Rheumatology Flashcards
Most abundant protein of bone is?
Type 1 collagen
Bone mineral composed of?
Ca and PO4 crystal : hydroxyapetite
Over mineralisation occurs in
- Osteogenesis imperfecta
- Long term bisphosphonate therapy
After how many days osteoclast undergoes apoptosis?
10 days
Markers of bone formation and resorption?
Propeptide fragments for bone formation and pyridinium molecules for bone resorption
Which enzyme is responsible for bone mineralisation?
ALP
Produced by osteoblast degrades pyrophosphate an inhibitor of mineralisation thus enhanced mineralisation of bone
Factor responsible for PO4 homeostasis?
FGF-23
Produced by osteoclast act on kidney promote PO4 excreation
Factor stimulate bone formation
→ Wnt
→ thyroid hormone
→ PTH
Factor stimulates bone resorption?
→ RANKL
→ PTH
→ Thyroid Hormone
Factor inhibit bone resorption
→ Osteoprotagerin
→ Oestrogen
Factors inhibit bone formation?
→ Sclerostin
→ Glucocorticoid
What changes occur in articular cartilage with ageing?
+ ↓ chondroitin sulphate
+ ↑ Keratan sulphate
+ ↓ Water content and shock absorbing properties
What changes occur in articular cartilage in OA?
+ Abnormal chondrocyte divisions
+ Loss of proteoglycan from matrix
+ ↑ Water content
Menisci of the knee get nutrition from?
SF
Which cell secretes SF?
Type B synoviocytes
What is the first line investigation in acute mono arthritis?
Joint Aspiration
Examples of synovial joints are
+ Most limb joint
+ TMJ
+ Costovertebral
Turbid Fluid with high neutrophil count found in
+ Septic arthritis
+ Reactive arthritis
+ Crystal arthritis
Uniform blood staining on synovial fluid causes due to
Bleeding diathesis
Trauma
Pigmented villonodular synovitis
Severe inflammatory synovitis
Features of urate crystal
Diagnostic of Gout
Long and needle shaped
Strong light intensity
Negative birefringence
Radiological features of Rheumatoid arthritis
- Periarticular osteoporosis
- Joint space narrowing
- Joint sublaxation
- Marginal joint erosion
Radiological Features of OA
Osteophyte
Joint space narrowing (focal)
Subchondral cyst
Subchondral Sclerosis
Joint Deformity
Calcified loose bodies over synovium
Radionuclide bone scintigraphy used mainly in Dx of?
Metastatic bone disease
Paget’s disease
What is used in radionuclide bone scintigraphy?
TC labelled bisphosphonate
DXA is used in?
Dx and Mx of osteoporosis
What causes high BMD in presence of osteoporosis
Aortic calcification
Vertebral fractures
Degenerative disc disease
OA
What are the causes of elevated CPK (creatinine phosphokinase)
Inflammatory myositis, vasculitis
MND
Muscular Dystrophy
MI, trauma
Alcohol, drug, statins
Hypothyroidism
Viral myositis
Causes normal CRP with High ESR
SS UP HOME
S- SLE
S- Systemic sclerosis
U- Ulcerative Colitis
P- Pregnancy
H- Heart failure
O- Old Age
M- Multiple Myeloma
E- ESRD
Antibodies associated with SLE
- Anti La Ab (Anti-SSB)
- Anti Ro Ab (Anti-SSA)
- Anti Sm Ab (Anti- Smith)
- Anti ribonucleoprotein Ab ( Anti RNP)
Ab responsible for mixed connective tissue disease?
