Epidemiological profile of hemoglobinopathies in the Mauritanian population

Psychiatric disorders and caregiver burden in children with transfusion dependent β-thalassaemia and their caregivers

BACKGROUND

Children with thalassemia need care from the first years of life owing to the physical and psychological effects of their disorder. Thalassemia is a concern not only for the children’s physical health but also the mental health of themselves and their caregivers.

AIM

To screen the psychosocial problems and assessment of psychiatric morbidities among thalassaemic children and their caretakers, along with an assessment of caregiver burden in them.

METHODS

In this observational cross-sectional study, children with transfusion-dependent thalassemia, were included and were assessed for psychiatric morbidity and global functioning. Their parents were assessed for psychiatric morbidity and the caregiver burden they faced. All the parents completed two different questionnaires to assess their knowledge about the psycho-social functioning [using Pediatric Symptom Checklist-35 (PSC-35)] of their children and the level of the burden faced by them by Caregiver Burden Scale (CBS).

RESULTS

A total of 46 children (28 boys and 18 girls) with transfusion-dependent thalassemia with a mean age of 8.83 ± 2.70 years and 46 parents (12 fathers and 34 mothers) were included in this study. More than 32 children had some psychosocial problems on screening by PSC-35. On assessment by CBS moderate caregiver burden was perceived in domains of general strain, isolation, disappointment, emotional involvement, and environment. A total of 65.3% of children and 62.7% of parents were diagnosed with psychiatric problems.

CONCLUSION

Thalassemia affects not only the persons with the disorder but also their caregivers in several aspects, including their psychosocial well-being. This study emphasizes the role of a supportive group in the psychological well-being of caregivers, which could be used to prevent the pathological effects of caregiver burden and enhance their psychological well-being through counselling.

Umbilical Cord Blood Screening for the Detection of Common Deletional Mutations of α-Thalassemia in Bangladesh

α-Thalassemia (α-thal) is assumed to be very prevalent in Bangladesh. We aimed to assess the prevalence of the disease in the country and provide a model for α-thal newborn screening in Bangladesh. We collected umbilical cord blood (UCB) samples from 413 unrelated newborns in Bangladesh. Demographic information, blood indices, osmotic fragility, serum iron (Fe), and zinc (Zn) levels were evaluated for all the subjects. All subjects underwent a polymerase chain reaction (PCR)-based diagnosis for α-thal status, followed by a multiplex gap-PCR-based identification of the deletion type present. Sixty-seven subjects had at least one α-thal deletion (16.22%). We observed that -α^3.7 (rightward), - -^SEA (Southeast Asian), -α^4.2 (leftward), - -^MED (Mediterranean) and - -^THAI (Thailand) deletions were the most common α-globin deletions present in the country, with the -α^3.7 (n = 37) and - -^SEA (n = 18) being most prevalent. The osmotic fragility test (OFT) could predict the presence of α-thal deletions with over 98.0% sensitivity. Complete UCB count analysis revealed significant differences between healthy subjects and subjects with α-thal deletions. Although the iron level was almost the same (108.0 vs. 105.7 µg/dL), a reduced level of Zn (98.6 vs. 71.8 µg/dL, p < 0.01) was observed in the cord blood-derived serum of the subjects with α-thal deletions. Moreover, parental age at the time of delivery, gestational period, and birth weight was lower in the subjects with α-thal deletions. This study provides partial information on the epidemiology of α-thal in Bangladesh and describes a model for α-thal newborn screening in the country.

Consanguinity and Inbreeding in Health and Disease in North African Populations

North Africa is defined as the geographical region separated from the rest of the continent by the Sahara and from Europe by the Mediterranean Sea. The main demographic features of North African populations are their familial structure and high rates of familial and geographic endogamy, which have a proven impact on health, particularly the occurrence of genetic diseases, with a greater effect on the frequency and spectrum of the rarest forms of autosomal recessive genetic diseases. More than 500 different genetic diseases have been reported in this region, most of which are autosomal recessive. During the last few decades, there has been great interest in the molecular investigation of large consanguineous North African families. The development of local capacities has brought a substantial improvement in the molecular characterization of these diseases, but the genetic bases of half of them remain unknown. Diseases of known molecular etiology are characterized by their genetic and mutational heterogeneity, although some founder mutations are encountered relatively frequently. Some founder mutations are specific to a single country or a specific ethnic or geographic group, and others are shared by all North African countries or worldwide. The impact of consanguinity on common multifactorial diseases is less evident.

