The Clinical Spectrum of Antinuclear Antibodies Associated with the Nuclear Dense Fine Speckled Immunofluorescence Pattern

ALESSANDRA DELLAVANCE, VILMA S.T. VIANA, ELAINE P. LEON, ELOISA S.D.O. BONFA, LUÍS E.C. ANDRADE, and PAULO G. LESER

ABSTRACT.

Objective. Autoantibodies to lens epithelium-derived growth factor (LEDGF) depict a distinctive nuclear dense fine speckled (DFS) pattern in the indirect immunofluorescence antinuclear antibody assay (IIF-ANA). Definition of the clinical spectrum associated with anti-LEDGF antibodies has been evolving over the last decade. We investigated the frequency, clinical spectrum, and immunologic specificity of the DFS pattern in a general clinical laboratory routine.

Methods. All serum samples entered for IIF-ANA determination within a 2 year period were examined for the DFS pattern. Positive samples with consistent clinical information were studied further by IIF with isotype-specific conjugate and immunoblot analysis.

Results. Among 13,641 ANA-positive samples, 5081 (37%) presented the DFS pattern. Within a 6 month nested period, there were 650 samples with DFS pattern, and consistent clinical data were available for 81 of these. DFS reactivity was mainly due to IgG. Most samples (86%) presented titer ≥ 1/640. Eighty of the 81 DFS samples reacted with a 75 kDa band that comigrated with the band elicited by the standard anti-LEDGF serum. Antibodies that were affinity-purified from the 75 kDa band reproduced the DFS pattern on IIF-ANA. The clinical spectrum associated with DFS reactivity included autoimmune diseases (39%) and an array of nonautoimmune conditions (61%). Among the autoimmune patients, over half presented evidence of autoimmune thyroiditis.

Conclusion. Anti-LEDGF/p75 antibodies are a common finding among ANA-positive individuals with no evidence of rheumatic autoimmune disease, and should be regarded as a low specificity finding even when in moderate or high titer. (J Rheumatol 2005;32:2144-9)

Key Indexing Terms:

ANTINUCLEAR ANTIBODIES
AUTOANTIBODIES
AUTOANTIGENS
AUTOIMMUNITY

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From the Fleury Research Institute; Rheumatology Division, Universidade de São Paulo; and Rheumatology Division, Universidade Federal de São Paulo, São Paulo, Brazil.

Supported in part by Research Funds of the Brazilian Society of Rheumatology.

A. Dellavance, MSc; P.G. Leser, MD, PhD, Fleury Research Institute; V.S.T. Viana, MSc; E.P. Leon, MSc; E.S.D.O. Bonfa, MD, PhD, Rheumatology Division, Universidade de São Paulo; L.E.C. Andrade, MD, PhD, Rheumatology Division, Universidade Federal de São Paulo.

Address reprint requests to Dr. P.G. Leser, Fleury Research Institute, Rua Gal. Waldomiro de Lima 508, São Paulo, SP, 04344-171, Brazil. E-mail: Paulo.leser@fleury.com.br

Accepted for publication June 27, 2005.

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