Practice questions answers coagulopathy
Practice questions answers
Coagulopathy
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Jun Wang, MD, PhD
2. B. Factor VIII is low in patients with von Willebrand disease, since von Willebrand factors are carriers of factor VIII. Lacking of von Willebrand factors will influence stabilization of factor VIII. This is less likely to be either Hemophilia A or Hemophilia B since the later two likely to have severe bleeding episodes, such as hemarthrosis since birth. Factor IX levels are usually normal in von Willebrand disease. Deficiency of factor VII is usually associated with prolonged PT and normal PTT. Presence of factor VIII antibodies is unlikely due to correction of PTT by mixing studies. Platelet GPIIb/IIIa is more commonly seen in chronic immune thrombocytopenic purpura.
3. E. With the low levels of von Willebrand factor and factor VIII, this is most likely von Willebrand disease. Hemolytic-uremic syndrome and atypical hemolytic-uremic syndrome usually have thrombocytopenia, anemia and fragmented red cells (schistocytosis). Hemophilia A and Hemophilia B have factor VIII and factor IX deficiency, but von Willebrand factors are usually normal.
4. D. Von Willebrand factors mediates initial adhesion of platelets to vascular collagens. Common coagulation pathway abnormalities have prolonged prolonged PT and PTT.
5. C. This is most likely hemarthrosis due to either hemophilia A or hemophilia B. Factor V or X deficiency usually have prolonged prolonged PT and PTT. Deficiency of factor VII is usually associated with prolonged PT and normal PTT. Von Willebrand disease usually have mild bleeding disorder.
6. C. Intact knee stability tests are unlikely seen in ligament injuries. Bacterial arthritis usually has fever, leukocytosis and left shift, but not abnormal coagulation tests. Synovial inflammation usually do not influence coagulation tests.
7. B. This is most likely a congenital hemophilia A. Inhibitor of factor VIII, as seen in acquired hemophilia, usually presents in older population. Bacterial arthritis usually has fever, leukocytosis and left shift, but not abnormal coagulation tests. Platelet antibodies are usually seen in acute immune thrombocytopenic purpura and chronic immune thrombocytopenic purpura. Ultra large von Willebrand multimers are seen thrombotic thrombocytopenic purpura.
8. C. See discussion for question 5.
9. B. Normal PT and prolonged PTT is most compatible with intrinsic coagutation pathway factor deficiency. This patient has a history of autoimmune disorder (Grave’s disease), this is likely an acquired hemophilia, most commonly, factor VIII inhibitor. Deficiency of factor VII is usually associated with prolonged PT and normal PTT. Von Willebrand disease usually have mild bleeding disorder. Vitamin K deficiency, including warfarin associated coagulopathy deficiency usually have normal PTT and prolonged PT, due to factor VII deficiency. Uterine neoplasms, including leiomyomas, may cause abnormal uterine bleeding. However, the coagulation tests are usually normal.
10. A. See discussion of question 9. Overconsumption of coagulation factors can be seen in disseminated intravascular coagulation, a condition both PT, PTT will be prolonged, platelets and fibrinogen tends to be reduced.
11. A. See discussion of question 9. Liver disease associated coagulopathy usually have prolonged PT and PTT.
12. B. Factor IX deficiency is seen in hemophilia B. Hemophilia A has factor VIII deficiency. Chronic immune thrombocytopenic purpura and acute immune thrombocytopenic purpura have normal PT and PTT, as well as thrombocytopenia. Lupus coagulopathy is a type of acquired hemophilia, usually with a clinical history of autoimmune disorder, tumors, hepatitis, or drug usage, etc. Vitamin K deficiency, including warfarin associated coagulopathy deficiency usually have normal PTT and prolonged PT, due to factor VII deficiency.
13. B. This is most likely a hemophilic hemarthrosis. Factor VIII deficiency is seen in hemophilia A. Factor IX deficiency is seen in hemophilia B. Vitamin K deficiency, including warfarin associated coagulopathy deficiency usually have normal PTT and prolonged PT, due to factor VII deficiency. Von Willebrand disease usually have mild bleeding disorder, and hemarthrosis is uncommon. Acquired hemophilia, usually has clinical history of autoimmune disorder, tumors, hepatitis, or drug usage, etc.
14. D. Both hemophilia A and hemophilia B are X-linked recessive disorders, and predominantly occur in male. Hemophilic females are usually associated with high degree of X-inactivation, Turner syndrome or homozygosity from a hemophilic father and carrier mother. This patient has other features of Turner syndrome including short statue and underdeveloped breast. Other autoimmune disorders should have relevant presentations. Vitamin K deficiency, including warfarin associated coagulopathy usually have normal PTT and prolonged PT, due to factor VII deficiency. Liver disease associated coagulopathy usually have prolonged PT and PTT.
15. E. Prolonged PT and PTT that can be corrected by mixing studies are compatible with multiple factor deficiency, as seen in severe vitamin K deficiency, including warfarin associated coagulopathy. He has history of using rodenticides, making it likely to be rodenticide toxicity. Exaggerated hypertension, urinary tract neoplasm/infections may cause hematuria due to impaired renal function or local irritation, not coagulopathy. Liver disease associated coagulopathy usually have prolonged PT and PTT, history of heavy alcohol drinking, and associated physical examination findings of abnormal liver function.
16. B. Warfarin inhibits vitamin K reductase to reduce recycling of oxidized vitamin K. Reduced vitamin K is need for vitamin K dependent carboxylase in posttranslation modification of coagulation factors including II, VII, IX and X. Correction of PT or PTT by mixing studies is not compatible with factor inhibitors. Malabsorption of fat may cause vitamin K deficiency, but usually presents with associated symptoms, such as light-colored foul-smelling bulky stools and steatorrhea, etc. Overconsumption of coagulation factors can be seen in disseminated intravascular coagulation, a condition both PT, PTT will be prolonged, platelets and fibrinogen tends to be reduced.
17. B. His history and liver function tests are consistent with abnormal liver function, as well prolonged PT and PTT, supporting the diagnosis of liver disease associated coagulopathy. Acute bronchopneumonitis usually accompanies with fever, leukocytosis and left shift. Metastatic prostate cancer usually causes elevated PSA. Trauma and tumors usually will not affect coagulation factors unless disseminated intravascular coagulation developed, when fibrinogen and FDP will be abnormal.
18. B. Liver disease associated coagulopathy has reduced levels of coagulation factors that are synthesized in liver, except factor VIII (produced in endothelium) and factor XIII (produced in bone marrow). Presence of inhibitor is unlikely due to negative mixing studies. Ultra large von Willebrand multimers are seen in thrombotic thrombocytopenic purpura.
19. E. Reduced levels of platelet and coagulation factors and elevated levels of FDP are most suggestive of disseminated intravascular coagulation, a condition of widespread activation of coagulation cascades due to tissue factor release. Platelet activation by ultra large von Willebrand multimers, endothelial injury, and autoantibodies can be seen in thrombotic thrombocytopenic purpura, hemolytic-uremic syndrome and atypical hemolytic-uremic syndrome and heparin induced thrombocytopenia, respectively. Vitamin K deficiency, including warfarin associated coagulopathy usually have normal platelet, PTT and prolonged PT, due to factor VII deficiency.
20. A. Presence of Fagot cells and positive finding of t(15;17) is diagnostic for APL with PML-RARA. APL patients has a higher risk of developing disseminated intravascular coagulation, before or after chemotherapy.
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