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Zorluk: Çok zorHematology and Oncology

A hematology consultation service is reviewing the clinical data and coagulation profiles of five distinct adult patients. Based on the patterns of standard coagulation testing (PT, aPTT), mixing studies, and clinical presentation, match each patient's profile to the most accurate underlying diagnosis.

  • Normal PT, normal aPTT, normal platelet count; abnormal clot solubility in 5M urea; presentation of severe delayed wound hemorrhage after minor surgery.Factor XIII deficiency
  • Prolonged PT, normal aPTT; corrects immediately with normal plasma mix; normal platelet count; patient has severe malnutrition and has been on prolonged broad-spectrum antibiotics.Early vitamin K deficiency
  • Prolonged aPTT, normal PT; 1:1 mixing study shows initial correction, but the aPTT prolongs again after 2 hours of incubation at 37°C; patient presents with massive spontaneous gluteal hematoma.Acquired hemophilia A (Factor VIII inhibitor)
  • Prolonged aPTT, normal PT; 1:1 mixing study fails to correct immediately; normal bleeding time; patient has a history of recurrent deep vein thromboses and mid-trimester pregnancy losses.Antiphospholipid syndrome (Lupus anticoagulant)
  • Prolonged PT and aPTT; isolated severe reduction in Factor X activity; patient presents with periorbital purpura, macroglossia, and nephrotic-range proteinuria.Systemic AL amyloidosis

Cevap

Profile 1 matches Factor XIII deficiency; Profile 2 matches Early vitamin K deficiency; Profile 3 matches Acquired hemophilia A; Profile 4 matches Antiphospholipid syndrome; Profile 5 matches Systemic AL amyloidosis.
The correct pairings require synthesis of clinical signs and advanced hematologic testing. Factor XIII deficiency selectively fails the 5M urea clot solubility test because fibrin is not cross-linked, causing delayed bleeding. Early vitamin K deficiency rapidly depletes Factor VII (shortest half-life), prolonging the PT, which corrects on a standard mixing study. Acquired hemophilia A (Factor VIII inhibitor) is classically time- and temperature-dependent, showing initial correction followed by prolongation. Lupus anticoagulant immediately binds phospholipids, causing immediate non-correction of the aPTT without bleeding, instead driving thrombosis. Systemic AL amyloidosis uniquely causes isolated Factor X deficiency due to direct fibril binding, presenting alongside macroglossia and nephropathy.

Adım Adım Çözüm

1
Analyze standard coagulation tests (PT and aPTT) to determine the affected pathways.
Isolated PT prolongation points to the extrinsic pathway; isolated aPTT points to the intrinsic pathway; combined points to the common pathway; entirely normal tests with delayed bleeding suggest structural fibrin cross-linking issues.
Basic coagulation cascade interpretation sets the foundation for diagnosing hemostatic disorders.
2
Evaluate mixing study results for the profiles with prolonged tests.
Immediate correction suggests a simple factor deficiency (e.g., Vitamin K deficiency). Immediate non-correction suggests an immediate inhibitor (Lupus anticoagulant). Time-dependent non-correction suggests a slow-acting inhibitor (Factor VIII autoantibody).
Mixing studies differentiate between missing factors and the presence of acquired neutralizing antibodies or phospholipid inhibitors.
3
Incorporate specific clinical syndromes and unique laboratory phenomena.
The 5M urea test specifically identifies Factor XIII. The triad of macroglossia, periorbital purpura, and nephropathy points to AL amyloidosis, which exhibits unique Factor X binding. Broad-spectrum antibiotics and malnutrition point to Vitamin K depletion.
Advanced diagnosis requires integrating abstract laboratory phenomena with systemic physical exam findings.

Anahtar Kavram

Advanced integration of coagulation cascade abnormalities, mixing studies, and systemic disease associations.
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Hematology and Oncology

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