Systemic Sclerosis and Inflammatory myopathies Flashcards
(26 cards)
Systemic Sclerosis gender prediliciton, age group
F:M = 3:1
Peak 40-60yo
Risk factors for systemic sclerosis
HLA-DRB1, STAT4, interferon genes
Silica, organic solvents, vinyl chloride
Diffuse Vs Limited Systemic Sclerosis
In diffuse:
- Raynauds Shorter Hx
- Rapid onset skin changes, contracture
- More constitutional Symptoms
Early onset Internal organ involvement (ILD, renal crisis)
Serum Abs in Systemic Sclerosis
Scl-70 (topoisomerase 1) -> ILD
Centromere -> protection from ILD/ renal disease, much more common in limited
RNA Polymerase III -> renal, skin involvement, malignancy
U1-RNP - overlap features
Th/ To - PAH
Average decrease life span with scleroderma?
23 years of life lost in women and 26 years of life lost in men
Highest mortality among the rheumatic diseases.
Management of Systemic sclerosis
Often symptomatic relief only
Monitor for new organ involvement
- ILD or renal disease first 5 years dcSSc (4-6 monthly HRCT)
- PHTN - anytime, both groups (BNP, PFTs, ? TTE +/- RHC if sus)
Radiological pattern of Pulm HTN in Systemic Sclerosis
NSIP > UIP
Predictors of worsening Systemic Sclerosis?
Male,
African American
dcSSc
biomarkers - SCL70 Ab, etc etc
Pulm HTN
- FVC < 70,
- DLCO < 55%,
- HRCT fibrosis bad
Systemic Sclerosis ILD management?
PPIs, quit smoking, vaccinate, O2 as needed
1st line: mycophenelate
2nd line: cyclophosphamide, followed by MMF or azathioprine
3rd line: ?nintendandib (good new evidence for)/ pirfenidone/ rituximab/ tocilizumab/ lung transplant/ stem cell transplant
Pulm HTN Group in Systemic Sclerosis
Group 1 - pre-capillary
Difference vs pre/ post capillary pull HTN on RHC?
Pre:
- PAWP <= 15mmHg,
- WU >= 3
Post:
- PAWP > 15
- WU < 3
Treatment of Pulm HTN in Systemic Sclerosis
Use meds based on severity
- no real role CCBs
- endothelial receptor antagonists (ambrisentan, bosentan, macitentan),
- PDE-5 inhibitors (sildenafil, tadalafil)
- rociguat
- if severe: IV epoprostenol
- ? prostacyclin analogues (iloprost, treprostinil)
RCTs included patients with CTD-PAH but the effects of PAH specific therapies were not as significant as for iPAH
Clinical features Scleroderma Renal Crisis?
- Abrupt onset of moderate to severe hypertension
- Progressive renal failure
- Normal urine sediment or only mild proteinuria with few cells or casts
Signs of more severe SRC (Reflect underlying vasculopath/ HTN)
* MAHA/ thrombocytopenia
* Heart failure/ flash pulmonary oedema
* Blurred vision due to retinopathy
* Headache, fever, malaise
* Encephalopathy - may be complicated by generalized seizures
* Pericardial effusion
Risk Factors for Scleroderma Renal Crisis?
- diffuse SSc (10-20%),
- RNA polymerase III Ab,
- tendon friction rubs
- corticosteroids
Management of scleroderma renal crisis?
BP control
- ACEi
- IV nitroprusside (CNS involved)
Consider ICU
Wean/ Cease steroids
Dialysis
? renal transplant
Prognostic factors scleroderma renal crisis?
Worse in:
- males
- not that hypertensive initially
- already on ACEi
Treatment for Raynaud’s?
Treat underlying cause
1st line: CCB
2nd line: ARB/ PDE5i/ nitrates/ alpha blockers/ SSRI/ anti-platelet/ statin
3rd line: IV prostacyclins botox
4 Main types Inflammatory Myopathy?
- Polymyositis (PM)
- Dermatomyositis, including amyopathic DM
- Inclusion body myositis (IBM)
- Immune-mediated necrotising myopathy (IMNM) * (+overlap myositis)
Characterized by the shared features of proximal skeletal muscle weakness and evidence of immune-mediated muscle inflammation and distinct clinical, serological, histopathological features
Pathophys of Inflammatory Myopathies
Clinical features of Dermatomyositis/ Polymyositis?
Symmetrical muscle weakness (90%)
- w myalgia/ tenderness
- delts + neck/ hips (flexors)
- diaphragm, intercostal muscles -> hypoventilation
Rash
- heliotrope rash
- shawl sign (poikiloderma)
- Gottron’s papules/ sign
Myocarditis +/- MI
ILD (10%)
Ix in PM/ DM
Elevated muscle enzymes: CK/ transaminases/ LDH/ aldolase
- 10x ULN
- may not correlate well with weakness
ANAs
- myositis specific (30-40%) or myositis associated
EMG - differentiate from neuropathy
MRI
Muscle biopsy - good to have MRI b4 to target
Anti-synthetase syndrome
- up to 30% PM and DM
- mechanic’s hands
- constitutional symptoms
- myositis
- Raynaud phenomenon
- non-erosive arthritis
- ILD
- Abs to aminoacyl-transfer ribonucleic acid
(tRNA) synthetase enzymes
Clinically Amyopathic Dermatomyositis (CADM)
- 10-30% of DM
- classic cutaneous features of DM without muscle
involvement - increased risk of malignancy (<DM)
- may be more likely if also MDA5+ve
Investigations for DM/ PM Complications
Malignancy
- age appropriate screening
- physical exams
- lab testing (???)
Cardiac
- TTE/ ECG
Pulm:
- PFTs, HRCT
Oesophageal dysfunction
- oesophageal dysmotility studies
