cannot be determined before the culture is performed.
 

Limitations

Only rapid-growing, nonfastidious aerobic organisms can be recovered and identified by routine methods. Only organisms that predominate will be identified. Unless specifically requested by the physician, fastidious organisms may not be isolated. Anaerobic, fungal, and mycobacterial pathogens should be considered, and appropriate cultures requested if clinically indicated. The procedure will not detect Chlamydia, viruses, fungi or mycobacteria.
Specimen Requirements: 
Important: Sterile preparation of the aspiration site is required.
 
Gram-staining is recommended with all anaerobic cultures (additional charge).
 
The requisition form must state:
  • The specific site of the specimen;
  • The age of patient;
  • The current antibiotic therapy;
  • The patient's clinical diagnosis; and
  • The time of collection.

Inclusion of the patient's current antibiotic therapy and clinical diagnosis may aid the laboratory in evaluating the specimen and work-up of the culture.

If an unusual organism is suspected, this information must be specifically noted on the request form (e.g., Nocardia); this may result in additional charges.

Specimens from other sources, such as genital, stool, urine, upper and lower respiratory specimens, cannot be cultured with this test. If specimens are incorrectly submitted with an order for aerobic bacterial culture, the laboratory will process the specimen for the test based on the source listed on the request form. The client will not be telephoned to approve this change, but the change will be indicated on the report.

Type: Pus or other material properly obtained from a body site (abscesses, eyes, tissue, wounds). Do not submit syringes with needles attached.

Container/Tube: Sterile screw-cap container or bacterial swab transport
 

Sample Volume: Swab or 0.5 mL of aseptically aspirated pus or tissue

Storage: Store specimens at room temperature.
 
Stability (collection to time of analysis/testing): 
  • Ambient: Unstable
  • Refrigerated: Unstable
  • Frozen: 14 days
Rejection Criteria:
  • Improper labeling
  • Specimen received in grossly leaking transport container
  • Specimen received in expired transport media
  • Specimen received after prolonged delay (usually more than 72 hours)
Reference Values: 

Reference Intervals

No growth, routine/normal skin flora, routine/normal body site flora

Wounds often become colonized by multiple Gram-negative rods and mixed culture results are common. A simultaneous Gram stain should always be prepared and performed (additional charge) to facilitate interpretation.

Eye: Routine flora of the eye may include Corynebacterium sp (diphtheroids), Staphylococcus epidermidis, saprophytic fungi, Moraxella (Branhamella) catarrhalis, Moraxella sp, Streptococcus sp (nonhemolytic) and Gram-negative rods (rare). Abnormal ocular flora include:
  • Haemophilus influenzae;
  • Haemophilus aegyptius;
  • Streptococcus pneumoniae;
  • Staphylococcus aureus; 
  • Pseudomonas aeruginosa;
  • Bacillus subtilis; 
  • Neisseria gonorrhoeae; and
  • Mycobacterium chelonae.
Wound: Routine skin flora may include:
  • Coagulase-negative staphylococci;
  • Corynebacterium sp (diphtheroids); and
  • α-streptococci (Streptococcus viridans or viridans streptococci).
CPT Code (s): 
87070
Notes: 

UFHPL Test #: 78000

Eye: The major modes of transmission of disease to the conjunctiva include the hands, airborne fomites, and spread for adjacent adnexal infections. Eye infections include eyelid infections, blepharitis, dacryocystitis, orbital cellulitis, conjunctivitis, keratitis, endophthalmitis retinitis, and chorioretinitis. Pinkeye is caused by adenovirus. It presents as bilateral conjunctivitis with a sudden onset. Herpes simplex and zoster present as periorbital or corneal infections. Nontuberculous mycobacterial keratitis may occur following trauma or surgery accompanied by the use of local corticosteroids.1

Wound (See Table Below): Susceptibility testing is usually performed. The majority of bacteria infecting surgical wounds are common airborne microörganisms.2 Effective treatment of wound infection usually includes drainage, removal of foreign bodies, infected prosthetic devices, and retained foreign objects such as suture material. Suction irrigation may be helpful in resolving wound infections. Species commonly recovered from wounds include Escherichia coli, Proteus sp, Klebsiella sp, Pseudomonas sp, Enterobacter sp, enterococci, other streptococci, Bacteroides sp, Prevotella sp, Clostridium sp, Staphylococcus aureus, and coagulase-negative Staphylococcus.

Classification of Soft-tissue Infections

Tissue Level

Common Surgical Pathogens

S pyogenes

S aureus

C perfringens

Mixed Bacteria

Staph &
Strep

Enteric

Adapted from Ahrenholz DH, “Necrotizing Soft Tissue Infections,” Surg Clin North Am, 1988, 68(1):199-214.

Epidermis

Ecthyma contagiosum

Scalded-skin syndrome

 

Possibly impetigo

 

Dermis and
subdermis

Erysipelas/
Cellulitis

Folliculitis/
Abscess

Abscess/
Cellulitis

Meleny ulcer (synergistic gangrene)

Tropical ulcer

Fascial planes

Strep
gangrene

Carbuncle

Fasciitis

Necrotizing
fasciitis

Muscle tissue

Strep
myositis

Muscular abscess/
pyomyositis

Myonecrosis

Nonclostridial myonecrosis

Footnotes

  1. Bullington RH Jr, Lanier JD, Font RL. Nontuberculous mycobacterial keratitis. Report of two cases and review of the literature. Arch Ophthalmol. 1992 Apr; 110(4):519-524. PubMed 1562261
  2. Whyte W, Hambraeus A, Laurell G, Hoborn J. The relative importance of the routes and sources of wound contamination during general surgery. II. Airborne. J Hosp Infect. 1992 Sep; 22(1):41-54. PubMed 1358946

References

  • Baker AS. Ocular infections: Clinical and laboratory considerations. Clin Microbiol Newsl. 1989; 11:97-101.
  • Cheadle WG. Current perspectives on antibiotic use in the treatment of surgical infections. Am J Surg. 1992 Oct; 164(4A Suppl):44S-47S. PubMed 1443360
  • Goldstein EJ. Management of human and animal bite wounds. J Am Acad Dermatol. 1989 Dec; 21(6):1275-1279. PubMed 2685062
  • Jones DB, Leisegang TJ, Robinson NM. Cumitech 17. In: Washington JA, ed. Laboratory Diagnosis of Ocular Infections. Washington, DC: ASM Press;1981 (review).
  • Kligman EW. Treatment of otitis media. Am Fam Physician. 1992 Jan; 45(1):242-250. PubMed 1728094
  • Macknin ML. Respiratory infections in children. What helps and what doesn't? Postgrad Med. 1992 Jan; 92(2):242-250. PubMed 1495881
  • Pollack AV, Evans M. Microbiologic prediction of abdominal surgical wound infection. Arch Surg. 1987 Jan; 122(1):33-37. PubMed 3541852
  • Randall DA, Fornadley JA, Kennedy KS. Management of recurrent otitis media. Am Fam Physician. 1992 May; 45(5):2117-2123. PubMed 1575107
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