Anti ds DNA antibody is specific for: (PGI May 2010)

Ans. A (SLE) Anti-dsDNA 70DNA (double- stranded)High titers are SLE-specific and in some patients correlate with disease activity, nephritis, vasculitisHigh-titer IgG antibodies to double-stranded DNA and antibodies to the Sm antigen are both specific for SLE and, therefore, favor the diagnosis in the presence of compa tible clinical manifestationsTable (Harrison); Diagnostic Criteria for Systemic Lupus ErythematosusMalar rashFixed erythema, flat or raised, over the malar eminencesDiscoid rashErythematous circular raised patches with adherent keratotic scaling and follicular plugging; atrophic scarring may occurPhotosensitivityExposure to ultraviolet light causes rashOral ulcersIncludes oral and nasopharyngeal ulcers, observed by physicianArthritisNonerosive arthritis of two or more peripheral foints, with tenderness, swelling, or effusionSerositisPleuritis or pericarditis documented by ECG or rub or evidence of effusionRenal disorderProteinuria >0.5g/dQ or >3+ or cellular castsNeurologic disorderHematologicdisorderSeizuresQ or psychosis without other causesHemolytic anemia or leukopenia (<4000/ mL) Q or lymphopenia' (<1500/pL) or thrombocytopenia (<100,000/mL) Q in the absence of offending drugsImmunologicdisorderAntinuclearantibodiesAnti-dsDNAQ anti-Sm, and/or antiphospholipidAn abnormal titer of ANAQ by immunofluorescence or an equivalent assay at any point in time in the absence of drugs known to induce ANAsTable (Harrison): Antinuclear Antibody (ANA) Patterns and Clinical AssociationsANA PatternAntigen IdetifiedClinical CorrelateDiffuseDeoxyribonucle - oproteinNonspecific HistonesQDrug-induced lupus,Peripheral (rim)ds-DNA50% of SLE (specific)SpeckledUl-RNP>90% ofMCTD Sm30% of SLE (specific) Ro (SS-A) QSjogrens 60%, SCLE, neonatal lupus, ANA (-) lupus La (SS-BQ50% ofSjogrens, 15% lupus Scl-7040% of diffuse sclerodermaQ PM-1Polymyositis (PM), dermatomyositis Jo-1PM w/ pneumonitis + arthritisNucleolarRNA polymerase 1, others40% ofPSSCentromereKinetochone75% CRESTflimited scleroderma)