Endocrine Conditions - NCLEX-PN

GLUT-2 is the primary carrier for glucose transport into pancreatic beta cells. It does not depend on insulin to function. It thus aids the pancreatic beta cells sense glucose levels in the blood, which are then triggered to release insulin. GLUT-4 is active primarily in adipose and muscle tissue.

The first onset of diabetes is generally marked by the following three signs: polyuria - frequent urination, polydypsia - increased thirst & fluid intake, and polyphagia - increased appetite. In children with type 1 diabetes, enuresis (involuntary urination) is often the first sign noticed by parents, along with unexplained weight loss and recurrent infections.

Conn syndrome (primary hyperaldosteronism) is hypertension due to elevated levels of aldosterone. High aldosterone causes excretion of potassium and retention of sodium, which leads to water retention and increase in blood pressure. While elevated levels of vasopressin (antidiuretic hormone) would also cause hypertension, Conn syndrome refers to the hypersecretion of aldosterone.

Insulin activates sodium-potassium ATPase in skeletal muscle cells causing an influx of potassium. Under certain circumstances, an incorrectly administered injection of insulin may kill patients due to its ability to acutely suppress plasma potassium concentrations.

All of these symptoms are associated with a higher risk of developing diabetes. Turner syndrome is also know as XO, where the individual is a female, and is monosomic for the X-chromosome. Individuals with Turner syndrome are also at higher risk of heart disease, and hypothyroidism, and they are sterile. Down's syndrome is caused by trisomy of chromosome 21, and involves elevated risks for mental impairment, heart disease, and certain cancers. Kleinfelter's syndrome patients have the XXY-chromosomal expression. They are at a higher risk than the classically male or female public for osteoporosis, hypogonadism, and cardiovascular disorders.

80% of cases of Cushing's disease are caused by adrenocorticotropic hormone (ACTH)-secreting adenomas of the anterior pituitary. High ACTH ends up causes adrenal hyperplasia, which leads to secretion of extra cortisol. Corticosteroid use is the leading cause of Cushing syndrome, rather than Cushing's disease.

Smokers have higher levels of the chemical thiocyanate, a degradation product of cyanide in tobacco smoke, which can block iodine uptake by the thyroid. A high oxalate diet is associated with kidney stones, asbestos exposure is associated with mesothelioma, and nonsteroidal anti-inflammatory drugs (NSAIDs) use, while associated with several gastric disorders, has not been shown to have a significant effect on thyroid function.

Primary hyperparathyroidism is most commonly due to a parathyroid adenoma. 80-90% of cases of primary hyperparathyroidism are due to parathyroid adenoma. 10-15% cases are due to parathyroid hyperplasia, and parathyroid carcinoma accounts for 1-5% of all cases.

Renal failure is by far the most common cause of secondary hyperparathyroidism**.** If kidneys are unable to convert vitamin D to its active form, serum vitamin D levels will drop. Lower vitamin D levels reduce the absorption of calcium in the intestines and reduce the kidneys' ability to resorb calcium from the urine. In addition, if the kidneys are unable to adequately excrete phosphate, calcium phosphate forms, which further lowers free calcium levels in the blood. Poor nutrition is not a common cause of secondary hyperparathyroidism, though low vitamin D levels due to malabsorption can be a contributing factor. Pituitary tumors can be seen with hyperparathyroidism when part of multiple endocrine neoplasia type I, but this is not as common as renal failure. Bone cancers are more often associated with elevated calcium levels, resulting in low or undetectable parathyroid hormone levels.

Hypothyroidism usually involves weight gain so a lower calorie diet with frequent small meals are recommended. High fiber, low calorie diets and stool softeners will help to alleviate these symptoms. Antiglycemics and hemoglobin A1C tests are indicated for diabetics.

Tetany is a complication due to hypocalcemia which can occur if the parathyroid glands which control calcium balance are accidentaly injured during thyroidectomy. Tetany is associated with nerve excitability and sustained muscle contractions, or spasms. Tetanus, bone pain, and oliguria are not associated with complications of a thyroidectomy. Goiter is a manifestation of an overactive thyroid.

