Page 534 - Clinical Hematology_ Theory _ Procedures ( PDFDrive )

518 PART 7 ■ Principles and Disorders of Hemostasis and Thrombosis

Drug-Induced Platelet Dysfunction

Many rugs such as as irin, other NSAIDs, cyc ooxygen-

ase-2 (COX-2) inhibitors, an antibiotics can in uce ate et

unction e ects. T e ost co on echanis s o inter-

erence invo ve rug inter erence with ate et e brane

or e brane rece tor sites, rug inter erence with rosta-

g an in biosynthetic athways, an rug inter erence with

hos ho iesterase activity. P ate et e brane rece tors can

be a tere by rugs, such as ch or ro azine (T orazine,

G axoS ithK ine Research riang e Park, NC), cocaine,

Xy ocaine, ce ha othin (Kef in, E i Li y, In iana o is, IN),

a ici in, enici in, an a coho . In a ition, rostag an-

in athways are inhibite by as irin, ibu ro en, hy rocorti-

sone, an cyc os orine (San i une, Neura , NOVAR IS,

Base , Switzer an ).

FIGURE 26.10 He o ytic-ure ic syn ro e. Fibrin thro bi Large oses o various β- acta antibiotics, such as eni-
an rag ente re b oo ce s occ u e g o eru ar ca i aries, ci ins an ess o en ce ha os orins, can cause b ee ing.

an brin is seen in an arterio e. (He atoxy in an eosin, origi- Abnor a ate et unction in vitro an in vivo an increase

na agni cation 400×.) (Fro Stocker J , Dehner LP, Husain AN. b ee ing ti es can be observe . A ose- e en ent re uc-
Stocker and Dehner’s Pediatric Pathology, 3r e , Phi a e hia, PA, tion in ate et aggregation in vitro to ADP, e ine hrine, an

Li incott, Wi ia s & Wi kins, 2010.) co agen is seen. β-Lacta antibiotics a ear to o i y the

ate et e brane an ecrease agonist bin ing.

■ S a vWF u ti ers re o inate

■ Nor a eve o ADAM S13 activity Paraprotein Disorders

HELLP Syndrom e Para rotein isor ers, inc u ing a ignant or benign ara-
rotein, such as u ti e ye o a, Wa enströ ’s acro-
HELLP syn ro e is na e or three eatures o the is- g obu ine ia, or other onoc ona ga o athies, harbor

ease—he o ysis, e evate liver enzy e eve s, low p ate et ate et ys unction. Dys unction resu ts ro the ara ro-

count that are i e-threatening otentia co ication o ate tein coating the ate et e branes but oes not e en

regnancy or e ivery. HELLP was once known as e e a- on the ty e o ara rotein resent. A ost a atients with

roteinuria-hy ertension gestosis ty e B in the ear y 20th a ignant ara rotein isor ers wi e onstrate c inica y

century an was rena e in 1982. HELLP is be ieve to signi cant b ee ing an abnor a ate et unction by

be a severe or o reec a sia, gestationa hy ertension aggregation.

acco anie by roteinuria a er the 20th week o gestation,

or an entity o its own. T e con ition resu ts in vascu ar ce Cardiopulm onary Bypass and Platelet Function

injury ea ing to an increase risk o thro bo hi ia.

T e etio ogy o HELLP is uncertain. Risk actors associate T ese con itions e onstrate severe ate et unction e -

with HELLP syn ro e inc u e aterna age o o er than 34 cit that assu es ajor i ortance in surgica b ee ing a er

years, u ti arity, rior regnancies, an Euro ean escent. by ass.

An injury to the icrovascu ar o the b oo vesse ining

ro uces en othe ia activation o b oo coagu ation with Clonal Hem atopoietic Disorders: MDS and Acute

i to o erate re uction in ADAM S13. T e ADAM S13 Myelogenous Leukem ia (AML)

gene rovi es instructions or aking an enzy e that is P ate et ys unction can contribute to i aire he ostasis

invo ve in b oo c otting. in MDS an acute ye ogenous euke ia (AML). De ects in

Activation o the coagu ation casca e causes consu - egakaryocyte aturation occur with hy ogranu arity an

tion o ate ets because o ate et a hesion to a age an hy o obu ation ate et characteristics. Other u trastructure

activate en othe iu . In a ition, a con ition o icro- abnor a ities inc u e exaggerate size variation, a i ate

angio athic he o ysis occurs that is cause by shearing o cana icu ar syste , structura y abnor a argina icrotu-

erythrocytes as they trave through ca i aries c ogge with bu es that are ecrease in quantity, an granu ar ys asia.

ate et- brin e osits. Mu tiorgan icrovascu ar injury an P ate et granu es are either severe y re uce or extre e y

he atic necrosis cause iver ys unction. T e ost co on arge because o the usion o u ti e granu es.

reasons or others to beco e critica y i or ie are he atic

ru ture or stroke (cerebra e e a or cerebra he orrhage). Clonal Hem atopoietic Disorders Myeloproliferative

Laboratory n ings inc u e a circu ating ate et count o Disorders (MPNs)

9
ess than 100 × 10 /L as a resu t o ate et consu tion. T e Po ycythe ia vera (PV), essentia thro bocytosis or E , an
activate AP an P are usua y nor a unti ate in the ri ary ye o brosis (PM) were i enti e as athogeneti-

isor er. ca y re ate ye o ro i erative isor ers in 1951.