Thyroid States
This condition features weight loss, heat intolerance, and tachycardia.
What is hyperthyroidism?Excess thyroid hormone increases basal metabolic rate and sympathetic activity, causing catabolism and heat production.
Hormone that increases blood calcium by bone resorption and renal reabsorption.
What is parathyroid hormone (PTH)?PTH activates osteoclasts and 1-alpha hydroxylase → increases serum Ca²⁺ and decreases PO₄³⁻.
Three zones of adrenal cortex: glomerulosa, fasciculata, reticularis.
What are the layers producing mineralocorticoids, glucocorticoids, and androgens?Each zone has specific enzymes: aldosterone synthase, 11β-hydroxylase, 17α-hydroxylase.
Autoimmune destruction of beta cells → absolute insulin deficiency.
What is type 1 diabetes?Anti-islet antibodies → no insulin → ketoacidosis risk.
Pancreatic hormone that lowers blood glucose by cellular uptake.
Insulin
The autoimmune cause of hyperthyroidism with exophthalmos.
What is Graves’ disease?TSH-receptor antibodies stimulate thyroid → overproduction of T3/T4; orbital inflammation causes eye protrusion.
Condition with hypercalcemia, kidney stones, and “bones, stones, groans, moans.”
What is hyperparathyroidism?Excess PTH → excessive bone breakdown and renal Ca²⁺ retention → pathological calcification.
Primary adrenal insufficiency with hyperpigmentation and salt craving.
What is Addison’s disease?Autoimmune destruction → cortisol + aldosterone deficiency → ACTH rises → melanin stimulation.
Insulin resistance with relative insulin deficiency, often in obesity.
What is type 2 diabetes?Peripheral tissues resist insulin → pancreas compensates → eventual beta cell burnout.
Negative feedback: high cortisol inhibits release of ACTH.
What is the HPA axis feedback loop?Maintains homeostasis; prevents excessive glucocorticoid production.The HPA axis, or hypothalamic-pituitary-adrenal axis, is a major neuroendocrine system that controls the stress response. When stress is detected, the hypothalamus releases corticotropin-releasing hormone (CRH), which signals the pituitary gland to release adrenocorticotropic hormone (ACTH). ACTH then travels to the adrenal glands, prompting them to release cortisol, a stress hormone that helps the body cope with a perceived threat.
Severe hypothyroidism in adults, characterized by facial puffiness and cold intolerance.
What is myxedema?Lack of thyroid hormone slows metabolism; mucopolysaccharide deposition in skin causes non-pitting edema.
Hypoparathyroidism leads to this neuromuscular symptom due to low calcium.
What is tetany (or Chvostek/Trousseau sign)?Low Ca²⁺ increases neuronal excitability → spontaneous muscle contractions.
Excess cortisol causes central obesity, moon face, and buffalo hump.
What is Cushing’s syndrome?Glucocorticoid excess → protein catabolism, fat redistribution, and insulin resistance.
Life-threatening complication of DKA with fruity breath and Kussmaul breathing.
What is diabetic ketoacidosis?Lack of insulin → fat breakdown → ketone production → metabolic acidosis.
Graves’ disease disrupts this thyroid feedback loop.
What is TSH negative feedback?Excess T3/T4 should suppress TSH, but autoantibodies mimic TSH → no suppression.
Lab triad in primary hypothyroidism: high TSH, low free T4, and positive anti-TPO antibodies.
What is Hashimoto’s thyroiditis?Autoimmune destruction of thyroid → reduced hormone synthesis → pituitary increases TSH to compensate.
Most common cause of hypoparathyroidism post-thyroidectomy.
What is surgical removal/damage to parathyroid glands?Parathyroids are embedded in thyroid; accidental removal → acute PTH deficiency.
A Sodium level of 112 indicate?
What is an EXPECTED abnormal electrolyte value with Addisonian Crisis?
HbA1c goal for most diabetic patients (ADA).
What is <7.0%?Reflects average blood glucose over 2–3 months; reduces microvascular complications.
In Addison’s, low cortisol → high ACTH → hyperpigmentation.
What is loss of negative feedback?Cortisol normally inhibits pituitary ACTH; deficiency removes inhibition.
A life-threatening complication of Graves’ disease
What is thyroid storm, also known as accelerated hyperthyroidism (or thyrotoxic crisis). It’s more likely when severe hyperthyroidism is untreated or treated inadequately.
In chronic kidney disease, secondary hyperparathyroidism occurs due to low active vitamin D and high phosphate.
What is renal osteodystrophy?Kidneys fail to convert vitamin D → hypocalcemia → compensatory PTH increase → bone resorption, breaking down old bone.
adrenal gland hormones
This Increases sodium absorption, potassium loss by the kidneys, Metabolism of all nutrients, Regulates blood glucose levels, Decreases effects of stres
Blood glucose <60 mg/dL
A sign that does not present in hyperglycemia
TRH → TSH → T3/T4 → inhibits TRH/TSH. This is the classic example.
What is the hypothalamic-pituitary-thyroid axis?Multi-level negative feedback maintains euthyroid state.