Introduction Malaria is associated with high morbidity during pregnancy. Homozygous sickle cell pregnant women are even more exposed during complicated malaria. The objective of the study was to ...evaluate the maternal and fetal morbidity of homozygous sickle cell pregnant pregnant women with complicated malaria. Methods We conducted a retrospective case-control study of 982 pregnancies in sickle cell pregnant women, during which a group of sickle cell pregnant women who received antimalarial chemoprophylaxis was compared to another group without chemoprophylaxis. We analyzed the clinical evolution of pregnant women (VOCs and transfusions, pregnancy weight gain) and parasite (parasite density at the time of diagnosis of complicated malaria and during treatment for three days). We analyzed the parameters of newborns at birth (age of pregnancy at the time of delivery, birth weight, weight of the placenta and histopathological examination of the placenta. Results Out of 982 pregnancies, 15% of pregnant women suffered from complicated malaria, 57% suffered from uncomplicated malaria and 28% did not suffer from malaria. Pregnancy weight gain, birth weight, was better in the group of pregnant women who received chemoprophylaxis and the placenta had less histological lesions. Parasite density was low. There was a significant positive correlation between parasite density and the number of CVOs and transfusions and between parasite density and histological lesions of the placenta and low birth weight. Conclusion Complicated malaria is associated with high maternal and fetal morbidity in sickle cell patients. Malaria chemoprophylaxis can reduce maternal and fetal complications and parasite density during malaria infection.
Sickle cell anemia (SCA) is a monogenic hemoglobinopathy associated with severe acute and chronic complications, with the highest incidence worldwide in Sub-Saharan Africa. The wide variability in ...clinical manifestations suggest that a uniform response to hydroxurea may not be attained. In view of a potential treatment with hydroxyurea (HU), we assessed the variability of clinical and hematological manifestations in a cohort of adults with SCA in Kinshasa, capital of the DR Congo in Central Africa.
A cross-sectional study was conducted in a hospital dedicated to SCA management in Kinshasa. Clinical history of patients was recorded, a complete physical examination performed. The diagnosis was confirmed by means of DNA analysis. A full blood count and hemolysis markers were measured. The severity of the disease was evaluated by means of a previously reported score.
The study group consisted of 166 genetically confirmed SCA patients. The SCA severity was mild in 28.9%, moderate in 64.5% and severe in 6.6%. The disease severity score increased with patient's age (p ≤ 0.001). The severity was higher in males compared to females (p = 0.012). In males, the severity score was correlated with the presence of priapism (p = 0.045), a manifestation not previously incorporated in the severity score. The severity score was inversely correlated with the fetal hemoglobin (HbF) rate (p = 0.005). Malnutrition (BMI <18.5 kg/m2) was present in 47% of patients and was related to the male sex, hip disease (aOR 3.11; p = 0.019) and severe phenotype (aOR 3.53; p = 0.012). Leg ulcers were more frequent in males than in females (p = 0.001; OR 24.3) and were correlated with the number of days of hospitalization (p = 0.029). Hip disease was related to the increasing age (p = 0.008).
In this selected, hospital-based populations of adults with SCA, severe disease was rare, which may be due to survival bias. However, two thirds had moderate severity of the disease, mostly with a low HbF, and they may benefit from HU treatment. In the Central-African setting the separation between vaso-occlusive and hyperhemolytic sub-phenotypes was not applicable.
To determine the incidence and risk factors of occurrence of non-syndromic cleft lip and/or cleft palate (NSCLP) in Lubumbashi.
A case-control study was conducted in the health district of Lubumbashi ...from February 2012 to December 2015. An exhaustive sampling, collecting all newborns with cleft lip and/or cleft palate (CL ± P) in maternity wards was conducted. From a total of 172 cases, 162 non-syndromic cases were recruited. For each case, one clinically normal newborn control was selected.
