From the Guidelines
The workup for anemia and thrombocytopenia should begin with a complete blood count with differential, peripheral blood smear, reticulocyte count, and comprehensive metabolic panel to assess the severity and potential causes, as recommended by the most recent guidelines 1. The initial evaluation should include a thorough history and physical examination, with special attention to bleeding symptoms, medication history, and risk factors for underlying conditions such as HIV or hepatitis 1.
- Key components of the initial workup include:
- Complete blood count with differential
- Peripheral blood smear
- Reticulocyte count
- Comprehensive metabolic panel
- Additional first-line tests may include:
- Coagulation studies (PT/INR, PTT)
- Direct Coombs test
- Iron studies (ferritin, iron, TIBC)
- Vitamin B12 and folate levels
- LDH and haptoglobin to evaluate for hemolysis A bone marrow aspiration and biopsy may be necessary if the initial workup is inconclusive or if a primary bone marrow disorder is suspected 1.
- Specific testing should be directed by clinical presentation, such as:
- ADAMTS13 activity for suspected TTP
- DIC panel for suspected consumptive coagulopathy
- HIV and hepatitis testing in at-risk patients The presence of both anemia and thrombocytopenia together suggests potential diagnoses such as myelodysplastic syndrome, leukemia, disseminated intravascular coagulation, thrombotic microangiopathies (TTP/HUS), or severe vitamin deficiencies 1. Management depends on the underlying cause, but may require urgent intervention if the patient is hemodynamically unstable or has significant bleeding, with transfusion support with packed red blood cells and platelet transfusions as needed 1.
From the Research
Workup for Anemia and Thrombocytopenia
The workup for anemia and thrombocytopenia involves several steps to determine the underlying cause of these conditions.
- Evaluation of the patient's medical history and physical examination to identify any underlying conditions that may be contributing to the anemia and thrombocytopenia 2, 3.
- Laboratory tests, such as complete blood count (CBC), blood film examination, and reticulocyte count, to confirm the diagnosis of anemia and thrombocytopenia 2, 3.
- Additional tests, such as vitamin B12 level, methylmalonic acid level, and lactate dehydrogenase (LDH) level, to help distinguish between different causes of thrombocytopenia, including pseudo-TTP and TTP 2.
- Examination of the blood film to identify any abnormalities in the platelets or red blood cells 4.
Distinguishing Between Pseudo-TTP and TTP
To distinguish between pseudo-TTP and TTP, the following parameters can be used:
- Reticulocytopenia, which suggests B12 deficiency 2.
- LDH level above 2500 IU/L, which is relatively uncommon in TTP and should suggest consideration of B12 deficiency 2.
- Evaluation of the patient's clinical presentation, including volume loss and bleeding, to determine if a multifactorial pathogenesis is contributing to the laboratory abnormalities 2.
Management of Thrombocytopenia
The management of thrombocytopenia depends on the underlying cause and severity of the condition.
- Platelet transfusion may be indicated in patients with impaired platelet production or increased platelet destruction 3, 5.
- Treatment of the underlying disease, such as sepsis or trauma, can also increase platelet counts 5.
- Immune thrombocytopenia may require immunomodulatory treatment 5.
- Heparin-induced thrombocytopenia requires alternative anticoagulation at a therapeutic dose 5.
- Prophylactic platelet transfusions may be considered in patients with severe thrombocytopenia or those undergoing invasive procedures 5, 4.