Duodenal intraepithelial lymphocytosis during Helicobacter pylori infection is reduced by antibiotic treatment.

AIM: To evaluate clinical, biological and immunological features of patients with increased duodenal intraepithelial lymphocytes (IELs), and its relation to Helicobacter pylori (HP) and coeliac disease (CD). METHODS: We have studied all patients accrued over a 4-year period with increased duodenal IELs. Those patients were recalled for biological and immunological evaluation and a second endoscopy. RESULTS: Twenty-three from a total of 639 patients were identified and 17 of them were included in the study. The median duodenal IEL count was 59 per 100 epithelial cells. Twelve (71%) patients were HP+; eight of them received HP eradication. At the second endoscopy the duodenal IEL count was significantly lower 2 months after HP eradication (73 versus 28), while the IEL count was unchanged in those patients seronegative for HP (n = 5) or those in whom it was not eradicated (n = 4) (55 versus 55). No patient had coeliac antibodies, four expressed HLA-DQ2, lower than in the general population, and the prevalence of CD was 2% (12/639 patients). CONCLUSION: In some cases an increased duodenal IEL count may be due to an inappropriate host response to HP. HP screening and eradication should be considered before recommending a gluten-free diet.

[Good practices for the study of hemoglobin]. / Bonnes pratiques de l'étude de l'hémoglobine.

Hemoglobinopathies have become a significant national health problem in France. The biologists have a pivotal role in the genetic diagnoses. Although sickle cell disease (SCD) is the most frequent abnormality found: not less than 200 new cases are observed each year at birth, many other globin gene variations are found in the various ethnic groups. Since 1995 a neonatal sickle cell screening program has been established for at risk newborns. This programme is supported by the "Association française de dépistage et prévention des handicaps de l'enfant" (AFDPHE). The characterization of hemoglobin genetic variations requires a comprehensive set of laboratory techniques for which we specify here main clinical and technical recommendations.

[Auto-antibodies against acetylcholine receptors in myasthenia gravis]. / Auto-anticorps anti-récepteur de l'acétylcholine au cours de la myasthénie.

USEFULLNESS OF DETECTION OF ANTIBODIES AGAINST THE ACETYLCHOLINE RECEPTOR IN THE DIAGNOSIS OF MYASTHENIA GRAVIS (MG): MG is an autoimmune disorder including a fatigability of skeletal muscles and the presence of antibodies against the acetylcholine receptor (AChRAbs). These Abs are pathogenic by blocking the acetylcholine receptor within the neuromuscular junction. A transient neonatal MG occurs in 12% of babies born to myasthenic mothers. AChRAbs have been found in 77 to 89% of systemic MG and in 47 to 60% in ocular form of MG. These Abs are generally directed against the "Main Immunogenic Region" (MIR) within the a subunit of the receptor; others are directed against beta, gamma and epsilon subunits. Eleven to 23% of the MG are negative for the Abs directed against the a subunit reinforcing the interest to detect the other AChRAbs, specially the anti-epsilon subunit Abs and the Abs directed against the muscle-specific receptor tyrosine kinase. MULTICENTER EVALUATION: In order to compare the results of AChRAbs for a same patient from various laboratories, a multicenter study was performed on 26 sera with different titers of AChRAbs using radioimmunoassays. Six french laboratories have participated to this study. The antigen was obtained from TE671 cells for 5 laboratories (3 used a commercial test) or from human muscle (1 laboratory). At the end of the study, the qualitative analysis of the results showed a concordance of 92.3%. The interpretation of AChRAbs assays can thus be done by clinicians whatever the test is used. A same quality control is nowadays used by the six laboratories in order to estimate quantitative results according to the assay performed. USEFULNESS OF THE OTHER ABS: The Abs directed against the striated muscle are good markers of thymoma in MG but are not specific for MG. The Abs directed against titin which is the major target of the anti-striated muscle Abs, are also good biological markers of thymoma specially in MG adults younger than 60 years. The detection of anti-myoid cells and thymic reticuloepithelial cells Abs is no more useful due to a lower sensitivity compared to the Abs directed against the striated muscle.