What laboratory tests would be ordered for a patient presenting with easy bruising and fatigue?

From the Guidelines

For a patient presenting with easy bruising and fatigue, I would order a complete blood count (CBC) with differential, peripheral blood smear, coagulation studies (PT, PTT, INR), comprehensive metabolic panel (CMP), ferritin, vitamin B12, and folate levels, as well as von Willebrand screen and platelet function study, as these tests would help identify potential causes such as thrombocytopenia, coagulation disorders, anemia, leukemia, or vitamin deficiencies 1. These tests are essential in evaluating the patient's condition, as easy bruising and fatigue can be symptoms of various underlying disorders.

• The CBC would reveal abnormalities in blood cell counts, while coagulation studies would identify clotting disorders.
• The CMP would assess liver and kidney function, as dysfunction in these organs can contribute to bleeding tendencies.
• Vitamin levels are important since deficiencies in B12, folate, or iron can cause fatigue and, in some cases, bleeding issues.
• A von Willebrand screen and platelet function study would help diagnose von Willebrand disease or other platelet disorders, which can cause easy bruising 1. If the initial workup suggests a specific direction, additional specialized tests might include hemolysis markers (LDH, haptoglobin, reticulocyte count), bone marrow biopsy, or specific factor assays. This comprehensive approach allows for identification of common causes like immune thrombocytopenia, leukemia, liver disease, or vitamin deficiencies that could explain both the easy bruising and fatigue symptoms. It is also important to consider the patient's medical history, including any medications that may be contributing to the symptoms, as well as any family history of bleeding disorders 1. By ordering these tests, we can determine the underlying cause of the patient's symptoms and develop an effective treatment plan to improve their quality of life and reduce the risk of morbidity and mortality.

From the Research

Laboratory Tests for Easy Bruising with Fatigue

To evaluate easy bruising with fatigue, the following laboratory tests can be ordered:

• Complete blood cell count (CBC) to assess for anemia, thrombocytopenia, or other blood cell abnormalities 2, 3, 4
• Platelet count to evaluate for thrombocytopenia, which can cause easy bruising 2, 3, 4
• Prothrombin time (PT) and activated partial thromboplastin time (aPTT) to assess the coagulation pathway 2, 3, 4, 5, 6
• Peripheral blood smear to evaluate the morphology of blood cells 2, 3, 4
• Fibrinogen level to assess for coagulation factor deficiencies 3, 5
• Von Willebrand factor antigen, von Willebrand factor activity, and factor VIII assays if von Willebrand disease is suspected 2
• Template bleeding time to evaluate platelet function 2

Interpretation of Laboratory Results

Abnormal results from these tests may indicate:

• Thrombocytopenia, which can result from idiopathic thrombocytopenic purpura, disseminated intravascular coagulation, or other conditions 2
• Coagulation factor deficiencies, such as factor VIII or von Willebrand factor deficiency 2, 3, 4
• Platelet function disorders, such as qualitative platelet disorders 4
• Inherited bleeding disorders, such as von Willebrand disease or hemophilia A 2, 3, 4

Further Evaluation

If initial laboratory results are abnormal or if there is a high suspicion of a bleeding disorder, consultation with a hematologist is recommended 3. Additional specialized tests, such as mixing studies, inhibitor assays, or multimeric analysis of von Willebrand factor, may be necessary to diagnose specific bleeding disorders 2, 4, 5.