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Flashcards in SLE Deck (30):
1

Diff hypersensitivity rxns and examples?

- type I: immediate (anaphalytic, atopic)
- type II: cytotoxic: target cell receptors, platelet-thrombocytopenia, target fixed tissue ag; good pastures, MG
- type III: immune complex; vasculitis, SLE
- Type IV: cell mediated
a) tuberculin rxn
b) cytotoxic cells destroy target cells - allograft rej

2

What is SLE?

- multisystem autoimmune disorder of unknown cause and is strongly assoc w/ various autoabs
- deposition of ag-ab complexes along vascular and tissue basement membranes
- is sometimes referred to as the great imitator because it affects many diff body systems
- skin, its, serosal surfaces, muscles, kidneys, heart, lung, CNS, RBCs, and platelets

3

Incidence and prevalence of SLE?

- 50-70 new cases/1 million/year
- prevalence: 500/million
- women:men = 9:1
- occurs in childbearing yrs 20-40
- higher incidence in blacks, Native Americans, Puerto Ricans, Chinese

4

Factors for SLE?

influenced by combo of following:
- genetic: x'some 6: HLA-DR3 and linked specificities DR2 and DQw1 increase risk by a factors of 3
- enviro:
UV light (rash)
bacterial and viral infections
drugs
abnormal stimulation of immune system
- endocrine: sex hormes - most cases develop after menarche and b/f menopause
- drug induced:
lupus like syndrome - MC: procainamide, hydralazine

5

Pathogenesis of SLE?

- b-lymphocyte hyperactivity w/ exaggerated ab production
- ag-ab complexes deposited along basement membranes of vasculature and tissue
- localized inflammator responses:
complement
neutrophil migration
cell-mediated tissue injury
- onset may be insidious or acute (more devastating)
- course is characterized by exacerbations and remissions
- as in other autoimmune disorders - immune system attacks body cells and tissues, result is inflammation and tissue damage
- type III autoimmune rxn caused by ab- immune complex formation

6

MC sxs of SLE?

- systemic: low grade fever, photosensitivity
- mouth and nose: ulcers
- jts: arthritis
- muscles: aches
- psych: fatigue, loss of appetite
- face: butterfly rash
- pleura: inflammation
- pericardium: inflammation
- fingers and toes: poor circultation

7

Clinical manifestations of SLE?

constitutional:
- fatigue
- fever
- wt loss
- malaise
- anorexia
skin:
- butterfly rash (malar)
systemic: polyarthritis, arthralgias, jt pain (polyarthritis is symmetrical, but doesn't not involve articular destruction)
- alopecia
- fingertip lesions
- periungual erythema
- nail fold infarcts
- splinter hemorrhages
- raynaud's phenomen (about 20% of pts)

8

How common is renal involvement in SLE? Presentation? What can be prognostic?

- occurs in approx 50% of pts
- lupus nephritis:
glomerulonephrits
nephrotic syndrome: proteinuria, hyaline casts
- HTN
- renal bx can be prognostic:
glomerular sclerosis
fibrous crescents
interstitial fibrosis
tubular atrophy = poor outcome
- chronic renal failure more common than acute

9

Ocular features of SLE?

- conjunctivitis
- photophobia
- transient or permanent monocular blindness
- blurred vision
- cotton wool spots on retina

10

MSK features of SLE?

transient polyarthritis w/ symmetric involvement:
- small and large jts
- no signs of inflammation on exam of jts
- 10% develop rheumatoid like hand deformities
- bony erosions not present
osteonecrosis of the hips
fibromyalgia often present

11

Pulm features of SLE?

- occurs in 40-50% of pts
- transient basilar pneumonic infiltrates = lupus pneumonitis:
nonproductive cough
dyspnea
hypoxemia
- pleural effusions
- pleuritis
- bronchopneumonia
- restrictive lung disease
- rare: alveolar hemorrhage w/ massive hemoptysis, death

12

Cardiac features of SLE?

- occurs in 30-40% of pts
- pericarditis
- myocarditis
tachycardia
ventricular arrhythmia
conduction problems
CHF, cardiomyopathy
- increased muscle enzymes:
MB or CPK
- libman sacks endocarditis:
V. surface vegetations on valves
vegetation breakoff may allow colonizations

13

Serositis of SLE?

- pleuritis
- pericarditis
- peritonitis
- fluid less than 3000 WBC/mm3 = monocytes and lymphocytes
- reduced complement

14

Vascular features of SLE?

- raynaud's phenomenon
- arterial or venous thrombosis
- lupus vasculitis: palpable purpuric lesions on the shins in a pt w/ lupus and necrotizing vasculitis of the skin, kidney, and brain
- livedo reticularis: pt has antiphospholipid abs - can result in ulcer formation

15

GI sxs of SLE?

- transient, nonspecific abdominal pain
- increased incidence of primary biliary cirrhosis w/ SLE
- vasculitis of mesentery can cause infarction or perforation of bowel w/ high mortality

16

What are CNS features of SLE?

