Megaloblastic anemia




Megaloblastic anemia

Hematological system


Iron deficiency anemia



Sideroblastic anemia

Anemia of chronic disease

Lead poisoning

Hemolytic disease of the newborn

Glucose-6-phosphate dehydrogenase (G6PD) deficiency

Autoimmune hemolytic anemia

Pyruvate kinase deficiency

Paroxysmal nocturnal hemoglobinuria

Sickle cell disease (NORD)

Hereditary spherocytosis

Anemia of chronic disease

Aplastic anemia

Fanconi anemia

Megaloblastic anemia

Folate (Vitamin B9) deficiency

Vitamin B12 deficiency

Fanconi anemia

Diamond-Blackfan anemia

Heme synthesis disorders

Acute intermittent porphyria

Porphyria cutanea tarda

Lead poisoning

Coagulation disorders


Vitamin K deficiency

Platelet disorders

Bernard-Soulier syndrome

Glanzmann's thrombasthenia

Hemolytic-uremic syndrome

Immune thrombocytopenic purpura

Thrombotic thrombocytopenic purpura

Mixed platelet and coagulation disorders

Von Willebrand disease

Disseminated intravascular coagulation

Heparin-induced thrombocytopenia

Thrombosis syndromes (hypercoagulability)

Antithrombin III deficiency

Factor V Leiden

Protein C deficiency

Protein S deficiency

Antiphospholipid syndrome


Hodgkin lymphoma

Non-Hodgkin lymphoma


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Langerhans cell histiocytosis

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Plasma cell dyscrasias

Multiple myeloma

Monoclonal gammopathy of undetermined significance

Waldenstrom macroglobulinemia

Hematological system pathology review

Microcytic anemia: Pathology review

Non-hemolytic normocytic anemia: Pathology review

Intrinsic hemolytic normocytic anemia: Pathology review

Extrinsic hemolytic normocytic anemia: Pathology review

Macrocytic anemia: Pathology review

Heme synthesis disorders: Pathology review

Coagulation disorders: Pathology review

Platelet disorders: Pathology review

Mixed platelet and coagulation disorders: Pathology review

Thrombosis syndromes (hypercoagulability): Pathology review

Lymphomas: Pathology review

Leukemias: Pathology review

Plasma cell disorders: Pathology review

Myeloproliferative disorders: Pathology review


Megaloblastic anemia


0 / 27 complete

USMLE® Step 1 questions

0 / 3 complete

High Yield Notes

4 pages


Megaloblastic anemia

of complete


USMLE® Step 1 style questions USMLE

of complete

A 35-year-old woman presents to her provider’s office for evaluation of fatigue and exercise intolerance that began two months ago. Past medical history is notable for Crohn disease diagnosed eight-years ago. She is taking mesalamine but reports frequent “flare-ups.” The patient consumes 3-4 glasses of wine per week. Her temperature is 36.9°C (98.4°F), blood pressure is 123/76 mmHg, pulse is 75/min, and respiratory rate is 12/min. The patient has conjunctival pallor. Cardiac, pulmonary, and abdominal examinations are non-contributory. Neurological examination reveals decreased proprioception and vibratory sensation in the lower extremities. Complete blood count reveals a hemoglobin of 8.8 g/dL and a mean corpuscular volume (MCV) of 115 µm3. Which of the following findings would be most likely present in this patient?  

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megaloblastic anemia p. 428

Megaloblastic anemia p. 425, 428

cytarabine p. 448

Diphyllobothrium latum p. , 157

as drug reaction p. 251

macro-ovalocytes in p. 423

orotic aciduria p. 428

trimethroprim p. 191

tropical sprue p. 390

vitamin BNaN deficiency p. 66

vitamin BNaN deficiency p. 67

Methotrexate p. 446

megaloblastic anemia p. 251

Neutrophils p. 414

megaloblastic anemia p. 428

nonmegaloblastic anemia p. 428


megaloblastic anemia p. 251

Sulfa drugs p. 253

megaloblastic p. 251


Megaloblastic anemia is a type of anemia caused by deficiencies in folic acid (folate) or vitamin B12. Folic acid and vitamin B12 are essential for DNA synthesis, and thus the production of healthy red blood cells. Megaloblastic anemia is characterized by large, nucleated red blood cell precursors which don't divide and produce more red blood cells as normal precursor cells do. Symptoms include fatigue, shortness of breath, and pale skin.


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