Musculoskeletal Flashcards
Define amyloidosis.
Heterogenous group of diseases characterized by extracellular deposition of amyloid fibrils.
Can be systemic or localised - e.g. pancreatic islets of Langerhans, cerebral cortex, cerebral blood vessels, bones and joints
Pancreatic Islets of Langerhans - T2DM
Cerebral Cortex - Alzheimer’s
Cerebral Blood Vessels - amyloid angiopathy
Bones & Joints - long-term dialysis caused by B2 microglobulin
Explain the aetiology / risk factors of amyloidosis.
Amyloid fibrils are polymers comprising low-molecular-weight subunit proteins.
Amyloid fibril subunits are derived from proteins that undergo conformational changes to adopt anti-parallel B-pleated sheet configuration.
Amyloid fibril subunits associated with GAGs and serum amyloid P-component (SAP), and their sdeposition progressively disrupts the structure and function of nromal tissue.
Classification:
- AA - serum amyloid A protein - e.g. Chronic inflammatory (RA, seronegative arthritides, Crohn’s, familial Mediterranean fever), chronic infections (TB, bronchiectasis, osteomyelitis), malignancy (Hodgkin’s disease, renal cancer)
- AL - monoclonal immunoglobulin light chains fibril protein - e.g. subtle monoclonal plasma cell dyscrasias, multiple myeloma, Waldenstrom’s macroglobulinaemia, B-cell lymphoma
- ATTR (familiar amyloid polyneuropath) - genetic-variant transthyretin - autosomal dominantly transmitted muttaions in the gene for transthyretin (TTR), variable penetrance
Risk factors:
- Monoclonal gammopathy of undetermined significance (MGUS)
- Inflammatory polyarthropathy
- Chronic infections
- IBD
Summarise the epidemiology of amyloidosis.
AA = 1-5% incidence among patients with chronic inflammatory disease
AL = estimated annual incidence of about 3,000 cases in US, 300-600 cases in UK
Hereditary - 5% of patients with systemic amyloidosis
Recognise the presenting symptoms of amyloidosis.
Renal
- Proteinuria
- Nephrotic syndrome
- Renal failure
Cardiac
- Restrictive cardiomyopathy
- Heart failure
- Arrythmia
- Angina - due to accumulation of amyloid in coronary arteries
GI
- Macroglossia - characteristic of AL
- Hepatomegaly
- Splenomegaly
- Gut dysmotility
- Malabsorption
- Bleeding
Neurological
- Sensory and motor neuropathy
- Autonomic neuropathy - symptoms of bowel or bladder dysfunction, postural hypotension
- Carpal tunnel syndrome
Skin
- Waxy skin
- Easy brusing
- Purpura around the eyes - characteristic of AL
- Plaques
- Nodules
Joints
- Painful asymmetrical large joint
- Shoulder pad sign - enlargement of the anterior shoulder
Haematological
- Bleeding diathesis - factor X deficiency due to binding on amyloid fibrils primarily in the liver and spleen and reduce synthesis of coagulation factors in patients with advanced liver disease
Recognise the signs of amyloidosis on physical examination.
Renal
- Proteinuria
- Nephrotic syndrome
- Renal failure
Cardiac
- Restrictive cardiomyopathy
- Heart failure
- Arrythmia
- Angina - due to accumulation of amyloid in coronary arteries
GI
- Macroglossia - characteristic of AL
- Hepatomegaly
- Splenomegaly
- Gut dysmotility
- Malabsorption
- Bleeding
Neurological
- Sensory and motor neuropathy
- Autonomic neuropathy - symptoms of bowel or bladder dysfunction, postural hypotension
- Carpal tunnel syndrome
Skin
- Waxy skin
- Easy brusing
- Purpura around the eyes - characteristic of AL
- Plaques
- Nodules
Joints
- Painful asymmetrical large joint
- Shoulder pad sign - enlargement of the anterior shoulder
Haematological
- Bleeding diathesis - factor X deficiency due to binding on amyloid fibrils primarily in the liver and spleen and reduce synthesis of coagulation factors in patients with advanced liver disease
Identify appropriate investigations for amyloidosis and interpret the results.
