Determinants of the haemoglobin level in patients with sickle cell disease living in sub-Saharan Africa: Major impact of the country of residence and independent effects of leucocyte and platelet counts and haemolysis.

The degree of anaemia in sickle cell disease (SCD) is a well-known contributor to morbidity and mortality. We aimed to explore the factors affecting haemoglobin (Hb) level in African SCD patients, considering haemolysis biomarkers (LDH and bilirubin level, and reticulocyte count), leucocyte and platelet counts and socio-demographic characteristics (gender, age group, country of residence and BMI). The research was part of the CADRE multinational cohort and involved 3699 SCD patients living in Mali, Senegal, Ivory Coast, Democratic Republic of Congo, Gabon and Cameroon: 2936 SS/Sß0, 587 SC and 176 Sß + patients with median Hb level of 8, 11.3 and 11.2 g/dL respectively (p < 0.001). In multivariate analysis conducted in 1394 SS/Sß0 patients, living in Cameroon, female gender, lower BMI, higher haemolysis markers (especially LDH) and higher leucocyte and platelet counts were independently associated with lower Hb level (all p < 0.05). In 497 SC and 156 Sß + patients, female gender (p < 0.001), lower BMI (p < 0.05) and higher platelet counts (p < 0.001) were independently associated with lower Hb level. Anaemia in African SCD patients is not only associated with haemolysis but also with the country of residence, lower BMI and leucocyte or platelet counts which might reflect inflammation related to infectious burden in the region.

Decrease in Hospitalizations and Increase in Deaths during the Covid-19 Epidemic in a Pediatric Hospital, Yaounde-Cameroon and Prediction for the Coming Months.

BACKGROUND: The COVID-19 pandemic reached Cameroon in March, 2020. The aim of this study was to unveil the consequences of this pandemic on hospitalizations and on mortality in a pediatric hospital. Methods: A descriptive and retrospective cross-sectional study was carried out using hospitalization and death statistics collected from a pediatric hospital. We compared the data before and after the pandemic and made predictions for the next 12 months. Results: A drastic drop in hospitalizations was noted coinciding with the partial lockdown in Cameroon. Paradoxically, at the same time, the number of deaths per month doubled though the causes remained the same as in the past. Conclusion: The COVID-19 pandemic was marked by drop in hospitalizations and paradoxically, an increase in child mortality. These deaths were probably due not to SARS-Cov-2 infection, but rather due to the usual illnesses whose management was delayed, a probable consequence of the confinement.

Degree of anemia, indirect markers of hemolysis, and vascular complications of sickle cell disease in Africa.

The hyperhemolysis paradigm that describes overlapping "hyperhemolytic-endothelial dysfunction" and "high hemoglobin-hyperviscous" subphenotypes of sickle cell disease (SCD) patients is based on North American studies. We performed a transversal study nested in the CADRE cohort to analyze the association between steady-state hemolysis and vascular complications of SCD among sub-Saharan African patients. In Mali, Cameroon, and Ivory Coast, 2407 SCD patients (1751 SS or sickle ß-zero-thalassemia [Sß0], 495 SC, and 161 sickle ß+-thalassemia [Sß+]), aged 3 years old and over, were included at steady state. Relative hemolytic intensity was estimated from a composite index derived from principal component analysis, which included bilirubin levels or clinical icterus, and lactate dehydrogenase levels. We assessed vascular complications (elevated tricuspid regurgitant jet velocity [TRV], microalbuminuria, leg ulcers, priapism, stroke, and osteonecrosis) by clinical examination, laboratory tests, and echocardiography. After adjustment for age, sex, country, and SCD phenotype, a low hemoglobin level was significantly associated with TRV and microalbuminuria in the whole population and with leg ulcers in SS-Sß0 adults. A high hemolysis index was associated with microalbuminuria in the whole population and with elevated TRV, microalbuminuria, and leg ulcers in SS-Sß0 adults, but these associations were no longer significant after adjustment for hemoglobin level. In conclusion, severe anemia at steady state in SCD patients living in West and Central Africa is associated with elevated TRV, microalbuminuria, and leg ulcers, but these vascular complications are not independently associated with indirect markers of increased hemolysis. Other mechanisms leading to anemia, including malnutrition and infectious diseases, may also play a role in the development of SCD vasculopathy.