- occurs in 30-75% of pts
- confusion, memory deficits, disorientation, hypomania, delirium, and schizophrenia
- grand mal seizures, temporal lobe seizures
- severe HAs, MC neuropsych sx, sometimes w/ scotomata like migraines
- stroke: anti-phospholipid abs
- ACR recognizes 19 neuropsych syndromes in SLE

17

MC of death in SLE pts?

- those due to nephritis - usually occur w/in first 5 yrs of sx onset
- CV disease and malignancy which may be related to chronic inflammation and cytotoxic therapies, and common etiologies of late mortality
- infectious complications related to active SLE and immunosuppressive tx are now the most common COD in early active SLE

18

CBC findings in SLE? ESR, CRP, UA?

- anemia:
normocytic, normochromic, hemolytic
- leukopenia: lymphocytopenia common, indicative of disease activity
- thrombocytopenia: 50-100k
- prolonged PTT:
from antiphospholipid abs, false positive tests for syphilis

- ESR and CRP: both be elevated
- UA:
proteinuria
RBCs/WBCs
cellular or hyaline casts

19

Rheum lab findings in SLE?

- ANA (esp rim, cartwheel or peripheral): sensitivity 99%, specificity 49%
- anti dsDNA
- anti ssDNA
- anti ENA: anti SM, anti RNP
- elevated nonspecific IgG, IgM levels
- reduced complement levels (C3, C4)
- decreased IgA levels
- can have false positive for syphilis
- anti-histone: drug induced - ANA abs often this type

20

DDx for SLE?

- antiphospholipid syndrome
- FM
- hep C
- lyme disease
- lymphoma, B cell
- mixed CT disease
- polyarteritis nodosa
- rheumatic fever
- rheumatic arthritis
- scleroderma
- serum sickness
- TTP

21

How do you dx SLE?

- clinical
- no one test or feature is fully dx
- criteria for classification of SLE

22

What is the criteria for dx SLE?

- characteristic rash across cheek
- discoid lesion rash
- photosensitivity
- oral ulcers
- arthritis
- inflammation of membranes of the lungs, heart or abdomen
- evidence of kidney disease
- evidence of severe neuro disease
- blood disorders, including low red and white blood cell and platelet counts
- immunologic abnormalities
- positive ANA
* pt must experience 4 of the criteria b/f a doctor can classify the condition as SLE, these criteria proposed by ACR are not to be relied upon solely for dx however

23

Physical and lab findings in SLE?

- butterfly (malar rash)
- hypertension
- alopecia
- discoid lesions
- ANA (particularly cartwheel, rim or peripheral)
- dsDNA
- anti Sm ribonuclear protein
- hypocomplementemia
- UA:
WBC
RBC
proteinuria
hyaline casts

24

Tx of SLE?

incurable but tx
tx aimed at:
- reducing inflammation
- suppressing immune system
- closely follow pts clinically to ID disease features as early as possible
- pt education and prevention of disease flares:
sunscreen and protective clothing
protective, warm clothes
avoidance of vasoconstrictive drugs
psych support
routine immunization
- pharm tx:
glucocorticoids
antimalarials
immunosuppressants
IV immunoglobulin
plasmapheresis (Lupus nephritis)
Belimumab - fully human monoclonal ab (benlysta)

25

Survival rate for SLE pts?

- 95% at 5 yrs
- 90% at 10 yrs
- 78% at 20 yrs

26

Presentation of drug induced lupus?

- sex ratio nearly equal
- primarily msk, pulm, polyserositic sxs
- renal and neuro disease uncommon
- abs themselves not harmful
- no hypocomplementemia
- anti-nuclear abs present, but return to normal w/ withdrawal of drug
- reversal w/ d/c of drug
- procainamide and hydralazine MC culprits

27

Drugs that can cause drug induced lupus syndromes?

- antihypertensives:
hydralazine
methyldopa
- antiarrhythmics:
procainamide
quinidine
- anticonvulsants:
dilantin
zarontin
primidone
tegretol
- misc:
INH
sulfanamides
PCN
thorazine
PTU
tagamet
levodopa
BBlockers

28

What is discoid lupus?

- chronic cutaneous lupus
- involves plaque like lesions of head, scalp, and neck
- first appear as red, swollen patches or skin
- later scarring, depigmentation, plugging of hair follicles
- 90% of discoid lupus pts have disease that involves skin
- probably occurs in genetically predisposed individuals, but the exact genetic connection hasn't been determined
- pathophys of DLE isn't well understood

29

DDx for discoid lupus?

- actinic keratosis
- dermatomyositis
- keratocathomas
- granuloma annulare
- lichen planus
- subacute cutaneous lupus
- psoriasis
- rosacea
- sarcoidosis
- squamous cell carcinoma
- syphilis
- warts

30

Tx for discoid lupus?

- goals of management are to improve pt's appearance, to control existing lesions and limit scarring and to prevent the development of further lesions
- therapy w/ sunscreens, topical corticosteroids and antimalarial agents is usually effective