- Tissue biopsy - congo red stain, immunohistochemistry (diagnose amyloidosis, identify amyloid fibril protein)
- Urine (proteinuria, free immunoglobi light chains in AL)
- Blood (CRP, ESR, RF, Ig levels, serum protein electrophoresis, LFTs, U&E, SAA levels)
- 123I-SAP Scan - radiolabeled SAP localizes to the deposits enabling quantitative imaging of amyloidotic organs throughout the body
Define osteomyelitis.
An inflammatory condition of bone caused by an infecting organism, most commonly Staphylococcus aureus.
Explain the aetiology / risk factors of osteomyelitis.
Usually involves single bone, but rarely affects multiple sites.
Occurs in peripheral or axial skeleton.
Stage on the aetiology of infection, pathogenesis, extent of bone involvement, duration and host factors particular to the individual patients.
Either haematogenous or contigous-focus.
Risk factors:
- Previous osteomyelitis
- Penetrating injury
- IV drug misuse
- Diabetes
- HIV infection
- Recent surgery
- Distant or local infections
- Sickle cell anaemia
- RA
- CKD
- Immunocompromising conditions
- URTI
- Varicella infection
Summarise the epidemiology of osteomyelitis.
The annual incidence of osteomyelitis was less than eleven cases per 100,000 person-years until the sixth decade of life. Thereafter, incidence rates increased steeply with age, corresponding to a roughly 50% increase in incidence per decade of life.
Recognise the presenting symptoms of osteomyelitis.
- Risk factors
- Limp or reluctance to weight-bear
- Non-specific pain at site of infection
- Malaise and fatigue
- Local back pain associated with systemic symptoms
- Paravertebral muscle tenderness and spasm
- Local inflammation, tenderness, erythema or swelling
- Fever
- Spinal cord or nerve root compression
- Wound drainage, acute or old healed sinuses
- Scars, previous flaps, fracture fixation
- Reduced range of movement
- Reduced sensation in diabetic foot infection
- UTI symptoms
- Torticollis
- Skin or other infections, recent episodes of Staphylococcus aureus bloodstream infection, indwelling catheter
- Limb deformity
- Tenderness to percussion
- Meningitis
Recognise the signs of osteomyelitis on physical examination.
- Risk factors
- Limp or reluctance to weight-bear
- Non-specific pain at site of infection
- Malaise and fatigue
- Local back pain associated with systemic symptoms
- Paravertebral muscle tenderness and spasm
- Local inflammation, tenderness, erythema or swelling
- Fever
- Spinal cord or nerve root compression
- Wound drainage, acute or old healed sinuses
- Scars, previous flaps, fracture fixation
- Reduced range of movement
- Reduced sensation in diabetic foot infection
- UTI symptoms
- Torticollis
- Skin or other infections, recent episodes of Staphylococcus aureus bloodstream infection, indwelling catheter
- Limb deformity
- Tenderness to percussion
- Meningitis
Identify appropriate investigations for osteomyelitis and interpret the results.