Arterial Stiffness Impairment in Sickle Cell Disease Associated With Chronic Vascular Complications: The Multinational African CADRE Study.

BACKGROUND: Although a blood genetic disease, sickle cell disease (SCD) leads to a chronic vasculopathy with multiple organ involvement. We assessed arterial stiffness in SCD patients and looked for associations between arterial stiffness and SCD-related vascular complications. METHODS: The CADRE (Coeur Artères et Drepanocytose, ie, Heart Arteries and Sickle Cell Disease) study prospectively recruited pediatric and adult SCD patients and healthy controls in Cameroon, Ivory Coast, Gabon, Mali, and Senegal. Patients underwent clinical examination, routine laboratory tests (complete blood count, serum creatinine level), urine albumin/creatinine ratio measure, and a measure of carotid-femoral pulse wave velocity (cf-PWV) and augmentation index (AI) at a steady state. The clinical and biological correlates of cf-PWV and AI were investigated by using a multivariable multilevel linear regression analysis with individuals nested in families further nested in countries. RESULTS: Included were 3627 patients with SCD and 943 controls. Mean cf-PWV was lower in SCD patients (7.5±2.0 m/s) than in controls (9.1±2.4 m/s, P<0.0001), and lower in SS-Sß(0) than in SC-Sß(+) phenotypes. AI, corrected for heart rate, increased more rapidly with age in SCD patients and was higher in SCD than in control adults. cf-PWV and AI were independently associated with age, sex, height, heart rate, mean blood pressure, hemoglobin level, country, and hemoglobin phenotype. After adjustment for these correlates, cf-PWV and AI were associated with the glomerular filtration rate and osteonecrosis. AI was also associated with stroke, pulmonary hypertension, and priapism, and cf-PWV was associated with microalbuminuria. CONCLUSIONS: PWV and AI are deeply modified in SCD patients in comparison with healthy controls. These changes are independently associated with a lower blood pressure and a higher heart rate but also with the hemoglobin phenotype. Moreover, PWV and AI are associated with several SCD clinical complications. Their prognostic value will be assessed at follow-up of the patients.

The Acute Chest Syndrome in Cameroonian children living with sickle cell disease.

BACKGROUND: Although sub-Saharan Africa (SSA) is particularly affected by sickle cell disease (SCD), there is dearth of research on this topic in the region, specifically targeting the magnitude of SCD-related complications. We therefore conducted this study to determine the burden of acute chest syndrome (ACS) and describe its clinical and therapeutic aspects among SCD children in Cameroon, a SSA country. METHODS: This was a retrospective study carried-out from September 2013 to June 2014 at the SCD unit of the Mother and Child Centre of the Chantal Biya Foundation, a pediatric reference centre in Yaoundé, Cameroon. We enrolled all SCD children with confirmed diagnosis of ACS, and recorded their clinical presentation at admission along with their evolution during hospitalization. RESULTS: Twenty one cases of ACS were identified during the study period, from 338 hospitalizations of children with SCD. Ages ranged from 11 months to 16 years with a mean (standard deviation) of 5.5 (3.4) years, and a male/female sex ratio of 3.2/1. We noticed relatively low levels of HbF, from 6.4 to 21.9% with a mean of 14.6% (6.0%). The three main symptoms at admission were fever (90.5%), cough (81%) and chest pains (28.6%). Two patients (9.5%) developed ACS 2 days after admission. The mean values of leukocytes, neutrophils, serum CRP, serum LDH and hemoglobin were respectively 32479.4 (17862.3)/mm(3), 23476 (11543.7)/mm(3), 228.2 (132.6) mg/l, 3452.3 (2916.3) IU/l and 6.5 (1.2) g/dl. The main localizations of radiological alveolar consolidations were the lower lobes (90.5%). Treatment associated broad-spectrum antibiotics (100%), hydration (100%), analgesics (43.2%), whole blood transfusion (66.7%), and oxygen supplementation (33.3%). Blood transfusion significantly improved hemoglobin level (p = 0.039). The duration of hospitalization, the mean of which was 6.8 (3.1) days, was influenced by none of the tested variables (all p values > 0.05). CONCLUSION: ACS is frequent among SCD children in our milieu. Its etiologies seem to be multifactorial. Patients' parents should be educated to recognize early signs and symptoms of the disease, and consult rapidly. Additionally, clinicians must be trained to diagnose ACS, and manage it promptly and efficiently to avoid its related catastrophic consequences.

