Block 10 RBC MCQ's

The patient's presentation of acute onset normocytic, normochromic anemia, hemoglobinuria, hemosiderinuria, jaundice, and decreased serum haptoglobin is indicative of hemolysis. Hemolysis refers to the breakdown of red blood cells, leading to the release of hemoglobin into the bloodstream. This can result from various causes such as autoimmune disorders, infections, certain medications, or genetic conditions. The presence of hemoglobinuria and hemosiderinuria suggests intravascular hemolysis, where red blood cells are destroyed within the blood vessels. The decreased serum haptoglobin levels further support the diagnosis of hemolysis as haptoglobin binds to free hemoglobin to prevent its loss in the urine.

The laboratory findings of decreased MCV, increased MCHC, and increased osmotic fragility of red blood cells are characteristic of hereditary spherocytosis. In this condition, the red blood cells are spherical in shape instead of the usual biconcave disc shape. This abnormal shape leads to increased fragility and destruction of the red blood cells, resulting in anemia. Therefore, the most likely appearance of the red blood cells on peripheral blood smear would be spherocytes.

The patient's symptoms of a smooth and sore tongue, along with spooning of the fingernails, are consistent with iron deficiency anemia. In iron deficiency anemia, the red blood cells are typically smaller (microcytic) and have a decreased color (hypochromic) due to insufficient iron for hemoglobin production. Therefore, the most likely red blood cell indices would be microcytic and hypochromic.

The most likely diagnosis for this patient is B-Thalassemia Major (Cooley's Anemia). The patient's symptoms and laboratory findings are consistent with severe anemia, which is a characteristic feature of B-Thalassemia Major. The frequent red blood cell transfusions in the past medical history suggest a chronic condition that requires regular transfusions to maintain hemoglobin levels. The jaundice, pallor, and respiratory distress are also common manifestations of severe anemia. The decreased hemoglobin, hematocrit, red blood cell count, MCV, and MCHC are all consistent with B-Thalassemia Major, as these parameters are typically decreased in this condition.

Intravascular hemolysis is associated with the most severe serum haptoglobin depletion. Intravascular hemolysis refers to the breakdown of red blood cells within the blood vessels, leading to the release of hemoglobin. Haptoglobin is a protein that binds to free hemoglobin in the bloodstream, preventing its loss through urine and protecting against oxidative damage. In cases of intravascular hemolysis, there is a significant release of hemoglobin, leading to a rapid depletion of haptoglobin levels. This is in contrast to extravascular hemolysis, where red blood cells are broken down outside of the blood vessels, and haptoglobin is not as severely depleted. Chronic blood loss and acute blood loss do not directly involve the breakdown of red blood cells and are not associated with significant haptoglobin depletion.

The bone marrow shown is most likely taken from a patient with pancytopenia and low reticulocyte count. Pancytopenia refers to a decrease in all three blood cell types (red blood cells, white blood cells, and platelets) and low reticulocyte count indicates decreased production of red blood cells. This suggests a bone marrow disorder or failure, leading to a decrease in all blood cell types.

The most likely diagnosis for this patient is iron deficiency. Iron deficiency is a common cause of anemia in pregnancy, and the patient's symptoms and laboratory findings are consistent with this diagnosis. The decreased red blood cell count, corrected reticulocyte count, MCV, and MCHC are all indicative of iron deficiency anemia. Additionally, the patient's complaint of severe fatigue is a common symptom of iron deficiency.

The signs and symptoms described in the question, including severe lifelong anemia, non-healing leg ulcers, and recurrent episodes of abdominal and chest pain, are most likely associated with sickle cell disease. Increased hemoglobin S on electrophoresis is characteristic of sickle cell disease, which is a genetic disorder that causes red blood cells to become misshapen and leads to various complications, including anemia and tissue damage.

The most likely cause of the woman's anemia is chronic blood loss and iron deficiency anemia. This can be inferred from the information provided, such as the excessive uterine bleeding and the low levels of hemoglobin, hematocrit, and red blood cell count. Chronic blood loss can lead to a decrease in iron stores in the body, resulting in iron deficiency anemia.

The patient's presentation of fever, infection, lymphadenopathy, and splenomegaly, along with the laboratory findings of low serum iron, low serum iron binding capacity, low mean corpuscular hemoglobin concentration, and low mean cell volume, are consistent with the diagnosis of anemia of chronic disease. Anemia of chronic disease is characterized by a chronic inflammatory condition, such as Hodgkin's Lymphoma, which leads to decreased iron availability and impaired erythropoiesis. This type of anemia is typically normocytic and normochromic, as seen in this patient.