1st Line:
- FBC - HIGH WCC
- ESR - HIGH
- CRP - HIGH
- Blood culture - may be positive, indicating infecting organism and microbial sensitivities
- Plain XR of affected area
Results of XR - ACUTE DISEASE
- Initially normal
- Osteopenia 6-7 days after infection onset
- Evidence of bone destruction, cortical breaches and periosteal reaction
- Involucra and sequestra sometimes seen
- Diffuse osteopenia developing later due to disuse of affected limb
- Joint effusion in local joints
Results of XR - DISCITIS
- Lacteral spin radiographs show late changes at 2-3 weeks into illness
- Decreased intervertebral space
- Erosion of vertebral plate
Results of XR - VERTEBRAL OSTEOMYELITIS:
- Localised rarefication (thinning) of vertebral body
- Anterior bone destruction later on
Results of XR - CHRONIC DISEASE
- Intramedullary scalloping
- Cavities
- Cloacae seen
- Fallen leaf sign when a piece of endosteal sequestrum detached and fallen into medullary canal
Consider:
- Bone samples and bone biopsy - positive, other pathology shown
- PCR
- MALDI-TOF mass spectrometry - match reference strains
- Swabs
- Urine microscopy, culture and sensitivities
- Histology 0 infecting organisms, acute or chronic inflammatory cells, dead bone, active bone resorption, small sequestra, malignancy
- Probe-to-bone test - may reach bone, rule in osteomyelitis in high-risk patient with diabetes
- Bone MRI - high signal on T2 images, fat suppression sequences, changes in children within 3-5 days of onset, vertebral bone changes
- US - collections, subperiosteal abscesses, adjacent joint infusions
- CT scan - bone destruction, sequestra, abscess
- Radionuclide scan - increased uptake of radioactive injectate in infected sites
- Bone scintigraphy - hot spots of infection, positive 24hrs after onset
- Echocardiogram - valvular vegetations
- CXR - show primary or reatcive TB
- Mantoux test - positive for Mycobacteruim TB
Define septic arthrtis.
The infection of 1 or more joints caused by pathogenic inoculation of microbes.
Occurs either by direct inoculation or haematogenous spread.
Explain the aetiology / risk factors of septic arthritis.
Regard a hot, swollen, acutely painful joint with restriction of movement as septic arthritis until proven otherwise, even in the absence of fever and irrespective of microbiology and blood test results.
Risk factors:
- Underlying joint disease
- Prosthetic joint
- Age
- Immunosuppression
- Contiguous spread
- Exposure to ticks
- Previous intra-articular corticosteroid injection
- Recent joint surgery
- Low socioeconomic status
Summarise the epidemiology of septic arthritis.
The estimated incidence of septic arthritis in developed countries is 6 cases per 100,000 population per year.
In patients with underlying joint disease or with prosthetic joints the incidence increases approximately 10-fold, to 70 cases per 100,000 of the population.
Recognise the presenting symptoms of septic arthritis.
- Hot
- Swollen
- Painful
- Restricted
- Acute presentation
- Fever
- Large joint
- Prosthetic joint
- Single joint affected
- Symptoms are out of proportion to elsewhere disease activitiy
- Sexual activity - gonoccocal septic arthritis may present with polyarthralgia localising over one joint, fever, chills and skin lesions
- Erythema migrans
- Risk factors present
Recognise the signs of septic arthritis on physical examination.
- Hot
- Swollen
- Painful
- Restricted
- Acute presentation
- Fever
- Large joint
- Prosthetic joint
- Single joint affected
- Symptoms are out of proportion to elsewhere disease activitiy
- Sexual activity - gonoccocal septic arthritis may present with polyarthralgia localising over one joint, fever, chills and skin lesions
- Erythema migrans
- Risk factors present
Identify appropriate investigations for septic arthritis and interpret the results.
1st Line:
- Synovial fluid microscopy, Gram stain and polarising microscopy - ?micro-organisms, urate or pyrophosphate crystals
- Synovial fluid culture and sensitivities
- Synovial fluid WCC
- Blood culture and sensitivities
- WCC - elevated
- ESR - elevated
- CRP - elevated
- U&E - assess for sepsis and end-organ damage
- LFTs - assess for sepsis and end-organ damage
- Plain X-Ray - reveals degenerative changes or chondrocalcinosis (not diagnostic for septic arthritis)
- USS - presence of effusion to guide aspiration
Consider:
- Procalcitonin (PCT) - raised >0.5ng/mL more specific marker for bacterial infection than CRP, ESR or WCC
- MRI - ?associated osteomyelitis
- PCR
- Swabs for microscopy, culture and sensitivity
- Urine dipstick - organisms on microscopy, WCC, blood
- ELISA
- Synovial biopsy - ? myobacterium tuberculosis, fungi
- Calprotectin - high
Define Sjogren’s Syndrome.
A systemic auto-immune disorder, characterised by keratoconjunctivitis sicca and xerostomia as a consequences of lymphocytic infiltration into the lacrimal salivary glands.
