The clinical significance of autoantibodies directed against prothrombin in primary antiphospholipid syndrome.

BACKGROUND: To evaluate the clinical significance of IgG/IgM antibodies directed against prothrombin (PT) in a homogeneous cohort of patients with primary APS (PAPS). METHODS: IgG/IgM anti-prothrombin (aPT) antibodies were measured using a commercial ELISA kit in 158 PAPS patients and in 214 control subjects (100 healthy blood donors and 114 patients with autoimmune diseases). RESULTS: IgG/IgM aPT antibodies were significantly associated with PAPS (OR, 95% CI: 52.0, 7.0-385.5; 9.8, 1.2-80.8, respectively). They were found to have a high specificity (IgG 99.50%, IgM 99.54%) but a low sensitivity (IgG 19.60%, IgM 3.80%) for PAPS. IgG aPT antibodies were significantly higher in the PAPS patients with thrombosis (OR, 95% CI: 69.2, 9.2-519.1) as well as in those with pregnancy morbidity alone (OR, 95% CI: 20.5, 2.4-174.5). The prevalence of IgG aPT was not significantly different in the thrombotic and obstetric patients, and the presence of IgM aPT antibodies was significant only in patients with thrombosis (OR, 95% CI: 2.6, 1.6-110.8). CONCLUSIONS: The study's findings confirm that IgG/IgM aPT antibodies are significantly associated with PAPS and indicate that IgG aPT antibodies are associated with clinical subsets of the disease. For the time being, however, the lower sensitivity of IgG/IgM antibodies with respect to conventional aPL antibodies precludes their inclusion in the recommendations for the diagnosis of PAPS.

Prevalence of coeliac disease in primary biliary cirrhosis and of antimitochondrial antibodies in adult coeliac disease patients in Italy.

BACKGROUND: Although an association between primary biliary cirrhosis and coeliac disease has recently been reported in Northern Europe, there are still conflicting data concerning this issue. AIM: To evaluate both the prevalence of coeliac disease in a series of primary biliary cirrhosis patients and that of antimitochondrial antibodies in a series of adult biopsy proven coeliac disease patients from Northern Italy. PATIENTS AND METHODS: A total of 87 primary biliary cirrhosis patients (79 female, 8 male) were screened for both IgA-transglutaminase antibodies and antiendomysium antibodies and, in those with either IgA-transglutaminase antibodies or antiendomysium antibodies positivity, upper endoscopy with distal duodenum biopsy was offered. In those who refused upper endoscopy, the intestinal permeability test with lactulose/mannitol excretion was performed. RESULTS: Antiendomysium antibodies positivity was detected in 3 subjects (3.4%), all of whom had serum IgA-transglutaminase antibodies above the normal range, and fulfilled the diagnosis of coeliac disease. Of 21 other patients with serum IgA-transglutaminase antibodies above the normal range, 17 underwent upper endoscopy which revealed normal duodenum architecture. The remaining 4 patients underwent the lactulose/mannitol excretion test which was within the normal range. Sera from 108 adult coeliac disease patients were tested for antimitochondrial antibodies and positivity was found in 4 patients (3.7%): all had normal liver biochemistry tests, whereas 2 of them also presented thyroid disease. Antibodies directed to the 74-kDa polypeptide of antimitochondrial antibodies were found in 3 out of 4 antimitochondrial antibodies+ve patients. CONCLUSIONS: These results suggest an association between primary biliary cirrhosis and coeliac disease similar to that observed in the Northern European series. In conclusion, screening for coeliac disease with antiendomysium antibodies in primary biliary cirrhosis is justified, and screening for antimitochondrial antibodies is advisable in adult coeliac disease patients.

Role of anti-transglutaminase (anti-tTG), anti-gliadin, and anti-endomysium serum antibodies in diagnosing celiac disease: a comparison of four different commercial kits for anti-tTG determination.

The aims of this study were: (1) to compare the diagnostic efficacy for celiac disease (CD) diagnosis of serum determination of anti-gliadin (AG) (IgA and IgG) and anti-endomysium (AE) with that of anti-transglutaminase (AtTG); and (2) to compare the accuracy of four different assays to measure AtTG. We studied 72 children: the histological diagnosis of CD was made in 38 cases and excluded in the remaining 34 children. In fasting sera we measured AE, AG-IgA and IgG, and AtTG, the latter with four different commercial kits (Eurospital, Medipan, Inova, Arnika). Moreover AtTG was measured in a group of 58 CD children after a gluten-free diet. AE was positive in all but 1 case of CD patients (sensitivity = 97%); false positive results were found in 1/34 controls (specificity = 97%). When a specificity of 95% was fixed, the sensitivities were 97% for AE, 83% for AG-IgA, and 63% for AG-IgG; the sensitivities of anti-tTG were 90, 84, 84, and 75% when measured with Eurospital, Medipan, Inova, and Arnika kits respectively. The new AtTG seems to be accurate enough to be proposed as a noninvasive diagnostic tool for CD diagnosis; the 4 kits analyzed showed similar diagnostic efficacy.

[Silent celiac disease: results of a study in secondary schools of Padua]. / La celiachia silente: risultati di uno studio nelle scuole medie di Padova.

Aim of this study was the assessment of the prevalence of coeliac disease (CD) in children attending the secondary school in the city of Padua. 939 students, aged 10-15 years (mean age: 12 years, 7 months), 35% eligible population, were accepted to undergo a study process which included three stages: a) in all students venous sample was taken for measurement of the IgG and IgA anti-gliadin antibodies (AGA); b) measurement of serum immunoglobulins and anti-endomysium antibodies (AEA) if AGA IgA was resulted positive; c) intestinal biopsy was performed in 3 students; two of them had pathologic levels of AGA IgG and IgA and AEA. These patients were females and had decreased rates of statural growth, anemia with iron deficiency, anorexia, abdominal pain, asthenia. The third girl had positive AGA IgG and IgA but absence of AEA and normal biopsy. She also had symptoms of abdominal pain, reduced height. Follow-up studies have been planned to establish a latent phase of CD. In conclusion, the prevalence of CD was 2.13/1000 (0.37-8.55, 95% CI), if we consider the patients with established diagnosis of CD in the same urban area and of the same age, the overall incidence increases to 2.6/1000. This prevalence, therefore, is higher, than that of 0.5/1000 previously reported in the general population, with a ratio of 1/4 between patients already known and the cases detected in this study.