Page 573 - Clinical Hematology_ Theory _ Procedures ( PDFDrive )

CHAPTER 28 ■ Disorders of Hemostasis and Thrombosis: Blood Coagulation Factors, Hypercoagulable State, and Anticoagulant Therapy 557

with a brinogene ia or ys brinogene ia ay eve o
Coagulation Factor Assays for

TABLE 28.7 Autosomal Recessive Factor thro bosis.
When aboratory assays base on the ro uction o a
Disorders
brin c ot are er or e , atients with a brinogene ia

Factor APTT PT TT Fibrinogen e onstrate abnor a activate artia thro bo astin
ti e(AP ), rothro bin ti e (P ), an thro bin ti e

Factor I type I A A A Absent ( ) assay resu ts. A o these assays are correcte in ix-

A brinogenemia ing stu ies with nor a as a. P ate et aggregation tests are

Factor I type I N N A N abnor a because brinogen is require or ri ary ate et

Hypo brinogenemia aggregation. Con r ation o the iagnosis is by antigenic
an unction assays or brinogen.
Factor I type 2 N N A Variable

Dys brinogenemia Inherite brinogene ia ust be i erentiate ro
acquire con itions. In ty e II, ys brinogene ia, atients
Factor II A A N N have nor a quantities o brinogen but abnor a o ecu es.

Factor V A A N N Genetic utations in a three genes enco ing or the brino-

Factor VII N A N N gen e ti e chains (FGA, FGB, or FGG) have been i enti e .
In cases o ys brinogene ia, the activate artia
Factor X A A N N
thro bo astin ti e(AP ), rothro bin ti e (P ), an
Factor XI A N N N thro bin ti e ( ) assays are ro onge . In a ition, a

Factor XII A N N N c ot-base quantitative brinogen assay an re ti ase ti e

Factor XIII N N N N are abnor a .

Prekallikrein A N N N Factor V (Labile Factor)

Fletcher factor T is autoso a actor e ciency, known as Owren isease

High molecular A N N N or arahe o hi ia, can exist in i , o erate, or severe

weight kininogen or s. Factor V e ciency can exist in a quantitative ty e 1 or

qua itative ty e 2 or . T e e ciency ay be associate with

co bine inherite e ciency o actor VIII, but there is no
Uncom m on Hereditary Clotting De ciencies a arent cu u ative b ee ing e ect in a co bine e ciency.

Autoso a recessive e ciencies o the other coagu ation Laboratory testing. activate artia thro bo astin

actors are re ative y rare. Exa es o rare e ects inc u e ti e(AP ) an rothro bin ti e (P ) are ro onge but

actor e ciencies inc u ing actors I, II, V, VII, X, XI, the thro bin ti e ( ) is nor a . Abnor a b ee ing ti es

XII, an XIII, as we as high o ecu ar weight kininogen occur in one-thir o atients an ay be re ate to a e -

(HMWK) (Fitzgera actor) an reka ikrein (F etcher ciency o actor V in ate et α-granu es.

actor). Laboratory screening tests ( ab e 28.7) i erentiate

these coagu ation actors. Factor XIII A or Factor XIII B (Fibrin Stabilizing Factor)

Tese e ciencies are genetic utation a ecting either the
Fibrinogen Group A or B chains o FXIII. A e ciency is associate with severe

In the brinogen grou o actors I, V, VIII, an XIII, throm- b ee ing. It ay be congenita or acquire in inf a atory

bin c eaves a our coagu ation actors in this grou . T ey are isease. Factor XIII e ciency is associate with s ontane-

consu e uring c otting, an as a resu t, they o not exist ous abortion an oor woun hea ing.

in seru . Factor XIII unctions a er or ation o brin; a e -

ciency oes not a ect the activate artia thro bo astin
Factor I (Fibrinogen) ti e(AP ), rothro bin ti e (P ) an thro bin ti e

his autoso a recessive ibrinogen e iciency ay ( ) screening tests.

exist as absent or ecrease eve s o brinogen (ty e I he ty e o testing e en s on whether the e iciency

isor ers), a brinogene ia, or hy o brinogene ia, res ec- is sus ecte to be inherite or acquire . Acquire ac-

tive y. A brinogene ia usua y resents in chi hoo . tor XIII e iciency eva uation shou start with a unc-

A brinogene ia is associate with a severe b ee ing ten- tiona assay to etect e iciency. I a severe e iciency is

ency but is ess co on than hy o brinogene ia. Patients i enti ie , o ow u with a ixing stu y to eva uate. An

with hy o brinogene ia are usua y asy to atic exce t in interesting aboratory in ing is that a atient’s b oo c ot

situations o surgery or trau a. is so ub e in a 5-M urea so ution. I c ot ysis occurs in

Pro uction o ys unctiona o ecu es ro uces ys - initia testing, then the test is re eate using a 1:1 ix

brinogene ia (ty e II). Patients with ys brinogene ia ay o atient as a an oo e nor a as a to istin-

be asy to atic or ex erience a i b ee ing ten ency guish between FXIII e iciency an a FXIII inhibitor.

i heterozygous or the e ect, or they ay have a severe Abnor a resu ts shou be con ir e with quantitative

b ee ing ten ency, i ho ozygous or the e ect. Patients testing or actor XIII.