Explain the aetiology / risk factors of Sjogren’s Syndrome.
Primary - occurs alone
Secondary - occurs along with another auto-immune disease - e.g. lupus, RA, systemic sclerosis
Risk factors:
- Female
- SLE
- RA
- Systemic sclerosis (scleroderma)
- HLA Class I markers
- Age peaks in 20-30s and after menopause
- Genetic inheritance
Summarise the epidemiology of Sjogren’s Syndrome.
Sjogren syndrome is far from a rare disorder with an incidence approaching approximately one-half of that of rheumatoid arthritis (RA) or affecting 0.5% to 1.0% of the population. Between 400,000 and 3.1 million adults have Sjögren’s syndrome.
Recognise the presenting symptoms of Sjogren’s Syndrome.
- Dry eyes - keratoconjunctivitis sicca
- Dry mount - xerostomia
- Dryness of skin, nose, throat, vagina
- Arthralgias
- Myalgias
- Peripheral neuropathies
- Lymphoma
- Fatigue
- Vasculitis
- Dental caries
- Increased oral fungal and bacterial infections
- Arthritis
- Kidney disease
- Corneal ulceration
- No salvia pool
- Enlarged salivary glands
- Facial pain
- Burning mouth syndrome
- History of VTE
- History of AA or dissection
Recognise the signs of Sjogren’s Syndrome on physical examination.
- Dry eyes - keratoconjunctivitis sicca
- Dry mount - xerostomia
- Dryness of skin, nose, throat, vagina
- Arthralgias
- Myalgias
- Peripheral neuropathies
- Lymphoma
- Fatigue
- Vasculitis
- Dental caries
- Increased oral fungal and bacterial infections
- Arthritis
- Kidney disease
- Corneal ulceration
- No salvia pool
- Enlarged salivary glands
- Facial pain
- Burning mouth syndrome
- History of VTE
- History of AA or dissection
Identify appropriate investigations for Sjogren’s Syndrome and interpret the results.
1st Line:
- Schirmer’s test - positive (filter paper placed in lower conjunctival sac, less than 5mm of paper is wetted after 5 mins)
- Anti-60 kD (SS-A) Ro and anti-La (SS-B) - positive
Consider:
- Sialometry - decreased
- Minor salivary gland biopsy - focus score 1 or greater
- Lissamine green test - score of 3 or more
- Fluorescein corneal staining test - score of 3 or more
- Parotid sialography - gross distortion of the normal pattern of parotid ductules coupled with significant retention of contrast material
- Salivary gland Technetium-99m pertechnetate scintigraphy - decreased uptake and secretion
- Skin biopsy - focal and segmental transmural necrotising inflammation in a medium-sized vessel (i.e., a small or medium-sized artery)
- Angiography - beading, aneurysm, or smooth, tapering vessel stenosi
- Urinalysis - may show abnormal levels of phosphate, calcium, potassium, glucose due to renal tubular acidosis
- Serum electrolytes - may show hypokalaemia with a normal anion gap; hyperchloraemic metabolic acidosis
- MRI salivary glands - inflammation of salivary glands
- US salivary glands - high salivary gland ultrasonography score
Define SLE.
A chronic multi-system disorder that most commonly affects women during their reproductive years.
Explain the aetiology / risk factors of SLE.
- Anti-nuclear antibodies + constitutional symptoms
- Involves skin and joints
- Serositis, nephritis, haematological cytopenias and neurological manifestations
Risk factors:
- Female sex
- Age 15-45 years
- African / Asian descent in Europe and US
- Drugs
- Sun exposure
- Family history of SLE
- Tobacco smoking
Summarise the epidemiology fo SLE.
The reported prevalence of systemic lupus erythematosus (SLE) in the United States is 20 to 150 cases per 100,000 [1-3]. In women, prevalence rates vary from 164 (white) to 406 (African American) per 100,000 [2].
Recognise the presenting symptoms of SLE.
