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. | 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. |