Systemic lupus erythromatosous Flashcards
Define
Multisystem
Autoimmune, autoantigens
Pathophysiology
Polyclonal B cell secretion of autoantibodies->immune complexes, deposit
Epidemiology
+++Women
Reporductive age
10% relatives affected
Clinical features
Relapsing and remitting Malaise, fatigue, weight loss, myalgia, fever Raynauds oral ulcers nose ulcers alopecia arthralgia/arthritis fibromyalgia poorly localised proximal limb inflammatory pain with weakness Raynaud's phenomenon chest pain and shortness of breath dysrhythmias (e.g., tachycardia), conduction defects, or unexplained cardiomegaly hypertension signs of nephrosis (e.g., oedema) lymphadenopathy CNS signs: seizures, cranial nerve abnormalities, cognitive defects, psychosis venous or arterial thrombosis abdominal pain, vomiting, or diarrhoea dysphagia
Immunology
95% +ve for ANA
anti-dsDNA highly specific, only 60% +ve
Anti-Smith, Anti-Ro, Anti-cardiolipin
Associated with other AI conditions->Sjogrens, thyroid
Investigations
Anti-dsDNA antibody titres ANA Complement->reduced C3, C4 ESR->elevated BP Urine for casts, protein FBC->normochromic, normocytic anemia, thrombocytopenia, leukopenia UEC->+urea and creatinine LFTs CRP usually normal aPTT->prolonged if APS CXR->effusions, cardiomegaly
Drug-induced
Isoniazid Hydralazine Procainamide Quinidine Chlorpromazine Skin and lung signs++
CLOT abnormalities in APS and treatment
Anti-cardiolipin, lupus anticoagulant Coagulation defect Livedo reticularis Obstetric complications Thrombocytopenia
Use low dose aspirin
Management of
Lifestyle: smoking cessation, diet, exercise, sun protection/avoidance for ALL
1. Arthritis
->Naproxen
If inadequate:
->Hydroxychloroquine
->Prednisilone
->Methotrexate + folic acid
2. Mucocutaneous
->Oral hygeine
->Lidocaine gel
->Antiseptic mouth wash
->Prednisilone, hydroxychloroquine, methotrexate + folic acid
3. Nephritis
->Induction therapy (cyclophosphamide) + prednisilone + hydroxychloroquine
->Maintenance with azathioprine and prednisilone
Steroid sparing agents
Methotrexate
Mycophenolate
Azathioprine
Prognosis
80% survival at 15 years
Revised criteria for diagnosis of SLE
A RASH POINTS MD
Any ≥4 of the 11 criteria are required to classify a patient as having SLE. These criteria can be present serially or simultaneously during any interval of observation.
1. Malar rash
->Fixed erythema, flat or raised, over the malar eminences, tending to spare the nasolabial folds.
2. Discoid rash
->Erythematous raised patches with adherent keratotic scaling and follicular plugging; atrophic scarring may occur in older lesions.
3. Photosensitivity
->Skin rash as a result of unusual reaction to sunlight, by patient history or physician observation.
4. Oral ulcers
->Oral or nasopharyngeal ulceration, usually painless, observed by physician.
5. Arthritis
Non-erosive arthritis involving ≥2 peripheral joints, characterised by tenderness, swelling, or effusion.
6. Serositis (one of the following):
->Pleuritis: convincing history of pleuritic pain, pleural rubs on auscultation, or evidence of pleural effusion.
->Pericarditis: documented by ECG, pericardial rub, or evidence of pericardial effusion.
7. Renal disorder (one of the following):
->Persistent proteinuria >0.5 g/day or >3+ if quantification not performed.
->Cellular casts: may be red cell, haemoglobin, granular, tubular, or mixed.
8. Neurological disorder (one of the following):
->Seizures: in the absence of offending drugs or known metabolic derangements; for example, uraemia, ketoacidosis, or electrolyte imbalance.
->Psychosis: in the absence of offending drugs or known metabolic derangements; for example, uraemia, ketoacidosis, or electrolyte imbalance.
9. Haematological disorder (one of the following):
->Haemolytic anaemia: with reticulocytes
->Leukopenia, Thrombocytopenia
10. Immunological
->Anti-DNA: presence of antibody to native DNA in abnormal titre
->Anti-Smith: presence of antibody to Smith nuclear antigen
->Positive findings of antiphospholipid antibodies based on:
An abnormal serum level of IgG or IgM anticardiolipin antibodies
->Positive test result for lupus anticoagulant using a standard method
->A false-positive serological test for syphilis known to be positive for at least 6 months and confirmed by Treponema pallidum immobilisation or fluorescent treponemal antibody absorption (FTA) test.
->Anti-nuclear antibody
11. An abnormal titre of anti-nuclear antibody by immunofluorescence or an equivalent assay at any point in time and in the absence of drugs known to be associated with drug-induced lupus syndrome.
Most important complication of SLE
Renal involvement
Hypertension, CRF, nephrotic, ESRD
Main causes of death
Renal
CNS
Infection
Vascular disease
Which infection can show a false positive
VDRL->syphillis
