Metabolic Bone Disease Flashcards
What is Paget’s Disease of bone?
Increased bone resorption followed by increased bone formation localised to areas such as the skull and long bones
Leads to disorganised bone: bigger, less compact, more vascular and more susceptible to deformity and fracture
What are the risk factors for Paget’s disease?
Family history-strong genetic factor Age over 50 Environmental factors such as arsenic levels Chronic Viral infections Geographical correlation
What are the symptoms of Paget’s disease?
Asymptomatic Long bone or back pain (deep seated pulsing pain) Prognathism (increased jaw) Frontal bossing Heat over Paget's bone Neuro problems such as hearing loss or loss in visual acuity Facial Pain Problems with dentition Osteosarcoma risk
What investigations should be carried out in Paget’s disease?
Plain x-ray Bone scan Total serum alkaline phosphatase Bone-specific alkaline phosphatase Serum calcium Serum procollagen 1 N-terminal peptide (P1NP) Serum C-terminal propeptide of type 1 collagen (CTX) LFTs Serum 25-hydroxyvitamin D CT Bone Biopsy
What is the management for Paget’s disease?
Do not need treatment if asymptomatic unless need to do surgery over that area (due to highly vascular bone), if affects skull or the bone is deformed.
Treat with IV bisphosphonate- zoledronic acid
Or treat with calcitonin
What are rickets and osteomalacia?
Severe nutritional vitamin D or Calcium deficiency causes insufficient mineralisation and thus rickets in a growing child and Osteomalacia in the adult when the epiphyseal lines are closed
What are the signs and symptoms of rickets?
Bone pain Growth retardation Delayed achievement of motor milestones Bony deformities Muscle weakness Carpopedal spasm Numbness or paraesthesia Tetany Hypocalcaemic seizures Large forehead Wide joints at wrists and ankles
What are the signs and symptoms of osteomalacia?
Fractures Malabsorption syndromes Diffuse bone pain and tenderness Proximal muscle weakness Family history of osteomalacia Waddling gait
What investigations should be done for rickets and osteomalacia?
Serum calcium level Serum 25-hydroxyvitamin D level Serum phosphate level Serum urea and creatinine Intact PTH Serum alkaline phosphatase 24-hour urinary calcium Calcitriol levels Bone x-rays 24-hour urinary phosphate DXA Iliac crest biopsy with double tetracycline labelling
What is osteogenesis imperfecta?
Genetic disorder of connective tissue characterised by fragile bones from mild trauma and even acts of daily life
Defects in type 1 collagen
28 types
What are the first four most common types of osteogenesis imperfecta?
Type 1: milder form-when child starts to walk and can present in adults
Type 11: lethal by age 1
Type 111: progressive deforming with severe bone dysplasia and poor growth
Type 1V : similar to type 1 but more severe
What are the signs and symptoms of osteogenesis imperfecta?
Growth deficiency Defective tooth formation (dentigenesis imperfecta) Hearing loss Blue sclera Scoliosis Barrel chest Ligamentous laxity Easy bruising
What scoring system is used to assess hypermobility?
Beighton score
If score five or over out of nine then classed as hypermobile
What is the definition of osteoporosis?
Osteoporosis is a complex skeletal disease characterised by low bone density and micro-architectural defects in bone tissue, resulting in increased bone fragility and susceptibility to fracture.
Why are women more likely to get osteoporosis than men?
During menopause there is an increase in bone loss so older women are extremely likely to be osteoporotic
What are the risk factors for osteoporosis?
Older age, female sex, white ancestry, low body mass index, family history of maternal hip fracture, post menopause, glucocorticoid use, prior fracture, hypogonadism, loss of height, secondary amenorrhoea, smoking, excessive alcohol use, prolonged immobilisation, vitamin D deficiency, hyperthyroidism, weight loss of >10% of body weight, androgen deprivation treatment (in men), aromatase inhibitor treatment (in women), tobacco use, heparin use, anticonvulsant use, or kidney stone disease.
What are the symptoms of osteoporosis?
Back pain Kyphosis Impaired vision Impaired gait, imbalance, and lower-extremity weakness Vertebral tenderness
What are the endocrine causes of osteoporosis?
Thyrotoxicosis Hyper and hypoparathyroidism Cushing's Hyperprolactinaemia Hypopituitarism Early menopause
What are the rheumatic causes of osteoporosis?
Rheumatoid arthritis
Ankylosing spondylitis
Polymyalgia rheumatica
What are the GI causes of osteoporosis?
Inflammatory diseases: UC and Crohn’s
Liver diseases: PBC, CAH, Alcoholic cirrhosis, Viral cirrhosis( hep C)
Malabsorption: chronic pancreatitis, coeliac disease, whipples disease, short gut syndromes and ischaemic bowel
What are some medications that can cause osteoporosis?
Steroids PPI Enzyme inducting antiepileptic medications Aromatase inhibitors GnRH inhibitors Warfarin
What are investigations that should be carried out for osteoporosis?
Dual-energy x-ray absorptiometry (DEXA) Quantitative ultrasound (QUS) of the heel X-ray (wrist, heel, spine, and hip) Quantitative CT Serum alkaline phosphatase Serum calcium Serum albumin Serum creatinine Serum phosphate Serum 25-hydroxy vitamin D Serum parathyroid hormone Thyroid function tests Urinary free cortisol Serum testosterone (men) Urine protein electrophoresis Serum protein electrophoresis
What are the T and Z scores for DEXA bone scanning in osteoporosis?
T score-comparing patients score with that of someone with their exact variables but at 30 years old
Z score-compares patient to peer group with exact same variables. If Z score is abnormal then need to investigate reason for osteoporosis
What medications can be used in osteoporosis?
HRT reduces chance of all fractures
Selective Oestrogen Receptor Modulator such as tamoxifen have no effect on vertebral fracture rate
Bisphosphonates
Monoclonal antibody like Denosumab reduces osteoclastic bone resorption
Teriparatide causes bone growth
