title: Diagnostic accuracy of two tests for determination of anti-m2 in the diagnosis of primary biliary cirrhosis: Is it possible to predict the course of the disease?
abstract: To evaluate the analytical agreement between results obtained from the indirect immunofluorescence methods and from the multiplexed line-blot assay and EliA-M2, to analyze the diagnostic accuracy in a cohort of primary biliary cirrhosis (PBC) patients and in control patients of two different types of tests for anti-M2 and assess whether, with the advent of a quantitative test, the possibility exists to correlate disease activity with the value of AMA. Serum analysis of 67 patients with fluorescence patterns detected on Hep-2 cells suggestive of PBC-related antibodies and three groups of patients (15 PBC, 16 PBC suspect and 48 disease controls) was carried out. All samples were tested by both a qualitative test multiplexed line-blot Autoimmune Liver Disease Profile Euroline and by a quantitative test EliA-M2 IgG. In order to evaluate a possible correlation between the quantitative M2 and disease activity, we divided patients mixed in a further three groups based on the value EliA-M2. For each of these groups were calculated the average values of the main indices of cholestasis. A perfect agreement was shown between the EliA-M2 and the multiplexed line-blot method for AMA detection. All sera of patients with PBC were positive with both tests, with a 100 % sensitivity. Forty-seven of the 48 sera of the control group were negative for both tests with a 100 % next specificity, and only 70 % for the AMA-IIF. We had also observed in the other three groups of patients that the average of the values of γ-glutamyl transpeptidase and alkaline phosphatase increases with the increase of the value EliA-M2. The difference between the mean values of the most significant parameter which the alkaline phosphatase of the three groups is significant, with a statistically significant difference between the first and the third group (p value 0.023). Both the qualitative method Profile Euroline and the quantitative EliA-M2 have a high diagnostic accuracy for PBC, with a specificity higher than the immunofluorescence method. These preliminary data might suggest the possibility of using the dosage EliA-M2 not only in the diagnosis phase but also in the monitoring of disease activity.
authors.affiliation: Clinical Pathology, Hospital ASL TO4, Via Battitore 2, 10073, Ciriè, TO, Italy. antonioalfano@libero.it.
authors.forename: Antonio Maria
authors.initials: AM
authors.lastname: Alfano
authors.affiliation: Analysis Laboratory, Hospital Maria Vittoria ASL TO2, Turin, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Romito
authors.affiliation: Analysis Laboratory, A.O. Ordine Mauriziano, Turin, Italy.
authors.forename: Cristiana
authors.initials: C
authors.lastname: Marchese
authors.affiliation: Clinical Pathology, Hospital ASL TO4, Via Battitore 2, 10073, Ciriè, TO, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Battistini
authors.affiliation: Clinical Pathology, Hospital ASL TO4, Via Battitore 2, 10073, Ciriè, TO, Italy.
authors.forename: Giliola
authors.initials: G
authors.lastname: Crotti
authors.affiliation: Clinical Pathology, Hospital ASL TO4, Via Battitore 2, 10073, Ciriè, TO, Italy.
authors.forename: Arturo
authors.initials: A
authors.lastname: Ferrini
authors.affiliation: Clinical Pathology, Hospital ASL TO4, Via Battitore 2, 10073, Ciriè, TO, Italy.
authors.forename: Cristina
authors.initials: C
authors.lastname: Mancinetti
authors.affiliation: Biochimical Laboratory, A.O.U. Città Della Salute E Della Scienza, Turin, Italy.
authors.forename: Tilde
authors.initials: T
authors.lastname: Manetta
authors.affiliation: Biochimical Laboratory, A.O.U. Città Della Salute E Della Scienza, Turin, Italy.
authors.forename: Giulio
authors.initials: G
authors.lastname: Mengozzi
authors.affiliation: Clinical Pathology, Hospital ASL TO4, Via Battitore 2, 10073, Ciriè, TO, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Merlach
authors.affiliation: Analysis Laboratory, A.O. Ordine Mauriziano, Turin, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Migliardi
authors.affiliation: Clinical Pathology, Hospital ASL TO4, Via Battitore 2, 10073, Ciriè, TO, Italy.
authors.forename: Maria Teresa
authors.initials: MT
authors.lastname: Tambuzzo
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001323:Autoantibodies / Q000097:blood*; D045744:Cell Line, Tumor; D005260:Female; D006801:Humans; D007159:Immunologic Tests; D008105:Liver Cirrhosis, Biliary / Q000097:blood / Q000175:diagnosis* / Q000276:immunology; D008297:Male; D008875:Middle Aged; D008928:Mitochondria / Q000276:immunology*; D012680:Sensitivity and Specificity
chemical_list: D001323:Autoantibodies
keywords: Anti-mitochondrial antibodies; Antinuclear PBC-correlated antibodies; Indirect immunofluorescence microscopy; Primary biliary cirrhosis; Prognosis; Solid phase methods