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Zorluk: OrtaHematology and Oncology

Match each clinical presentation with the most likely corresponding coagulation panel findings.

  • A 14-year-old boy with a history of recurrent hemarthroses following minor trauma and a maternal uncle with a severe bleeding disorderProlonged aPTT, normal PT, normal platelet count, and normal bleeding time
  • A 22-year-old woman presenting with prolonged epistaxis, easy bruising, and a history of heavy menstrual bleeding since menarcheProlonged aPTT, normal PT, normal platelet count, and prolonged bleeding time
  • A 65-year-old man in the intensive care unit with gram-negative bacteremia who develops diffuse oozing from venipuncture sitesProlonged aPTT, prolonged PT, decreased platelet count, and decreased fibrinogen
  • A 58-year-old man taking chronic medication for a mechanical aortic valve who presents with a large, spontaneous flank hematomaProlonged PT, normal or mildly prolonged aPTT, normal platelet count, and normal bleeding time

Cevap

Hemophilia matches with isolated prolonged aPTT. von Willebrand disease matches with prolonged aPTT and prolonged bleeding time. Disseminated intravascular coagulation matches with globally prolonged coagulation times and consumptive markers (decreased platelets and fibrinogen). Vitamin K antagonism matches with isolated prolonged PT.
Each underlying clinical condition produces a distinct and predictable pattern of laboratory abnormalities based on the specific phase of hemostasis that is disrupted.

Adım Adım Çözüm

1
Analyze the first clinical vignette (14-year-old boy).
Identify a sex-linked bleeding disorder affecting deep tissues (hemarthrosis), indicating Hemophilia.
Hemophilia A and B are intrinsic pathway factor deficiencies that manifest with deep tissue and joint bleeding.
2
Determine the laboratory profile for Hemophilia.
Matches with prolonged aPTT, normal PT, and normal bleeding time.
Deficiencies in factors VIII or IX specifically prolong the intrinsic pathway measurement (aPTT) without affecting primary platelet plug formation.
3
Analyze the second clinical vignette (22-year-old woman).
Identify a mucosal bleeding pattern (menorrhagia, epistaxis), indicating von Willebrand disease.
von Willebrand disease affects primary hemostasis and factor VIII stabilization.
4
Determine the laboratory profile for von Willebrand disease.
Matches with prolonged bleeding time and prolonged aPTT, with normal PT.
Impaired platelet adhesion prolongs bleeding time, and reduced factor VIII prolongs aPTT.
5
Analyze the third clinical vignette (ICU patient with bacteremia).
Identify a consumptive coagulopathy indicative of disseminated intravascular coagulation (DIC).
Sepsis triggers systemic, uncontrolled coagulation activation.
6
Determine the laboratory profile for disseminated intravascular coagulation.
Matches with prolonged PT, prolonged aPTT, decreased platelet count, and decreased fibrinogen.
Systemic consumption universally depletes all coagulation factors, fibrinogen, and platelets.
7
Analyze the fourth clinical vignette (patient with mechanical valve).
Identify the use of a vitamin K antagonist (warfarin) causing supratherapeutic bleeding.
Patients with mechanical valves require chronic anticoagulation, typically managed with warfarin.
8
Determine the laboratory profile for vitamin K antagonism.
Matches with prolonged PT, normal or mildly prolonged aPTT, and normal bleeding time.
Warfarin rapidly depletes factor VII, markedly prolonging the extrinsic pathway measurement (PT).

Anahtar Kavram

Differentiation of coagulation disorders requires analyzing both the coagulation cascade (PT and aPTT) and primary hemostasis mechanisms (platelet count and bleeding time).
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Konular

Hematology and Oncology

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