Variability of anti-human transglutaminase testing in celiac disease across Mediterranean countries.

AIM: To verify the precision and accuracy of transglutaminase antibodies (TGA) assays across Mediterranean countries. METHODS: This study involved 8 referral centres for celiac disease (CD) in 7 Mediterranean countries. A central laboratory prepared 8 kits of 7 blinded and randomized serum samples, with a titrated amount of Human TGA IgA. Each sample was analysed three times on three different days, with each centre running a total of 21 tests. The results were included in a blindly coded report form, which was sent to the coordinator centre. The coordinator estimated the mean coefficient of Variation (CoVar = σ/µ), the mean accuracy (Accur = Vobserved - Vreal) and the mean percent variation (Var% = [(Vobserved - Vreal)/Vreal] × 100). RESULTS: The analysis showed that 79.17% of the mean variation fell between -25% and +25% of the expected value, with the accuracy and precision progressively increasing with higher titres of TGA. From values 1.25 times greater than the normal cut-off, the measurements were highly reliable. CONCLUSION: TGA estimation is a crucial step for the diagnosis of CD; given its accuracy and precision, clinicians could be confident in establishing a diagnosis.

Diagnosis of celiac disease and applicability of ESPGHAN guidelines in Mediterranean countries: a real life prospective study.

BACKGROUND: We assessed how the diagnosis of Celiac Disease (CD) is made and how the new ESPGHAN guidelines can be applied in children from countries with different resources. METHODS: A real life prospective study was performed in 14 centres of 13 different Mediterranean countries. Participants were asked to apply the usual diagnostic work-up for CD according to their diagnostic facilities. RESULTS: There were 1974 patients enrolled in the study, mean age 4 years, 10 months; 865 male, 1109 female. CD was confirmed in 511 (25.9%) and was unconfirmed in 1391 (70.5%) patients; 14 patients were diagnosed as having CD according to the new ESPGHAN guidelines, 43 patients were classified as having potential CD. In all participating countries the diagnosis of CD relied on histology of duodenal biopsy; in 5 countries, HLA, and in one country endomysial antibodies (EMA) were not available. Symptoms did not add a significant increase to the pre-test probability of serological tests. The positive predictive value of tissue transglutaminase type 2 (tTG) antibodies performed with different kits but all corresponding to those recommended by ESPGHAN was 96.1% (95% CI 94-97.9%) in presence of tTG > 10xULN. In 135 patients with tTG >10xULN, HLA genotyping was performed and in all it was compatible with CD. CONCLUSIONS: The results of our study show that CD diagnosis still relies on intestinal biopsy in the Mediterranean area. New ESPGHAN criteria are not applicable in 5 countries due to lack of resources needed to perform HLA genotyping and, in one country, EMA assay. Further simplification of the new ESPGHAN guidelines might be made according to what preliminarily the present results suggest if confirmed by new prospective studies.

A point-of-care test for facing the burden of undiagnosed celiac disease in the Mediterranean area: a pragmatic design study.

BACKGROUND: We aimed at assessing the factors that can influence results of the dissemination of an already validated, new generation commercial Point-of-Care Test (POCT) for detecting celiac disease (CD), in the Mediterranean area, when used in settings where it was designed to be administered, especially in countries with poor resources. METHODS: Pragmatic study design. Family pediatricians at their offices in Italy, nurses and pediatricians in Slovenia and Turkey at pediatricians', schools and university primary care centers looked for CD in 3,559 (1-14 yrs), 1,480 (14-23 yrs) and 771 (1-18 yrs) asymptomatic subjects, respectively. A new generation POCT detecting IgA-tissue antitransglutaminase antibodies and IgA deficiency in a finger-tip blood drop was used. Subjects who tested positive and those suspected of having CD were referred to a Celiac Centre to undergo further investigations in order to confirm CD diagnosis. POCT Positive Predictive Value (PPV) at tertiary care (with Negative Predictive Value) and in primary care settings, and POCT and CD rates per thousand in primary care were estimated. RESULTS: At tertiary care setting, PPV of the POCT and 95% CI were 89.5 (81.3-94.3) and 90 (56-98.5) with Negative Predictive Value 98.5 (94.2-99.6) and 98.7% (92-99.8) in children and adults, respectively. In primary care settings of different countries where POCT was performed by a different number of personnel, PPV ranged from 16 to 33% and the CD and POCT rates per thousand ranged from 4.77 to 1.3 and from 31.18 to 2.59, respectively. CONCLUSIONS: Interpretation of POCT results by different personnel may influence the performance of POC but dissemination of POCT is an urgent priority to be implemented among people of countries with limited resources, such as rural populations and school children.

Celiac disease in the Mediterranean area.

