Pleural, peritoneal, pericardial & synovial fluids culture بسم الله الرحمن الرحيم Pleural, peritoneal, pericardial & synovial fluids culture 2014-2015 Diagnostic Medical Microbiology-Laboratory Manual

Body Fluid Culture 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). Criteria of specimen rejection Inappropriate specimen transport device; mislabeled specimen; unlabeled specimen; specimen received after prolonged delay (usually more than two hour); specimen received in expired transport media. Pleural Fluid a collection of fluid in the plural space, normally found between the lung and the chest wall the fluid usually contains few or no cells and has a consistency similar to that of serum but with a lower protein content. When excess amount of this fluid are present it is called an effusion or transudate and is often the result of cardiac hepatic or renal disease. Peritoneal Fluid A small amount of fluid in the peritoneal cavity that maintains moistness of the surface of the peritoneum, normal peritoneal fluid may contain as many as 300 white blood cells per milliliter, but the protein content and specific gravity of the fluid are low. During an infections or inflammatory process increased amount of fluid accumulated in the peritoneal cavity a condition called ascities. The fluid often called ascitic fluid contains an increased number of inflammatory cells and an elevated protein level. Pericardial Fluid The area between the epicardium which is the membrane surrounding the heart muscle and the pericardium is called pericardial space and normally contain 15 to 20 ml of clear fluid. Joint fluid The fluid surrounding the joints and work as lubricant for joints.

Infection Of Sterile Body Fluid all body fluid are sterile Common Pathogenic of Precarditis And Myocarditis Pleural Fluid Mycoplasma pneumoniae Staphylococcus aureus Chlamydia trachomatis Streptococcus pneumoniae Mycobacterium tuberculosis Haemophilus influenzae Enterobacteriacae Pseudomonas spp. Enterobacteriacae and other gram negative Bacilli Anaerobic bacteria Fungi Coccidoides immitis Actinomyces spp. Aspergillus spp. Peritoneal fluid Candida spp. Cryptococcus neoformans Group A streptococci Histoplasma capsulatum Bones and joints Other gram negative bacilli Staphylococci Streptococcus pyogenes Neisseria gonorrheae Coccioides immitis Mycobacterium spp Candida spp

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.

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