English 
Italian CASI CLINICI – Case Reports
Volume:
Biochimica Clinica 2019; 43(3) e31-e35
Pubblicato on-line:
July 4, 2019
DOI:
DOI: 10.19186/BC_2019.054
La ricerca degli anticorpi anti-nucleo non è sempre di facile interpretazione
AUTORI
1Unità Operativa Complessa Patologia Clinica Azienda Sanitaria Unica Regionale Marche - Area Vasta 5, Ascoli Piceno
2Servizio Regionale di Immunologia Clinica e Tipizzazione Tessutale, Azienda Ospedali Riuniti di Ancona
3Dipartimento di Scienze Cliniche e Molecolari, Università Politecnica delle Marche
ABSTRACT
Anti-nucleus antibodies detection is not always easy to interpret
Antinuclear antibodies (ANA) displaying densefine speckled pattern on HEp-2/HEp-2000 cells are frequently observed in clinical laboratory, often associated withanti-DFS70 antibodies. Anti-DFS70 positive patients rarely develop systemic autoimmune rheumatic disease,especially in the absence of clinical evidence or additional antibodies.
A 60-years old woman complaining severe muscle weakness of the legs was tested positive for dense fine speckledANA pattern by indirect immune-fluorescence. Immunoblot analysis revealed the presence of anti-DFS70 antibodies.Positivity for anti-dsDNA antibodies, not revealed by immunoblot, was also found by Crithidia luciliae(CL). All theresults were confirmed by a different laboratory.
This case underlines the complex interpretation of a laboratory scenario where anti-DFS70 possibly coexist with muchmore specific and clinically relevant ANA. The discrepancies (observed in both laboratories) between CL and theother methods is puzzling, and may be due to different reasons, including false positive CL results or interference.