Internal Medicine
2 questionsThalassemia gives protection against ?
Anemia with reticulocytosis is seen in -
NEET-PG 2013 - Internal Medicine NEET-PG Practice Questions and MCQs
Question 411: Thalassemia gives protection against ?
- A. Protection against filaria
- B. Protection against kala-azar
- C. Protection against leptospirosis
- D. Protection against malaria (Correct Answer)
Explanation: Protection against malaria - Individuals with thalassemia, particularly thalassemia trait, have some degree of protection against severe forms of malaria, specifically Plasmodium falciparum [1]. - The altered red blood cell structure and reduced hemoglobin content in thalassemia make the red blood cells less hospitable for the parasites, hindering their replication and survival [1]. Protection against filaria - Filaria is caused by parasitic worms (nematodes) transmitted by mosquitoes, leading to lymphatic filariasis (elephantiasis) or onchocerciasis (river blindness). - Thalassemia's primary impact is on red blood cell health and oxygen transport, offering no known protective effect against nematode infections or their associated pathology. Protection against kala-azar - Kala-azar (visceral leishmaniasis) is caused by Leishmania parasites transmitted by sandflies, primarily affecting the reticuloendothelial system (spleen, liver, bone marrow). - There is no established scientific evidence indicating that thalassemia provides protection against Leishmania infections or their clinical manifestations. Protection against leptospirosis - Leptospirosis is a bacterial infection caused by Leptospira bacteria, typically acquired through contact with contaminated water or animal urine. - Thalassemia is a genetic blood disorder; its physiological effects are unrelated to the mechanisms of infection or immunity against bacterial pathogens like Leptospira.
Question 412: Anemia with reticulocytosis is seen in -
- A. Hemolysis (Correct Answer)
- B. Iron deficiency anemia
- C. Vitamin B12 deficiency
- D. Aplastic anemia
Explanation: ***Hemolysis*** - Reticulocytosis indicates a compensatory response to anemia, often occurring in hemolytic processes where the **bone marrow increases red blood cell production** in response to red blood cell destruction. - Conditions like **sickle cell disease** or **autoimmune hemolytic anemia** lead to hemolysis, further confirming increased reticulocyte count. *Iron deficiency anemia* - Typically presents with a **low reticulocyte count** as the bone marrow does not have sufficient iron to produce new red blood cells. - This condition is characterized by **microcytic, hypochromic** red blood cells due to inadequate iron stores. *Vitamin B12 deficiency* - Often results in a **macrocytic anemia** with a variable reticulocyte count; however, reticulocytosis is generally not seen initially. - This deficiency affects DNA synthesis, leading to ineffective erythropoiesis and the presence of **megaloblastic changes**. *Aplastic anemia* - Characterized by a **decrease in all types of blood cells** (pancytopenia) and typically has a **low reticulocyte count** due to bone marrow failure. - There is insufficient production of red blood cells, hence **reticulocytosis is not observed**.
Microbiology
1 questionsPersons with heterozygous sickle cell trait are protected from infection by:
NEET-PG 2013 - Microbiology NEET-PG Practice Questions and MCQs
Question 411: Persons with heterozygous sickle cell trait are protected from infection by:
- A. Pneumococcus
- B. P. falciparum (Correct Answer)
- C. P. vivax
- D. Salmonella
Explanation: ***P. falciparum*** - Individuals with heterozygous sickle cell trait have a **protective effect** against severe malaria caused by *P. falciparum* due to altered red blood cell morphology [1][2]. - The sickle hemoglobin (HbAS) provides a **selective advantage**, reducing the severity of malaria infections and the parasitic load [2][3]. *P. vivax* - Sickle cell trait does not confer significant protection against *P. vivax*, which primarily infects non-sickled red blood cells [2]. - The infection still occurs in individuals with the trait because it specifically affects the reticulocyte count, which is less impacted by sickling. *Salmonella* - While sickle cell disease is linked with increased susceptibility to **Salmonella infections**, the sickle cell trait itself does not provide protection against it [2]. - The trait does not influence immunity or susceptibility to bacterial pathogens like *Salmonella*. *Pneumococcus* - Individuals with sickle cell trait still have a normal risk of **invasive pneumococcal disease**, similar to those without the trait [2]. - Protection against *Pneumococcus* primarily relates to vaccination status and not to hemoglobinopathies. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Infectious Diseases, pp. 398-400. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Blood And Bone Marrow Disease, pp. 598-599. [3] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. (Basic Pathology) introduces the student to key general principles of pathology, both as a medical science and as a clinical activity with a vital role in patient care. Part 2 (Disease Mechanisms) provides fundamental knowledge about the cellular and molecular processes involved in diseases, providing the rationale for their treatment. Part 3 (Systematic Pathology) deals in detail with specific diseases, with emphasis on the clinically important aspects., pp. 50-51.