NSCLP had an incidence of 1/1258 live births (0.8/1000). We found significant associations with a family history of cleft lip and palate (CLP) (x
= 11.5, p = 0.0007), maternal alcohol intake (OR = 19.3, 95% CI: 1.9-197.1), paternal alcohol during the periconceptional period and the first trimester of pregnancy (OR = 18.7, 95% CI: 3.9-89.2), maternal educational level lower than high school (OR = 9.5, 95% CI: 2.0-44.7), clay (Pemba) consumption during pregnancy (OR = 38.3, 95% CI: 9.3-157.0), the use of insecticides in the evening (OR = 130.3, 95% CI: 13.2-1286.9), indoor cooking with charcoal (Makala) (OR = 6.5, 95% CI: 1.22-34.5), and regular consumption of Kapolowe fish, supposedly contaminated with heavy metals (OR = 29.5, 95% CI: 7.4-116.7).
Several environmental risk factors highly prevalent in Central Africa for facial clefting were found.
The evaluation of dysmorphism is often subjective because many continuous traits are not easily measured or lack normal values. Because many common morphologic profiles vary between populations, ...population-specific reference ranges of relevant traits are needed. We aim to evaluate the objective assessment of facial dysmorphism in 553 Congolese newborns based on facial measurements. Measurements taken with a ruler were on average larger compared to those with a caliper, but the bias did not depend on the size of the measurement. We therefore introduced a correction factor that allows to use both techniques for facial measurements interchangeably in future studies. The outer canthal distance, palpebral fissure length, and mouth width were significantly larger in Congolese newborns (respectively mean 6.59 SD 0.48; mean 2.20 SD 0.24; mean 2.78 SD 0.26) when compared to references based on European newborns (respectively mean 3.59 SD 1.76; mean 4.20 SD 2.26; mean 0.47 SD 1.21), while the rest of measurements were significantly smaller. The interpupillary distance (IPD) calculated from inner canthal distance and outer canthal distance was not significantly different. We observed a poor agreement between clinical evaluation and measured features (kappa of 0.432). Clinicians were more likely to recognize a face as having wide-spaced eyes when it had been recognized as such during the clinical examination, more than if the child had a high interpupillary distance. This suggests that the measured IPD is not precisely reflecting what is clinically evaluated as wide-spaced eyes.
The evaluation of minor physical variation is crucial in a dysmorphological examination. Currently, data on the spectrum and incidence of minor physical variants in Central African newborns is ...lacking. We therefore conducted a cross-sectional descriptive study of 722 newborns recruited within the first 24 hr of life, in two large maternities in Kinshasa, DR Congo. Minor anomalies were defined according to the series of articles in AJMG Part A and coded as human phenotype ontology terms. A total of 97 different morphological variants were recorded of which 13 were common. About 34.8% of the newborn carried one minor anomaly, 11.6% had two, and 4.3% had three minor anomalies. No gender differences were observed, but the incidence of specific anomalies appeared to vary with the geographical origin of parents within the DR Congo. The results of this study will aid clinicians to interpret morphological variation in Central African newborns.
IntroductionMalaria is associated with high morbidity during pregnancy. Homozygous sickle cell pregnant women are even more exposed during complicated malaria. The objective of the study was to ...evaluate the maternal and fetal morbidity of homozygous sickle cell pregnant pregnant women with complicated malaria.MethodsWe conducted a retrospective case-control study of 982 pregnancies in sickle cell pregnant women, during which a group of sickle cell pregnant women who received antimalarial chemoprophylaxis was compared to another group without chemoprophylaxis. We analyzed the clinical evolution of pregnant women (VOCs and transfusions, pregnancy weight gain) and parasite (parasite density at the time of diagnosis of complicated malaria and during treatment for three days). We analyzed the parameters of newborns at birth (age of pregnancy at the time of delivery, birth weight, weight of the placenta and histopathological examination of the placenta.ResultsOut of 982 pregnancies, 15% of pregnant women suffered from complicated malaria, 57% suffered from uncomplicated malaria and 28% did not suffer from malaria. Pregnancy weight gain, birth weight, was better in the group of pregnant women who received chemoprophylaxis and the placenta had less histological lesions. Parasite density was low. There was a significant positive correlation between parasite density and the number of CVOs and transfusions and between parasite density and histological lesions of the placenta and low birth weight.ConclusionComplicated malaria is associated with high maternal and fetal morbidity in sickle cell patients. Malaria chemoprophylaxis can reduce maternal and fetal complications and parasite density during malaria infection.
