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Cell Count and Differential, body fluid
|Test group||Cell Count and Differential|
|Performed by||Parnassus Hematology|
|In House Availability||Test available 24 hours per day 7 days per week|
|Method||Hemocytometer for cell count, Wright stained cytospin preparation for differential|
|Collection Instructions||Deliver samples IMMEDIATELY to the laboratory. Specimen label must contain the date and time the sample was collected and the legible name of the person who collected the sample.|
|Container type||Lavender top or Dark Green top|
|Amount to Collect||See preferred volume|
|Sample type||Body Fluid|
|Preferred volume||> 2 mL fluid|
|Min. Volume||1 mL fluid|
|UCSF Rejection Criteria||Sample received in a syringe with needle attached.|
|Processing notes||Deliver sample immediately to Hematology for testing.|
|Units||x109/L (this is equivalent to x103/mm3 or x103/µL)|
|Critical value||Samples positive for microorganisms from normally sterile sites|
|Synonyms||Body fluid cell count; pleural fluid cell count; peritoneal fluid cell count; synovial fluid cell count; Pericardial fluid cell count; joint fluid cell count|
|Stability||Pleural, Pericardial, Peritoneal & Bronchoalveolar Lavage (BAL): Delay in analysis will cause cell lysis, cellular degeneration, and bacterial growth which can affect the test results. Samples received two (2) hours after collection are accepted but results modified as follows: "Sample stability period exceeded or collection time unknown. Cellular degeneration can begin within one hour of collection, interpret results accordingly. See Lab Manual for Moffitt-Long and Mt. Zion for more information".
Synovial: Delayed interpretation of synovial fluids may lead to false-negative findings. Studies have shown that WBC's disintegrate with time. Based on a small in-house study performed on refrigerated samples, WBC decreased by ~10% at 6 hours; although the proportion of cell loss may depend on the types of WBC's present. Studies have also shown that crystals such as CPPD dissolve with time. MSU crystals remained stable for several weeks.
|Turn around times||STAT 1 hour. Routine 4 hours|
|Additional information||Cell counts and differentials on biliary fluid have not proven to be useful, due to the disruption of the cellular elements by bile acids, and are thus not offered for this specimen type. An assessment for the presence of WBC in biliary drainage fluid is included in the examination of biliary fluid for crystals. An examination for crystals is automatically ordered at an additional charge on Joint fluids.
Note: Cell differentials are performed on a concentrated sample. Therefore a differential can be reported even if the reported WBC is 0 x 109/L
|Last Updated||3/24/2013 8:11:25 PM|
If you have additional questions regarding this test, please call: 415-353-1667