Endocrine & Metabolic

Reference: Davidson 23rd; P-674

Reference: Davidson 23rd; P-746

Explanation: Hypothermia exists when the body’s normal thermal regulatory mechanisms are unable to maintain heat in a cold environment and core temperature falls below 35°C

Reference: Davidson 23rd, Page: 644, Box : 18.14

Weight loss with low grade evening fever, cough and night sweats indicates tuberculosis.
Weight loss in spite of good appetite or high food intake—thyrotoxicosis, diabetes mellitus, malabsorption syndrome.
Weight loss with pigmentation and hypotension—Addison’s disease.

 Pregnancy is the most common cause of secondary amenorrhea (the absence of menstruation for more than three cycles in a previously menstruating woman). Davidson emphasizes that pregnancy should always be ruled out first in women presenting with amenorrhea. Harrison adds that other common causes of secondary amenorrhea include polycystic ovary syndrome (PCOS), hyperprolactinemia, and thyroid disorders.

Stem Breakdown:

Heat intolerance, weight loss, palpitations: These symptoms suggest hyperthyroidism.
Diffuse thyroid enlargement and exophthalmos: These signs strongly indicate Graves’ disease, an autoimmune form of hyperthyroidism where antibodies stimulate the thyroid to overproduce thyroid hormone.
Option Analysis:

A) Propylthiouracil (PTU): PTU is an antithyroid medication used to inhibit thyroid hormone synthesis. While it is an important treatment for Graves’ disease, it is not the first-line treatment in an acute setting. Beta-blockers are initially used to control symptoms such as palpitations and tachycardia.
B) Radioactive iodine: Radioactive iodine is a definitive treatment for Graves’ disease, as it destroys overactive thyroid tissue. However, it is not used as an initial treatment to control acute symptoms.
C) Beta-blockers: This is the correct answer. Davidson and Harrison explain that beta-blockers (e.g., propranolol) are used to manage the adrenergic symptoms of hyperthyroidism (palpitations, tremors, anxiety) while more definitive treatments (e.g., antithyroid medications or radioactive iodine) are initiated.
D) Thyroidectomy: Thyroidectomy is reserved for patients who fail medical therapy or cannot tolerate other treatments. It is not used as initial treatment for hyperthyroidism.

Reference: Davidson 23rd Box 21.2

Reference: Davidson 23rd; P-649

It will be cold intolerance , Reference: Davidson 23rd, Box-18.7

Reference: Davidson 23rd, Page : 646

Answer: A
Explanation: Radioactive iodine therapy is the most common treatment for Graves’ disease. Davidson explains that radioactive iodine selectively destroys thyroid tissue, leading to reduced thyroid hormone production. Harrison notes that this therapy is particularly effective in older patients and those with contraindications to surgery. Methimazole and beta-blockers are often used as adjunctive therapies but are not definitive treatments.

Explanation: Iodine is required for synthesis of thyroid hormones

Explanation: Acromegaly is caused by growth hormone (GH) secretion from a pituitary tumour, usually a macroadenoma, and carries an approximate twofold excess mortality when untreated.

Reference: Davidson 23rd; P-637

Stem Breakdown:

Confusion, ataxia, and nystagmus: This classic triad of symptoms is highly suggestive of Wernicke's encephalopathy, a neurological disorder associated with thiamine (vitamin B1) deficiency.
Chronic alcohol use: Chronic alcoholism is the most common cause of thiamine deficiency, leading to Wernicke's encephalopathy.
Rapid improvement with thiamine: This confirms that the symptoms were due to thiamine deficiency, which is rapidly reversible with appropriate supplementation.
Option Analysis:

A) Wernicke’s encephalopathy: This is the correct diagnosis. Davidson and Harrison both highlight that Wernicke’s encephalopathy is caused by thiamine deficiency, commonly seen in chronic alcoholics. The classic symptoms include confusion, ataxia, and ophthalmoplegia (nystagmus or other eye movement abnormalities). Rapid improvement with thiamine supports this diagnosis.
B) Korsakoff’s syndrome: Korsakoff's syndrome is a chronic sequela of untreated Wernicke’s encephalopathy, characterised by irreversible memory loss and confabulation. It does not cause rapid neurological improvement with thiamine administration.
C) Alcohol withdrawal: Alcohol withdrawal causes symptoms such as tremors, agitation, and hallucinations, but it does not typically present with the triad of confusion, ataxia, and nystagmus.
D) Hepatic encephalopathy: Hepatic encephalopathy occurs in patients with liver failure and is due to elevated ammonia levels. It presents with altered mental status but not with the other signs of Wernicke's (ataxia, nystagmus).