- Malar (butterfly) rash
- Photosensitive rash
- Discoid rash
- Fatigue
- Weight loss
- Fever
- Oral ulcers
- Alopecia
- Arthralgia / artritis
- Fibromyalgia
- Raynaud’s phenomenon
- Chest pain and SOB
- Venous or arterial thrombosis
- Hypertension
- Signs of nephrosis (e.g. oedema)
- Lymphadenopathy
- Abdominal pain, vomiting or diarrhoea
- Nose ulcers
- Poorly localised proximal limb inflammatory pain with weakness
- Dysrhythmias - e.g. tachycardia
- Conduction defects or unexplained cardiomegaly
- CNS signs - seizures, CNS abnormalities, cognitive defects, psychosis
- Dysphagia
Recognise the signs of SLE on physical examination.
- Malar (butterfly) rash
- Photosensitive rash
- Discoid rash
- Fatigue
- Weight loss
- Fever
- Oral ulcers
- Alopecia
- Arthralgia / artritis
- Fibromyalgia
- Raynaud’s phenomenon
- Chest pain and SOB
- Venous or arterial thrombosis
- Hypertension
- Signs of nephrosis (e.g. oedema)
- Lymphadenopathy
- Abdominal pain, vomiting or diarrhoea
- Nose ulcers
- Poorly localised proximal limb inflammatory pain with weakness
- Dysrhythmias - e.g. tachycardia
- Conduction defects or unexplained cardiomegaly
- CNS signs - seizures, CNS abnormalities, cognitive defects, psychosis
- Dysphagia
Identify appropriate investigations for SLE and interpret the results.
1st Line:
- FBC and differential - anaemia, leukopenia, thrombocytopenia, pancytopenia
- Activated PTT - anti-phospholipid antibody patients have prolonged PTT
- U&E - high urea, high creatinine
- ESR and CRP - high
- Anti-nuclear antibodies, dsDNA, Smith antigen - positive
- Urinalysis - haematuria, casts (red cell, granular, tubular or mixed), proteinuria
- CXR - pleural effusion, infiltrates, cardiomegaly
- ECG - exclude other causes
Consider:
- Blood and urine cultures - exclude infection
- Antiphospholipid antibodies - positive
- Coombs test - positive
- 24-hour urine collection for protein or spot urine for protein/creatinine ratio - proteinuria
- Complement levels - complement consumption
- Creatinine phosphokinase - elevated
- Plain XR of affected joints - inflammation, non-erosive arthritis
- Renal USS - exclusion
- Chest CT - lung fibrosis, effusions
- PFT - restrictive pattern
- Pleural aspiration - exudate
- Brain MRI - white matter changes
- Echocardiography - pericarditis, pericardial effusion, pulmonary hypertension
- Skin biopsy - immune deposits at the dermal-epidermal junction on immunofluorescence or non-specific inflammation
- Renal biopsy - immune deposits, mesangial hypercellularity, focal, segmental or global glomerulonephritis
- TSH - exclusion
Define systemic sclerosis.
A multi-system, autoimmune disease, characterised by functional and structural abnormalities of small blood vessels, fibrosis of skin and internal organs, production of autoantibodies.
Explain the aetiology / risk factors of systemic sclerosis.
Unknown.
2 TYPES:
- Limited cutaneous SSc
- Diffuse cutaneous SSc
Limit - less severe internal organ involvement, better prognosis
Risk factors:
- Family history
- Immune dysregulation - e.g. positive ANA
- Exposure to environmental substances and toxins - e.g. silica dust, solvents
Summarise the epidemiology of systemic sclerosis.
Scholarly articles for epidemiology of systemic sclerosis
Epidemiology of systemic sclerosis - Nikpour - Cited by 114
Epidemiology of systemic sclerosis: incidence, … - Barnes - Cited by 310
Epidemiology of systemic sclerosis (scleroderma) - MEDSGER JR - Cited by 343
A 2019 epidemiology study reported that based on 39 publications, the prevalence of systemic sclerosis in Europe and North America was 7.2-33.9 cases per 100,000 individuals, with an annual incidence rate of 0.6-2.3 cases per 100,000 individuals. Systemic sclerosis is rare in the resident population of Japan and China.
