Is anti-topoisomerase I a serum marker of pulmonary involvement in systemic sclerosis?
OBJECTIVE
To determine the value of the level of anti-topoisomerase I (anti-topo I) to evaluate lung involvement defined by abnormal high-resolution computed tomography (HRCT) score and pulmonary function tests (PFTs) in systemic sclerosis (SS).


METHODS
Forty-eight patients with SS, 20 with lung involvement and 28 with no lung involvement.


METHODS
PFT measurement, HRCT scoring of lung involvement, and anti-topo I assay by enzyme-linked immunosorbent assay. Normal anti-topo I level was defined as < 30.


RESULTS
There was a significant association between cutaneous extent and anti-topo I level (6.5% of patients with limited cutaneous scleroderma had abnormal anti-topo I levels vs 70.6% of patients with diffuse cutaneous scleroderma, p = 0.0001). In patients with diffuse cutaneous scleroderma, pulmonary involvement was associated with a higher percentage of abnormal anti-topo I level: 91.7% vs 20% (p = 0.010). In patients with diffuse cutaneous scleroderma, a significant association was found between the class of anti-topoII level and total lung capacity (median, 69 in patients with abnormal anti-topo I level vs 87 in patients with normal anti-topo I level, p = 0.010), between the class of anti-topo I level and HRCT score (median, 12 in patients with abnormal anti-topo I level vs 5 in patients with normal anti-topo I level, p = 0.05).


CONCLUSIONS
Anti-topo I can be considered as a marker of lung involvement in patients with diffuse cutaneous scleroderma.
Diot
E
E
Groupe de Recherche Epithélium Respiratoire et Inflammation, Service de Médecine Interne B, CHU Bretonneau, Tours, France.
Giraudeau
B
B
Diot
P
P
Degenne
D
D
Ritz
L
L
Guilmot
J L
JL
Lemarié
E
E
D000328:Adult; D000368:Aged; D000974:Antibodies, Antinuclear / Q000097:blood*; D001323:Autoantibodies / Q000097:blood; D015415:Biomarkers / Q000097:blood*; D002503:Centromere / Q000276:immunology; D004264:DNA Topoisomerases, Type I / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging; D017563:Lung Diseases, Interstitial / Q000150:complications / Q000175:diagnosis* / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D012129:Respiratory Function Tests; D012595:Scleroderma, Systemic / Q000150:complications / Q000175:diagnosis / Q000276:immunology*; D014057:Tomography, X-Ray Computed
D000974:Antibodies, Antinuclear; D001323:Autoantibodies; D015415:Biomarkers; D004264:DNA Topoisomerases, Type I