Page 624 - Clinical Hematology_ Theory _ Procedures ( PDFDrive )

608 PART 8 ■ Fundamentals of Hematological Analysis

With a red compensator, CPPD crystals appear blue when the

longitudinal axis is parallel to the slow component o the com- TABLE 29.17 Classi cation of Synovial Fluid

pensator. T ey exhibit positive bire ringence. CPPD crystals

are yellow when perpendicular to the axis o the compensator. Group Description

CPPD crystals are associated with CPPD deposition disease.

However, they may be identi ed in e usions rom a number o I Nonin ammatory

inf ammatory joint diseases, particularly rheumatoid arthritis. II In ammatory

Cholesterol Crystals III Infectious

Cholesterol crystals are usually easy to distinguish because o IV Crystal induced
their large size and f at, plate-like shape. Characteristically, V Hemorrhagic

these rectangular plates have notched corners. T ey may,
however, appear as long, bire ringent needles or as rhom-

boids, resembling MSU or CPPD crystals. the traditional push method. T is method has the advantage
T e presence o cholesterol crystals is considered to be o requiring no special equipment, but the recovery o cells

nonspeci c. However, they are usually ound in chronic e u- is variable and a considerable amount o cellular damage is
sions rom patients with rheumatoid arthritis. produced.

More e ective methods o concentrating cells include

Arti acts sedimentation, cytocentri ugation, and ltration.

Artifacts can be mistaken or crystals, although crystals have

sharp, clearly de ned edges and straight sides. Particulate Staining of Body Fluid Sediment

matters that can be con used with crystals include plastic

joint prostheses, nail polish, dust particles, immersion oil Morphological descriptions o cells encountered in body

droplets, and re ractile collagen brils. f uids ref ect their microscopic appearance with Wright

CPPD and MSU crystals can be con used with other bire- or Wright-Giemsa stain. T e coloration o cells with

ringent materials including crystalline anticoagulants, such Papanicolaou’s stain ( able 29.18) is somewhat di erent.

as calcium oxalate, ethylenediaminetetraacetic acid (ED A), However, the Papanicolaou’s stain is a commonly used cyto-

and lithium heparin; certain corticosteroid preparations; and logical stain. Tis procedure, in CLSI ormat, is provided on this

talcum powder. book’s companion Web site at thepoint.lww.com/ urgeon6e.
Te Wright-Giemsa stain is basically a cytoplasmic stain

Clinical Applications with moderate nuclear staining ability. In contrast, the
Papanicolaou’s stain is predominantly a nuclear stain with a
T e distinction between various types o arthritis is not always

easy to make based on clinical observations. raditionally, modest ability or cytoplasmic di erentiation. T e Wright-

synovial f uids have been classi ed into several categories Giemsa staining method is simpler than the Papanicolaou

( ables 29.16 and 29.17) based on gross appearance, total method because it requires no immediate xation o the

leukocyte and di erential cell counts, and physical and slide and there ore ewer steps in the staining procedure.

chemical examinations. However, a di erence in cell size is evident between the two
staining protocols. Cells appear larger when prepared by the

Body Fluid Slide Preparation air-dried, Wright-Giemsa procedure. It is most help ul, i

possible, to prepare and stain specimens by both methods to
A di erential cell count on a body f uid should be per ormed gain as much in ormation as possible. T e criteria or diag-

on stained smears prepared rom a concentrated prepara- nosis are exactly the same or normal or abnormal cells by

tion—not in a hemacytometer. Some o the techniques o either method.

sediment preparation and staining are di erent or body f uids

than or blood. T e procedure, in CLSI ormat, is provided on

this book’s companion Web site at thepoint.lww.com/ urgeon6e. Amniotic Fluid

Ordinary centri ugation can be used to concentrate cellu- Amniotic uid is the nourishing and protecting liquid con-

lar elements in the sediment, and slides can be prepared with tained by the amnion o a pregnant woman. It consists o

mostly water but also contains proteins, carbohydrates, lipids

and phospholipids, urea, and electrolytes, all o which aid in

Comparison of In ammatory and the growth o the etus. In the late stages o gestation, most o
TABLE 29.16
Nonin ammatory Synovial Fluids the amniotic f uid consists o etal urine.

T e volume o amniotic f uid increases until about
Total WBC % Polymorphonuclear 34 weeks o gestation, at which time the amount o amniotic

Category Count Segmented Neutrophils f uid is about 800 mL and is reduced to about 600 mL at the

time o birth (about 40 weeks).
In ammatory >2 × 10 /L >75%
9
Amniotic f uid is continually being swallowed and
9
Nonin ammatory <2 × 10 /L <75% “inhaled” and replaced through being “exhaled.” It is essential