L/O/G/O

Pleural, peritoneal, pericardial & synovial fluids

culture2013-2014

بسم الله الرحمن الرحيم

Diagnostic Medical Microbiology-Laboratory Manual

Body Fluid Culture Aim of the testIsolate and identify pathogenic organisms from normally sterile body fluids and perform sensitivity test

Types of specimenAseptically aspirated body fluid (e.g., , synovial, peritoneal fluid).

Criteria of specimen rejectionInappropriate specimen transport device; mislabeled specimen; unlabeled specimen; specimen received after prolonged delay (usually more than two hour); specimen received in expired transport media.

Infection Of Sterile Body Fluidall body fluid are sterileCommon Pathogenic of Precarditis And Myocarditis Pleural FluidMycoplasma pneumoniae Staphylococcus aureusChlamydia trachomatis Streptococcus pneumoniae Mycobacterium tuberculosis Haemophilus influenzaeStaphylococcus aureus EnterobacteriacaeStreptococcus pneumoniae Pseudomonas spp.Enterobacteriacae and other gram negative Bacilli Anaerobic bacteriaFungi Mycobacterium tuberculosis

Coccidoides immitis Actinomyces spp.

Aspergillus spp. Peritoneal fluidCandida spp. Streptococcus pneumoniaeCryptococcus neoformans Group A streptococciHistoplasma capsulatum Enterobacteriacae Bones and joints Other gram negative bacilliStaphylococcus aureus Staphylococci Streptococcus pyogenes Neisseria gonorrheaeHaemophilus influenzae Chlamydia trachomatisStreptococcus pneumoniae FungiEnterobacteriacae Coccioides immitisMycobacterium spp Candida sppNeisseria gonorrheae

Pre specimen processing

Who will collect the specimen Physician

Quantity of specimen 1-5 mL is adequate, a larger quantity of fluid is better.

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.

Specimen processing

Specimen processing

Body fluids for culture should be concentrated by either filtration or high speed centrifugation.

Filtration of fluid through a 0.45 micrometer poresize membrane filter allows a greater volume of fluid to be processed and usually yield better results, then the filter should be cut aseptically into pieces, one of which is placed on chocolate agar for incubation in 5% carbon dioxide, one on MacConkey agar, on blood agar plate for aerobic incubation, and the last on a blood agar plate for anaerobic incubation.

Specimen processing

If fluid has been concentrated by centrifugation, the resulting sediment should be inoculated to an enrichment broth, blood, chocolate and MacConkey agars.

All fluids should be processed for direct microscopic examination, in general if one organism is seen per oil immersion field at least 105 organisms per milliliter of specimen are present.

Specimens for fungi should be examined by direct wet preparation or by preparing 10% KOH for visualization of fungi element from a wet preparation.

Acid Fast stain for Mycobacterium spp.

Post specimen processing Interfering factors:

Patient on antibiotic therapy. Improper sample collection.

Result reporting: Report Gram stain, KOH, and AFS 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 2-4 days. Negative culture will be reported out 1-2 days after the receipt of

the specimen.

L/O/G/O

Any Questions ?

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