• (A) Endothelium
• (B) Stasis of blood flow
• (C) Platelets
• (D) Coagulation factors

Check AnswerSolution[B]:-Stasis of blood flow

• (A) During maturation megakaryocytes undergoes endomitotic nuclear division
• (B) Thrombopoietin is mainly produced by liver
• (C) Lifespan of platelets is 7-10 days
• (D) They extrude their nucleus before forming mature platelets

Check AnswerSolution[D]:-They extrude their nucleus before forming mature platelets Endomitosis is the characteristic feature of megakaryocyte development in which the DNA is repeatedly replicated in absence of nuclear or cytoplasmic division. Megakaryocyte is the cell where endomitosis begins.Thrombopoietin being the primary regulator of megakarocyte maturation is mainly produced by liver, though some amount is also produced by kidney, marrow stroma and skeletal muscle. The circulatory life span of platelet is approximately 10 days with normal platelet count, but shorter in patients with moderate (7 days) to severe (5 days) thrombocytopenia.Mature platelets are formed as proplatelet from megakaryocytes. Nucleus is not extruded from megakaryocyte.

• (A) ITP
• (B) HSP
• (C) Acute meningococcemia
• (D) Polyarteritis nodosa

Check AnswerSolution[A]:-The increment in platelet count depends on many factors but if all other factors are absent then 1 unit of whole blood derived random platelet increases the platelet count by 5,000/mm3 per square metre. So in a person of BSA 2 m2 it should raise by 10000/mm3 and of 1.5 m2 by 7500/ mm3 respectively.

• (A) 5000
• (B) 10000
• (C) 15000
• (D) 20000

Check AnswerSolution[A]:-5000

• (A) ELISA
• (B) Serotonin release assay
• (C) Prolonged PT/APTT
• (D) Prothrombin fragment 1.2 level

Check AnswerSolution[B]:-Serotonin release assay

• (A) Aplastic anemia
• (B) ITP
• (C) TTP
• (D) Drug induced

Check AnswerSolution[B]:-ITP is the most common cause of acquired severe thrombocytopenia and 50% of ITP cases are children, i.e. < 10 years of age.

• (A) PT is prolonged
• (B) APTT is prolonged
• (C) Both PT and APTT are prolonged
• (D) Both PT and APTT are normal

Check AnswerSolution[D]:-In TTP PT/APTT and fibrinogen levels are usually normal or only mild perturbed. Mild elevations in fibrin degradation products occur in 50% of patients.

• (A) EDTA
• (B) Presence of giant platelets
• (C) Multiple myeloma
• (D) Heparin

Check AnswerSolution[D]:-Pseudothrombocytopenia has been reported in association with the use of EDTA as an anticoagulant, with platelet cold agglutinins associated with multiple myeloma, platelet satellitism, giant platelets and platelet agglutination. Other anticoagulants such as sodium citrate, oxalate, acid citrate dextrose and heparin can also cause platelet agglutination but is less frequent.

• (A) IVIg
• (B) Anti-D
• (C) Rituximab
• (D) Steroids

Check AnswerSolution[C]:-anti-D and steroids are the first line treatment options given in ITP. Rituximab is usually given in cases of chronic ITP who fail to steroids.

• (A) It is most commonly due to anti HPA-1a antibodies
• (B) Usually develops after 3 weeks of blood transfusion
• (C) The treatment of choice is IVIg
• (D) Even HLA matched platelets are not useful

Check AnswerSolution[B]:-The typical patient is a multiparous, middle aged or elderly female who presents with the acute onset of bleeding due to severe thrombocytopenia, a mean of 6-8 days (range 1-14 days) after receiving a blood product containing platelet material. Sera of more than 90% of patients contain antibodies to HPA-1a which is expressed on 97-98% of Caucasians. Bleeding usually lasts for 10 days, but can persist for 60-120 days with fatality rates of 10%. The treatment of choice is IVIg 1g/kg/day � 2 days.More than 90% of patients respond within 2-3 days. HLA matched platelets are generally not useful.

• (A) Low platelet count
• (B) Giant platelets
• (C) Aggregation with ristocetin
• (D) Has defect in GPIb/IX

Check AnswerSolution[C]:-Thrombocytopenia is present in nearly all patients and ranges from 20,000 to near-normal levels. Platelets are large and small. The hallmark of BSS is the failure of platelets to aggregate in response to ristocetin or botrocetin. BSS platelets are deficient in GPIb, GPIX and GPV.

