Lecture 10 - Primary hyperparathyroidism, osteoporosis

etiology primary hyperparathyroidism

• parathyroid adenoma

• primary hyperplasia of parathyroid

• parathyroid carcinoma

primary hyperparathyroidism is characterized by abnormal regulation of _________

pth secretion by calcium

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are caused by mutations in the dna of parathyroid cells

parathyroid adenomas

clinical features primary hyperparathyroidism

• asymptomatic hypercalcemia + elevated intact pth conc

• clinical pic hypercalcemia

• patients w/ osteoporosis, fx, low bone density or nephrolithiasis

• sumptomatic severe hypercalcemia (parathyroid crisis) or osteitis fibrosa cystic

signs and symptoms primary hyperparathyroidism

stones, bones, abd groans and pyschic moans

• cns effects - memory loss, lethargy, confusion

• neurom - prox myopathy, arthritis

• cardiovasc - htn, brady

• renal - stones

• gi - nausea, constipation, epulis

• band keratopathy, metastatic calcification

clinical characteristics of bone disease in PHPT

bone pain, generalized demineralization bone (@ cortical sites), manifestations osteitis fibrosa cystican→ subperiosteal bone resorption @ hands, bone cysts, brown tumours, patho fx

labs PHPT

hypercalcemia, low-normal phosphorus, hyperchloremic metabolic acidosis, markers bone turnover

what is measurement urinary calcium excretion required for

distinguishing phpt from familial hypocalciuric hypercalemia (increased in phpt)

what can obscure lab results phpt

vit d deficiency

parathyroid crisis

severe hypercalemia, high ca conc, cns dysfxn (agitation, lethargy, confusion, coma), abd pain, peptic ulcer, pancreatitis

treatment phpt

excision abnormal parathyroid tissue - parathyroidectomy

when does acute postop hypocalcemia occur after parathyroidectomy for phpt

severe bone mineral deficits present (hungry bones syndrome) or injury to all normal parathyroid glands

what should patients avoid after parathyroidectomy for phpt

avoid inativity, mod. calcium intake, avoid thiazides and lithium, lots vit d

meds for phpt if surgery not possible

estrogen-progestin in postmenopausal, biphosphonates, raloxifene, calcimimetics

treatment parathyroid crisis

rehydration, furosemide, biphosphonate, zolendronate, calcitonin, iv glucocorticoids, dialysis, urgent parathyroidectomy

osteoporosis

reduction strength of bone leading to fx from loss bone tissue and deterioration skeletal microarchitecture

primary osteoporosis - causes

reduced bone mass and fx in postmenopausal women or old men from age due to

• estrogen deficiency

• progressive deficits renal and intestinal fx

• failure to reach peak bone mass in young

secondary osteoporosis - causes

bone loss from

• endocrinopathies - thyrotoxicosis, hyperprolactinemia, phpt, DM

• gi - vit d deficiency, chronic liver disease, malabsorption

• hema - hemochromatosis, leukemia, mm

• glucocorticoids, OCs, immunosuppressants, antiseizure meds

• genetics - hypophosphatasia, osteogenesis imperfecta

clinical manifestations osteoporosis

no symptoms until fx (vertebral is most common)

colles fx

common osteoporosis fx in women right after menopause

risk factors for osteoporosis fx

history fx, female sex, old, white, low calcium intake, estrogen deficiency, alcoholism

investigations osteoporosis

xray, bmd, dxa

cbc, calcium, renal + hepatic fxn, vit d

bone formation markers - akp, osteocalcin

bone resorption markers - n-telopeptide, c-telopeptide, deoxypyridinoline

pharma therapy for postmenopausal women w/ osteoporosis

antiresorptives - biphosphonates, SERM, tibolone

anabolic therapy - parathyroid, strontium, steroids

se biphosphonates

upper gi, jaw osteonecrosis, bone pain, flu symptoms

COs biphosphonates

hypersensitivity, hypocalcemia, esophagus abnormalities

COs HRT for osteoporosis

abnormal vaginal bleeding, thrombophlebitis or v thromboembolic disorders, breast carcinoma