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Difficulty: MediumHematology and Oncology

Match each patient's clinical vignette with the most likely corresponding coagulation profile and mixing study result.

  • A 28-year-old woman with systemic lupus erythematosus presents with an unprovoked deep vein thrombosis and a history of two first-trimester miscarriages.Normal PT, Prolonged aPTT, normal platelet count; aPTT does NOT correct with a 1:1 normal plasma mixing study
  • A 19-year-old woman evaluates for heavy menstrual bleeding and a history of prolonged epistaxis and gingival bleeding following a tooth extraction.Normal PT, Normal or slightly prolonged aPTT, normal platelet count, prolonged bleeding time
  • A 7-year-old boy is brought to the emergency department with a large, painful hemarthrosis of the right knee after a minor fall. His maternal uncle has a severe bleeding disorder.Normal PT, Prolonged aPTT, normal platelet count, normal bleeding time; aPTT CORRECTS with a 1:1 normal plasma mixing study
  • A 55-year-old man undergoing induction chemotherapy for acute promyelocytic leukemia develops diffuse ecchymoses and persistent oozing from venipuncture sites.Prolonged PT, Prolonged aPTT, decreased platelet count, decreased fibrinogen level

Answer

The lupus patient matches with the non-correcting aPTT (APS). The young woman with mucosal bleeding matches with prolonged bleeding time (vWD). The boy with hemarthrosis matches with the correcting aPTT (Hemophilia). The APL patient matches with consumptive coagulopathy (DIC).
Each clinical scenario presents classic features of a specific hematologic disorder, which predictably correlates with a distinct laboratory profile. Distinguishing between primary and secondary hemostatic defects, recognizing the consumptive nature of DIC, and utilizing mixing studies to identify inhibitors leads to the correct laboratory pairings.

Step-by-Step Solution

1
Analyze the clinical vignette for the 28-year-old woman with lupus.
Identified signs of Antiphospholipid syndrome (thrombosis, recurrent miscarriages).
Recognizing the clinical triad of APS helps anticipate the presence of a lupus anticoagulant.
2
Correlate Antiphospholipid syndrome with laboratory findings.
Matched with prolonged aPTT that does not correct on mixing study.
Lupus anticoagulant is an inhibitor, meaning the addition of normal plasma will fail to correct the prolonged aPTT.
3
Analyze the clinical vignette for the 19-year-old woman.
Identified signs of von Willebrand disease (mucosal bleeding, menorrhagia).
Mucosal bleeding is a hallmark of primary hemostasis defects.
4
Correlate von Willebrand disease with laboratory findings.
Matched with prolonged bleeding time and potentially prolonged aPTT.
Von Willebrand factor mediates platelet adhesion (prolonging bleeding time) and stabilizes Factor VIII (potentially prolonging aPTT).
5
Analyze the clinical vignette for the 7-year-old boy.
Identified signs of Hemophilia (deep tissue bleeding, hemarthrosis, X-linked inheritance).
Hemarthrosis points to a secondary hemostasis defect, and the family history suggests Hemophilia A or B.
6
Correlate Hemophilia with laboratory findings.
Matched with prolonged aPTT that corrects on mixing study.
Hemophilia is a deficiency of Factor VIII or IX. Adding normal plasma replaces the missing factor and corrects the aPTT in vitro.
7
Analyze the clinical vignette for the 55-year-old man.
Identified signs of Disseminated Intravascular Coagulation (DIC) triggered by Acute Promyelocytic Leukemia.
APL granules contain procoagulants that frequently trigger severe DIC when released into the bloodstream.
8
Correlate DIC with laboratory findings.
Matched with prolonged PT/aPTT, decreased platelets, and low fibrinogen.
DIC causes widespread systemic consumption of platelets, fibrinogen, and all coagulation factors.

Key Concept

The diagnosis of bleeding and thrombotic disorders relies on distinguishing primary hemostasis defects (prolonged bleeding time) from secondary hemostasis defects (prolonged PT/aPTT). Mixing studies successfully differentiate factor deficiencies (which correct) from acquired inhibitors (which do not correct).
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Topics

Hematology and Oncology

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