Pathology
7 questionsWhich of the following statements about sickle cell anemia is false?
Which of the following statements is false regarding hereditary spherocytosis?
Intracorpuscular hemolytic anemia is seen in ?
In which condition are Pseudo-Pelger-Huët cells typically seen?
Which is not a feature of paroxysmal nocturnal hemoglobinuria?
Localized Langerhans cell histiocytosis affecting head and neck is?
MALT lymphoma is positive for which of the following markers?
NEET-PG 2013 - Pathology NEET-PG Practice Questions and MCQs
Question 411: Which of the following statements about sickle cell anemia is false?
- A. Sickle cells are present in sickle cell anemia.
- B. Target cells are commonly seen in sickle cell anemia.
- C. Ringed sideroblasts are associated with sickle cell anemia. (Correct Answer)
- D. Howell Jolly bodies can be found in sickle cell anemia.
Explanation: ***Ringed sideroblast*** - **Ringed sideroblasts** are not typically associated with sickle cell anemia; they are indicative of disorders like **sideroblastic anemia**. - In sickle cell anemia, the primary findings include **hemolysis** and ineffective erythropoiesis, not ringed sideroblasts [3]. *Howell jolly bodies* - These bodies are remnants of nuclear material and can be found in individuals with **spleen dysfunction**, which can occur in sickle cell anemia [1]. - They are actually a common finding due to **hyposplenism** or **asplenia** in patients with sickle cell disease [2]. *Sickle cells* - The presence of **sickle-shaped red blood cells** is a hallmark of sickle cell anemia, caused by the mutation in the **beta-globin chain** [3]. - These sickle cells are responsible for the characteristic complications of the disease, such as **vaso-occlusive crises** [1][3]. *Target cells* - Target cells, or **codocytes**, are often seen in disorders like **thalassemia** and liver disease, and can also be present in sickle cell anemia. - They are formed due to an increase in the **surface area to volume ratio** of red blood cells, often secondary to **membrane abnormalities** seen in sickle cell changes [2]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Red Blood Cell and Bleeding Disorders, pp. 644-646. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Diseases Of The Urinary And Male Genital Tracts, pp. 570-571. [3] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Blood And Bone Marrow Disease, pp. 598-599.
Question 412: Which of the following statements is false regarding hereditary spherocytosis?
- A. Defect in ankyrin
- B. Reticulocytosis
- C. Decreased MCHC (Correct Answer)
- D. Normal to increased MCV
Explanation: ***Decreased MCHC*** - Hereditary spherocytosis typically presents with an **increased MCHC** due to the spherocytes being more concentrated. - MCHC is a measure of the hemoglobin concentration in red blood cells, and in spherocytosis, this value is often elevated rather than decreased. *Defect in ankyrin* - This is a true statement; hereditary spherocytosis is associated with a defect in **ankyrin**, a protein that helps maintain the cell's membrane structure [2]. - Mutations in ankyrin lead to instability of the red blood cell membrane, resulting in spherocyte formation [2]. *Decreased MCV* - In hereditary spherocytosis, MCV is often **normal or slightly increased**, as it reflects the volume of red blood cells, which can be misinterpreted due to the presence of spherocytes. - Spherocytes are smaller cells, which can mistakenly suggest a falsely decreased MCV if not properly interpreted [1]. *Reticulocytosis* - This condition typically presents with **reticulocytosis** as a response to hemolysis, indicating the bone marrow is producing more red blood cells to compensate [1]. - The presence of reticulocytosis is a common finding in hereditary spherocytosis due to increased destruction of spherocytes. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Blood And Bone Marrow Disease, pp. 597-598. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Red Blood Cell and Bleeding Disorders, pp. 640-641.
