1. Cerebrospinal fluid Culture
&
Body Fluid Culture

2. Indications
Mainly in Suspected cases of meningitis.
See video

3. Aim of the test
Diagnosis of the bacteria or fungal meningitis by microscopic examination and culture with identification and susceptibility test of the isolated organism.
commensals

4. Specimen collection
Explain procedure to the patient and obtain written consent.
See video

5. Quantity of specimen
3 ml of CSF is sufficient for culture.
Time relapse before processing the sample
CSF is an emergency specimen and should be processed immediately.
Storage: Room temperature
The sample is submitted in 3 tubes: chemistry, microscopic, culture sensitivity.

6. Specimen processing Media Two Blood Agar Chocolate Agar MacConkey Agar
Fluid Thioglycollate

7. Culturing procedure
As a general rule in CSF and body fluid specimens for culture
Centrifuge clear specimen and inoculate plates and do staining from sediments.
Turbid specimens may not be centrifuged.

9. Result reporting
Results of the microscopy and all positive cultures of CSF are reported immediately to the treating physician.
Negative bacterial results are sent out 72 hours after the CSF is received.
Examine all plates and broth medium for growth after 24 hrs.
If no visible growth reincubate.
Check all plate daily and discard after 7 days especially if gram stain was +
Generally +ve culture indicate pathogens

10. Turn around time
Gram stain result is reported within 30 minutes of specimen receipt
Positive Culture results = 3- 5 days
Negative Culture results = 2-3 day

11. Additional information
Several antigen detection methods are available for capsular antigen of H. influenzae, N. meningitidis, S. pneumoniae and Group B streptococci in CSF which showed specificity and sensitivity of about %.
The routine culture for CSF does not include all organisms mentioned in the above table.

12. Viral we test mainly: HSV and Enterovirus
Finding bacteria does not necessarily mean the infection is contagious, unless it is meningococcal meningitis
Viral we test mainly: HSV and Enterovirus
Fungal we test for Candida and Cryptococcus.
Herpes simplex virus

13. Body Fluid Culture

14. Body Fluid Culture This means
Culture of Body Fluid such as peritoneal, pericardial, plural, ascitic, synovial.
Aim of the test
Isolate and identify pathogenic organisms from normally sterile body fluids and perform sensitivity test.
Types of specimen
Aseptically aspirated body fluid (e.g., synovial, peritoneal fluid, pericardial fluid, and pleural fluid ).

15. Patient preparing
Explain procedure to the patient and obtain written consent.
Swab skin over the site of puncture with 2% tincture of iodine in concentric circles.
Iodine should remain in contact with skin for at least 1 minute prior to puncture to ensure complete antisepsis.
Before puncture, 70% alcohol is used to remove iodine from skin.

16. Specimen collection
Contamination with normal microbiota from skin, rectum, vaginal tract, or other body surfaces should be avoided.
Indicate the specific source and pertinent clinical history on the request form.
See video

17. Quantity of specimen: 1-5 mL is adequate.
Time relapse before processing the sample
Body fluids should be treated as CSF specimens and should processed immediately.
Storage
Maintain specimen at room temperature. Do not refrigerate.
Media
Blood Agar (2 plates)
Chocolate Agar,
MacConkey Agar
Thioglycollate broth

18. Specimen processing

19. Result reporting Report Gram stain finding as an initial report.
Report the isolated pathogen and its sensitivity pattern as a final report.
Turn around time:
Gram stain and wet mount results should be available 1 hour after specimen receipt.
Isolation of a possible pathogen can be expected after 2-3 days.
Negative culture will be reported out 1-2 days after the receipt of the specimen.