Recognise the presenting symptoms of systemic sclerosis.
- Raynaud;’s phenomenon
- Digital pits or ulcers
- Swelling of the hands and feet
- Skin thickening
- Loss of function of hands
- Sclerodactyly
- Heartburn reflux and dysphagia
- Bloating
- Faecal incontinence
- Athralgias and myalgias
- Abnormal nail-fold capillaroscopy
- Telangiectasia
- Subcutaneous calcinosis
- Dyspnoea
- Dry crackles at lung bases
- Tendon friction rub
- Abrupt onset moderate / marked hypertension
- Fatigue
- Dry cough
- Decreased exercise tolerance
- Weight loss
- Inflammatory arthritis
- Proximal muscular weakness (inflammatory myositis)
- Synovitis
- Increased accentuation of the pulmonic component of S2 heart sound
- Signs of anaemia
Recognise the signs of systemic sclerosis on physical examination.
- Raynaud;’s phenomenon
- Digital pits or ulcers
- Swelling of the hands and feet
- Skin thickening
- Loss of function of hands
- Sclerodactyly
- Heartburn reflux and dysphagia
- Bloating
- Faecal incontinence
- Athralgias and myalgias
- Abnormal nail-fold capillaroscopy
- Telangiectasia
- Subcutaneous calcinosis
- Dyspnoea
- Dry crackles at lung bases
- Tendon friction rub
- Abrupt onset moderate / marked hypertension
- Fatigue
- Dry cough
- Decreased exercise tolerance
- Weight loss
- Inflammatory arthritis
- Proximal muscular weakness (inflammatory myositis)
- Synovitis
- Increased accentuation of the pulmonic component of S2 heart sound
- Signs of anaemia
Identify appropriate investigations for systemic sclerosis and interpret the results.
1st Line:
- Serum auto-antibodies - positive ANA
- FBC - microcytic anaemia (GI bleed), microangiopathic haemolytic anaemia (MAHA) in scleroderma renal crisis
- Urea and serum creatinine - high in scleroderma renal crisis
- ESR and CRP - high
- Urine microscopy - proteinuria, cells or casts in scleroderma renal crisis
- Complete PFTs - spirometry, lung volumes and diffusing capacity measurement - interstitial lung disease = low FVC, low DLCO plus restrictive pattern , pulmonary hypertension, disproportionate drop in DLCO compared with FVC
- ECG - cardiac involvement
- Echocardiogram - pulmonary hypertension, rise in RVSP, pericardial effusion, RV or LV diastolic dysfunction present
- CXR- interstitial lung disease (bi-basilar interstitial infiltrates), cardiomegaly, RHF
- Barium swallow - diminished oesophageal peristalsis and gastroparesis, diminished muscle tone in lower oesophagus, reflux of barium, strictures
Consider:
- CT chest - interstitial lung disease (ground glass opacities, thickened interstitium, interstitial fibrosis), traction bronchiectasis, honey-combing
- OGD + biopsy - oesophageal inflammation, ulceration, strictures, gastric antral vascular ectasia, Barrett’s metaplasia, adenocarcinoma may be present
- Serum muscle enzymes - elevated in scleroderma myopathy
- Electromyogram /nerve conduction studies - inflammatory myositis
- Muscle biopsy - inflammatory myositis
Define sarcoidosis.
Multisystem granulomatous inflammatory disorder.
Explain the aetiology / risk factors of sarcoidosis.
Unknown.
Transmissibel agents - e.g. viruses, atypical mycobacterium, Propionibacterium acnes
Environmental triggers
Genetic factors
Unknown antigen presented on MHC Class II complex of macrophages to CD4 Th1 lymphocytes, which accumulate and release cytokines (IL-1, IL-2).
Formation of NON-CASEATING granulomas in a variety of organs.
Summarise the epidemiology of sarcoidosis.
Uncommon.
20-40 year olds.
Africans.
Females.
Variable prevalence
UK 16 in 100,000
Highest in Irish women.