Anti- RNP
Ab responsible for systemic sclerosis
- Anti RNA polymerase
- Anti Scl-70 (anti+tropoisomerase I ab)
- Anti centromere ab ( Cutaneous)
Ab responsible for Dermatomyositis and polymyositis
Anti Jo 1 ab ( anti histidyle tRNA synthetase)
What are the diagnostic triads in inflammatory myositis and suspected myopathy on Electromyography
★Spontaneous fibrillation
★Short duration AP in polyphasic disorganized outline
★Repetitive bouts of high voltage oscillation on needle contact with diseased muscle
Causes of monoarthritis
Gout
Pseudogout
Trauma
Haemarthrosis
Spondyloarthritis
Psoriatic arthritis
Reactive arthritis
Enteropathic arthritis
Acute pain with, young men, 1st MTP involvement, needle shaped negative birefringence crystal with H/O taking Anti TB drugs/ Diuretics / Alcohol
Gout
Acute onset with H/O diarrhoea or genital infection
Reactive arthritis
Acute onset, older woman with pre existing OA
Pseudogout
Acute onset with red, hot swollen joints with skin erythema + fever + H/O DM, Immunosuppression, RA, I/V drug misuse what is the dx and Mx
Septic arthritis
I/V antibiotic should be given promptly
Following injury large joint effusion
Hemarthosis
Investigation of choice for acute monoarthritis
Joint aspiration
Old age + gradual onset (usually knee)
OA
Common cause of Polyarthritis
Rheumatoid arthritis
Viral arthritis
Osteoarthritis
SLE
Psoriatic arthritis
Enteropathic arthritis
Axial Spondyloarthritis
Chronic Gout
Chronic sarcoidosis
CPA
Poncet’s Disease
JIA
Hallmark of inflammatory polyarthritis
★ Morning Stiffness
★ Worsening of symptoms with inactivity
★ Synovial tenderness and swelling
Which joints involved in psoriatic arthritis
PIP, DIP Sacroilitis and other large joints
Which joints involved in Rheumatoid arthritis
MCP, PIP, MTP, other small and large joints of both upper and lower limb
Features of psoriatic arthritis
Asymmetrical
Joints involved : PIP, DIP Sacroilitis, large and small joint
Nail pitting / Onycholysis
Dactylitis / Enthesitis
Features of Osteoarthritis
Symmetrical
Joint involved: PIP, DIP, 1stCMP, hip, knee and spine
Heberden’s and boucher’s node
Causes of reynaud’s phenomenon
Systemic sclerosis, Anti phospholipid syndrome, SLE, Sjogren syndrome
Causes of pathological fractures
★ Malignancy
★ Paget’s Disease
★ Osteomalacia
Features of mechanical low back pain
★ Pain varies e physical activity (improved with rest)
★ Onset often sudden and precipitated by lifting or bending
★ Recurrent episodes
★Pain limited to back or upper leg
★No clear nerve root distribution
★ No systemic features
★ Self limiting with recovery at 6 weeks in 90%
Red flags for possible spinal pathology
≈History
★ Age >55 years and <20 years
★ Constant progressive pain unrelived by rest
★ thoracic pain
★Ca, HIV, TB, Systemic glucocorticoid use, osteoporosis
★Systemic upset, sweat, weight loss
★Major trauma
≈Examination
★Spinal deformity
★ Saddle anaesthesia
★ Progressive neurological sign / muscle wasting
★ Multiple levels of root sign
Endocrine causes of proximal muscle weakness
Hypothyroidism
Hyperthyroidism
Addison’s disease
Cushing Syndrome
Inflammatory causes of proximal muscle weakness
Polymyositis
Dermatomyositis
Inclusion body myositis
Sarcoid
Myasthenia gravis
Other autoimmune connective tissue disease
Metabolic causes of proximal muscle weakness
Myophosphorylase deficiency
Carnitine deficiency
Phosphofructokinase deficiency
Hypokalemia
Osteomalacia
Hypercalcemia
What are the drugs responsible for proximal muscle weakness
Alcohol
Cocaine
Glucocorticoid
Statins and fibrate
Zidovudine
TNF inhibitors
Features of cauda equina syndrome
- Difficulty with micturition
- Loss of anal sphincter tone or fecal incontinence
- Saddle anaesthesia
- Gait Disturbance
- Pain, numbness or weakness affecting one or both legs
Where Cox-1 enzyme is expressed
Gastric mucosa → protect against mucosal damage
Platelet → regulate platelet aggregation
Kidneys → regulate renal blood flow
Site of cox 2
Induced at the site of inflammation producing pg that causes local pain and swelling
Which has the highest risk among NSAIDS of GI bleeding and perforation?