Question 413: Intracorpuscular hemolytic anemia is seen in ?
- A. Thalassemia (Correct Answer)
- B. Infection
- C. Thrombotic thrombocytopenic purpura (TTP)
- D. Autoimmune hemolytic anemia
Explanation: ***Thalassemia*** - Thalassemia is characterized by **intracorpuscular hemolysis** due to defective hemoglobin synthesis, leading to premature destruction of red blood cells [1][2]. - It manifests as **microcytic anemia** with associated **extramedullary erythropoiesis** in severe cases [1]. *Autoimmune hemolytic anemia* - This condition leads to **extravascular hemolysis**, primarily affecting red blood cells in the spleen, not within the plasma [2]. - It is often associated with **positive direct Coombs test**, indicating reactants on the RBC surface. *TIP* - TIP (Thrombotic Microangiopathy) primarily involves **microangiopathic hemolytic anemia** and is not classified as intracorpuscular [2]. - The hemolysis in TIP occurs due to **microthrombi**, causing damage to red blood cells as they pass through narrowed vessels. *Infection* - Infections can lead to **hemolysis**, but this is typically **extravascular** due to splenic clearance or due to other mechanisms like **malaria** [2]. - The hemolytic mechanism is not intracorpuscular, as seen in conditions like thalassemia. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Blood And Bone Marrow Disease, pp. 601-602. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Blood And Bone Marrow Disease, pp. 596-597.
Question 414: In which condition are Pseudo-Pelger-Huët cells typically seen?
- A. Hairy cell leukemia
- B. Multiple myeloma
- C. Hodgkin's lymphoma
- D. Myelodysplastic syndrome (Correct Answer)
Explanation: ***Mylodysplastic syndrome*** - Pseudo-Pelger-Huet cells are characteristic and often observed in myelodysplastic syndromes, indicating an ineffective hematopoiesis [1]. - These cells appear as **hyposegmented neutrophils** and are associated with dysplastic changes in the bone marrow [1]. *Hairy cell leukemia* - Typically presents with **hairy cells** in peripheral blood and often involves splenomegaly; pseudo-Pelger-Huet cells are not usual in this condition. - Associated with **PANCYTOPENIA** and reticulin fibrosis, differing from myelodysplastic syndrome. *Hodgkin's lymphoma* - Characterized by the presence of **Reed-Sternberg cells** and typically involves lymphadenopathy. - Peripheral blood findings generally do not include pseudo-Pelger-Huet cells; the focus is on lymphatic tissue. *Multiple myeloma* - Commonly presents with **plasma cells** and related symptoms like bone pain and renal failure, not associated with pseudo-Pelger-Huet cells. - It primarily causes an increase in monoclonal proteins rather than dysplastic changes seen in myelodysplastic syndrome. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Blood And Bone Marrow Disease, pp. 613-614.
Question 415: Which is not a feature of paroxysmal nocturnal hemoglobinuria?
