This is an approach to the basis of the common antibodies and the associated diseases, called autoimmune diseases.

1. Approach to connective tissue disease

2. • Prototype is SLE
• Overlap of symptoms and signs occur
• Labs are not always conclusive

3. Approach
• Labs cant diagnose certainly
• Clue to disease
ANA-
nucleotides and nucleoproteins
• Used to screen CTD
• Except Rheumatic Arthritis – high sensitivity but
low specificity

4. Positive ANA without CTD
• Aging , HIV , viral hepatitis, ILD, Tuberculosis
• Malignancies – B cell lymphomas
• If negative ANA- chance of CTD is very low
except rheumatoid arthritis

5. Specific antibodies
Antids DNA
Against double stranded DNA
Specific for SLE especially lupus nephritis
Titres for monitoring process of damage

6. SSA/Ro
• Sjogrens syndrome
• SLE associated with photosensitivity
• Neonatal lupus
• Fetal congenital heart block in mothers with
SLE

7. SSB/La
• Also seen in Sjogren’s syndrome
• SSA/Ro + SSB/La- definitive diagnosis of the
Sjogrens syndrome

8. RNP-U1
• Ribonucleoprotein U1
• Seen in mixed connective tissue
disease(MCTD)
• Lupus , scleroderma and myositis

9. AntiScl 70
• Scleroderma 70 ( antitopoisomerase 1 )
• Seen in systemic sclerosis
• Increased risk of ILD in systemic sclerosis
patients with AntiScl 70

10. Anticentromere antibodies
CREST syndrome
- Calcinosis cutis
- Raynaud’s syndroome
- Esophageal dysmotility
- Sclerodactily
- Telengectasia

11. Antihistone antibodies
• It is a ribonucleoprotein
• Drug induced SLE
- Procanamide
- INH
- Hydralazine
- Quinidine --------moderate risk

12. Anti-Jo 1 antibody
• Seen in antisynthetase syndrome
(Polmyositis and ILD)

13. Rheumatoid factor(RF)
• Seen in RA and Hep C
• IgM against Fc portion of IgG

14. Anti-CCP antibody
• Cyclic citrulinated antibody
• Derivative of arginine
• Seen in rheumatoid arthritis

15. CRP
• Non specific for inflammation
• Acute phase reactant from liver
• Varies with level of inflammation
• Produced on the signal of IL-6

16. ESR
• Proportional to inflammation
• False elevation can occur
• Not specific

17. Thank you