Policy Statement	Core Laboratory Personnel are responsible for insuring the specimen submitted for testing is acceptable and the procedure for performing this assay is not violated.
Purpose	This procedure provides technical instruction for understanding and performing an acceptable outcome for erroneous platelet results due to clumped, giant, or platelet satellitosis.
Scope	This procedure applies to testing personnel authorized to perform testing using the Sysmex XE-5000 analyzer while identifying possible erroneous platelet results.
Responsibility	All authorized personnel are responsible for following procedural guidelines and insuring good laboratory practice is followed.
Related Documents	Sysmex Operators XE-5000 Main Manual Sysmex Operators XE-5000 IPU Manual Sysmex Training Manual

CLUMPED, GIANT PLATELETS AND PLATELET SATELLITOSIS PROCEDURE

PRINCIPLE

Certain blood samples may exhibit platelet abnormalities such as giant platelets or platelet satellitosis or clumped platelets. Specimens with any of these abnormalities run on automated instruments may produce erroneous results. If any of these platelet abnormalities are present in a specimen, then alternate testing methods must be used.

PROCEDURE

Specimens with platelet abnormalities can be detected by several methods. The primary method would be by observing the giant or clumped platelets or platelet satellitosis on a blood smear while the differential is being done. Another would be by noting an abnormal platelet flag/message or action code on the Sysmex analyzer. If an abnormal histogram or platelet count is noted on the automated cell counters, the abnormality must be confirmed by looking at a blood smear. Having ascertained that a platelet abnormality does exist, several steps must be followed to obtain accurate results:

A)	If clumped platelets are suspected, a smear should be reviewed paying particular attention to the top, bottom and feathered edges of the smear. In the event that a CBC only is ordered, the coded comment CLCLUMP( The platelets appear clumped on the smear, The platelet count may be falsely decreased. In some patients the anticoagulant EDTA will cause platelet clumping, drawing a specimen in citrate anticoagulant may reduce or eliminate this effect) should be entered under the platelet count. This will alert the physician to order a PLTC, a platelet count in a sodium citrate tube. The Meditech computer system will automatically perform the calculation to correct for the dilution factor in the sodium citrate tube.

NOTE: If clumped platelets are noted on any smear review, order a manual smear and enter the letter C in the PLT Estimate field. This will enter a result platelet clumps noted and alert the physician in EMR that the patient has clumped platelets and the count may be affected.

If platelet satellitosis is present, the fresh specimen should be collected in a sodium citrate tube and run immediately.

REFERENCES

Koepke, J.A.: 1981. Tips on Technology. MLO:15

Mohler, Emile R., M.D., Personal Communication

Onder, O., Weinstein, A., and Hoyer, L.W.: 1980, Blood 56: 177-182z