Hb Moscva [β24(B6)Gly→Asp (GGT>GAT), HBB: c.74G>A]: An Unstable Hemoglobin Newly Detected as a De Novo Mutation in a Mauritanian Patient

Unstable hemoglobins (Hbs) are a group of Hb disorders that could be the origin of chronic hemolytic anemia. Most of these disorders are caused by point mutations taking place in the globin genes and affecting the stability of the Hb molecule. They are inherited as autosomal dominant diseases and described worldwide. Herein we report a new observation of an unstable variant in the Mauritanian population. The patient was a young girl of Mauritanian origin. She presented with chronic hemolytic anemia with an unknown etiology after being referred to several medical centers. Laboratory investigations based on routine analyses, capillary electrophoresis (CE), cation exchange high performance liquid chromatography (HPLC) and DNA sequencing revealed an abnormal unstable Hb known as Hb Moscva [β24(B6)Gly→Asp (GGT>GAT), HBB: c.74G>A] that occurred as a de novo mutation newly detected in an African girl of Mauritanian origin.

Clinicoinvestigational and demographic profile of children with thalassemia major

There are an estimated 200 million carriers of the β-thalassemia gene worldwide, 20 million being in India. The mean prevalence in India is 3.3 %. Objective To evaluate the clinico-investigational profile and the demographic characteristics of patients with thalassemia major (TM). Methods This was a retrospective analysis of the clinico-demographic profile at presentation of patients of TM diagnosed in the Paediatric Hematology Clinic of our hospital. Results The clinical profile of 964 patients of TM was analyzed. The mean age at presentation of untransfused children was 13.2 ± 9.7 months. Nearly 2/3(rd) children presented before 1 year of age. Almost 40 % had symptoms for 3 months prior to presentation. The manifestations at presentation included pallor and failure to thrive. About 40 % presented with severe anemia, with a hemoglobin of <5.0 gm/dl. A large number received blood transfusions prior to establishment of the diagnosis. Half of the families had ancestors who hailed originally from Pakistan. Approximately 50 % belonged to the Khatri/Arora castes. The parental literacy rate was about 90 %. Conclusions Thalassemia needs greater public awareness and prevention strategies in our country. Some communities are at high risk as compared to others. Education programs and compulsory antenatal screening appear to be the order of the day.

Epidemiological profile of common haemoglobinopathies in Arab countries

Haemoglobinopathies including the thalassemias and sickle cell disease are known to be prevalent inherited disorders in most Arab countries with varying prevalence rates and molecular characterisation. β-thalassemia is encountered in polymorphic frequencies in almost all Arab countries with carrier rates of 1-11 % and a varying number of mutations. The most widespread mutation in Lebanon, Egypt, Syria, Jordan, Tunisia and Algeria is the IVS-I-110 (G>A). In the Eastern Arabian Peninsula, the Asian Indian mutations (IVS-I-5 (G>C), codons 8/9 (+G) and IVS-I (-25 bp del)) are more common. The α-thalassemias are encountered in the majority of Arab countries in frequencies ranging from 1 to 58 % with the highest frequencies reported from Gulf countries. The (-α(3.7)) mutation is the most frequent followed by the non-deletional α2 polyadenylation signal mutation (AATAAA>AATAAG) and the α2 IVS1 5-bp deletion. The rates of sickle cell trait in Arab countries range from 0.3 to 30 %, with the Benin, the Arab-Indian and the Bantu haplotypes constituting the bulk of the haplotypes, leading to two major phenotypes; a mild one associated with the Arab-Indian and a severe one with the Benin and Bantu haplotypes. Public health approaches targeting prevention of haemoglobinopathies in Arab countries include newborn screening for sickle cell disease, and premarital screening for carriers of β-thalassemia and sickle cell disease. These services are still patchy and inadequate in many Arab countries recommending the upgrade of these services with strengthening of the education and training of health care providers and raising public awareness on the feasibility of prevention and care for haemoglobinopathies.

