Concepts of Endocrine Disorders

Example Solution to the Assignment: Concepts of Endocrine Disorders 

Question 1: Syndrome of Antidiuretic Hormone (SIADH)

Normally, the secretion of antidiuretic hormone (ADH) is influenced by plasma osmolality. However, SIADH results when the ADH secretion is excessive regardless of the plasma osmolality, thus leading to increased water retention by kidneys and the resultant electrolyte imbalances worse, which is dilutional hyponatremia (Mentrasti et al., 2020). The patient presentation relates to such hyponatremia.

Different factors predispose an individual to SIADH development, including advanced age, drug use, brain disorders, and malignancies. The patient in the case study had some of these factors that might have predisposed her to develop the condition. She is older than 50 years, has type 2 diabetes mellitus, has a long-standing history of cigarette smoking, and is on different medications for managing depression, including antidepressants.

Patients with advanced age may develop ineffective secretion of ADH due to medications such as antidepressants and NSAIDs that interfere with renal function (Al-Hinai et al., 2021). Further, a history of smoking is suggestive of undiagnosed lung malignancy and emphysema that has been associated with SIADH. In addition, the patient had a history of falls from which she may have sustained intracranial bleeding, thus resulting in SIADH (Mentrasti et al., 2020). These factors should be investigated and appropriately addressed.

Question 2: Pathophysiology of three P`s in type I diabetes Mellitus

Patients with type 1 diabetes mellitus (DM) have autoimmune destruction of the pancreas’s β-islet cells, leading to absolute insulin deficiency in the body (Nigro et al., 2018). They, therefore, have disorders in the metabolism of glucose, resulting in high serum levels of glucose. As a result of this hyperglycemia, the renal threshold for glucose is overcome, and glucose is passed into the urine (Nigro et al., 2018). 

Glycosuria increases the osmotic potential of the urine, thus leading to increased water loss resulting in polyuria. Consequently, the individual becomes dehydrated and the thirst center is stimulated to increase the water intake to offset the dehydration (Banday et al., 2020). This increase in water intake is polydipsia. Further, glucosuria also reduces the body’s carbohydrates, and the individual increases food intake to replenish the lost sugars (Nigro et al., 2018). Polyphagia refers to this increased food intake in DM.

Question 3: How Genetics and Environmental Factors Contribute to Type 1 DM

Type 1 DM results from autoimmune destruction of pancreatic cells. It is estimated that 50% of the affected individuals have a hereditary genetic predisposition, as witnessed by the fragility at chromosome 6p21 and the insulin gene found in chromosome 11p15 (Blanter et al., 2019). In addition to this predisposition, the affected individuals may be triggered by environmental factors such as obesity and viral infection, leading to the development of diabetes mellitus, especially in the younger population (Nigro et al., 2018).

Question 4: Pathology of Type 2 DM

Type 2 DM, in contrast to type 1 DM, results from absolute insulin deficiency, results from relative insulin deficiency due to reduced secretion of insulin by the pancreas, increased insulin resistance by the peripheral tissues, or both (Galicia-Garcia et al., 2020). It can also be due to increased levels of insulin counterregulatory hormones. This relative insulin deficiency leads to reduced utilization of glucose in the affected individual, and the lipids are metabolized instead (Banday et al., 2020). This is the hallmark of hyperglycemia and other patient presentation encountered in type 2 DM.

Question 5: Causes of Hypothyroidism

Hypothyroidism is the low secretion of thyroid hormones by the thyroid gland. Such low secretion can be due to disorders of the thyroid gland, pituitary gland, or hypothalamus. The disorders of the thyroid gland include the use of amiodarone, iodine deficiency, thyroidectomy, thyroid radiation, and Hashimoto’s thyroiditis (Chiovato et al., 2019). These conditions contribute to the majority of hypothyroidism cases, although hypopituitarism and deficiency of hypothalamus hormones (McDermott, 2020).

References

Al-Hinai, A., Al-Murshedi, F., Al-Nabhani, D., & Al-Thihli, K. (2021). Syndrome of inappropriate antidiuretic hormone secretion in a patient with uncontrolled tyrosinemia type 1. Sultan Qaboos University Medical Journal, 21(2), e312–e315. https://doi.org/10.18295/squm