Rheum Flashcards
What are somereasons patients with rheumatological conditions may need ICU care?
- End organ failure due to complications of their rheumatological disease
- Severe/atypical infection due to immune suppression
- Drug reaction from therapy for their rheumatological condition (DMARDs)
- Acute compromise unrelated but exacerbated by their condition or treatment e.g. bowel obstruction/perforation complicated by skin/wound problems or immunosuppression.
Why are rheumatological conditions important in critical care?
- immunosuppression- difficult to differentiate from sepsis- difficult to diagnose- require a high degree of suspicion- can have a high mortality
What is Macrophage Activation Syndrome (MAS)?
Macrophage activation syndrome is a form of haemophagocytic lymphohistiocytosis (HLH).Primary (genetic)
HLH is mainly a disease of infancy.
Secondary (acquired) HLH/MAS may occur in:
- malignancy
- Inflammatory/Rheumatological conditions (systemic juvenile idiopathic arthritis, adult onset stills disease, SLE, vasculitis)
- Organ transplant patients
- acquired immunodeficiency
- secondary to sepsis
It is characterised by loss of regulation of the immune response leading to macrophage and T cell mediated hyper inflammation with associated cytokine storm.Clinically it presents with a:
- sepsis/SIRS type picture
- multiorgan involvement/dysfunction
- persisting fevers.
- coagulopathy/DIC
- lymphadenopathy/splenomegaly/hepatomegaly
- neurological features
- confusion, seizures, comaBiochemically it shows a:
- pancytopenia (may be thrombocytopenia predominantly)
- markedly elevated ferritin
- elevated triglycerides
What is the management of macrophage activation syndrome?
Manage the patient in an ABCDE approach.Specific features include:
- early aggressive supportive care and organ support.
- Elimination of suspected trigger(s).
- differentiation and exclusion of infection (often difficult)- immunosuppression with high-dose corticosteroids +/- cyclosporin
- IVIg may have a role
- vigilance for secondary infection
What is scleroderma renal crisis and how is it managed?
Scleroderma renal crisis is the presence of severe hypertension and rapidly declining renal function leading to oliguria/anuria in a patient with systemic sclerosis.It is thought to be due to arterial renal vessel wall involvement/thickening leading to reduced perfusion and excessive renin release.Patients may present with neurological features of hypertension or renal failure:
- oedema
- pulmonary oedema
- encephalopathy
- seizures
- headache
- LVF
Patient should be managed in A to E approach correction abnormalities as they are found.The specific focus of care is:- controlled reduction in blood pressure- prevention of permanent renal damage.
- ACEi are central to treatment
- may be supported with beta blockers, CCBs and GTN.
- RRT may be required
- Plasma exchange may be required
Prognosis:
- renal function may never fully recover and may take a long time to liberate from RRT (up to 36 months).
– overall 5 year mortality is about 35%
What is vasculitis?
Inflammation of blood vessels. Vasculitis refers specifically to an immune-mediated or autoimmune inflammation.It can be divided into size of blood vessels it affects:
- large vessel (Takayasu’s, giant cell)
- medium vessel (Buerger’s, Kawasaki’s, polyarteritis nodosa)
- small vessel (EGPA, GPA, Bechet’s, HSP, microscopic polyangiitis (MPA))Or the presence of associated serological phenomena:- ANCA positivity (EGPA, GPA, MPA)- ANCA negative
What are the anti-neutrophil cytoplasmic antibody (ANCA) associated vasculitides? How can they be differentiated?
- Eosiniophilic granulomatosis with polyangiitis (EGPA - Churg-strauss)
- Granulomatosis with polyangiitis (GPA - Wegener’s)
- Microscopic polyangiitis (MPA)
- EGPA - presence of eosinophilia, more likely to have cardiac involvement (pericarditis, myocarditis, dysrhythmias), nasal polyps, myeloperoxidase (MPO) antigen positive, pANCA, biopsy
- extravascular eosinophils
- GPA - More likely to have pulmonary involvement, pulmonary haemorrhage and subglottilc stenosis, proteinase 3 (PR3) antigen positive, cANCA positive, biopsy
- granulomas with multi-nucleated giant cells.
- MPA - more likely to have renal involvement as leading abnormality, but others also likely to have renal involvement, myeloperoxidase (MPO) antigen positive, pANCA positive
What are the potential complications of ANCA positive vasculitis in critical care patients?
Usually small vessel disease, so any organ can be affected.Predominantly associated with clinical features of:
- Renal impairment: uraemia, hyperkalaemia, fluid overload
- pulmonary impairment: hypoxia, hypercarbia, diffuse alveolar haemorrhage, ARDS picture, subglottilc stenosis (GPA)
Other complications:
- cardiovascular: hypotension, arrhythmias, pericarditis, myocarditis
- gastrointestinal: perforation, ulceration, pancreatitis, hepatitis
- neurological: cerebritis, encephalopathy, seizures, confusion, coma
- skin: cutaneous involvement, ulceration, rashes
- drug therapy related: immunocompromised infections, adverse drug reactions or side effects.
What are the treatments for ANCA vasculitis?
- steroids- cyclophosphamide- rituximab- plasma exchange
What pharmacological therapies are you aware of for rheumatological disease?
- steroids for broad immune suppression and control of flare ups
- DMARDs e.g. methotrexate (analogue of folic acid), sulfasalazine
- Biologics e.g. anti-TNF (infliximab, ertanercept), IL-6 inhibitors (tocilizumab), B cell depletors (rituximab)