- A. Thrombocytopenia
- B. Hemolysis
- C. Increased LAP score (Correct Answer)
- D. Thrombosis
Explanation: ***Increased LAP score*** - In paroxysmal nocturnal hemoglobinuria, the **LAP score** is typically **low** due to ineffective hematopoiesis and not elevated. - The presence of a low LAP score is inconsistent with the features of this condition, making it the correct choice. *Thrombosis* - Paroxysmal nocturnal hemoglobinuria is **associated with a high risk of thrombosis**, particularly in the **venous system** [2]. - This is due to **increased platelet activation** and excessive thrombin generation resulting from hemolysis. *Hemolysis* - **Hemolysis** is a hallmark feature of paroxysmal nocturnal hemoglobinuria, where there is **destruction of red blood cells** [2,3]. - Patients often present with signs of hemolytic anemia including **elevated bilirubin** and **low haptoglobin** levels. *Thrombocytopenia* - **Thrombocytopenia** is a common finding in paroxysmal nocturnal hemoglobinuria due to **expanded consumption** of platelets during episodes of hemolysis. - This can lead to an **increased risk of bleeding** in affected patients. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Blood And Bone Marrow Disease, pp. 601-602. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Red Blood Cell and Bleeding Disorders, pp. 650-651.
Question 416: Localized Langerhans cell histiocytosis affecting head and neck is?
- A. Eosinophilic granuloma (Correct Answer)
- B. Letterer-siwe disease
- C. Pulmonary Langerhans cell histiocytosis
- D. Hand-Schuller-Christian disease
Explanation: ***Eosinophilic granuloma*** - This is a localized form of **Langerhans cell histiocytosis** that typically presents in the head and neck region, often affecting areas like the skull and mandible [1]. - Characterized by **bone lesions** and may present with **pain or swelling** in the affected area, making it a prominent form in children and young adults. *Pulmonary langerhans cell histiocytosis* - Primarily affects the **lungs** and is associated with **cough, dyspnea**, and pulmonary nodules, not the head and neck region. - Occurs predominantly in **smokers** and involves interstitial lung disease patterns on imaging studies. *Hand-schuller-christian disease* - This condition is a systemic form of Langerhans cell histiocytosis that affects multiple systems rather than being localized, commonly presenting with **diabetes insipidus** and bone lesions. - It is often associated with **exophthalmos** and may involve lymphadenopathy, affecting older children and adults, not localized head and neck involvement. *Letterer-siwe disease* - This represents the acute, disseminated form of Langerhans cell histiocytosis, affecting infants, and is marked by systemic symptoms like **fever**, **rash**, and **hepatosplenomegaly** [1]. - Typically presents with serious manifestations and not specifically localized in the **head and neck area** as seen in eosinophilic granuloma. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of White Blood Cells, Lymph Nodes, Spleen, and Thymus, p. 630.
Question 417: MALT lymphoma is positive for which of the following markers?
- A. CD20 (Correct Answer)
- B. CD19
- C. CD43
- D. CD5
Explanation: ***CD20*** - MALT lymphoma is a type of **B-cell non-Hodgkin lymphoma**, and CD20 is a **pan B-cell marker consistently expressed** in MALT lymphomas. - CD20 positivity is **crucial for diagnosis** and is the **primary therapeutic target** for anti-CD20 monoclonal antibody therapy (Rituximab). - In diagnostic practice, **CD20 is the most important B-cell marker** for identifying MALT lymphoma and guiding treatment decisions. *CD19* - CD19 is also a **pan B-cell marker** and is **typically positive in MALT lymphoma** along with CD20. - However, in the context of this question, **CD20 is the preferred answer** because it is the **standard diagnostic marker emphasized in clinical practice** and the **primary therapeutic target**. - Both markers are positive, but CD20 has greater **clinical and therapeutic significance** in MALT lymphoma management. *CD43* - CD43 is primarily a **T-cell and myeloid marker**, but can show **aberrant expression in 40-50% of MALT lymphomas**. - While it may be positive in some cases, it is **not a defining B-cell lineage marker** and is not used as a primary diagnostic criterion for MALT lymphoma. - Its variable expression makes it **less reliable** than consistent B-cell markers like CD20. *CD5* - CD5 is typically associated with **T-cells** and certain B-cell lymphomas, particularly **chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL)** and **mantle cell lymphoma**. - **MALT lymphoma is characteristically CD5-negative**, which is an important feature for **differentiating it from CD5+ B-cell lymphomas**.