progression of type Ⅰ diabetes mellitusOvert manifestations of diabetes mellitus tend to develop once >90% of beta cells are destroyed.
Although antibodies against islet antigens are detected in a large number of patients, they are thought to play a permissive role in disease pathogenesis; the destruction of beta cells occurs primarily through ☆cell-mediated immunity. Infiltration of islets by inflammatory cells is called insulitis and is more prominent during the early stages of disease. endocrinologyUWorld Jun 29, 2020, 8:03 AM HirotoShishido
pathogenesis of diabetic neuropathyAccumulation of glycosylationend products and sorbitol altered metabolism and increased oxidative stress
☆Endoneureal arteriolar hyalinization
Occlusion of vasa nervorum with nerve ischemia
☆Length-dependent axonopathy
(short→ positive(eg pain), long→ negative(eg numbness)) endocrinologyUWorld Jun 29, 2020, 6:05 AM HirotoShishido
conditions that cause lab values the same as CKD(seconary hyperparathyroidism)hyperphosphatemia(eg tumor lysis syndrome)
thyroid adenomaBenign solitary growth of the thyroid. Most are nonfunctional (“cold”), can rarely cause hyperthyroidism via autonomous thyroid hormone production (“hot” or “toxic”).
Most common histology is follicular (arrows in A ); absence of capsular or vascular invasion (unlike follicular carcinoma). endocrinology Jun 29, 2020, 5:28 AM HirotoShishido
Nodular: toxic multinodular goiter, thyroid adenoma, thyroid cancer, thyroid cyst. endocrinology Jun 29, 2020, 5:26 AM HirotoShishido
postpartum thyroiditisSelf-limited thyroiditis arising up to ★1 year after delivery.
a form of painless autoimmune thyroiditis
Presents as transient hyperthyroidism, hypothyroidism, or hyperthyroidism followed by hypothyroidism. Majority of women are euthyroid following resolution. Thyroid usually painless and normal in size.
(⇔painful, tender goiter= subacute thyroiditis) endocrinologyUWorld step2CK Jun 29, 2020, 5:15 AM HirotoShishido
presentation of acromegaly☆left ventricular hypertrophy,
☆hypertrophic arthropathy(hyperplasia of articular chondrocytes and synovial hypertrophy→ degeneration of articular cartilage and periarticular bone),
prognathsm,
carpal tunnel syndrome,
↑ risk of colorectal polyps and cancer,
diaphoresis endocrinologyUWorld Jun 29, 2020, 5:09 AM HirotoShishido
pathogenesis/ presentation/ complications/ treatment of pituitary apoplexyAcute pituitary hemorrhage
Usually occurs in preexisting adenoma
treatment for diabetes insipidus(DI)central DI
desmopressin, hydration
nephrogenic DI
☆hydrochlorothiazide(HCTZ), NSAIDs(indomethacin)→↑aquaporin2, amiloride→lithium, hydration, dietary salt restriction
Thiazides appear to reduce renal water losses in NDI by inducing a mild volume depletion that ☆increases sodium and water reabsorption in the proximal tubule.
Infants with NDI cannot freely replace ongoing water losses, and early treatment is essential for preventing associated mental and physical growth retardation. endocrinologyUWorld Jun 28, 2020, 10:06 AM HirotoShishido
cause of hereditary hypothalamic diabetes insipidus (DI)☆point mutation in neurophysin Ⅱ endocrinologyUWorld Jun 28, 2020, 9:56 AM HirotoShishido
permanent and transient diabetes insipidus(DI)Damage to the more distal portions of the hypothalamic-hypophyseal tract (ie, below the infundibulum) typically causes transient DI because the cell bodies of the magnocellular neurons remain intact.
However, ☆hypothalamic injury results in death of the magnocellular neurons, causing ☆permanent central DI. endocrinologyUWorld Jun 28, 2020, 9:53 AM HirotoShishido
zinc-finger motifsthe most commonly identified DNA-binding domain in humans
Zinc-finger motifs are composed of chains of amino acids bound together around a zinc atom via linkages with cysteine (and sometimes histidine) residues. This forms a stable, finger-shaped structure containing 2 antiparallel β- strands and an α- helix.
Many ☆transcription factors(→ intracellular receptors) use multiple zinc-finger motifs to recognize specific genes and alter their activity. endocrinologybiochemistryUWorld Jun 28, 2020, 9:16 AM HirotoShishido
how does insulin promote glycogen synthesis?PI3K(phosphoinositide-3 kinase) promotes glycogen synthesis by activating ☆protien phosphatase, an enzyme that dephosphorylates glycogen synthesis, leading to its activation endocrinologyUWorld Jun 28, 2020, 8:16 AM HirotoShishido
treatment for hypoglycemia• If the patient is conscious:
Oral glucose 15-20 g
fast acting carbohydrates
• If the patient is unconscious (or unable to ingest glucose):
medical setting→ IV dextrose
nonmedical setting→ ☆IM glucagon
→recheck POC glucose after 15mins
*suspected severe hypoglycemia should be treated immediately, without waiting for the results of blood glucose testing endocrinologyUWorld Jun 28, 2020, 8:01 AM HirotoShishido
how does adrenaline regulate insulin levelsinsulin release ↓by α2, ↑by β2 stimulation
α2 mediated inhibitory effects is predominant, causing sympathetic stimulation to lead to overall inhibition of insulin secretion endocrinologyUWorld Jun 26, 2020, 2:32 AM HirotoShishido
mutation in RET proto oncogeneRET cause for receptor tyrosine kinase
cause ☆multiple endocrine neoplasia type2 (A and B) (MEN2A, B)
areas particulary susceptible to neuropathic ulcersare points of localized pressure created by a shoe or weight-bearing bones of the foot (eg, ☆plantar surface of the first metatarsal head)
A wound in this area often goes unnoticed (due to lack of pain sensation and being hidden by socks orshoes) and can develop into a nonhealing foot ulcer. cardiologyendocrinologyUWorld Jun 25, 2020, 9:45 PM HirotoShishido
hyercalcemia occuring in patients with granulomatous diseasegranulomatous diseases (eg, sarcoidosis, tuberculosis) can have ☆PTH-independent conversion due to expression of 1-a-hydroxylase in activated macrophages.
(A similar process can occur in Hodgkin disease and some non-Hodgkin lymphomas.) endocrinologyUWorld Jun 25, 2020, 12:29 AM HirotoShishido
alpha (α) cell failurepatients with long standing diabetes (ie >5 years) frequently have alpha cell failure with ☆decreased glucagon secretion and therefore have an even greater risk of rapid hypoglycemia
patients with pancreatogenic diabetes(eg secondary to chronic pancreatits) also typically have inadequate alpha cell reserve and experience frequent hypoglycemia endocrinologyUWorld new question Jun 22, 2020, 4:20 AM HirotoShishido
thyroid cancers which are associated with radiation exposure☆papillary and follicular carcinoma endocrinologyUWorld SIM2 Jun 20, 2020, 5:37 AM HirotoShishido
