lower-cost protocol for sickle cell disease neonatal screening in Tunisia

Sickle cell disease [SCD] is a group of hereditary chronic anemias that manifest essentially a painful crisis and susceptibility to infection. Neonatal screening is a preventive action that reduces the rates of mortality due to complications arising from infections by encouraging early prophylactic penicillin use and pneumococcal vaccination. The purpose of this pilot study was to set up a neonatal screening protocol at a lower cost than one that uses commercially available screening kits. Pilot study conducted over 1 year in two Tunis maternity hospitals. Samples from 9148 newborns were collected using paper printed using a common office printer to collect blood spots from the newborns. A lab-prepared agarose gel for isoelectrofocusing [IEF] was used to test the dried blood samples from these newborns. The IEF on lab-prepared agarose gels was efficient since it was able to detect the main abnormal Hbs previously identified in the Tunisian population [HbS, HbC, HbO, and HbG]. Furthermore, when data collected in this screening program were compared with the previously established national data, no statistically significant differences were found. After analysis, results were given back to the families of the patients, and the major Hb cases were directed to one of the hemoglobinopathies specialized centers, where at-risk couples benefited from genetic counselling and were informed about the possibility of prenatal diagnosis. This pilot experiment demonstrated the feasibility of SCD neonatal detection using a lower cost method as well as detection of other main structural Hb variants

alpha-Thalassaemia in Tunisia: some epidemiological and molecular data.

Unlike the other haemoglobinopathies, few researches have been published concerning alpha-thalassaemia in Tunisia. The aim of the present work is to acquire further data concerning alpha-thalassaemia prevalence and molecular defects spectrum in Tunisia, by collecting and studying several kinds of samples carrying alpha-thalassaemia. The first survey conducted on 529 cord blood samples using cellulose acetate electrophoresis, have displayed the prevalence of 7.38% Hb Bart's carriers at birth. Molecular analyses were conducted by PCR and DNA sequencing on 20 families' cases from the above survey carrying the Hb Bart's at birth and on 10 Hb H diseased patients. The results showed six alpha-globin gene molecular defects and were responsible for alpha-thalassaemia: -alpha(3.7), - -(MedI), alpha(TSaudi), alpha(2)(cd23GAG->Stop), Hb Greone Hart: alpha(1)(119CCT->TCT) corresponding to 11 genotypes out of which two are responsible for Hb H disease (- -(Med)/-alpha(3.7)) and (alpha(TSaudi)alpha/alpha(TSaudi)alpha) and a newly described polymorphism: alpha+6C->G. The geographical repartition of alpha-thal carriers showed that the -alpha3.7 deletion is distributed all over the country, respectively the alpha(HphI) and alpha(TSaudi) seem to be more frequent in the central region of the northeast region. The haematological and clinical data showed a moderate phenotype with a late age of diagnosis for Hb H disease. This work had permitted, in addition to an overview on alpha-thalassaemia in the country, the optimization of protocols for alpha-thalassaemia detection in our lab, allowing further investigations concerning phenotype-genotype correlation in sickle cell disease or beta-thalassaemia.

Clinical characteristics and outcome of cystic fibrosis: report of 16 cases

The aim of this report is to determine clinical characteristics and outcome of Cystic Fibrosis [CF]. Cases of CF managed at Infantile Medecine A Department in Children's Hospital of Tunis during 13 years [1994 -2006] were reviewed. 16 children had CF. They were 8 males and 8 females. 13 patients were consanguineous and four had similar familial cases. The mean age at diagnosis was 19 months [10 days, 13 years]. 3/4 of patients were symptomatic within the first trimester of life. Revealing symptoms were: obstructive bronchopathy associated to chronic diarrhea [n = 6], oedema-anemia-hypotrophy-hypoprotidemia syndrome [n = 3], meconium ileus [n = 4], bronchiectasis [n = 2] and chronic diarrhea [n = l]. The diagnosis was confirmed by sweat test and genotypic data. The F508 del was the most frequent mutation [54%]. Clinical outcome was characterized by the occurrence of respiratory and nutritional complications: acute respiratory failure [n = 6], chronic respiratory failure [n = 3], chronic pseudomonas aeruginosa infection [n = 6] at a medium age of 3.8 years, recurrent haemoptysis [n = 2], pleural effusion [n = 2], a malnutrition [n = 10] and diabetes associated to puberty delay in one patient. Seven patients died at mean age of 4.4 years [6 months, 17.3 years]. Among surviving patients, six had no compromised nutritional status or lung function. Prenatal diagnosis was performed in three families. CF is characterized by earliest onset and severity of symptoms. Therapeutic insufficiency is the main cause of precocious complications and poor prognosis in our series

