Advanced Pathophysiology Exam 2026: Comprehensive Questions with Rationales for Exam Success

A patient with ITP is being treated with corticosteroids. What is the primary reason for this treatment? a) Increase platelet production in bone marrow b) Reduce immune-mediated platelet destruction c) Stimulate spleen activity d) Promote fibrin clot formation Rationale: Corticosteroids suppress the immune system and reduce destruction of platelets by macrophages in the spleen. They do not increase bone marrow production or help clot formation directly. Which finding is most characteristic of Disseminated Intravascular Coagulation (DIC)? a) Isolated thrombocytopenia b) Widespread clotting with consumption of coagulation factors c) Elevated platelet count d) Normal PT and aPTT Rationale: DIC involves excessive clot formation followed by depletion of clotting factors and platelets, causing bleeding. PT and PTT are prolonged, not normal. Which condition involves IgG antibodies against platelets leading to their destruction? a) Hemophilia B b) Immune Thrombocytopenic Purpura (ITP) c) Von Willebrand Disease d) Thrombocythemia Rationale: ITP is caused by IgG antibodies against platelets. Hemophilia is factor deficiency, vWD affects clotting adhesion, thrombocythemia causes too many platelets. Why is splenectomy considered in chronic ITP? a) To increase platelet synthesis b) To treat bone marrow failure c) To remove the primary site of platelet destruction d) To stimulate clotting factor production Rationale: The spleen destroys antibody-coated platelets in ITP; removing it reduces platelet destruction. Bone marrow is not the primary issue. Which dermatologic condition is caused by excessive collagen deposition in the skin? a) Eczema b) Psoriasis c) Keloid formation d) Contact dermatitis Rationale: Keloids result from excessive collagen leading to raised, thickened scars. Eczema and dermatitis are inflammatory; psoriasis is hyperproliferative. What is the main function of von Willebrand factor in coagulation? a) Stimulates platelet production b) Converts fibrinogen to fibrin c) Mediates platelet adhesion to damaged endothelium d) Activates factor II Rationale: vWF helps platelets adhere to vessel walls and carries factor VIII. It does not convert fibrinogen or produce platelets. A patient presents with target lesions on the skin after a herpes simplex infection. What is the likely diagnosis? a) Urticaria b) Erythema multiforme c) Rosacea d) Seborrheic dermatitis Rationale: Erythema multiforme is often triggered by infections like HSV and presents with target lesions. Urticaria is transient wheals, not target-like. Which lab result is expected in essential thrombocythemia? a) Low platelet count b) Platelet count >600,000/mm³ c) Decreased bone marrow cellularity d) Decreased megakaryocyte count Rationale: Essential thrombocythemia is a myeloproliferative disorder causing high platelet counts and increased megakaryocytes, not low ones. Which hematologic condition is associated with Heinz bodies and hemolysis during oxidative stress? a) Iron deficiency anemia b) G6PD deficiency c) Aplastic anemia d) Sickle cell anemia Rationale: G6PD deficiency leads to oxidative damage in RBCs causing Heinz bodies and hemolysis. Iron deficiency has microcytic cells; sickle cell shows sickling. What skin change results from hyperplasia of the epidermis and retention of scales? a) Psoriasis plaques b) Vitiligo c) Urticaria d) Erythema nodosum Rationale: Psoriasis involves epidermal hyperproliferation, leading to thick plaques with silvery scales. Vitiligo causes depigmentation, and urticaria causes hives. Which clotting factor is deficient in Hemophilia A? a) Factor IX b) Factor VIII c) Factor V d) Factor X Rationale: Hemophilia A is caused by a deficiency of factor VIII. Factor IX deficiency is Hemophilia B, and factors V and X are not related to hemophilia. A patient presents with petechiae, prolonged bleeding time, and normal PT/PTT. What is the most likely diagnosis? a) Vitamin K deficiency b) Hemophilia c) Immune thrombocytopenic purpura (ITP) d) DIC Rationale: ITP features low platelets causing mucocutaneous bleeding with normal coagulation times. Hemophilia affects PTT, vitamin K deficiency affects PT, and DIC causes prolonged PT and PTT. Which skin disorder is associated with the Auspitz sign (bleeding when scales are removed)? a) Contact dermatitis b) Psoriasis c) Eczema d) Tinea corporis Rationale: Psoriasis shows pinpoint bleeding beneath plaques when scraped. Eczema and contact dermatitis are inflammatory without this sign; tinea is fungal. Which type of hypersensitivity reaction is involved in allergic contact dermatitis? a) Type I b) Type II c) Type IV d) Type III Rationale: Contact dermatitis is a T-cell mediated delayed hypersensitivity (Type IV). Type I is IgE-mediated, Type II is cytotoxic, and Type III is immune complex-mediated. What is the primary hematologic finding in Thrombotic Thrombocytopenic Purpura (TTP)? a) Elevated platelet count b) Elevated hemoglobin c) Microangiopathic hemolytic anemia with thrombocytopenia d) Leukocytosis Rationale: TTP involves RBC fragmentation and low platelets due to small-vessel clotting. Hemoglobin is low, platelets are low, WBC is usually normal. Which condition is characterized by painless, shallow oral ulcers and target-like skin lesions? a) Urticaria b) Erythema multiforme c) Psoriasis d) Scleroderma Rationale: Erythema multiforme presents with target lesions and mucosal involvement. Urticaria is transient wheals, psoriasis is plaque-forming, scleroderma thickens skin. What lab value is most commonly increased in polycythemia vera? a) Platelets only b) White blood cells only c) Red blood cell mass and hematocrit d) Reticulocyte count only Rationale: Polycythemia vera shows elevated RBCs leading to high hematocrit. Platelets and WBCs may also be high, but RBC increase is most significant. Which of the following is the first-line treatment for acute Thrombotic Thrombocytopenic Purpura (TTP)? a) Corticosteroids b) Splenectomy c) Plasma exchange (plasmapheresis) d) Platelet transfusion Rationale: Plasma exchange removes autoantibodies against ADAMTS13 and replenishes enzymes. Platelet transfusions are avoided as they worsen thrombosis. Which clinical finding is most suggestive of hemolytic disease of the newborn (HDN)? a) Thrombocytopenia with petechiae b) Jaundice and anemia shortly after birth c) Hyperglycemia d) Delayed umbilical cord separation Rationale: HDN presents with jaundice due to hemolysis and anemia. It is not associated with hyperglycemia or immune deficiency.