Indometacin
Which has the lowest risk among NSAIDS of GI bleeding and perforation?
Celecoxib
Etoricoxib
What is the most important risk factor for NSAIDS induced GI bleeding and perforation? (Peptic ulcer)
Age>60 yrs
Past history of PUD
Vision monitoring is required for which drug?
Hydroxychloroquine
Bp monitoring is required for which drug?
Leflunomide
Ciclosporin A
GFR measurements are required for
Cyclophosphamide
Ciclosporin A
Which drug isn’t required FBC and LFT monitoring
Hydroxychloroquine
Ciclosporin A
Targeted sDMARD except tofacitinib
Trigger finger
Result if stenosing tenosynovitis in the flexor tendon sheath e intermittent locking of finger in flexion
Cause:
- Spontaneous
- RA
Mx: Glucocorticoid injection
Spondylolysis
Break in the integrity of vertebral neural arch
Principal cause: Acquired defect in the pars interarticularis due to a fracture
Commonly seen in: Gymnasts, dancers, runners
Spondylolisthesis
A defect causes slippage of a vertebra one blow
Scoliosis
Abnormal lateral curvature of spine more than 10 degrees
Cause:
+ Idiopathic
+ Neuromuscular disorder such as muscular dystrophy, cerebral palsy, neurfibromatosis
+ Marfan Syndrome
Carpal Tunnel Syndrome
Caused by compression of the median nerve at the wrist
Common cause:
Hypothyroidism
DM
RA
Obesity
Pg (3rd trimester)
Site of involvement of following Disease
1. Diabetic neuropathy
2. Syringomyelia
3. Leprosy
4. Tabes dorsalis
- Hind foot
- Shoulder, elbow, wrist
- Hands and Feet
- Knees, spine
Hypertrophic pulmonary osteoarthropathy
Characterised by clubbing and painful swelling of limbs, periosteal new bone formation and arthralgia / arthritis
Most Common cause
Bronchial carcinoma
Mesothelioma
Tumours that most commonly metastasise to bone are
+ Myeloma
+ Bronchus
+ Breast
+ Thyroid
+ Kidney
+ Prostate
What is the most common primary bone tumour
Osteosarcoma
Osteosarcoma
Most common primary bone tumour
Age: Under 30
Presentation : Local pain and Swelling
X-ray: Expansion of bone with surrounding soft tissue mass, often containing island of calcification
Osteogenesis imperfecta
Group of disorders characterised by severe osteoporosis and multiple fractures in childhood
Caused by mutation in COL1A1 and COL1A2 genes which encode proteins that make Type 1 collagen
Osteonecrosis
Death of bone due to impairment of blood supply
Common site of Osteonecrosis
Femoral head, Humeral head, Navicular and Scaphoid
Osteonecrosis associated with
Direct trauma
Thrombophilia
Antiphospholipid syndrome
Gaucher’s disease
Hemoglobinopathies such as sickle cell disease
Predisposing factors:
High dose Glucocorticoid treatment
Alcohol excess
SLE
HIV
Radiotherapy
X-ray findings of Osteonecrosis
Normal in early stages but later may show evidence of osteosclerosis and deformity of affected bone
Confirmatory investigation for Osteonecrosis
MRI
What are the characteristics of deformity in RA?
Ulnar deviation of finger
Swan neck deformity
Boutonniere or button hole deformity
Z deformity of the thumb
Dorsal subluxation of ulna at distal radio ulnar joint
Triggering finger
Subluxation of the MTP joint of foot (Cock-up toe)
In hind foot: Valgus deformity
Flat foot
Nerve involved in peripheral neuropathy of RA
Median nerve
Ulnar nerve at wrist and elbow
Lateral popliteal nerve at head of fibula
Posterior tibial nerve (tarsal tunnel syndrome)
