Laboratory Values of Clinical Importance (Rheumatology) Part 1

ANALYTE

SPECIMEN^a

SI UNITS

CONVENTIONAL UNITS

Activated clotting time

WB

70-180 s

70-180 seconds

Activated protein C resistance

P

Not applicable

Ratio > 2.1

(factor V Leiden)

Alpha₂ antiplasmin

P

0.87-1.55

87-155%

Antiphospholipid antibody panel

PTT-LA (lupus anticoagulant screen)

P

Negative

Negative

Platelet neutralization procedure

P

Negative

Negative

Dilute viper venom screen

P

Negative

Negative

Anticardiolipin antibody

S

IgG

0-15 arbitrary units

0-15 GPL

IgM

0-15 arbitrary units

0-15 MPL

Antithrombin III

P

Antigenic

220-390 mg/L

22-39 mg/dL

Functional

0.7-1.30 U/L

70-130%

Anti-Xa assay (heparin assay)

P

Unfractionated heparin

0.3-0.7 kIU/L

0.3-0.7 IU/mL

Low-molecular-weight heparin

0.5-1.0 kIU/L

0.5-1.0 IU/mL

Danaparoid (Orgaran)

0.5-0.8 kIU/L

0.5-0.8 IU/mL

Autohemolysis test

WB

0.004-0.045

0.4%-4.50%

Autohemolysis test with glucose

WB

0.003-0.007

0.3%-0.7%

Bleeding time (adult)

<7.1 min

<7.1 min

Bone marrow: see Table A-8

Clot retraction

WB

0.50-1.00/2 h

50-100%/2 h

Cryofibrinogen

P

Negative

Negative

D-Dimer

P

0.22-0.74 μg/mL

0.22-0.74 μg/mL

Differential blood count

WB

Neutrophils

0.40-0.70

40-70%

Bands

0.0-0.05

0-5%

Lymphocytes

0.20-0.50

20-50%

Monocytes

0.04-0.08

4-8%

Eosinophils

0.0-0.6

0-6%

Basophils

0.0-0.02

0-2%

Eosinophil count

WB

150-300^L

150-300/mm³

Erythrocyte count

WB

Adult males

4.30-5.60 X 10¹²/L

4.30-5.60 X 10⁶/mm³

Adult females

4.00-5.20 X 10¹²/L

4.00-5.20 X 10⁶/mm³

Erythrocyte life span

WB

Normal survival

120 days

120 days

Chromium labeled, half life (t_1/2)

25-35 days

25-35 days

Erythrocyte sedimentation rate

WB

Females

0-20 mm/h

0-20 mm/h

Males

0-15 mm/h

0-15 mm/h

Euglobulin lysis time

P

7200-14400 s

120-240 min

Factor II, prothrombin

P

0.50-1.50

50-150%

Factor V

P

0.50-1.50

50-150%

Factor VII

P

0.50-1.50

50-150%

Factor VIII

P

0.50-1.50

50-150%

Factor IX

P

0.50-1.50

50-150%

Factor X

P

0.50-1.50

50-150%

Factor XI

P

0.50-1.50

50-150%

Factor XII

P

0.50-1.50

50-150%

Factor XIII screen

P

Not applicable

Present

ANALYTE

SPECIMEN^a

SI UNITS

CONVENTIONAL UNITS

Factor inhibitor assay

P

<0.5 Bethesda Units

<0.5 Bethesda Units

Fibrin (ogen) degradation products

P

0-1 mg/L

0-1 μg/mL

Fibrinogen

P

2.33-4.96 g/L

233-496 mg/dL

Glucose-6-phosphate dehydrogenase

WB

<2400 s

<40 min

(erythrocyte)

Ham’s test (acid serum)

WB

Negative

Negative

Hematocrit

WB

Adult males

0.388-0.464

38.8-46.4

Adult females

0.354-0.444

35.4-44.4

Hemoglobin

Plasma

P

6-50 mg/L

0.6-5.0 mg/dL

Whole blood

WB

Adult males

133-162 g/L

13.3-16.2 g/dL

Adult females

120-158 g/L

12.0-15.8 g/dL

Hemoglobin electrophoresis

WB

Hemoglobin A

0.95-0.98

95-98%

Hemoglobin A₂

0.015-0.031

1.5-3.1%

Hemoglobin F

0-0.02

0-2.0%

Hemoglobins other than A, A₂, or F

Absent

Absent

Heparin-induced thrombocytopenia antibody

P

Negative

Negative

Joint fluid crystal

JF

Not applicable

No crystals seen

Joint fluid mucin

JF

Not applicable

Only type I mucin present

Leukocytes

Alkaline phosphatase (LAP)

