RT Journal Article SR Electronic T1 Anti-Ku antibodies in connective tissue diseases: clinical and serological evaluation of 14 patients. JF The Journal of Rheumatology JO J Rheumatol FD The Journal of Rheumatology SP 1393 OP 1397 VO 29 IS 7 A1 Franco Franceschini A1 Ilaria Cavazzana A1 Daniele Generali A1 Marzia Quinzanini A1 Luigi Viardi A1 Anna Ghirardello A1 Andrea Doria A1 Roberto Cattaneo YR 2002 UL http://www.jrheum.org/content/29/7/1393.abstract AB OBJECTIVE: To assess the clinical and serological associations of anti-Ku antibodies. METHODS: Fourteen patients with anti-Ku antibody detected by counterimmunoelectrophoresis (CIE) and immunoblot (IB) were retrospectively evaluated. RESULTS: Patients (13 women, one man) had a mean age of 60.3 years (range 19-83). Seven patients had overlap syndromes: 5 polymyositis/scleroderma (PM/SSc), one systemic lupus erythematosus (SLE)/SSc/PM, and one SLE/PM. Three additional patients had undifferentiated connective tissue disease, 2 primary Sjögren's syndrome (SS), one psoriatic arthritis, and one SSc. The clinical manifestations most frequently recorded were arthralgias (86%), myositis (50%) and Raynaud's phenomenon (78.6%). Five patients had esophageal dysmotility, while 6 showed interstitial pulmonary fibrosis (4 of them with reduced DLCO). No case of pulmonary hypertension was observed. All patients had very high titer of ANA with speckled and nucleolar pattern. All the sera were positive for anti-Ku antibodies by CIE: all but one were confirmed by IB. Eight sera contained isolated antibodies to Ku proteins: both subunits were recognized in 7 cases, while isolate reactivity to the 70 kDa protein was detected in one case. Five sera contained additional antibody specificities: anti-Ro 60 kDa in 4 cases, and anti-La/SSB, anti-SL, and anti-PM-Scl in one case each. CONCLUSION: Anti-Ku antibody is found in a wide spectrum of connective tissue diseases including overlap syndromes with SSc and myositis. Raynaud's phenomenon and muscular and joint involvement are the most frequent clinical features associated with anti-Ku antibodies, which are frequently detected in association with anti-Ro/SSA and/or other antinuclear specificities.