BACKGROUND: The World Gastroenterology Organization recommends developing national guidelines for the diagnosis of Celiac Disease (CD): hence a profile of the diagnosis of CD in each country is required. We aim to describe a cross-sectional picture of the clinical features and diagnostic facilities in 16 countries of the Mediterranean basin. Since a new ESPGHAN diagnostic protocol was recently published, our secondary aim is to estimate how many cases in the same area could be identified without a small intestinal biopsy. METHODS: By a stratified cross-sectional retrospective study design, we examined clinical, histological and laboratory data from 749 consecutive unselected CD children diagnosed by national referral centers. RESULTS: The vast majority of cases were diagnosed before the age of 10 (median: 5 years), affected by diarrhea, weight loss and food refusal, as expected. Only 59 cases (7.8%) did not suffer of major complaints. Tissue transglutaminase (tTG) assay was available, but one-third of centers reported financial constraints in the regular purchase of the assay kits. 252 cases (33.6%) showed tTG values over 10 times the local normal limit. Endomysial antibodies and HLA typing were routinely available in only half of the centers. CD was mainly diagnosed from small intestinal biopsy, available in all centers. Based on these data, only 154/749 cases (20.5%) would have qualified for a diagnosis of CD without a small intestinal biopsy, according to the new ESPGHAN protocol. CONCLUSIONS: This cross-sectional study of CD in the Mediterranean referral centers offers a puzzling picture of the capacities to deal with the emerging epidemic of CD in the area, giving a substantive support to the World Gastroenterology Organization guidelines.

Is the rapid whole blood test useful for diagnosis and monitoring celiac disease in children?

AIM: To evaluate a new whole blood rapid test for the detection of IgA anti-transglutaminase (ATG) for diagnosis and diet survey of celiac disease (CD). METHODS: 57 children, 20 of them were CD patients on a gluten-free diet and 37 were under suspicion of CD were enrolled. IgAATG was detected by the conventional ELISA test and the new rapid whole blood test. RESULTS: Concordance between the 2 tests was 96.4%. All patients positive with ELISA were also positive by the rapid test. Only 2 patients were slightly positive by the rapid test and negative by ELISA. CONCLUSION: Whole blood rapid test seems to be as performant as ELISA test for IgAATG detection.

HLA class II polymorphism in children with coeliac disease in Tunisia: is there any influence on clinical manifestation?

OBJECTIVE: To elucidate the HLA DRB1, DQB1 and DQA1 polymorphism in Tunisian children with typical form of coeliac disease (CD) in comparison with those from mass screening (atypical and silent CD). MATERIALS AND METHODS: We recruited three groups: group I: 40 CD children diagnosed according to the ESPGHAN criteria. group II: 40 healthy controls matched with sex, age and geographic origin. group III: 38 CD children coming from mass screening in schoolchildren. HLA class II DRB1, DQB1 and DQA1 alleles were typed by PCR-sequence-specific primer. RESULTS: Comparing the groups I and II, we found a pronounced increase of the susceptible alleles HLA DRB1*03 (relative risk, RR = 4.18, Pc = 0.001), DQB1*02 (RR = 7.9, Pc<0.0001) and DQA1*0501 (RR = 4.1, Pc = 0.001). As for protective alleles, we detected a high frequency of DRB1*13 (RR = 0.059, Pc = 0.001), DQA1*0102 (RR = 0.071, Pc = 0.009) and DQB1*06 (RR = 0.125, Pc = 0.0042). Haplotype analysis showed that the main combination observed was the conformation of DQ2 (DQA1*0501-DQB1*02) in 36 patients from group I and 30 from group III. There was no statistically significant difference between the groups I and III according to the distribution of the different alleles. CONCLUSION: We confirmed in this study the high frequency of DQ2 haplotype in CD patients and we identified new protective alleles DRB1*13, DQA1*0102 and DQB1*06. However, HLA polymorphism seems to have no evident impact on clinical outcome of CD.

Prevalence of celiac disease in Tunisia: mass-screening study in schoolchildren.

BACKGROUND: Celiac disease is reported to be common among North Africans, particularly Tunisians. Nevertheless, the prevalence of coeliac disease in the general population has not been previously investigated. OBJECTIVE: This study aimed to determine the prevalence of celiac disease among children in Tunisia and to describe the clinical profile of the screened patients. METHODS: A mass screening study based on drawing lots was carried out on schoolchildren in Ariana, a Tunisian district. A participation agreement was obtained from 6286 children (3175 boys, age: 9.7+/-3 years). Two children of known celiac disease were present in this population. All participants were tested for IgA antitissue transglutaminase antibodies (IgA-tTG) by a commercial enzyme-linked immunosorbent assay (ELISA) and total IgA levels. Sera, found positive by the initial screening, were assessed by immunofluorescence for the presence of IgA antiendomysium antibodies (IgA-AE). Positive participants were also called in for serological control, intestinal biopsy, biological exploration (hemoglobin rate, calcemia and albuminemia) and bone mineral densitometry. RESULTS: Among the 6284 participants, 139 (1/45) were positive for IgA-tTG. Forty-two of these had low-level IgA-tTG and no one had IgA deficiency. IgA-AE was detected in 40 participants. One hundred and seven children were called in, 28 had both positive tests (IgA-tTG +/IgA-AE+) and 79 were only positive for IgA-tTG (IgA-tTG +/IgA-AE-). Intestinal biopsy was performed in the 28 participants of the first group (IgA-tTG +/IgA-AE+) and confirmed celiac disease in 26 cases. In the second group (IgA-tTG +/IgA-AE-), intestinal biopsy was performed in 26 children and histological examination was normal in all cases. Among the 26 biopsy-proven celiac disease children, six (23%) had typical clinical symptoms of celiac disease, whereas the others had atypical forms with 11 (42%) asymptomatic. In 23 biopsy-proven celiac disease children, bone mineral density was significantly lower than that of a group of 109 normal children (0.850+/-0.06 g/cm2 versus 0.912+/-0.06 g/cm2, P<0.05). Seven participants (30.4%) among the celiac disease children and six (7.5%) among the controls had a total-body Z score for bone mineral density of <-2 (P<0.001). CONCLUSION: The prevalence of celiac disease in Tunisian schoolchildren, estimated to be about 1/157, is close to the European prevalence. Most of the screened children showed an atypical and asymptomatic form, but even the typical forms were underdiagnosed. Ostopenia was frequently observed in celiac disease patients.

