Question

Please type or submit a PDF document so that I am able to legibly understand the answer. ( This is ome question

2. In the case study below you will explore the causes of B12 deficiency in three patients.

A. Patient A is a college student who has become increasingly tired over the last six months. She thought it was because of her tough schedule but since she noticed tingling in her feet, she thought she should see a doctor. Patient A also has hyperparathyroidism, an autoimmune disorder that affects 100,000 people in the U.S. every year. She is not a vegetarian and eats milk, eggs and meat - all great sources of B12. The doctor ran some blood work and found very low levels of B12. The patient also had parietal cell antibodies present in her blood.

• What do you think is the cause of her B12 deficiency? Why is her body not able to absorb the necessary B12?

• What is the treatment and prognosis for this patient?

• B. **** Patient B had gastric bypass surgery three years ago. He is a vegetarian and sees a nutritionist who ensures his diet is adequate to meet his nutritional needs. Despite this, on a recent trip to his doctor, his blood work showed declining levels of vitamin B12.

• Why does this patient have low B12 even though his diet should be providing enough?

• Why didn’t Patient B have low B12 until three years after surgery?

• C. **** Patient C suffers from Crohn’s disease and had a 60 cm terminal ileal resection 4 months ago.

• What is a terminal ileal resection?

• What is Crohn’s disease and what complication led to the need for an ileal resection?

• What is absorbed by the ileum?

• Will amino acid and glucose uptake be affected by the ileal resection? Explain.

• What is the treatment and prognosis for this patient to ensure she receives necessary nutrition?

Answer 1

First lets be clear with the absorption of vit b12 in our diet . Vitamin b12 is mostly found in meat , eggs etc , so food rich in vitb12 when reaches stomach is digested and vit b12 is seggregated from food. This vit b12 then joins with intrinsic factor (IF) in the duodenum. IF is produced by parietal cells in the stomach . This IF and vitb12 complex then reaches ileum , this complex then binds with the ileal receptors and is transported to the liver .

A). In patients A's case , she is not a vegetarian, but she suffers from autoimmune disorder , which causes autoantibodies against parietal cells, thus parietal cells are destroyed which causes decreased IF production , thus vit b12 absorption is lesser causing deficiency.  

Treatment given to this patient include vit b12 supplements given by injections either weekly or monthly. Oral supplements can be given , but it requires larger dose than normal since IF is absent for vitb12 absorption. Thus vit b12 can be given by parenteral route . Life long the supplements must be given. The treatment must be started earlier, if not it can lead to neurological manifestations and gastric cancer is more susceptible in this patient so patient must be on regular check up . With vitb12 supplement prognosis os good .

B). Despite correcting his vegan diet , the patient vitb12 level is not corrected because he had undergone gastric bypass surgery 3 years back , thus IF is not produced since IF is produced in parietal cells in gastrum . Thus her vit b12 level continues to be low . It took 3 years for the patient to develop symptoms because usually vit b12 is stored in liver and it can meet the vit b12 requirements of body for 3 to 5 years , after that only the symptoms starts to appear and anemia starts to exaggerate and worsen , which can be met by vit b12 supplements.  

C ). Patient C has chrons disease. It is an inflammatory bowel disorder, which causes inflammation of bowel mainly smallintestine and colon . Thus leading to fatigue, diarrhoea ,malnutrition and weight loss . Mostly ileum is affected and it affects deep layers of the intestine. Most common cause may be due to abnormal immune responses or it may be hereditary. Complications of chrons disease is , it leads to bowel obstruction and narrowing of lumen , which needs immediate surgical resection. Sometimes fistulas are formed an ulcers are more common.

Thus due to obstruction of Bowel which is a threatening complication of chrons disease ileal resection is performed.  

Terminal ileal resection is an surgery done to remove terminal ileum mainly in disease like chrons and tuberculosis. It is indicated in cases of obstruction and fistula and in high risk of malignancy .

Amino acids and glucose is mostly absorbed in jejunum ,terminal ileum is responsible for absorption of vit b12 and bile salts and water. Due to this vitb12 deficiency will manifest and also fat is not absorbed leading to steatorrhea that is unabsorbed fat in stool . Dehydration will also be seen . Thus excess fat is seen in colon wich binds with calcium. Thus oxalate which forms complex with calcium will be reabsorbed leading to kidney stones .

Treatment and prognosis for this patient is:

Meals will be split up and person takes 5 to 6 meals a day . Water will be taken after meal not along with it . Protein rich food and less sugar and less fat substance is taken . If vit A,D,K,E malabsorption occurs it can be supplemented to meet the bodys need . Vit b12 supplements given . Low oxalate food taken . If the patient follow this strategy prognosis is good .