Indications:
Balance sheet of connective.
Sample:
Venous blood clotted.
Typical values:
These antibodies are not present in normal subjects.
Interpretation:
Anti-ENA antibodies:
Anti-Sm antibodies:
The anti-Sm antibodies (discovered for the first time in a patient named Smith) is very specific for systemic lupus erythematosus (SLE), but it is observed in 30% of cases.
When it exists, it ensures the diagnosis.
RNP antibodies:
The anti-RNP antibody directed against ribonucleoprotein (RNP) nuclear, is suggestive of a MCTD (or MCTD) when present at high titer.
It is also observed in 30 to 40% of lupus and 10 to 20% of Sjogren’s syndrome.
Anti-SSA (or anti-Ro) antibody and anti-SSB (or anti-La):
The anti-SSA antibody (anti-Ro) and / or anti-SSB antibodies (or anti-La) are specific for Sjögren’s syndrome where they are found in about 90% of cases by ELISA.
The anti-SSA is also present in SLE (30% of cases).
Antihistones antibodies:
Antihistones antibodies can detect lupus induced by drugs (isoniazid, hydralazine, hydantoins, procainamide, etc.):
• a high titer of histone antibodies, contrasting with low titer or no anti-dsDNA antibodies, lupus drug recalls;
• conversely, the absence of antibody antihistones exclude the diagnosis of drug-induced lupus.
Some antinuclear antibodies:
Type Meaning
Lupus anti dsDNA
Lupus drug antihistones so isolated
Anti-Sm Lupus
RNP Lupus
Sjögren’s syndrome
Anti-SSA (anti-Ro) Sjögren’s syndrome
Anti-SSB (anti-La) Sjögren’s syndrome