[A novel mutation in infant hypophophatasia: a case report]. / Une nouvelle mutation de l'hypophosphatasie de l'enfant: a propos d'un cas Tunisien.

BACKGROUND: Hypophosphatasia is a rare inherited disorder characterized by defective bone and teeth mineralization and deficiency of serum and bone alkaline phosphatase activity. Several mutations in the TNSALP gene are identified. AIM: The authors describe a Tunisian case having a mutation that has not been described up to now. CASE: It is about an infant, in the antecedents of recurring disease of the lungs in child since the age of seven months, which presents clinical and radiological signs of rickets. The diagnosis of hypophosphatasia is strongly suspected in front of Reduced serum alkaline phosphatase activity and confirmed by the genetic study. The child is homozygous for a new mutation L282P in the ninth exon of the gene. The parents and two brother and sister are heterozygous for the same mutation.

[Deficient expression of leukocyte adhesion proteins. A new Tunisian case]. / Le défaut d'expression des protéines d'adhésion leucocytaire. A propos d'une nouvelle observation Tunisienne.

Leukocyte adhesion deficiency (LAD) is a rare primary immunodeficiency inherited as an autosomal recessive genetic disorder. LAD was suspected in a four days old girl. She was born from healthy first cousins. A family history of a boy who died from omphalitis and sepsis was reported. Our patient had the severe form, she had delayed umbilical cord separation and suffered recurrent infections. She had a deletion of the G at position 1497. The patient received bone marrow transplantation from her HLA-identical mother at age of 14 months. She is now 9 years old and in good health.

[Pulmonary alveolar proteinosis in two siblings. A case report]. / La protéinose alvéolaire pulmonaire de l'enfant. A propos d'une observation familiale.

Pulmonary alveolar proteinosis (PAP) is a rare disorder in children. This report describes two siblings in whom PAP developed during infancy (three years for the boy and four years two months for the girl). The girl was admitted for chronic respiratory distress. Chest x-ray showed a reticulonodular pattern. Her brother was asymptomatic. The diagnosis of PAP was confirmed by open lung biopsy for the boy and broncho-alveolar lavage for the girl. Therapeutic broncho-alveolar lavages were performed (six for the girl and two for the boy), the girl lost dependence on oxygen therapy. 6 years later, the brother is still asymptomatic. The sister had two episodes of respiratory distress, after two and four years, that required therapeutic lavages. The last therapeutic bronch-oalveolar lavage was performed for the first time by a Tunisian team.

[Acute leukoencephalitis in infant treated by high-dose corticosteroid. A case report]. / Leucoencephalite aigue du nourrisson traitee par fortes doses de corticoides.

The authors report a case of acute post infectious leukoencephalitis observed in a tow-years and a half children admitted to our hospital for fiver with suddent condition deterioration, obnibulation, coma and paralysis of the 6th and 7th cranial nerve. Cerebrospinal fluid study showed lymphocytosis with negative culture. Head magnetic resonance imaging demonstrated diffuse high signals over the white matter on T2 weighted images so the diagnosis was confirmed. High dose corticosteroid therapy was effective.

Clinical and genetic heterogeneity in Desbuquois dysplasia.

Desbuquois dysplasia is a rare chondrodysplasia of autosomal recessive inheritance characterized by short stature, joint laxity, facial anomalies, a "Swedish key" appearance of the proximal femur, and advanced carpal and tarsal bone age. Patients with Desbuquois dysplasia can be divided in two groups, depending on whether hand changes include an extra ossification center distal to the second metacarpal and whether phalangeal dislocations are present or absent. We have recently reported linkage of a Desbuquois dysplasia gene to 17q25.3 in a group of patients with typical hand abnormalities. Here, we report on the exclusion of the 17q25.3 locus in three inbred Desbuquois families originated from Turkey, Asia, and Morocco without typical hand abnormalities. Microsatellite DNA markers from the 17q25.3 region were used at an average spacing of 2 cM, and the three affected individuals from families 1 to 3 were heterozygous for the 17q25.3 region. These results allow us to exclude this region as the locus in Desbuquois families with no hand anomalies and demonstrate genetic heterogeneity. Ongoing studies will hopefully lead to the identification of the responsible genes.