Corticosteroids may lead to bone loss, especially after long term treatment (over 3 months). Calcium and vitamin D supplementation can help prevent these side effects. The client should also be advised to start a low impact exercise regimine if possible, and if necessary take a bisphosphonate drug.

The correct answer is prednisone. Of all the medications listed, prednisone is the only medication that is known to cause hyperglycemia.

Prednisone has a number of side effects including hyperglycemia, acne, headache, restlessness, insomnia, nausea, vomiting, and weight gain, among others.

Clindamycin's side effects include diarrhea (including Clostridium difficile), and less commonly nausea, vomiting, and abdominal pain, among others, but not hyperglycemia.

Ketorolac's side effects include renal toxicity, tinnitus, heartburn, diarrhea, and abdominal pain, among others, but not hyperglycemia.

Lisinopril's side effects include hypotension, lightheadedness, angioedema, and barky cough, among others, but not hyperglycemia.

Simvastatin's side effects include muscle pains/aches, muscle weakness, and less frequently confusion, and electrolyte disturbances, but not hyperglycemia.

Type I diabetes is an autoimmune process that typically presents in young children in the form of DKA (diabetic ketoacidosis). This potentially life threatening condition is treated with IV insulin. Type II diabetes is insulin resistance, and is found in older adults (typically those who are overweight).

The correct answer is "to prevent lactic acidosis while hospitalized." This is the correct answer because a known side effect of metformin use is development of lactic acidosis (a form of metabolic acidosis). Patients who are hospitalized, especially if hospitalized for infections, like pneumonia, are independently at an elevated risk of developing a lactic acidosis. As such, to minimize the risk of lactic acidosis, a modifiable risk factor, metformin use, is frequently temporarily discontinued while inpatient. Patients on metformin are frequently switched to sliding-scale insulin as inpatients, as this allows for adequate glycemic monitoring, titration, and control. Once they are stable for discharge and the cause of their hospitalization is addressed and treated, most can be safely discharged home on metformin without issue.

While numerous measures are carried out while patients are hospitalized to prevent myocardial infarction, stroke, headache, and depression, the switching of metformin to sliding-scale insulin is not performed specifically for any of those reasons.

The 5 year survival rate for aplastic carcinoma of the thyroid is 7-14%. The 5 year survival rates of papillary, medullary, and follicular thyroid carcinomas are close to 100% for stage I cancers. Survival rates decrease to approximately 50% for stage IV papillary and follicular carcinomas and 28% for stage IV medullary carcinoma.

Peripheral neuropathy is a common condition among elderly diabetic patients. Due to the loss of sensation in fingers, arms, legs, and toes, these patients must be aware of their surroundings, use proper foot care, inspect feet daily (with a mirror if the patient is elderly or has decreased joint mobility), wear well-fitting shoes, avoid heating pads on feet, avoid walking barefoot, and cut toenails straight across without rounding corners. It is also important for the patient to avoid exercise when their condition is poorly controlled due to the increased demand for glucose. This patient must be sure to check the temperature of baths before using them, as the potential for burns is high in those with decreased sensation and neuropathy.

Cystic fibrosis is a disorder that mainly affects the lungs, but also alters fat metabolism from a lack of pancreatic enzymes. The disorder is treated with pancreatic enzyme replacement, which is best absorbed when taken before meals or with food. The best diet for cystic fibrosis is low-fat and cholesterol-restricted with good sources of protein, such as fruit, vegetables, lean meats, and cereals. These patients must avoid fatty, marbled meats such as bacon, fatty foods such as avocado, egg yolks, and butter. During illness, patients with cystic fibrosis have higher calorie and protein demands.

Patients with Addison’s disease are more susceptible to becoming dehydrated and may lose salts more quickly than others. Because of this, it is important to make sure these patients have a well-rounded diet with an emphasis on fluids. Protein, whole grains, and fibers are routinely recommended in a healthy, balanced diet, but it is not recommended to have a sodium-restricted diet.

Prolactinomas (prolactin-secreting) make up 30% of functional pituitary adenomas. The second most common type are somatotrophic (growth hormone-secreting) adenomas, which make up 15%, followed by gonadotrophic (gonadotrophin-releasing) adenomas, which make up 10% of reported cases. Null cell adenomas are non functional (they do not secrete hormones).