Evolution of hemoglobinopathy prevention in Africa: results, problems and prospect

Hemoglobinopathies are a group of inherited hemoglobin disorders. Initially described in the subtropical regions, they are now spread all around the world because of migration. Their high frequency and clinical severity make them a major public health problem mostly in Africa due to the limited resources reserved for the management and prevention of these diseases. Despite considerable advances in the control and management of the hemoglobinopathies, therapeutic approach and follow- up still pose problems because of the major economic and organizational difficulties in the developing countries, particularly in Africa where problems are majored by other factors including social and cultural backgrounds, high consanguinity, as well as the coexistence of infection and malnutrition. Effective prevention programs have been carried out successfully in many European countries concerned by hemoglobinopathies. They should be extended to African regions where hemoglobin disorders account for more than 70% of total hemoglobinopathies in the world. Prevention should remain the major priority of health services to reduce incidence of hemoglobinopathies in Africa. Hereby we present the Tunisian experience that may reflect globally the profile of the prevention evolution of hemoglobinopathies in North Africa.

Enfermedad de células falciformes: registro de la Sociedad Española de Hematología Pediátrica

INTRODUCTION

Sickle cell disease (SCD), a genetic anemia, is currently an emerging health problem in Spain. Since 2000, The Spanish Society of Pediatric Hematology has maintained a registry of these patients. The data corresponding to 2004 are presented herein.

PATIENTS AND METHODS

Information was sent by different national hospitals. Pediatric patients with SCD followed-up during 2003 were registered in the first quarter of 2004. Data on epidemiology, diagnosis, treatment and outcome in each patient were gathered.

RESULTS

A total of 138 patients in 24 national hospitals were registered. Of these, 99 were still under follow-up. There was no significant difference in sex. The mean age was 8.2 years. Seventy-eight percent of the patients were homozygous. Forty-four percent were born in Africa but 76% had abnormal genes originating in Africa. Neurophysiologic disorders were detected in 36% of the patients. Symptomatic treatment was given in 65%, hydroxyurea in 27%, hypertransfusional therapy in 3%, and chelation therapy, indicated for ferric overload, was provided in 4%. None of the patients underwent stem cell transplantation. Acute complications requiring hospitalization occurred in 21%, and chronic complications were observed in 27%. The most frequent chronic complications were delayed height and weight gain and liver and biliary tract disorders. Two patients died.

CONCLUSIONS

This study confirms a highly significant increase in the prevalence of pediatric patients with SCD in the last 4 years, requiring greater resources to be devoted to the diagnosis and follow-up of this disease.

Haemoglobin variants and anaemia among pre-school/school children in north-east Brazil

In this study we investigated the presence of haemoglobin (Hb) variants and anaemia among 382 pre-school/school children from Bahia State, Brazil, a state where intermixing involving people from African origin is the highest in the country. Hb variants were investigated by cellulose acetate electrophoresis at alkaline pH. The pattern obtained was confirmed by citrate agar electrophoresis at pH 6.2. From the 382 children investigated, 79 (20.7%) had Hb variants: 47 (59.5%) had HbAS, 28 (35.4%) HbAC, 3 (3.8%) HbSC and 1 (1.3%) HbCC. Two hundred and fourteen children had anaemia. From these, 39 had microcytosis and 14 had low values of ferritin (<12 ng/ml). We cannot exclude thalassaemia among the children with microcytosis and hypochromia because it was not investigated. The majority of the children showed high mean values of ferritin, suggestive of subclinical infection. There was no difference when we compared the prevalence of anaemia among children with Hb variants (65.8%) and those without Hb variants (53.5%) (P = 0.06). These data demonstrate that Hb variants and anaemia are probably important public health problems in north-east Brazil.