Transcript Metabolic Bone disease

Metabolic Bone disease
Tanya Potter
Consultant Rheumatologist
Aims and Objectives
• Aims
– Understand the definition and spectrum of
metabolic bone diseases
• Objectives
– demonstrate understanding of epidemiology,
aetiology, clinical features and management
of osteoporosis, osteomalacia, Paget’s
disease and renal osteodystrophy
Case 1
•
•
•
•
•
•
•
72 year old lady
Acute onset severe thoracic pain
Keeping her awake at night
Radiates around ribs
No history of trauma
PMH – COPD
DH - Inhalers
• What other questions would you ask?
Case 1 - contd
• On examination –
– Frail lady
– Apyrexial
– Thoracic kyphosis
– Tender over spinous processes T7/8
– No neurological deficit
– differential diagnosis?
Diff. Diagnosis of Back Pain
• Simple mechanical eg ligamentous strain
• Degenerative disease with/without neural, cord
or canal compromise
• Metabolic – osteoporosis, Pagets
• Inflammatory – Ankylosing spondylitis
• Infective – bacterial and TB
• Neoplastic
• Others, (trauma,congenital)
• Visceral
Case 1
•
•
•
•
•
Investigations
HB 12.9, WCC 9.0, Plts 245
Na 139, K 4.4, U 7.3, Cr 96
AP 297, ALT 32, Bil 13, Ca 2.41
CRP 8
Osteoporosis
Reduction in bone mass leading to increase risk of fracture
Ratio of mineralised bone: matrix is normal
Imbalance of bone remodelling
• Risk factors for osteoporosis?
• Measurement and definition of OP?
DEXA
T scores
• Typical OP # ?
OP fractures
250,000 # / yr in UK
• Treatment for OP ?
Osteoporosis
• Lifestyle factors
– Falls prevention
– Hip protectors
• Ca and Vit D
•
•
•
•
Bisphosphonates
Strontium
SERMs
Teriparatide- PTH
Preventing steroid induced
osteoporosis
• All: lifestyle advise, calcium and vit D
• Age <65
DEXA- if T score -1.0 or less
then alendronate
• Age >65
alendronate
NICE guidance
• http://guidance.nice.org.uk/TA87/?c=9152
4
• www.sheffield.ac.uk/FRAX/tool
Case 2
• 33 year old Asian lady
• Presents with 3 /12 history of generalised
bony pain
• PMH – depression
• DH – sertraline
• O/E – generalised bony tenderness
• Joints – normal ROM, no inflammation
Investigations
• Hb
• WCC
12.9 (11.5-16.5)
4.7 (4.9-11.0)
Calcium
Phosphate
•
•
•
•
•
253 (150-400)
12
Normal
4.2 (3.0-6.5)
85 (35-120)
Albumin
Alk Phos
Total protein
LFTs
Plt
ESR
Clotting
Urea
Creat
2.18 (2.2-2.6)
0.79 (0.851.45)
39 (35-50)
172 (25-96)
72 (60-80)
normal
• Diagnosis?
Osteomalacia
• Rickets of adulthood
• Deficiency or resistance to Vit D OR Phosphate
handling problem
• Defective mineralization of bone
• Proximal myopathy, Bony pain, malaise
– Deformities much less common than with rickets
• AP raised, Ca and Vit D low or normal
• PO4 low or normal
Causes of osteomalacia/rickets
• Reduced availability of Vit D
– Diet: oily fish, eggs, breakfast cereals
– Elderly individuals with minimal sun exposure
– Dark skin, skin covering when outside
– Fat malabsorption syndromes
– Kidney failure
– malabsorption
• malabsorption
– Coeliac
– Intestinal bypass
– Gastrectomy
– Chronic pancreatitis
– Pbc
• Epilepsy: phenytoin, phenobarbitones
• Genetic disease
• Defective metabolism of Vitamin D
– Chronic renal failure, Vit D dependent rickets,
– Liver failure, anticonvulsants
• Receptor Defects
• Altered phosphate homeostasis
– Malabsorption, RTA, hypophosphatasia (rare,
low levels of alk phos)
Loosers zones
Treatment
• Vitamin D –usually oral
• Calcium supplements
Case 3
• 62 year old lady referred with generalised
muscular pain
• PMH – hypertension
• DH – bendrofluazide
• Examination – largely unremarkable
• Routine bloods all normal except Calcium of
2.95
• She has come back to clinic for results
• What would you do now?
Symptoms of hypercalcaemia
• Stones,
• Bones,
• Moans,
• Psychic Groans
An approach to hypercalcaemia
• Stones, Renal colic
• Bones, Joint, bone, muscle pain, Muscle weakness
• Moans, Constipation Abdominal pains
• Psychic Groans Depression, confusion, altered mental
state, Fatigue, lethargy
• Dehydration, polyuria
Causes of Hypercalcaemia
•
•
•
•
•
•
Malignancy
Hyperparathyroidism – primary or tertiary
Increased intake
Myeloma
Sarcoid
Adrenal failure
Treatment of acute hypercalcaemia
• Hydration, IV if Ca very high
• Bisphosphonates
• Treat cause
Hyperparathyroidism
• Primary hyperparathyroidism:
– Often an incidental finding
– May be part of MEN I, MEN II
• Secondary hyperparathyroidism
– Compensates for chronic low Ca eg. Renal failure or malabsorption
– [Ca2+] and [PO42-] normal PTH high
• Tertiary hyperparathyroidism
– Hyperplasia in longstanding secondary disease
Multiple endocrine neoplasia
• Aut dom
• MEN 1 parathyroid tumours, ant pituitary,
pancreas
• MEN 2A thyroid tumour,
phaeochromocytomas, parathyroid
hyperplasia
• MEN 2B thyroid tumours and phaeos
Renal Osteodystrophy
• Effect on bone of disordered calcium
homeostasis
• May be osteomalacia, hyperparathyroidism
• Leads to
–
–
–
–
–
Bone pain
Skeletal deformity
Muscular weakness
Ectopic calcification
Growth retardation
Hypoparathyroidism
Causes
• Destruction of gland- surgical
(thyroidectomy- may be transient)
• Autoimmune- polyglandular autoimmune
glandular syndrome
• Irradiation or infiltration (cancer, wilsons)
• Abnormal gland development
Case 4
This 73 year old
lady was referred
from her GP to
ENT with
deafness.
They asked her to
see the
rheumatologist
Why?
Paget’s Disease
• Disease of bone remodeling
• Accelerated bone resorption and formation
• Disorganised mosaic pattern bone with increased
vascularity and fibrosis
• Cause unknown
– paramyxovirus, canine distemper
– Genetics- susceptibility loci
• More common in caucasian
• M:F ratio 3:2
10% in over 70’s
Paget’s Disease: clinical manifestations
• Bone pain
• Joint pain
• Deformity
• Spontaneous fractures
Pagets Disease: complications
• Fractures
• Deafness
• Nerve entrapment
• Spinal stenosis
• Cardiac failure
• Osteogenic sarcoma
• Hypercalcaemia (only if immobilized)
Paget’s Disease: investigations
• Raised serum alk phos
• Urinary hydroxyproline, pyridinoline cross-links
• Radiology
– cortical thickening
– osteolytic, osteosclerotic and mixed lesions
– osteoporosis circumscripta
– bone scan
Normal
Paget’s Treatment
• Bisphosphonates
– calcitonin
• Indicated if
– Complications
– Pain
– Deformity
– AP 2-3X Upper limit
– Skull disease
Questions?