Prevalence of the sickle cell gene in Yemen: a pilot study

Knowledge and attitude of Engaged and Recently Married Couples Toward Premarital Screening: A Cross-Sectional Study

Background and Objective: Despite that inherited (thalassemia and SCA) and infectious (hepatitis B, hepatitis C and AIDs) diseases and their risk factor consanguineous marriage are widespread among Yemen population, community-based awareness studies towards premarital screening (PMS) is extremely limited, so our study is designed to elicit knowledge and attitude of engaged and recently married couples in Taiz (Yemen) toward PMS. Methods: A cross-sectional study was conducted from April to September 2021 at Taiz. A well-structured questionnaire was designed and then delivered to participants to collect data. Results: The results revealed that majority of respondents (83.60%-94.18%) had knowledge about inherited and infectious diseases, respectively, and educational institution was the main knowledge source. Females had significantly higher knowledge than males (P ≤ .01), except about AIDs since no difference (P = .539). The results also revealed that majority of respondents had positive attitudes toward PMS, except toward AIDs testing since 70% of males and 68.91% of females had negative attitudes. The majority of respondents agreed that screening reduces the diseases incidence. Approximately half of respondents (50.79%-56.61%) tend to go ahead for marriage in case of positive results for inherited and infectious diseases respectively. Making PMS as an obligatory step prior engagement was agreed by 47.62% of respondents (45.71% of males, 48.74% of females). Conclusion: A high level of knowledge and positive attitudes toward inherited and infectious diseases and PMS were reported. This knowledge reflected on the agreement of majority of respondents regarding PMS importance in term of reduction of diseases incidence.

Prevalence of Sickle Cell Trait in the Southern Suburb of Beirut, Lebanon

Objective

The objective of this study was to assess the prevalence, gender differences, and time trends of Sickle Cell Trait in the Southern Suburb of Beirut, Lebanon, as well as to highlight the importance of screening for Sickle Cell Trait carriers in this population. Another objective was to describe a new screening technique for Sickle Cell Trait carriers.

Methods

This was a retrospective cohort study carried out at a private laboratory in the Southern Suburb of Beirut, Lebanon between 2002 and 2014. The sickling test was carried out for each patient using two methods: the classical “sodium metabisulfite sickling test”, and the new “sickling test method” used in the private lab. As a confirmatory test, hemoglobin electrophoresis was run on a random sample of 223 cases which were found to be positive using the two sickling tests.

Results

A total of 899 cases were found to be positive for the sickle cell trait out of 184,105 subjects screened during the 12-year period, prevalence = 0.49% (95% CI: 0.46 – 0.52). Among the total sample, females were found to have higher prevalence, where no time trend over the studied period was noted. The haemoglobin electrophoresis method confirmed the results of this new sickling test technique among the random sample of the 223 cases.

Conclusion

We found that the prevalence of sickle cell trait is lower as compared to other Arab countries, higher in females, with no significant time trend. The sickle cell test was found to be an accurate, simple and cheap test that could be easily added as a requirement for the pre-marital testing to screen for Sickle Cell Trait carriers.

Hepatobiliary Complications of Sickle Cell Disease among Children Admitted to Al Wahda Teaching Hospital, Aden, Yemen

OBJECTIVES

This study aimed to describe the pattern of hepatobiliary complications among patients with sickle cell disease (SCD) and to assess their correlation with age, gender and other risk factors.

METHODS

This cross-sectional study assessed 106 patients with SCD who were admitted to Al Wahda Teaching Hospital in Aden, Yemen, between January and June 2009. A full history, thorough examination, essential laboratory investigations (including a complete blood count, liver function test and viral markers test) and an abdominal ultrasound were performed on all patients. The clinicopathological characteristics of the hepatobiliary complications were analysed for their correlation to different risk factors such as age and gender.

RESULTS

It was found that 46.2% of the patients with SCD had hepatobiliary complications. Of these, 36.7% had viral hepatitis, 26.0% had cholecystitis and 20% had gallstones. A total of 60.4% of the affected patients were male. The mean levels of alanine aminotransferase (59.4 and 56.0 U/L) and aspartate transaminase (40.1 and 38.3 U/L) were significantly elevated in patients with viral hepatitis and cholecystitis, respectively. Hepatitis B virus surface antigen showed higher positivity (10.4%) than anti-hepatitis A and anti-hepatitis C antibodies. Hepatobiliary complications increased significantly with age and were notably higher among those who were often admitted to hospital and/or underwent frequent blood transfusions.

CONCLUSION

This study suggests that hepatobiliary complications are common among SCD patients and the likelihood of developing such complications increases as patients age. Thus, regular clinical follow-ups, abdominal ultrasound studies and periodic liver function tests, as well as serological tests for viral hepatitis, are strongly recommended. These can help in the early detection of these complications and allow opportunities for their management and prevention.