[Prenatal diagnosis of hemoglobinopathy: seria of 37 cases]

Objectives: to determine the main hemoglobinopathies in order to act for the reduction of the cases of homozygosis and this, by an early prenatal diagnosis

Methods: It is a retrospective study of 37 cases of antenatal diagnosis for hemoglobinopathies during a 5 years period and having detected 8 homozygous fetus

Results: The mean age of the patients was 32 years. 62 per cent of the patients were originating in the North-West of the country. 56.7 per cent of the patients had a marriage between blood relations. A family antecedent of hemoglobinopathy was noted in all of the cases. The age of the pregnancy at the time of the realization of the prenatal diagnosis was 15 weeks of amenorrhoea and 6 days. 75.7 percent of the patients had an amniocentesis and 24.3 per cent a chorionic villus sample. The detected homozygous fetus accounted for 12.6 per cent of the cases for which a medical interruption of pregnancy was practiced

Conclusion: Because of the frequency and gravity of the hemoglobinopathies in our country, of the recommendations to improve quality of tracking are in particular proposed the preferential recourse to the biopsy of the placental villi and, if necessary with the other methods of taking away when the request of the prenatal diagnosis is late

[Prevalence and causal factors of anemia in children in Tunisia]

Anemia continue to be prevalent among children under five years despite the improvement of socioeconomic and sanitary indicators. The purpose of the present cross-sectorial study is to assess the etiologic factors responsible for anemia. Knowledge of the relative importance of the different causes should form a basis for intervention strategies to prevent and control anemia. The survey covered 955 children under the age of five years, native of two regions with the highest prevalence of anemia, the Southwest and the District of Tunis. The results showed that 29% of children suffered from anemia. About 70% of them were iron deficient. The fractions of the deficiency in vitamin B 12 and in folates were insignificant Only 3% of children had chronic inflammation associated with [and possibly responsible for] their anemia A little fraction of anemia [=5%] was due to thalassemia or drepanocytosis. Picawasan important causal factor of iron deficiency anemia. The parasites identified in stool could not cause anemia

mucoviscidose chez l'enfant: Experience d'un service Tunisien de pediatrie generale

Cystic fibrosis was regarded a long time as exceptional in the Nord Africaine population and in particular in Tunisia what was at the origin of the ignorance of its various diagnostic and 'therapeutic aspects in our country. Nevertheless, with the development of the means of the diagnosis, several cases of cystic fibrosis were diagnossd these last years what will pose true problems of assumption of responsibility of these children like illustrates it well our experiment in the pediatric department of Sfax university hospital. In 10 years going of 1991 to 2000 we reported 7 cases of cystic fibrosis in the peditric department of Sfax university hospital. Our patients are 3 boys and 4 girls. The age of revelation of the disease varied from 3 months to 14 years with 4 years and 10 months an average age. All our patient had a respiratory symptomatology in the Foreground. The evolution was marked by the death of 4 patients at an average age of 5 years and half whereas the 3 surviving patients for the moment are more or less balanced on the nutritional level, digestive and respiratory. Cystic fibrosis is not exceptional in our area, its assumption of responsibility therapeutic is difficult, and it requires the collaboration of several experts and a good compliance of the child and of his family

Depistage des alpha thalassemies en Tunisie [a travers 1500 cas]

A systematic survey has been realized in a maternity of Tunis including 1500 new born [cord blood samples]. Hb Bart's amount has been evaluated and revealed 71 cases of alpha thalassemia including three groups: Silent alpha thalassemia, minor alpha thalassemia, hemoglobin H disease. In another part, correlation between Hb Bart's and hematological parameters has been studied

Les manipulations en geniegenetique incidences et domaines d'application

The genetic engineering permits to produce useful proteins. Authors describe some aspects of cloning strategies and the principal applications in medical, industrial and agricultural domains

Identification des hemoglobines abormales par isoelectrofocalisation

Using IEF on slabs of acrylamide gel was adapted [or screening of abnormal hemoglobins which are at the same level by electrophoresis on cellulose acetate strips. This method is fast, inexpensive and allowed the simultaneous analysis of 70 samples of woole blood. The characterization technique of IEF allowed us to distinguish some rare variants like Hb o Arab, HbD and Tgamma in B0- thalassemia