Daniela Santon

Mass screening for coeliac disease using antihuman transglutaminase antibody assay

Aims: To determine coeliac disease prevalence by an anti-transglutaminase antibody assay in a large paediatric population; to evaluate acceptance of the screening programme, dietary compliance, and long term health effects. Methods: Cross-sectional survey of 3188 schoolchildren (aged 6–12) and prospective follow up of diagnosed cases. Main outcome measures were: prevalence of coeliac disease defined by intestinal biopsy or positivity to both human tissue transglutaminase and anti-endomysium antibodies in HLA DQ2-8 positive subjects; percentage of children whose families accepted screening; dietary compliance as defined by negativity for anti-transglutaminase antibodies; and presence of clinical or laboratory abnormalities at 24 month follow up. Results: The families of 3188/3665 children gave their consent (87%). Thirty biopsy proven coeliacs were identified (prevalence 1:106). Three other children testing positive for both coeliac related autoantibodies and HLA DQ2-8 but refusing biopsy were considered as having coeliac disease (prevalence 1:96). Of 33 cases, 12 had coeliac related symptoms. The 30 biopsy proven coeliacs followed a gluten-free diet. Of 28 subjects completing 18–24 months follow up, 20 (71.4%) were negative for anti-transglutaminase antibodies, while eight were slightly positive; symptoms resolved in all 12 symptomatic children. Conclusions: Prevalence of coeliac disease is high in Italian schoolchildren. Two thirds of cases were asymptomatic. Acceptance of the programme was good, as was dietary compliance. Given the high prevalence and possible complications of untreated coeliac disease, the availability of a valid screening method, and evidence of willingness to comply with dietary treatment population mass screening deserves careful consideration.

A reliable screening procedure for coeliac disease in clinical practice.

Background: The main autoantigen recognized by the sera of patients with coeliac disease (CD) is tissue transglutaminase (tTG). A human-recombinant form of tTG was used to develop an ELISA to measure anti-tTG serum antibodies for the diagnosis of CD. Preliminary retrospective reports suggest that the human tTG-based ELISA could identify coeliac patients missed by the IgA-anti-endomysium antibody test (AEA). Whether the human recombinant tTG ELISA is sufficiently accurate to become the main diagnostic CD tool in everyday clinical practice is unknown. The objective was to determine, in a prospective study, the sensitivity and specificity of an ELISA test based on the use of human tTG compared with AEA, to analyse the discordant cases for HLA DQ2-8 and for clinical and intestinal biopsy characteristics. Methods: 1106 patients referred to a gastrointestinal outpatient clinic for symptoms attributable to CD, 52 first-degree relatives of CD patients and 200 healthy controls were tested for both anti-human tTG and AEA antibodies. Results: Out of 1158 subjects, 146 were tested positive for anti-tTG antibodies and 140 were biopsy-proven coeliacs. The AEA test identified 126/1158 coeliacs who also tested positive for anti-tTG antibodies. The 14 patients missed by the AEA test carried the typical HLA-DQ for CD; they had normal levels of total serum IgA and had milder pathology than those with both anti-tTG and AEA positivity ( P < 0001). Conclusions: These results prove that human tTG-based ELISA is an excellent diagnostic tool for CD, for mass screening by both the specialist and the general clinic.

Evolution of the beta defensin 2 gene in primates

With the aim of further investigating the molecular evolution of beta defensin genes, after having analysed beta defensin 1 (DEFB1) in humans and several nonhuman primate species, we have studied the evolution of the beta defensin 2 gene (DEFB2), which codifies for a peptide with antimicrobial and chemoattractant activity, in humans and 16 primate species. We have found evidence of positive selection during the evolution of orthologous DEFB2 genes at two points on a phylogenetic tree relating these primates: during the divergence of the platyrrhines from the catarrhines and during the divergence of the Cercopithecidae from the Hylobatidae, Great Apes and humans. Furthermore, amino acid variations in Old World Monkeys seem to centre either on residues that are involved in oligomerisation in the human molecule, or that are conserved (40–80%) in beta-defensins in general. It is thus likely that these variations affect the biological function of the molecules and suggest that their synthesis and functional analysis might reveal interesting new information as to their role in innate immunity.

Epidemiological and molecular assessment of a rubella outbreak in North‐Eastern Italy

From January to June 2008, a rubella outbreak involving 111 laboratory confirmed cases occurred in the Friuli Venezia Giulia (FVG) region of North‐Eastern Italy. The outbreak occurred initially in two residential homes for young adults disabled mentally and physically. Subsequently, the epidemic spread to the general population. Young adult cohorts were mostly affected and the mean age of the patients was 26.8 years; the majority of cases were male (73.8%), with a mean age of 26.6 years in males and 27.4 in females. Three pregnant women had a primary infection and two had their pregnancies terminated. Genotyping of 16 isolates showed the circulation of RUBV 2B, a genotype originating from Asia and South Africa and now present in Europe. In addition, molecular analysis revealed a well defined space‐temporal spread of two viruses showing distinct sequences. A seroepidemiological survey carried out in a city within the same geographical area showed that the proportion of women of childbearing age still susceptible to rubella virus was 5.5%, fairly close to the figure (<5%) expected by 2010. J. Med. Virol. 82:1976–1982, 2010.

Persistent viremia and urine shedding of tick-borne encephalitis virus in an infected immunosuppressed patient from a new epidemic cluster in North-Eastern Italy.

A persistent tick-borne encephalitis virus infection in an immune-suppressed patient is presented. Such an unusual clinical case offers the unique chance of detecting persistent viremia associated to the erythrocyte fraction and shedding of the virus in the urine for more than six weeks. The infection occurred in a new area of the Friuli Venezia-Giulia region (North Eastern Italy) where two additional cases are also being reported.

Absence of maternal microchimerism in very early onset inflammatory bowel disease R1.

Kamio et al . have reported three local cases of A. xylosoxidans infection in the liver. 3 Computed tomography image of their case showed liver abscess. However, it also represents a liver mass simulating malignant tumor, as in the present case. The lesion exhibited a coralloid appearance and microscopically showed confluent epithelioid granulomas with necrosis and abscesses, but A. xylosoxidans itself is invisible on tissue specimens. The diagnosis can be made only by culture. Interestingly, all three reported cases and the present case had a history of cholecystectomy for cholecystolithiasis; the period between surgical intervention and the first symptom ranged from 5 to 38 months. This suggests that the cholecystectomy is the inciting event for pathogenesis. The source of the infection is unknown. Because A. xylosoxidans has been isolated from the gastrointestinal tract, this could be the source of the infection. 2,4