8/3/2019 Metabolic and Endocrine Disorder of Bone

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OSTEOPOROSIS PRIMARY HYPERPARATHYROIDISM

Causes idiopathicBone loss is excessiveSupposition of bone is reduced

AdenomaAdenocarcinomaIdiopathic hyperplasia of parathyroid gland

Risk factors Post menopausal womenGeneticReduced calcium intakeLack of exerciseSmoking

Middle aged women (predominantly)

Clinical

Features

Rate of loss bonemineral:1-2%/year (postmenopausal women)

5-8%/year (1/4cases)

2x faster in womenthan men

Accentuated in :Cushing syndromeThyrotoxicosis1 hyperparathyroidism

Severe cases associated with:Bone painBone cyst(osteitis fibrosa cystica)Phatological fracturesBrown tumorsRenal colic (stones)Mental changes : depression, emotionalliability, poor mentation n memory defects

Increased incidence of peptic ulcerChronic pancreatitisHypertension

May present as central giant cell lesion of jaws

Diagnosis Biochemical changes :Increased parathomone levelIcreased serum calcium levelIncreased AP (maybe)Increased urinary secretion of calcium and phosphateDecreased serum phosphate level

Histopathologic

Features

Bone->normal composition but reduced in quantityCortex->thinnedCancellous bone :

More marrow spaces Thin trabeculae

Jaws->in edentulous pt: mand being reduced to a thinfragile strip (Enhanced atrophy of the mandible)

Increased osteoclastic activity throughout skeletonFibrosis of marrow (osteitis fibrosa)Focal areas of bone reorption result in->brown tumorsBrown tumors : (> in mandible)

Identical to other giant cell lesions of the jawsLarge # of multineucleated, osteoclast-like giantcells scattered in highly cellular,vascular fibroblastic C.T stroma.

Hemosiderin->brown colourOccur in relation of periosteum (rare n represent clinically on gingiva similar to giant cellepulis-peripheral giant cell granuloma)

8/3/2019 Metabolic and Endocrine Disorder of Bone

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Radiographic Bone->Increased radiolucencyCortex->thinned

No detectable changes / generalized osteoporosisPartial loss of lamina dura around roots of teeth (not a constant feature)Brown tumors->sharply defined, round/oval radiolucent area, may appear multilocular

Extra info Normal bone->constant turnoverAdult->bone loss gradually predominates over bone

appositionRisk factor 4 periodntal disease(little evidence)

Fuctions of parathyroid hormone :Intestinal absorption of calciumReabsorption of calcium by renal tubulesBone resorption by osteoclast

Excessive hormone :HypercalcemiaHypercalciuriaMetastatic calcification in urinary tract, bd.vessel walls, lungs