WB

0.2-1.6 μkat/L

13-100 μ/L

Count (WBC)

WB

3.54-9.06 X 10⁹/L

3.54-9.06 X 10³/mm³

Mean corpuscular hemoglobin (MCH)

WB

26.7-31.9 pg/cell

26.7-31.9 pg/cell

Mean corpuscular hemoglobin concentration (MCHC)

WB

323-359 g/L

32.3-35.9 g/dL

Mean corpuscular hemoglobin of reticulocytes (CH)

WB

24-36 pg

24-36 pg

Mean corpuscular volume (MCV)

WB

79-93.3 fL

79-93.3 μm3

Mean platelet volume (MPV)

WB

9.00-12.95 fL

9.00-12.95 μm3

Osmotic fragility of erythrocytes

WB

Direct

0.0035-0.0045

0.35-0.45%

Index

0.0030-0.0065

0.30-0.65%

Partial thromboplastin time, activated

P

26.3-39.4 s

26.3-39.4 s

Plasminogen

P

Antigen

84-140 mg/L

8.4-14.0 mg/dL

Functional

0.70-1.30

70-130%

Plasminogen activator inhibitor 1

P

4-43 μg/L

4-43 ng/mL

Platelet aggregation

PRP

Not applicable

>65% aggregation in response to adenosine diphosphate, epinephrine, collagen, ristocetin, and arachidonic acid

Platelet count

WB

165-415 X 10⁹/L

165-415 X 10³/mm³

Platelet, mean volume

WB

6.4-11 fL

6.4-11.0 μm³

Prekallikrein assay

P

0.50-1.5

50-150%

Prekallikrein screen

P

No deficiency detected

Protein C

P

Total antigen

0.70-1.40

70-140%

Functional

0.70-1.30

70-130%

Protein S

P

Total antigen

0.70-1.40

70-140%

Functional

0.65-1.40

65-140%

Free antigen

0.70-1.40

70-140%

Prothrombin gene mutation G20210A

WB

Not applicable

Not present

ANALYTE

SPECIMEN^a

SI UNITS

CONVENTIONAL UNITS

Prothrombin time

P

12.7-15.4 s

12.7-15.4 s

Protoporphyrin, free erythrocyte

WB

0.28-0.64 μmol/L of red blood cells

16-36 μg/dL of red blood cells

Red cell distribution width

WB

<0.145

<14.5%

Reptilase time

P

16-23.6 s

16-23.6 s

Reticulocyte count

WB

Adult males

0.008-0.023 red cells

0.8-2.3% red cells

Adult females

0.008-0.020 red cells

0.8-2.0% red cells

Reticulocyte hemoglobin content

WB

>26 pg/cell

>26 pg/cell

Ristocetin cofactor (functional von

P

Willebrand factor)

Blood group O

0.75 mean of normal

75% mean of normal

Blood group A

1.05 mean of normal

105% mean of normal

Blood group B

1.15 mean of normal

115% mean of normal

Blood group AB

1.25 mean of normal

125% mean of normal

Sickle cell test

WB

Negative

Negative

Sucrose hemolysis

WB

<0.1

<10% hemolysis

Thrombin time

P

15.3-18.5 s

15.3-18.5 s

Total eosinophils

WB

150-300 X 10⁶/L

150-300/mm³

Transferrin receptor

S, P

9.6-29.6 nmol/L

9.6-29.6 nmol/L

Viscosity

Plasma

P

1.7-2.1

1.7-2.1

Serum

S

1.4-1.8

1.4-1.8

Von Willebrand factor (vWF) antigen

(factor VIII:R antigen)

P

Blood group O

0.75 mean of normal

75% mean of normal

Blood group A

1.05 mean of normal

105% mean of normal

Blood group B

1.15 mean of normal

115% mean of normal

Blood group AB

1.25 mean of normal

125% mean of normal

Von Willebrand factor multimers

P

Normal distribution

Normal distribution

White blood cells: see “leukocytes”