Anemia Megaloblástica

Summary

This video script discusses megaloblastic anemia, caused by deficiencies in vitamin B12 and folic acid. It highlights characteristics like macrocytosis and multiple nuclear lobes in blood cells. Symptoms include balance issues and proprioception loss. Causes range from veganism to malabsorption due to gastrointestinal diseases. The script also covers diagnostic tests and treatment approaches, emphasizing the importance of B12 and folic acid in preventing neurological changes.

Takeaways

• 🩸 Anemia megaloblastica is characterized by a deficiency in vitamin B12 or folic acid.
• 🔍 Key characteristics in peripheral blood include macrocytosis (large red blood cells) and multiple nuclear lobes.
• 🧬 Patients may exhibit signs like proprioception loss, unsteady gait, and difficulty in balance tests.
• 🥬 Causes of B12 deficiency range from vegan diets to malabsorption issues like pernicious anemia and gastrectomy.
• 🌿 Folic acid deficiency can occur due to poor diet, especially in those not consuming enough green leafy vegetables.
• 🤰 Conditions like pregnancy, hemolytic anemia, and certain diseases can lead to increased requirements for folic acid.
• 💊 Certain medications, chronic alcohol abuse, and intensive care treatments can deplete folic acid levels.
• 🧪 Diagnostic tests for B12 and folic acid deficiency include measuring levels of vitamin B12, homocysteine, and methylmalonic acid in the blood.
• 🩺 Clinical signs of B12 deficiency include neurological changes, which are crucial to identify and treat.
• 📉 A typical B12 deficiency might show levels below 200 pg/mL, with severe deficiency below 100 pg/mL.
• 📈 Folic acid levels below 4 ng/mL indicate a deficiency, with normal levels being above this threshold.

Q & A

What is megaloblastic anemia?

Megaloblastic anemia is a type of anemia caused by a deficiency in vitamin B12 or folic acid, leading to the production of abnormally large, immature red blood cells.

What are the characteristics of red blood cells in megaloblastic anemia?

Red blood cells in megaloblastic anemia are large with a high mean corpuscular volume (MCV), and they may have multiple lobes, which is atypical as normal red blood cells typically have one or two lobes.

What is meant by 'macrocytosis' in the context of megaloblastic anemia?

Macrocytosis refers to the condition where red blood cells are larger than normal, which is a characteristic feature observed in the peripheral blood of patients with megaloblastic anemia.

What are some peripheral blood features of megaloblastic anemia?

Peripheral blood features include the presence of macrocytes, hypersegmented neutrophils, and the presence of megaloblasts, which are immature, large red blood cells.

What is the 'Pappenheimer bodies' mentioned in the script?

Pappenheimer bodies are inclusion bodies found in red blood cells, which can be indicative of iron deficiency or, in the context of this script, megaloblastic anemia.

How can you test for a deficiency in vitamin B12 or folic acid?

Deficiencies can be tested through blood tests that measure the levels of vitamin B12 and folic acid in the blood. High levels of homocysteine and methylmalonic acid (MMA) can also suggest a deficiency.

What are some causes of vitamin B12 deficiency mentioned in the script?

Causes include veganism, pernicious anemia due to a lack of intrinsic factor, gastrectomy, diseases of the ileum such as Crohn's disease, selective congenital malabsorption, and nutritional deficiencies.

Why is vitamin B12 important for neurological function?

Vitamin B12 is crucial for maintaining neurological health as it plays a role in the production of myelin, the protective sheath around nerve fibers, and is involved in the conversion of homocysteine to methionine, an essential amino acid.

What are the symptoms of a deficiency in vitamin B12 or folic acid?

Symptoms can include anemia, neurological problems such as numbness and tingling in the extremities, difficulty maintaining balance, and cognitive issues like memory problems.

What dietary sources are rich in vitamin B12?

Vitamin B12 is primarily found in animal products such as meat, fish, eggs, and dairy. The script also mentions that it is found in 'camisas vermelhas' which could refer to a specific food item rich in B12.

How can megaloblastic anemia be treated?

Treatment typically involves supplementation with vitamin B12 or folic acid, depending on the deficiency. Injections or oral supplements can be used to increase levels of the deficient nutrient.