• (A) Autoimmunity
• (B) Hypersplenism
• (C) Bleeding
• (D) Platelet aggregates (microangiopathy)

Check AnswerSolution[D]:-Approximately 1/3rd of patients have symptoms of hemolytic anemia (due to microangiopathic hemolytic anemia). Hemolysis is indicated Platelets and Hemostasis by an elevated reticulocyte count, serum LDH and decreased serum haptoglobin. DCT is almost always negative.

• (A) It cross links platelet to each other
• (B) It is functional in large multimeric form
• (C) Plasma VWF is derived from platelets
• (D) It carries factor IX

Check AnswerSolution[B]:-VWF attaches platelets to the endothelium and vessel walls and not the platelets to each other. The most potent form of VWF is the large multimeric form. The Endothelium secretes VWF by one of the two pathways. The constitutive pathway-directly coupled to VWF synthesis and occurs without stimulation and the regulated pathway-involving VWF stored in Weibel-Palade bodies, is initiated by the action of secretagogues. VWF secreted by the constitutive pathway is in the largest multimeric form. The constitutive secretion of VWF from endothelium maintains the Plasma VWF level. During activation after tissue injury, it is released from the Weibel-Palade bodies of and ?-granules of platelet. VWF carries factor VIII and not IX.

• (A) Ecto-ADPase
• (B) Prostacyclins
• (C) Nitric oxide
• (D) ADP

Check AnswerSolution[D]:-The inhibitory pathways in platelets are CD39 (Ecto-ADPase), nitric oxide and PGE2 (at high concentrations) and PGI2 also called prostacyclins (at low concentrations)

• (A) Thrombin
• (B) Serotonin
• (C) Thromboxane A2
• (D) Epinephrine

Check AnswerSolution[A]:-Thrombin

• (A) Coagulation is started by the interaction of tissue factor with factor VIIa
• (B) Factor VIIa/TF complex activates IX and X Platelets and Hemostasis 5
• (C) Tissue factor is expressed on endothelial cell
• (D) Small amount of factor VII circulates in activated form but is inactive unless bound to tissue factor

Check AnswerSolution[C]:-Tissue factor is expressed on endothelial cell

• (A) Amniotic fluid embolism
• (B) Snake bite
• (C) Abruptio placentae
• (D) Major orthopedic surgery

Check AnswerSolution[D]:-Major orthopedic surgery

• (A) Prolonged PT/APTT
• (B) Thrombocytopenia with schistocytes in peripheral blood
• (C) High levels of FDP/D-dimer
• (D) Increased fibrinogen levels

Check AnswerSolution[D]:-Fibriongen levels are actually decreased and not increased in DIC.

• (A) Platelet aggregation
• (B) Platelet satellitism
• (C) Presence of giant platelets
• (D) Hyper gammaglobulimenia

Check AnswerSolution[D]:-Pseudothrombocytopenia is seen with giant platelets (macrothrombocytopenia) which is seen most commonly in West Bengal, India. In about 1% of individuals, EDTA causes platelet clumping, resulting in pseudothrombocytopenia. Occasionally platelets may be seen adhering to neutrophils (platelet satellitism). Presence of platelet cold agglutinins is seen with multiple myeloma. GP IIb/IIIa antagonists (e.g. abciximab) is associated with both pseudothrombocytopenia and true thrombocytopenia. Antiphospholipid antibodies are also associated with pseudothrombocytopenia.

• (A) Bernard-Soulier syndrome
• (B) Gray-platelet syndrome
• (C) May-Hegglin anomaly
• (D) Wiskott-Aldrich syndrome

Check AnswerSolution[D]:-May-Hegglin anomaly, Fechtner syndrome, Sebastian syndrome and Epstein syndrome are autosomal dominant macrothrombocytopenia with mutations in the MYH9 gene. Wiskott – Aldrich Syndrome is a rare X-linked immunodeficiency disorder characterized by microthrombocytopenia, eczema, recurrent infections, T-cell deficiency and increased risk for autoimmune and lympho proliferative disorders. Platelets appear larger than normal, pale ghost like, oval forms on blood smear in Gray-platelet syndrome. Thrombocytopenia is common and can be moderately severe. In Bernard-Soulier syndrome, thrombocytopenia is present in nearly all patients, but is variable in its severity, ranging from approximately 20,000/ mm3 to normal levels.