Detection of secretory IgA antibodies against gliadin and human tissue transglutaminase in stool to screen for coeliac disease in children: validation study

Objective To evaluate two commercial stool tests for detection of secretory IgA antibodies against gliadin and human tissue transglutaminase for diagnosis of coeliac disease in children with symptoms.Setting Tertiary care children's hospital.Participants Coded stool samples from 20 children with newly diagnosed coeliac disease and 64 controls. Six children with coeliac disease had stool tests every two weeks for three months after starting a gluten-free diet.Main outcome measures Secretory IgA antibodies against gliadin and human tissue transglutaminase in stool samples, determined in duplicate by using recommended cut-off limits.Results Sensitivity of faecal antibodies against human tissue transglutaminase was 10% (95% confidence interval 1% to 32%), and specificity was 98% (91% to 100%). For antibodies against gliadin, sensitivity was 6% (0% to 29%) and specificity was 97% (89% to 100%). Optimisation of cut-off limits by receiver operating characteristic analysis and use of results of both tests increased sensitivity to 82%, but specificity decreased to 58%. All follow-up stool tests remained negative, except for two positive anti-gliadin results in one patient, six and 10 weeks after the gluten-free diet was started.Conclusions Neither stool test was suitable for screening for coeliac disease in children with symptoms

Atypical CD3+ CD4(low) cell population in a boy with fatal EBV-infection

A previously healthy 10-year-old Greek boy born to nonconsanguineous healthy parents developed progressive liver disease after acute infectious mononucleosis. EBV-induced autoimmune hepatitis was suspected and treatment was started with high-dose prednisolone, acyclovir and intravenous immunoglobulins. Despite therapy his liver function continuously deteriorated and the child died 9 months later in profound immune deficiency from candida septicemia. Flow cytometric analysis of his lymphocytes revealed a major subpopulation of atypical cells (20.3%) which were CD3+, fitted into the lymphocyte gate bur showed a very low level of CD4 expression, comparable to that of monocytes. After short-time cell culture, the cells became adherent and developed granules and dendrites; We conclude that these cells may represent strongly activated CD4+ T lymphocytes with downregulated CD4 expression or a subtype of dendritic cells