Oculocutaneous albinism (OCA) is an autosomal recessive genetic disorder associated with reduced or absent pigmentation in the skin, hair and eyes. OCA type 2 (OCA2) is the most common type in ...Sub-Saharan Africa, related to a recurrent 2.7 kb intragenic deletion. Genomic data from Congolese patients are lacking. We aimed to describe genetic causes of OCA2 in a cohort of Congolese persons with OCA, and explore possible genotype-phenotype correlations.
A cross sectional study was conducted from January 2015 to December 2017 in Kinshasa, Democratic Republic of Congo (DRC). 165 Congolese unrelated families with non-syndromic OCA, identified through patients' associations, consented to participate to this study. All index cases were tested for the known 2.7 kb deletion involving the exon 7 of the OCA2 gene. Patients heterozygous for the deletion underwent Sanger sequencing of all exons and flanking sequences in the OCA2 gene. Family segregation was performed for candidate pathogenic variants.
The 2.7 kb deletion in the OCA2 gene was identified in 136/165 (82.4%) index cases, including 113 (68.5%) homozygotes and 23 (13.9%) heterozygotes. Sanger sequencing identified a pathogenic or likely pathogenic variant in the OCA2 gene in 12 out of 23 heterozygotes investigated (52.1%). Segregation analysis allowed us to locate the point mutation on the trans allele in the three patients from whom parental DNA was available.
The OCA2 2.7 kb deletion is the major cause of non-syndromic OCA in Congolese patients recruited in this study, confirming results from other Sub-Saharan African populations. Several additional mutations were detected in OCA patient's heterozygote for the deletion, with to date no evidence for a second frequent founder mutation. The confirmation of a single mutation as the major cause will facilitate genetic counselling in this country.
Sickle cell anemia is an inflammatory disease and is characterized by chronic hemolysis. We sought to evaluate the association of lactate dehydrogenase levels with specific clinical phenotypes and ...laboratory variables in patients with sickle cell anemia.
The present cross-sectional study was conducted in Sickle Cell Centre of Yolo in Kinshasa, the Democratic Republic of Congo. Two hundred and eleven patients with Sickle Cell Anemia in steady state were recruited. Seventy-four participants with normal Hb (Hb-AA) were selected as a control group.
The average rates of hemoglobin, hematocrit, and red blood cells tended to be significantly lower in subjects with Hb-SS (p<0.001). The average rates of white blood cells, platelets, reticulocytes and serum LDH were significantly higher in subjects with Hb-SS (p<0.001). The average rates of Hb, HbF, hematocrit and red blood cells of Hb-SS patients with asymptomatic clinical phenotype were significantly higher than those of the two other phenotypes. However, the average rates of white blood cells, platelets, reticulocytes, and LDH of Hb-SS patients with the severe clinical phenotype are higher than those of two other clinical phenotypes. Significant correlations were observed between Hb and white blood cell in severe clinical phenotype (r3 = -0.37 *) between Hb and red blood cells in the three phenotypes (r1 = 0.69 * r2 * = 0.69, r3 = 0.83 *), and finally between Hb and reticulocytes in the asymptomatic clinical phenotype and severe clinical phenotype (r1 = -0.50 * r3 = 0.45 *). A significant increase in LDH was observed in patients with leg ulcer, cholelithiasis and aseptic necrosis of the femoral head.
