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-!ite!ia fo! t*e +ia)nosis o+ PM/DM

5. M&sc"e (eakness#&s&a""y ,!o4ima" an+ symmet!ica"

6. Positie m&sc"e 3io,sia

7. E"ect!omyo)!a,*ic t!ia+ of s*o!t' sma""' ,o"y,*asic moto! &nits' fi3!i""ation'

,ositie s*a!, (aes an+ inse!tiona" i!!ita3i"ity' an+ 3i8a!!e' *i)* f!e%&ency

!e,etitie +ic*a!)es

9. Raise+ -K actiity

. Any one of t*e c*acta!estic +e!mato"o)ic feat&!es of !as* of +e!matomyositis

A' *e"iot!o, !as* 0!e+#,&!,"e e+emato&s e!yt*ema on t*e &,,e! ,a",e3!a2

;' ott!ons si)n 0!e+#,&!,"e ke!atotic' at!o,*ic e!yt*ema' o! mac&"es on t*e

e4tenso! s&!fe of fin)e!

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-"assification of inf"ammato!y myo,at*y

Clinical groups

!o&, 5: ,!ima!y i+io,atic ,o"ymyositis

!o&, 6: ,!ima!y i+io,at*ic +e!matomyositis

!o&, 7: +e!matomyositis 0o! ,o"ymyositis2 associate+ (it* neo,"asia

!o&, 9: c*i"+*oo+ +e!matomyositis 0o! ,o"ymyositis2

!o&, : ,o"ymyositis o! +e!matomyositis associate+ (it* ot*e! connectie tiss&e +isease

!o&, =: inc"&sion 3o+y myositis

Serological groups

A&toanti3o+y anti)en

Anti#synt*etase 5 of kno(n amaminoacy"#tRNA synt*etase

Anti#SRP ,!oteins of si)na" !eco)nition ,a!tica"

Anti#Mi#6 +i!ecte+ a)ainst a 66>kDa n&c"ea! ,!otein

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NI? c"assification of IIM &ti"i8in) t*e MSA stat&s an+ imm&no)enetics

DR(6 associate+:

5. aminoacy"#tRNA synt*etase

6. SRP

7.

DR(7 associate+

5. Mi#6

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Pat*o"o)ic c*an)es of m&sc"e in +e!matomyositis

Muscular histopathology

,e!iasc&"a!' ,e!ifascic&"a! inf"ammation'

at*!o,*y'

asc&"a! +ama)e' isc*aemia'

se)mentia" fi3e! nec!osis

M&sc&"a! cyto,at*o"o)y

*i)*e! ,e!centa)e of ; "ym,*ocytes an+ -D9C "ym,*ocytes

Pe!i,*e!a" cyto,*ato"o)y

+ec!ease+ -D7C an+ TLISAC monon&c"ea! ce""s'

inc!ease+ -D6>C an+ -D6>CDRCce""s

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Anti#Mi#6 syn+!ome

Clinical manifestations

-"assic +e!matomyositis (it* 1 si)n' s*a(" si)nOnset of myositis

Rate: ac&ta

See!ity: mi"+

Season: &nkno(n

Response to therapy

oo+' !as* may ,e!sist

Prognosis : oo+' #y s&!ia" !ate of nea!"y 5>>HLA associations: DRB' DR7' DFA5G>6>5

Frequency in myositis: #5>

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Antisynt*etase syn+!ome

-"inica" manifestations

A!t*!itis' inte!stitia" "&n) +isease' fee!' mec*anics *an+s' Rayna&+s

fenomenon

Oneset of myositis

Rate: ac&te

See!ity: see!e

Season: s,!in)Response to therapy: mo+e!ate' f"a!es (it* ta,e!in) t*e!a,y

Prognosis:,oo!' #y s&!ia" of B>

HLA associations: DR7' DR(6 DFA5G>>5

Frequency in myostitis: 6>#6

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Immune mechanisms in inflammatory myopathies

De!matomyositis

- antibody or immune-complex-mediated respones

against a vascular-endothelial component

- deposition of the complement membrane complex in or

around microvascular endothelium

- focal capillary depletion

- perifascicular atrophy

Po"ymyositis an+ I;M

- endomysial inflammatory exudate containing large

numbers of C!" # cells

- all if the invaded fibers express $%A class Iag

- $%A class-I-restricted cytotoxic # cell mediated

response against surface ag expressed by muscle fibers

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&athologic changes of muscle in polymyositis

M&sc&"a! *isto,at*o"o)y

$ascic&"a!/en+omysia" inf"ammation' (it*o&t ,e!ifasc&"a! at!o,*y

M&sc&"a! cyto,at*o"o)y

?i)*e! ,e!centa)e of T "ym,*ocytes -DHC "ym,*ocytes an+ actiate+

T ce""s

it* minima" ; "ym,*ocyte ino"ement

Pe!i,*e!a" cyto,at*o"o)y

Inc!ease+ -D7CDRC monon&c"ea! ce""s' an+ -D7CDRC/DRC !atio

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T!eatment of myositis

$ist#"ine t*e!a,y

'lucocorticoid -* mg+,g+d - month

Secon+#"ine t*e!a,y

A.othioroprine -* mg+,g+d

Methotrexate /01-*1 mg+2ee,

Cyclophosphamide *- mg+,g+d

$ydroxycloro3uine *44-544 mg+d

Cyclosporin A -1 mg+,g+d

Intravenous immune globuline g+,g+d * days+month

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Mec*anism of action if I1I

6 7c receptor bloc,ade in the reticuloendothelial system

*6 increase in suppressore activity

6 inhibition of autoreactive 8 cells that carry the autoreactive clones of anti-

idiotypic antibodies

56 modulation of cyto,ine production

16 neuralie complement0 this preventing the formation of membrane attac,

complex