Recognise the presenting symptoms of sarcoidosis.
General
- Fever
- Malaise
- Weight loss
- Bilateral parotid swelling
- Lymphadenopathy
- Hepatosplenomegaly
Lungs
- Breathlessness
- Cough - usually unproductive
- Chest discomfort
- Minimal clinical signs - e.g. fine inspiratory crackles
Musculosksletal
- Bone cysts - e.g. dactylitis in phalanges
- Polyarthralgia
- Myopathy
Eyes
- Keratoconjunctivitis sicca - dry eyes
- Uveitis
- Papilloedema
Skin
- Lupus pernio - red-blue infiltrations of the nose, cheeky, ears, terminal phalanges
- Erythema nodosum
- Maculopapular eruptions
Neurological
- Lymphocytic meningitis
- Space occupying lesions
- Pituitary infiltration
- Cerebellar ataxia
- Cranial nerve palsies - e.g. bilateral facial nerve palsy
- Peripheral neuropathy
Heart
- Arrhythmia
- Bundle branch block
- Pericarditis
- Cardiomyopathy
- Congestive cardiac failure
Recognise the signs of sarcoidosis on physical examination.
General
- Fever
- Malaise
- Weight loss
- Bilateral parotid swelling
- Lymphadenopathy
- Hepatosplenomegaly
Lungs
- Breathlessness
- Cough - usually unproductive
- Chest discomfort
- Minimal clinical signs - e.g. fine inspiratory crackles
Musculosksletal
- Bone cysts - e.g. dactylitis in phalanges
- Polyarthralgia
- Myopathy
Eyes
- Keratoconjunctivitis sicca - dry eyes
- Uveitis
- Papilloedema
Skin
- Lupus pernio - red-blue infiltrations of the nose, cheeky, ears, terminal phalanges
- Erythema nodosum
- Maculopapular eruptions
Neurological
- Lymphocytic meningitis
- Space occupying lesions
- Pituitary infiltration
- Cerebellar ataxia
- Cranial nerve palsies - e.g. bilateral facial nerve palsy
- Peripheral neuropathy
Heart
- Arrhythmia
- Bundle branch block
- Pericarditis
- Cardiomyopathy
- Congestive cardiac failure
Identify appropriate investigations for sarcoidosis and interpret the results.
Bloods
- High serum ACE
- Hight Ca2+
- High ESR
- WCC low due to lymphocyte sequestration in lungs
- Immunoglobulins - polyclonal hyperglobulinaemia
- LFTs - high AlkPhos & GGT
24h Urine Collection
- Hypercalciuria
CXR
- Stage 0 - may be clear
- Stage 1 - bilateral hilar lymphadenopathy
- Stage 2 - bilateral hilar lymphadenopathy with pulmonary infiltration and paratracheal node enlargement
- Stage 3 - Pulmonary infiltration and fibrosis
High-Resolution CT Scan
- For diffuse lung involvement
67-Gallium Scan
- Shows areas of inflammation (classically parotids and around eye)
Pulmonary Function Tests
- Reduced FEV1, FVC and gas transfer
- Restrictive pattern
Bronchoscopy and Bronchoalveolar Lavage
- Raised lymphocytes
- Raised CD4:CD8 ratio
Transbronchial Lung Biopsy (or Lymph Node Biopsy)
- Non-caseating granulomas composed of epithelioid cells (activated macrophages)
- Multinucleate Langhans cells
- Mononuclear cells (lymphocytes)
Define ankylosing spondylitis.
Axial spondyloarthritis (AxSpa) = a chronic progressive inflammatory arthropathy.
Non-radiographic axial spondyloarthritis (nr-axSpA) = axial inflammation visible on MRI that has not caused substantial erosive damage to sacroiliac joints.
Explain the aetiology / risk factors of ankylosing spondylitis.
SERONEGATIVE SPONDYLOARTHROPATHY
- e.g. psoriatic arthritis, enteropathic arthritis, reactive arthritis.
= heterogenous group of conditions with overlapping clinical manifestations and associated with HLA-B27.