The increase in serum LDH is accompanied by changes in hematological parameters. In our midst, serum LDH may be considered as an indicator of the severity of the disease.
Blackwater fever (BWF), one of the most severe and life-threatening forms of falciparum malaria, is characterized by acute massive intravascular haemolysis, often leading to acute renal failure. Thus ...far, the genetics of the underlying susceptibility to develop BWF is not fully elucidated. Deficiency in the MBL protein, an important component of the innate immune system, has previously been suggested to be a susceptibility factor for the development of severe malaria. This study aimed to evaluate the association between MBL2 gene polymorphisms, known to affect the MBL protein level/activity, and the occurrence of BWF among Congolese children.
This is a case-control study. Cases were patients with BWF, whereas controls, matched for gender and age, had uncomplicated malaria (UM). Dried blood spot was collected for genotyping.
A total of 129 children were screened, including 43 BWF and 86 UM. The common allele in BWF and UM was A, with a frequency of 76.7 and 61.0%, respectively (OR: 2.67 (0.87-829) and p = 0.079). The frequency of the C allele was 18.6 and 29.1% in BWF and UM groups, respectively, with p = 0.858. Not a single D allele was encountered. Genotype AA was at higher risk for BWF whereas genotypes A0 (AB and AC) were over-represented in UM group (OR: 0.21 (0.06-0.78)) with p = 0.019. Nine haplotypes were observed in this study: 3 high MBL expression haplotypes and 6 low MBL expression haplotype. One new haplotype HYPC was observed in this study. None of these haplotypes was significantly associated with BWF.
This pilot study is a preliminary research on MBL2 gene and infectious diseases in DRC. The study results show a higher risk for BWF in AA. This suggests that future studies on BWF should further investigate the contribution of a strong immune response to the occurrence of BWF.
Background
Sickle‐cell anemia (SCA) is the most common genetic disease worldwide caused by a single mutation in the gene HBB. DNA testing can help to clarify the diagnosis when Hb electrophoresis is ...inconclusive. We evaluated the usefulness and feasibility of DNA‐based diagnosis of SCA in rural Central Africa.
Methods
This is a cross‐sectional study conducted from November 2016 to end October 2017 in the Hôpital Saint Luc de Kisantu, located 120 km from Kinshasa. This hospital offers the management of SCA patients, mainly identified using the Sickling test (Emmel test) combined with clinical features. We included patients aged 6 months to 18 years locally diagnosed as SCA, and we collected clinical and hematological data. All patients were offered Hb electrophoresis and DNA testing at the Center for Human Genetics of the University of Kinshasa.
Results
This study included 160 patients. Hemoglobin capillary electrophoresis suggested that 136 (85%) were homozygote SS, 13 (8.1%) were heterozygote (AS), and 11 (6.9%) were homozygote normal (AA). DNA testing confirmed these electrophoresis findings, with the exception of four patients, two AS in electrophoresis were found SS due to recent transfusion, and two SS in electrophoresis were found AS because they have compound heterozygous form S/β°‐thalassemia. The diagnosis of SCA was therefore wrongly ascertained with Emmel test in 15% of patients.
Conclusion
This study reveals a high proportion of false‐positive SCA diagnoses in a rural environment in Central Africa. This underlines the importance of DNA testing in conjunction with Hb electrophoresis.
This study included 160 patients. Hemoglobin capillary electrophoresis suggested that 136 (85%) were homozygote SS, 13 (8.1%) were heterozygote (AS), and 11 (6.9%) were homozygote normal (AA). DNA testing confirmed these electrophoresis findings, with the exception of four patients, two AS in electrophoresis were found SS due to recent transfusion, and two SS in electrophoresis were found AS because they have compound heterozygous form S/β°‐thalassemia. The diagnosis of SCA was therefore wrongly ascertained with Emmel test in 15% of patients.