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Medical Author:

Siamak T. Nabili, MD, MPH

Siamak T. Nabili, MD, MPH

Dr. Nabili received his undergraduate degree from the University of California, San Diego (UCSD), majoring in chemistry and biochemistry. He then completed his graduate degree at the University of California, Los Angeles (UCLA). His graduate training included a specialized fellowship in public health where his research focused on environmental health and health-care delivery and management.

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Medical Editor:

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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Low platelet count is often discovered incidentally during routine blood work. Platelets are a component of the complete blood count (CBC) along with white blood cell and red blood cell counts. Pseudothrombocytopenia can be eliminated by repeating the CBC.

Investigation for low platelet count includes a comprehensive medical history and physical examination by the doctor. Review of all the medications, family history, and personal history of cancers, drug and alcohol use, bleeding problems, and other medical conditions (rheumatic diseases, liver problems, kidney disease) needs to be included in this evaluation. An enlarged spleen (splenomegaly), petechiae, and purpura are typically looked for on the physical examination in these patients.

Further diagnostic investigation for thrombocytopenia relies on a detailed review of the other values on the CBC (red cell count, hemoglobin, white blood cell count, mean platelet volume or MPV), the comprehensive blood chemistry panel (kidney function, liver function, electrolytes), blood coagulation panel (other components of the clotting system), and review of the blood smear under the microscope (looking for fragmented red cells, shape and size of white cells, red cells, platelets).

Tests for antibodies and other assays may be performed in cases in which HIT or ITP are suspected. Bone marrow biopsy is sometimes done to evaluate for aplastic anemia, leukemia, lymphoma, or metastatic cancer to the bone marrow.

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