Mainly affects axial spine and sacroiliac joints.
Peripheral joints, entheses (tendon or ligaments attached to bone), and extra-articular sites (e.g. eye, bowel) are affected.
May lead to spinal fusion, following radiographical changes in spine and sacroiliac joints.
(Bamboo spine)
Risk factors:
- HLA-B27
- ERAP1 and IL23R genes
- Positive family history
- Male sex
- Klebsiella pneumoniae
Summarise the epidemiology of ankylosing spondylitis.
Epidemiology. Recent population estimates indicate that the prevalence of AS in the United States is approximately 0.2-0.5%. Based on data from multiple countries, the age- and sex-adjusted incidence of AS is 0.4-14 per 100,000 person-years.
Recognise the presenting symptoms of ankylosing spondylitis.
- Inflammatory back pain
- Iritis/uveitis
- Enthesitis
- Presentation in late teens and early 20s
- Male sex
- Positive family history of AS
- Fatigue
- Sleep disturbance
- Tenderness at sacroiliac joint
- Dyspnoea
- Loss of lumbar lordosis
- Peripheral joint involvement
- Kyphosis
- Psoriasis
- Symptoms of IBD
Recognise the signs of ankylosing spondylitis on physical examination.
- Inflammatory back pain
- Iritis/uveitis
- Enthesitis
- Presentation in late teens and early 20s
- Male sex
- Positive family history of AS
- Fatigue
- Sleep disturbance
- Tenderness at sacroiliac joint
- Dyspnoea
- Loss of lumbar lordosis
- Peripheral joint involvement
- Kyphosis
- Psoriasis
- Symptoms of IBD
Identify appropriate investigations for ankylosing spondylitis and interpret the results.
1st Line
- Pelvic XRay - sacroiliitis
Consider:
- HLA -B27 - positive or negative (not diagnostic!)
- MRI - bone marrow oedema on T2-weighted sagittal STIR image
- Spinal X Ray (lateral) - erosions, squaring, sclerosis, syndesmophytes, bridging syndesmophytes in the cervical & lumbar & thoracic spine, bamboo spine
- USS - enthesitis
Define gout.
Characterized by:
- Hyperuricaemia
- Deposition of urate srystals
- Acute inflammatory arthritis
- Tophi around joints
- Joint destruction
- Renal glomerular, tubular and interstitial disease
- Uric acid urolithiasis
Explain the aetiology / risk factors of gout.
Commonly affects:
- 1st toe
- Foot
- Ankle
- Knee
- Fingers
- Wrist
- Elbow
(can affect any joint)
Risk factors:
- Older age
- Male sex
- Menopausal status
- Consumption of meat, seafood, alcohol
- Use of diuretics
- Use of ciclosporin or tacrolimus
- Use of pyrazinamide
- Use of aspirin
- Genetic susceptibility
- High cell turnover rate
- Obesity
- Adiposity and insulin resistance
- Exogenous insulin
- Hypertension
- Renal insufficiency
- DM
- Hyperlipidaemia
- Family history of gout
Summarise the epidemiology of gout.
Recent reports of the prevalence and incidence of gout vary widely according to the population studied and methods employed but range from a prevalence of <1% to 6.8% and an incidence of 0.58–2.89 per 1,000 person-years. Gout is more prevalent in men than in women, with increasing age, and in some ethnic groups
Recognise the presenting symptoms of gout.
- Acute onset of severe joint pain
- Swelling
- Effusion
- Warmth
- Erythema
- Tenderness of involved joint
- Joint stiffness
- Foot joint distribution
- Few affected joints
- Tophi over extensor surface joints (elbows, knees, Achilles tendons)
- Family history of gout
Recognise the signs of gout on physical examination.
- Acute onset of severe joint pain
- Swelling
- Effusion
- Warmth
- Erythema
- Tenderness of involved joint
- Joint stiffness
- Foot joint distribution
- Few affected joints
- Tophi over extensor surface joints (elbows, knees, Achilles tendons)
- Family history of gout
