Table 2

Clinical characteristics of anti-Ku patients with versus without increased CK and with versus without anti-DNA

Increased CK
(atfirst evaluation)
Anti-dsDNA
(atfirst evaluation)
Yes,n=15(%)No,n=27(%)P valueYes,n=10(%)No,n=32(%)P value
Demographic data
 Age, years (range)49.2 (22.6–73.0)30.6 (11.3–74.61.018.0 (11.3–68.1)48.1 (17.5–74.6)1.0
 Sex (F/M)13/222/51.09/126/61.0
 Geographical origin (Caucasia/Africa)11/420/71.07/324/81.0
Organ involvements (ever)
 Increased CK2 (20)13 (40)1.0
 ILD* 12 (80) 1 (4) < 0.001 1 (10)12 (38)1.0
 Arthralgia12 (80)23 (85)1.010 (100)25 (78)1.0
 Raynaud’s phenomenon9 (60)9 (33)1.03 (30)15 (47)1.0
 Muscle weakness 8 (53) 0 0.0074 2 (20)6 (19)1.0
 Dysphagia6 (40)00.221 (10)5 (16)1.0
 Sclerodactyly2 (13)01.002 (6)1.0
 Skin thickening proximal to the MCP1 (7)01.001 (3)1.0
 Telangiectasia2 (13)01.002 (6)1.0
 Mechanic's hand3 (20)01.01 (10)2 (6)1.0
 Lupus rash1 (7)8 (30)1.0 8 (80) 1 (3) < 0.001
 Thrombosis5 (33)4 (15)1.03 (30)6 (19)1.0
 Myocarditis1 (7)01.001 (3)1.0
 Neuropathy1 (7)3 (11)1.03 (30)1 (3)1.0
 Serositis2 (13)6 (22)1.04 (40)4 (13)1.0
 Glomerulonephritis†2 (13)8 (30)1.0 8 (80) 2 (6) < 0.001
 Cytopenia3 (20)10 (37)1.0 9 (90) 4 (13) < 0.001
Autoantibodies (ever)
 Anti-dsDNA‡2 (13)8 (30)1.0---------
 Anti-SSA/Ro605 (33)8 (30)1.04 (40)9 (28)1.0
 Anti-SSB/La03 (11)1.01 (10)2 (6)1.0
 Anti-Sm02 (7)1.02 (20)01.0
 Anti-RNP05 (19)1.04 (40)1 (3)0.16
 Rheumatoid factor5 (33)8 (30)1.0013 (41)0.60
 ACPA2 (13)3 (11)1.01 (10)4 (12)1.0
 Antiphospholipid biology§1 (7)6 (22)1.05 (50)2 (6)0.33
Matched CTD criteria (at last follow-up)
 Myositis 10 (67) 0 < 0.001 2 (20)8 (25)1.0
 SLE1 (7)7 (26)1.0 8 (80) 0 0.001
 MCTD05 (19)1.04 (40)1 (3)0.16
 SS¶4 (27)11 (41)1.02 (20)13 (41)1.0
 pSS2 (13)9 (33)1.0011 (34)1.0
 SSc2 (13)01.002 (6)1.0
 RA1 (7)3 (11)1.004 (12)1.0
 APLS**1 (7)3 (11)1.02 (20)2 (6)1.0
 UCTD1 (7)6 (22)1.007 (22)1.0
  • Statistically significant results are in bold.

  • *CT scan patterns were NSIP (n=8), UIP (n=2), OP (n=2); median vital capacity was 66% (range 20–124) and transfer factor of the lung for carbon monoxide was 57% (range 15–94).

  • †Kidney biopsy (available in eight patients) revealed lupus glomerulonephritis class IV (n=5), extracapillary glomerulonephritis (n=2) and proliferative glomerulonephritis (n=1).

  • ‡The titre of anti-dsDNA was 146 UI/L (56–300).

  • §Antiphospholipid biology consisted of the presence of one or more of the following laboratory criteria, on two or more occasions, at least 12 weeks apart: titre of anticardiolipin antibodies (IgG and/or IgM isotype)>40 GPL or MPL (n=4); anti-β2GPI antibodies (IgG and/or IgM isotype)>40 GPL or MPL (n=1) and/or lupus anticoagulant activity (n=4).

  • ¶Patients with sSS were listed both by sSS and by their primary connective tissue disease.

  • **APLS was secondary in all cases (no patient had primary antiphospholipid syndrome).

  • ACPA, anticitrullinated peptide antibodies; APLS, antiphospholipid syndrome;CK, creatine kinase; ILD, interstitial lung disease; MCTD, mixed connective tissue disease;pSS, primary Sjögren’s syndrome; RA, rheumatoid arthritis; table 1 for other abbreviations.RNP, ribonucleoprotein; sSS, secondary Sjögren’s syndrome;SS, Sjögren's syndrome; SLE, systemic lupus erythematosus; SSc, systemic sclerosis;UCTD, undifferentiated connective tissue disease.