A low platelet count means that the number of platelets in the peripheral blood is less than 100,000 per microliter.

Clinically, most patients with isolated thrombocytopenia do not have leukemia. Only a very small number of patients with isolated thrombocytopenia are ultimately diagnosed with leukemia.

The most common disease causing thrombocytopenia in clinical practice is immune thrombocytopenic purpura, which is an autoimmune disease. Due to the imbalance of the immune system, auto - antibodies against platelets are produced, leading to excessive destruction of platelets in the peripheral blood. Patients will experience thrombocytopenia and a series of bleeding symptoms.

Secondly, other autoimmune diseases, such as systemic lupus erythematosus, rheumatoid arthritis, antiphospholipid antibody syndrome, etc., can also present with thrombocytopenia. However, in addition to low platelet counts, these patients often have other symptoms.

Of course, in clinical practice, a very small number of leukemia patients may present solely with a low platelet count and are ultimately diagnosed with acute leukemia through bone marrow examination. But this is a very rare situation.