Blood test explanation - Isotypes antibodies

Isotypes of antibodies

Further information: Antibody

Test	Patient	Lower limit	Upper limit	Unit	Comments
IgA	Adult	70,[3] 110[143]	360,[3] 560[143]	mg/dL
IgD		0.5[143]	3.0[143]
IgE		0.01[143]	0.04[143]
IgG		800[143]	1800[143]
IgM		54[143]	220[143]

Autoantibodies

For clinical associations, see Autoantibody.

Autoantibodies are usually absent or very low, so instead of being given in standard reference ranges, the values usually denote where they are said to be present, or whether the test is a positive test. There may also be an equivocal interval, where it is uncertain whether there is a significantly increased level. All included values^[144] are given for the ELISA test.

Test	Negative	Equivocal	Positive	Unit
anti-SS-A (Ro)	< 15[145]	15-25[145]	> 25[145]	Units per millilitre (U/mL)
anti-SS-B (La)	< 3[145]	3 – 4[145]	> 4[145]
Anti ds-DNA	< 40[145]	40 – 60[145]	> 60[145]
Anti ss-DNA	< 8[145]	8 - 10[145]	> 10[145]
Anti-histone antibodies	< 25[145]	n/a[145]	> 25[145]
Cytoplasmic/classical anti-neutrophil cytoplasmic antibodies (c-ANCA)	< 20[145]	21 - 30[145]	> 30[145]
Perinuclear anti-neutrophil cytoplasmic antibodies (p-ANCA)	< 5[145]	n/a	> 5[145]
Anti-mitochondrial antibodies (AMA)	< 10[145]	n/a[145]	> 10[145]
Rheumatoid factor (RF)	< 20	20 - 30	> 30[7]
Antistreptolysin O titre (ASOT) in preschoolers			> 100
ASOT at school age			> 250[7]
ASOT in adults			> 125[7]

Test	Negative	Low/weak positive	Moderate positive	High/strong positive	Unit
Anti-phospholipid IgG	< 20[145]	20 –30[145]	31 – 50[145]	> 51[145]	GPLU/ml[145]
Anti-phospholipid IgM	< 1.5[145]	1.5 –2.5[145]	2 – 9.9[145]	> 10[145]	MPL /ml[145]
Anti-phospholipid IgA	< 10[145]	10 -20[145]	21 – 30[145]	> 31[145]	arb U/ml[145]
Anti-citrullinated protein antibodies	< 20[145]	20 – 39[145]	40 - 59[145]	> 60[145]	EU[145]