Explanation: Option B,C, D Causes pitting oedema.

Reference: Davidson 23rd, Page: 760
Explanation: Median nerve compression is more common in diabetes causing carpal tunnel syndrome.

Parathyroid glands are derived from the epithelial lining of the third and fourth pharyngeal pouches, with the superior glands arising from the fourth pouch and the inferior glands arising from the higher third pouch.

Davidson 23rd, Box-19.28

Reference: Davidson 23rd, Page: 746 , Box : 20.26

Reference: Davidson 23rd; P-637

Explanation: Dry (or neurological) beri-beri manifests with chronic peripheral neuropathy and with wrist and/or foot drop, and may cause Korsakoff’s psychosis and Wernicke’s encephalopathy

Explanation: Red cell folate levels are a more accurate indicator of folate stores and tissue folate deficiency.

Reference: Davidson 23rd; P-637, box: 18.8

Hypercarotenaemia occurs due to excessive ingestion of carotene-containing vegetables or in situations of impaired metabolism such as hypothyroidism or anorexia nervosa.

A yellowish discoloration is seen on the face, palms and soles but not the sclera or conjunctiva, and this distinguishes it from jaundice 


Macledo 14th/P-26

Reference: Davidson 23rd , Page : 717 , Box : 19.34

Reference: Davidson 23rd , Page : 1233
Explanation : Niacin deficiency ( Vitamin B3 ) - pellagra can also seem in carcinoid syndrome.

Reference: Davidson 23rd; P-640

Reference: Davidson 23rd, Box-29.1

Stem Breakdown:

Polyuria, polydipsia, and weight loss: These symptoms indicate uncontrolled hyperglycemia, suggesting diabetes mellitus.
Fasting blood glucose of 230 mg/dL and HbA1c of 10.5%: These levels confirm the diagnosis of diabetes, with an HbA1c >6.5% indicating poorly controlled blood glucose.
Option Analysis:

A) Insulin: Insulin is used in type 1 diabetes and in type 2 diabetes when oral agents fail to achieve glycaemic control. However, for most newly diagnosed type 2 diabetes patients, oral hypoglycemic agents are first-line unless there are signs of diabetic ketoacidosis or severe hyperglycemia.
B) Metformin: This is the correct answer. Davidson and Harrison both recommend metformin as the first-line therapy for type 2 diabetes, as it effectively lowers blood glucose by improving insulin sensitivity and reducing hepatic glucose production without causing significant hypoglycemia. It is typically used in patients who are overweight, as it does not promote weight gain.
C) Sulfonylureas: Sulfonylureas (e.g., glipizide, glyburide) are effective in lowering blood glucose but are associated with weight gain and a higher risk of hypoglycemia compared to metformin. They are often used as second-line agents if metformin alone is insufficient.
D) DPP-4 inhibitors: DPP-4 inhibitors (e.g., sitagliptin) help increase insulin secretion and reduce glucagon secretion but are generally used as add-on therapy to metformin. They are not as effective as first-line treatment for most patients with type 2 diabetes.

Reference: Davidson 23rd , Page : 712 , Box : 29.32

Reference: Davidson 23rd; P-746

Explanation: Metformin is used as first-line therapy for type 2 diabetes, irrespective of body weight

Reference: Davidson 23rd; P-644

Reference: Davidson 23rd, Page: 733 Box : 20.9

Some major endocrine glands are not controlled by the pituitary. These include the parathyroid glands (regulated by calcium concentrations), the adrenal zona glomerulosa (regulated by the renin–angiotensin system) and the endocrine Pancreas

Reference: Davidson 23rd, Page: 736 , Box : 20.15

Reference: Davidson 23rd, Page: 733 , Box : 20.9

Reference: Davidson 23rd; P-644

Reference: Davidson 23rd; P-644