Page 485 - Clinical Hematology_ Theory _ Procedures ( PDFDrive )

CHAPTER 23 ■ Myeloproliferative Neoplasms 469

Tis con ition l cks PDGFRA, PGDFRB, n FGFR1 ■ Te i gnosis o essenti l thro bocythe i is i cult

ut tions. CEL-NOS is ef ne by tot l peripher l n relies on the exclusion o other yeloproli er tive

bloo eosinophil count o ≥1.5 × 10 /L th t persists over st tes n nonhe tologic l illnesses ssoci te with n
9
ti e, evi ence o clon lity, or gre ter th n 2% yelobl sts incre se concentr tion o pl telets.

in peripher l bloo n 5% to 19% yelobl sts in the ■ Essenti l thro bocythe i is r re isor er.

bone rrow n tot l peripher l bloo leukocyte count ■ T ro botic or blee ing proble s re the ost co only

gre ter th n 30 × 10 /L with 30% to 70% eosinophils. seen isor ers in p tients with thro bocythe i .
9

Polycythemia Vera Mastocytosis

■ PRV is istinguishe ro the other kin s o MPN by ■ M st cells secrete v riety o v so ctive n proin -

the re rk ble incre ses in re bloo cell ss n tot l tory e i tors in their gr nules n high- nity

bloo volu e. IgE-bin ing sites.

■ T e e n ge t i gnosis r nges ro 60 to 65 ye rs. ■ M stocytosis is unique n r re neopl s ef ne by

■ Te ost serious co plic tions re v scul r cci ents n bnor l exp nsion n ccu ul tion o clon l st cells

the tr nsition to cute leuke i . (MCs) in one or ultiple org n syste s such s the skin,

■ PRV is consi ere to be chronic ise se with 10- to bone rrow, spleen, n g strointestin l tr ct.

20-ye r li e expect ncy er i gnosis. ■ Syste ic stocytosis is clon l isor er ch r cterize

by so tic ut tion o the c-KI protooncogene.

Primary Myelo brosis

■ Pri ry yelof brosis is clon l isor er o the ultipo- Myeloproliferative Neoplasm, Unclassi able
tenti l progenitor cell co p rt ent. (MPN-U)

■ Te pre o in nt clinic l ni est tion occurs secon - ■ Tis c tegory, MPN-U, which y ccount or 10% to 15%
rily n is not co ponent o the bnor l clon l o MPN isor ers, c ptures isor ers th t express yelo-

proli er tion. T e process o f brosis ensues ro the pro- proli er tive ch r cteristics but either il to eet the cri-
li er tion o f brobl sts n incre se coll gen pro uction teri o specif c con ition or h ve e tures th t overl p

in re ction to the bnor l clone o he topoietic cells. with two or ore specif c con itions.

■ Dys eg k ryocytopoiesis le ing to n overpro uc- ■ Most c ses o MPN-U ctu lly ll into one o three c t-

tion o e ective pl telets is the ost const nt e ture o egories: polycythe i ver , essenti l thro bocythe i , or
yelof brosis.
pri ry yelof brosis. P tients re in very e rly st ge o

Essential Thrombocythemia ise se in which they o not e onstr te the est blishe
criteri or the c tegory or re t l te st ge o v nce

■ Essenti l or pri ry thro bocythe i (essenti l thro - MPN.
bocytosis) is ch r cterize by signif c nt incre se in cir- ■ P tients cl ssif e s MPN-U l ck Phil elphi chro o-

cul ting pl telets, usu lly in excess o 1,000 × 10 /L. so e n BCR-ABL usion gene.
9

CASE STUDIES

12
Case Study 23.1 Erythrocyte count 9.2 × 10 /L
ot l leukocyte count 14.0 × 10 /L
9
A 51-ye r-ol white le construction worker w s t ken

to the e ergency ep rt ent by ellow worker er An incre se in neutrophilic b n s n seg ente neutro-

injuring his wrist t work. On physic l ex in tion, n phils w s observe s well s n incre se in the nu ber o

elev te bloo pressure w s note . No other bnor lities thro bocytes. T e erythrocytic in ices were ll within the

were oun . T e p tient reporte th t he h been i g- nor l r nge.

nose s su ering ro hypertension bout 5 ye rs go. Follow-up testing reve le tot l bloo volu e o 79 L/kg

Te e ergency ep rt ent physici n or ere routine (nor l: ult les, 61.5 ± 8.5 L/kg o bo y weight;

bloo count (CBC), urin lysis, n r iogr ph o the wrist. ult e les, 59.0 ± 5 L/kg) n tot l re cell volu e

o 48 L/kg (nor l: 20 to 36 L/kg o bo y weight). A

■ Laboratory Data urin ry erythropoietin ss y reve le the bsence o e -
He oglobin 21.5 g/ L sur ble erythropoietin in the urine.

He tocrit 64%

(continued)