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 > or = 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.
Subject(s)
Antibodies, Antineutrophil Cytoplasmic/immunology , Fluorescent Antibody Technique, Indirect/methods , Rheumatic Diseases/diagnosis , Rheumatic Diseases/immunology , Adaptor Proteins, Signal Transducing/immunology , Antibodies, Antineutrophil Cytoplasmic/isolation & purification , Antibody Specificity , Carcinoma, Hepatocellular , Cell Nucleus/immunology , HeLa Cells , Humans , Liver Neoplasms , Transcription Factors/immunologyABSTRACT
Paciente de sexo femenino, de 26 años de edad, con antecedentes de rinitis y cuadros de obstrucción bronquial estacionales que presentó cuadro de úlceras en extremidades inferiores, asociadas a compromiso pulmonar en base a hemoptisis e imágenes radiológicas anormales transitorias, eosinofilia al frotis de sangre periférico y c-ANCA positivo y que responde favorablemente a la terapia con corticoides e inmunosupresores