Paresthesias in hands and feet are diagnostic signs that distinguish between B12 and folate-deficiency megaloblastic anemia. This symptom refers to abnormal sensations such as tingling, numbness, or a "pins and needles" feeling in the hands and feet. This is a specific manifestation of B12 deficiency and is not typically seen in folate deficiency. Other symptoms like pallor and fatigue, cheilosis/cheilitis, atrophic glossitis, and macroovalocytes and hypersegmented neutrophils in peripheral blood can be present in both B12 and folate deficiency, but paresthesias in hands and feet are more specific to B12 deficiency.

The correct answer is factor X. This is because the mixing studies show that both the PT and PTT are completely corrected, indicating that the patient's prolonged clotting times are due to a deficiency in a coagulation factor rather than an inhibitor. Among the options given, factor X is the most likely factor to be decreased as it plays a crucial role in the common pathway of the coagulation cascade.

The given laboratory results would be most helpful in confirming the diagnosis of thrombocytopenia, which is a condition characterized by a decreased platelet count. The normal PT (prothrombin time) and PTT (partial thromboplastin time) indicate that the patient's coagulation factors are functioning properly. However, the increased bleeding time suggests impaired platelet function, while the decreased platelet count confirms the diagnosis of thrombocytopenia. This combination of findings is consistent with the patient's symptoms of bleeding from the nose and gums with petechiae and purpura.

not-available-via-ai

Patients with anemia of chronic diseases typically have increased ferritin levels due to inflammation and increased iron storage. However, their serum iron levels are decreased as iron is sequestered within macrophages. Additionally, the total iron-binding capacity (TIBC) is decreased because the body's iron stores are already saturated. As a result, the percentage saturation of transferrin, which represents the amount of iron bound to transferrin, is also decreased.

The description of the patient's condition, including low blood pressure and weak but rapid pulse, suggests that the patient is in a state of shock. In cases of shock, the body tries to compensate by constricting blood vessels and increasing heart rate, which can lead to decreased blood volume. This decrease in blood volume would result in a decreased hemoglobin and hematocrit level. The normal MCV (mean corpuscular volume) and MCHC (mean corpuscular hemoglobin concentration) suggest that the size and color of the red blood cells are within normal range, indicating that there is no significant abnormality in the red blood cell morphology.

Pulmonary thromboembolism and cerebral sinus thrombosis are the most dangerous complications in patients with heparin-induced thrombocytopenia. Pulmonary thromboembolism refers to a blockage in the pulmonary artery, which can lead to severe respiratory distress and even death. Cerebral sinus thrombosis is the formation of a blood clot in the veins that drain blood from the brain, which can cause stroke-like symptoms and potentially be fatal. Both of these complications are life-threatening and require immediate medical attention.

The most beneficial test in confirming the diagnosis in this case would be the osmotic fragility test. This test is used to evaluate the fragility of red blood cells and can help diagnose conditions such as hereditary spherocytosis, which is characterized by decreased red blood cell survival and increased osmotic fragility. Given the patient's symptoms of anemia, jaundice, and splenomegaly, hereditary spherocytosis is a likely diagnosis. The osmotic fragility test would help confirm this by demonstrating increased fragility of the red blood cells.

not-available-via-ai

The Direct Coomb's test is the best test to order in this case because the patient's presentation is consistent with autoimmune hemolytic anemia (AIHA), which is characterized by the destruction of red blood cells by autoantibodies. The Direct Coomb's test detects the presence of antibodies bound to the patient's red blood cells, confirming the diagnosis of AIHA. The other options are not specific for AIHA and would not provide the same level of diagnostic information.

The correct answer is "Decreased serum ferritin and depletion of bone marrow iron store." Serum ferritin is a marker of iron stores in the body, and a decrease in serum ferritin levels indicates a depletion of iron stores. This is an early laboratory sign of iron deficiency anemia. Additionally, the depletion of iron stores in the bone marrow further supports the diagnosis of iron deficiency.

The next best step in the evaluation of this patient is a bone marrow biopsy. This is because the patient presents with epistaxis and moderate splenomegaly, which could indicate a hematologic disorder such as aplastic anemia or myelodysplastic syndrome. A bone marrow biopsy can help determine the cause of the decreased platelet count and provide further information for diagnosis and treatment. The other options, such as bleeding time, complete blood count, Ristocetin test, and osmotic fragility test, may not provide enough information to identify the underlying condition.