Culture, Bacterial Various Sites (Anal/Genital, Ear, Eye, Skin, Wound, Blood, Sputum, Stool, Throat/Nasopharyngeal, Urine)



To identify pathogenic bacterial organisms as an indicator for appropriate therapeutic interventions for multiple sites of infection, sepsis, and screen for methicillin-resistant Staphylococcus aureus (MRSA).

Patient Preparation
There are no food, fluid, or activity restrictions unless by medical direction. Whenever possible, specimens for culture should be collected before antimicrobial therapy begins as these medications will delay or inhibit growth of pathogens. As appropriate, provide the required urine collection container and specimen collection instructions.

Normal Findings

SiteTraditional Culture MethodNormal Findings
Anal/genital, ear, eye, skin, and woundCulture aerobic and/or anaerobic on selected media; cell culture followed by use of direct immunofluorescence, next generation sequencing, nucleic acid amplification, pathogen specific polymerase chain reaction (PCR), and DNA probe assays (e.g., Gen-Probe) are available for identification of Neisseria gonorrhoeae, Streptococcus agalactiae (group B streptococcus [GBS]), and Chlamydia trachomatisCulture, negative: No growth of pathogens
Culture-enhanced PCR or other DNA assays, negative: None detected
BloodGrowth of organisms in standard culture media identified by radiometric or infrared automation, by manual reading of subculture, next generation sequencing, or pathogen specific PCRNegative: No growth of pathogens
SputumAerobic culture on selective and enriched media; microscopic examination of sputum by Gram stain, next generation sequencing, or pathogen specific PCRThe presence of normal upper respiratory tract flora should be expected. Tracheal aspirates and bronchoscopy samples can be contaminated with normal flora, but transtracheal aspiration specimens should show no growth. Normal respiratory flora include Neisseria catarrhalis, Candida albicans, diphtheroids, alpha-hemolytic streptococci, and some staphylococci. The presence of normal flora does not rule out infection. A normal Gram stain of sputum contains polymorphonuclear leukocytes, alveolar macrophages, and a few squamous epithelial cells
StoolCulture on selective media for identification of pathogens usually to include Salmonella, Shigella, Escherichia coli 0157:H7, Yersinia enterocolitica, and Campylobacter; latex agglutination or enzyme immunoassay for Clostridioides difficile (A and B toxins). Next generation sequencing or pathogen-specific PCR may be used to identify bacterial, protozoan, or viral pathogensNegative: No growth of pathogens. Normal fecal flora is 96% to 99% anaerobes and 1% to 4% aerobes. Normal flora present may include Bacteroides, Candida albicans, Clostridioides difficile, Enterococcus, Escherichia coli, Proteus, Pseudomonas, and Staphylococcus aureus
Throat/nasopharyngealAerobic culture, next generation sequencing, or pathogen-specific PCRNo growth
UrineCulture on selective and enriched media; next generation sequencing, or pathogen-specific PCRNegative: No growth

Critical Findings and Potential Interventions

    Anal/Genital, Ear, Eye, Skin, and Wound Culture
  • Listeria in genital cultures (Listeriosis in pregnant women may result in premature birth, miscarriage, or stillbirth. The earlier in pregnancy the infection occurs, the more likely that it will lead to miscarriage or fetal death. After 20 weeks’ gestation, listeriosis is more likely to cause premature labor and birth.)
  • Methicillin-resistant Staphylococcus aureus in skin or wound cultures
  • Group B streptococcus (GBS) in urine or anal/genital cultures
    Blood Culture
  • Positive findings in any sterile body fluid such as blood
  • Corynebacterium diphtheriae
  • Legionella
  • Bacterial pathogens: Campylobacter, Clostridioides difficile, Escherichia coli including 0157:H7, Listeria, Rotavirus (especially in pediatric patients), Salmonella, Shigella, Vibrio, Yersinia, or parasites Acanthamoeba, Ascaris (hookworm), Cyclospora, Cryptosporidium, Entamoeba histolytica, Giardia, and Strongyloides (tapeworm), parasitic ova, proglottid, and larvae.
  • Culture: Growth of Corynebacterium or MRSA
  • Gram-negative extended spectrum beta lactamases Escherichia coli or Klebsiella
  • Gram-negative Legionella
  • Gram-positive Vancomycin-resistant Enterococci

Timely notification to the requesting health-care provider (HCP) of any critical findings and related symptoms is a role expectation of the professional nurse.

Specific infectious organisms are required to be reported to local, state, and national departments of health. Lists of specific organisms may vary among facilities. State health departments provide information regarding reportable diseases, which can be accessed at each state health department Web site. The CDC provides information regarding national notifiable diseases at

Assess for signs and symptoms of sepsis or development of septic shock to include change in body temperature (greater than 101.3°F or less than 95°F); decreased systolic blood pressure (less than 90 mm Hg); increased heart rate (greater than 90 beats/min); sudden change in mental status (restlessness, agitation, or confusion); significantly decreased urine output (less than 30 mL/hr); increased respirations (greater than 20 breaths/min); change in extremities (pale, mottled, and/or cyanotic in appearance); decreased or absent peripheral pulses.

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