History of ANA testing

•The LE cells•In vitro damaged white cells are coated with “LE Factor”•LE factor: a family of antibodies to nuclear constituents•Late 1950’s: many in vitro immuno-fluorscence based tests developed•Titers (>&=1:40 increase in specificity;patterns of immunostaining: change of substrate (Hep-2) brings >increase in sensitivity, now pos if >1:80)•Change of substrate (HEp-2)•Low sensitivity for anti-Ro/SSA antibodies•EIA/ELISA testing=lower cost of testing, easier to perform•Specific auto Abs to nuclear Ags (SSA,SSB, ds-jilDNA)

•Point 2

HISTORY OF ANA TESTING

When should an ANA test be ordered?

When there is a clinical evaluation that has led to a

presumptive diagnosis

CONDITIONS ASSOCIATED WITH POSITIVE ANA TEST

• Very useful– Scleroderma (60-90%) ,SLE (95-100%)

• Somewhat useful– Sjogren’s syndrome (40-70%)

• idiopathic inflammatory myositis (dermato/polymyositis) (30-80%)

CONDITIONS ASSOCIATED WITH+ ANA

• Diseases for which ANA is useful for monitoring /prognosis– Juvenile chronic oligoarticular arthritis with

uveitis– Raynaud’s phenomenon

• Diseases for which a positive ANA test is an intrinsic part of diagnostic criteria– Drug-induced SLE– MCTD

Titer significance

•> 1: 40 = NEGATIVE

•> 1: 80 – 1: 160 = low titer positive

•> 1: 160 = positive, more likely to have autoimmune disease

Diseases for which an ANA test is NOT useful in diagnosis

• Rheumatoid arthritis 30-50%• Multiple sclerosis 10-30%• Thyroid disease 30-50%• Discoid lupus 5-25%• Infectious diseases wide variations• Malignancies wide variations• Patients with silicone breast implants 15-25%• Fibromyalgia 15-25%• Healthy relatives of pts with SLE or

Scleroderma 5-25%

Conditions with +ANA

• Autoimmune disease

• Infectious disease

• Medications

• Epidemiology

• Conditions

• Very High Titers: more likely to have autoimmune disease, but does NOT indicate disease activity

ANA Patterns

• Homogenous chromatin (but homogenous histone is drug related)

• Rim pattern (chromatin 1013& nuclear membrane)

• Fine speckled (nuclear RNP & chromatin..but more common in other CTD)

ANA PATTERNS & ASSOCIATIONS

Homogenous Pattern-also present in 50-70% of SLE

• Anti-Histone: Drug SLE

Nuclear RNP

• Specific for MCTD (100)% of pts with MCTD)

• Also present in 30-40% of SLE

• Assoc with MCTD, overlap SLE, and also DM/PM, and Scleroderma

Speckled

• CREST syndrome (CREST has speckles in the center)

• Anti-Centromere present in 70-85% of pts with limited scleroderma/CREST

• Anti-centromere present in <5% of SLE

• Associated with Raynaud’s phenomena

CYTOPLASMIC/ANTI RIBOSOMAL

• Psychiatric Lupus

AUTOANTIBODY ASSOCIATIONS

• ANA is sensitive

• Anti-Sm and DS-DNA are specific

• ANA in a primary care setting:

• Sensitivity=100%,Specificity=67%

• Negative ANA is useful, however +ANA present in many DX and in normals(5-40%)

Autoantibody specificity: Specific for SLE

• Anti SM ( RNP)

• Present in 30-40% of SLE

• Very uncommon in other diseases

• Associated with Interstitial Lung Disease

• Specificity: Sjogen’s (60-70% of pts with Sjogren’s)

Ro(SSA) and La (SSB).

• Ro present in 25-30% of SLE, La also present in 10-15% of SLE

• Also associated with subacute cutaneous lupus

• Anti-Ro (NOT La): Neonatal lupus with heart block (babies drown from Ro boats)

ANTI-JO-1

• Specificity: present in 40-50% of pts with Polymyositis/Dermatomyositis, especially with pulmonary interstitial disease & arthritis

• Present in < 5% of SLE

SCL-70 (topoismerase 1)

• PSS (Progressive Systemic Sclerosis)

• (40-70% of pts with Diffuse PSS)

When should an ANA test be ordered?

When there is a clinical evaluation that has led to a

presumptive diagnosis

ANA :FAQs• What tests should be performed in young

women with symmetric arthralgias?• A) arthralgias (not arthritis), 6weeks-

NOTHING,CMV,HSV,VZV• VIRUSES frequently-HBV,HAV, HCV<

rubella(vaccine as well), parvo, occasionally, EBV,HIV,mumps,coxsackie,echo,adeno,CMV HSV, VZV

ANA: FAQs• B) arthralgias > 6 weeks or Arthritis-

• Further investigation

ANA : FAQs

• What other testing should be done after a + ANA in an asymptomatic patient?

• NOTHING more……Consider following for 3-5 years?

• What tests should be done in young women with symmetric arthralgias?

• A) arthralgias (not arthritis) < 6 wks- NOTHING• Viruses frequently, HBV, HCV,rubella (vaccine),

parvo, occasionally-EBV,HIV, mumps,

RAMIFICATIONS OF + ANA

• Patients spend the rest of their lives waiting to get sick, still think they are sick, request disability in the absence of any rheumatological disease findings, one person telling them a +ANA implies Lupus seems to outweigh several people telling them there is nothing wrong with them, all symptoms they have the rest of their lives are due “to my Lupus”, which they don’t have