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→Platelet Number
Platelet numbers may be rapidly estimated by examination of a stained bloof smear, of quatnifies by manual counting techniques or automated haematology analysers. To estimate the platlet number using a blood smear, the average number of platelets in twn oil-immersion fields should be counted and the mean multiplied by 15.
Platelet numbers may be rapidly estimated by examination of a stained bloof smear, of quatnifies by manual counting techniques or automated haematology analysers. To estimate the platlet number using a blood smear, the average number of platelets in twn oil-immersion fields should be counted and the mean multiplied by 15.
The reference range given for platelet number is usually around 200-500x10<sup>9</s>/l, although this varies depending on the laboratory used. Clinical signs due to thrombocytopenia are not commonly encountered until the platelet count drops below 50X10<sup>9</sup>/l, and spontaneous bleeding only occurs with counts lower than 20X10<sup>9</sup>/l. These cut-offs are lowered if platelet function is concurrently affected, for example by the use of non-steroidal anti-inflammatory drugs.
The reference range given for platelet number is usually around 200-500x10<sup>9</sup>/l, although this varies depending on the laboratory used. Clinical signs due to thrombocytopenia are not commonly encountered until the platelet count drops below 50X10<sup>9</sup>/l, and spontaneous bleeding only occurs with counts lower than 20X10<sup>9</sup>/l. These cut-offs are lowered if platelet function is concurrently affected, for example by the use of non-steroidal anti-inflammatory drugs.
Thrombocytopenia alone rarely causes clinical signs until the platelet count drops
Thrombocytopenia alone rarely causes clinical signs until the platelet count drops
The platelet count is of value when assessing bleeding disorders that occur with thrombocytopenai, uremia, liver disease or malignancies and for monitoring the course of disease associated with bone marrow failure. This test is indicated when the estimated platelet count on a blood smear appears abnormal. It is also part of a coagulation profile or work up. the mean platelet volume (MPV) is somtimes used in conjunction with a platelet count. The MPV indicates the uniformitiy of the size of the platelte population and is used for the differential diagnosis of throbocytopenia.
The platelet count is of value when assessing bleeding disorders that occur with thrombocytopenai, uremia, liver disease or malignancies and for monitoring the course of disease associated with bone marrow failure. This test is indicated when the estimated platelet count on a blood smear appears abnormal. It is also part of a coagulation profile or work up. the mean platelet volume (MPV) is somtimes used in conjunction with a platelet count. The MPV indicates the uniformitiy of the size of the platelte population and is used for the differential diagnosis of throbocytopenia.