Incidence of sickle cell disease and other hemoglobin variants in 10,095 Lebanese neonates

Hemoglobinopathies are highly prevalent diseases and impose a public health burden. Early diagnosis and treatment can ameliorate the course of these diseases and improve survival. Despite purported high incidence of hemoglobinopathies in Lebanon, there are no nationwide screening programs. In this study, newborn screening utilizing high pressure liquid chromatography was executed in all public hospitals across Lebanon between 2010 and 2013. All newborns with an abnormal hemoglobin (Hb) were offered genetic counseling and all those with disease were enrolled in comprehensive hemoglobinopathy clinics. Among newborns, 2.1% were found to have an abnormal Hb variant with sickle Hb being the most common while 0.1% were found to have sickle cell disease (SCD). The majority of those with SCD had non-Lebanese origins. The most common causes of hospitalizations in infants with SCD were acute splenic sequestration and pain crises. No bacteremia or other life threatening infections were noted. At a median follow up 14 months (follow up range 7 to 34 months), all children with disease are alive and compliant with treatment. Systematic screening for SCD and other Hb variants was shown to be feasible, cost effective, and of accurate predictive value. This program was also clinically effective because it led to the identification of babies with disease and to providing them with free early multidisciplinary care. Conclusively, a newborn screening program should be implemented across Lebanon to detect hemoglobinopathies and initiate early therapeutic and preventive strategies and genetic counseling.

Proposed low-cost premarital screening program for prevention of sickle cell and thalassemia in Yemen

In Yemen, the prevalence of sickle cell trait and β-thalassemia trait are high. The aim of this premarital program is to identify sickle cell and thalassemia carrier couples in Yemen before completing marriages proposal, in order to prevent affected birth. This can be achieved by applying a low-cost premarital screening program using simple blood tests compatible with the limited health resources of the country. If microcytosis or positive sickle cell is found in both or one partner has microcytosis and the other has positive sickle cell, so their children at high risk of having sickle cell or/and thalassemia diseases. Carrier couples will be referred to genetic counseling. The outcomes of this preventive program are predicted to decrease the incidence of affected birth and reduce the health burden of these disorders. The success of this program also requires governmental, educational and religious supports.

Characteristics of sickle cell anemia in Yemen

We studied 136 males and 105 females with sickle cell anemia to determine the characteristics of the disease in Yemen. Their mean age [± SD (standard deviation)] was 12.8 ± 9.5 years (range: 9 months-40 years). Taiz, Hudaydah and Hajjah governorates, in the South-Central and the Northwestern provinces, showed the highest prevalence. Eighty percent of the patients had family history of the disease, 73.0% patients had history of parental consanguinity and 20.7% of death of relative(s) due to the disease; 5.4% patients were older than 30 years of age. Pain, jaundice and infection were the most frequent features. Splenomegaly, cholelithiasis, osteomyelitis, acute chest syndrome (ACS), osteonecrosis and stroke occurred in 12.0, 9.5, 8.7, 6.6, 6.6 and 2.9%, respectively. Priapism and leg ulcers were rare. The mean laboratory values (obtained in the steady state) were: hemoglobin (Hb) 7.9 g/dL, WBC 14.08 × 10(9)/L, platelet 460 × 10(9)/L, reticulocytes 14.5%, lactate dehydrogenase (LDH) 597 U/L, Hb F (α2γ2) 16.69%, Hb S [β6(A3)Glu→Val, GAG>GTG] 77.31% and Hb A(2) (α2δ2) 1.47%, respectively. There was no significant difference between South-Central and Northwestern provinces regarding clinical events and hematological parameters.

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.

Thalassemia trait in outpatient clinics of Sana'a City, Yemen

Blood samples were collected from 699 patients attending out patient clinics in Sana'a City, Yemen, to obtain some idea of the prevalence of the thalassemias in our country. Complete blood count, hemoglobin (Hb) electrophoresis, quantitation of Hb A(2) and Hb F, and serum ferritin were determined. Microcytic, hypochromic red cells were found in 103 subjects (14.7%). Iron deficiency alone accounted for only a small proportion of these (n = 12), whereas features suggestive of beta-thalassemia (beta-thal) were present in 31 patients (4.43%) and features suggestive of alpha-thal trait were found in 60 patients (8.6%). The study showed that thalassemia probably accounts for most red cell microcytosis in these out patient clinics, and could represent a significant health problem through births of homozygotes and compound heterozygotes with severe disorders. This pilot study should be repeated with improved technology, and extended to include globin gene analysis to define the nature of the disorders that remain poorly diagnosed.

Clinical profile of sickle cell disease in Yemeni children

The clinical spectrum of sickle cell disease (SCD) in the Arabian Peninsula varies widely. This is the first report in Yemeni children.

METHODS

A hospital-based, cross-sectional study was undertaken in Al-Wahada Teaching Hospital in Aden of children under 16 years with homozygous (SS) SCD.

RESULTS

Fifty-six (55%) were males. There were clinical manifestations in 20% by the age of 6 months and in 67%, 88% and 92% by 1, 2 and 3 years, respectively. Dactylitis (hand-foot syndrome) was the most common presenting symptom and occurred in 54% of cases, followed by acute respiratory infections and other acute febrile illnesses. The main causes of hospitalisation were painful crisis (36%), anaemic crisis (16%) and acute chest syndrome (11%). Hepatomegaly was detected in 72% and splenomegaly in 40%. Cerebrovascular accident, cholelithiasis, hepatic crisis and leg ulcers each occurred in about 5% of patients. There was first- and second-degree consanguinity in 31% and 16%, respectively, of patients' families.

CONCLUSION

SCD is a serious problem, affecting children in Yemen from an early age. Disease course and severity were similar to that in Africans and American blacks and some reports from western Saudi Arabia. A screening programme linked to comprehensive medical care and genetic counselling is required to improve management and quality of life.