Initiating the first rheumatic heart disease clinic in Cameroon: A descriptive study.

Background and Aim: Rheumatic heart disease (RHD) is a significant cause of heart failure in sub-Saharan Africa. The causes of death from RHD are multiple, many of which can be prevented with appropriate follow-up of patients and effective secondary prophylaxis. An RHD Clinic was initiated to attempt a solution in Yaoundé, Cameroon. Over 6 months, its impact was evaluated. Methods: Two echocardiography registers were accessed, and patients diagnosed with RHD between 2005 and 2018 were contacted. Consenting carers and patients pioneered the first RHD Clinic. Activities of the clinic comprised health education, medical visits, and benzylpenicillin G (BPG) injections. Text messages and phone calls were used to remind patients of their monthly appointments. Results: Out of 1200 first-time cardiac ethnographies, 70 patients (5.83%) had been diagnosed with RHD. The case fatality rate of RHD was 16.67%. Twenty-three patients were successfully registered and followed-up by the clinic, 70% of whom were female. The age range was 4-22 years. Fifty-three percent had an NYHA score of 2 or more at the time of admission into the clinic. There was an increase in adherence to secondary prophylaxis with BPG from 42.9% at baseline to 87%-95% in the last 3 months. Conclusion: Our short experience running an RHD Clinic was marked by increased treatment adherence among persons living with RHC.

Pubertal patterns in children with sickle cell anemia: A case-control study in Cameroon.

BACKGROUND: Puberty may be impaired in children with sickle cell anemia (SCA). Therefore, we aimed to explore the clinical and hormonal features of puberty in Cameroonian children. METHODS: In a case-control study, we included 64 children aged 8-18 years with SCA matched to healthy controls. We assessed height, weight, body mass index, body composition, and Tanner stages. Hormonal measurements included anti-mullerian hormone, follicle-stimulating hormone, luteinizing hormone, and sex hormones (estrogens/testosterone). We used the Mann-Whitney Wilcoxon test to compare the median values between cases and controls. We looked for associations between the severity criteria of SCA and delayed puberty through multivariate analysis. RESULTS: Delayed puberty was reported in 27.3% of girls and 10% of boys with SCA. The median age of menarche was delayed by 2 years compared to controls. SCA patients had a low lean body mass compared to controls (p = 0.03). Anti-mullerian hormone levels were significantly higher in boys with SCA than those of controls (45.9 ng/mL vs. 17.65 ng/mL; p = 0.018). A history of severe infection, acute chest syndrome, and low hemoglobin level was associated with delayed sexual maturation in children with SCA. CONCLUSION: Our study revealed delayed puberty in children with SCA. Moreover, puberty is affected by the severity of the disease. This highlights the importance of regular monitoring of puberty during the follow-up of these children.

Artesunate-mefloquine combination therapy in acute Plasmodium falciparum malaria in young children: a field study regarding neurological and neuropsychiatric safety.

BACKGROUND: Mefloquine-artesunate combination therapy for uncomplicated falciparum malaria is one of the treatments used in African children. Data concerning neurological safety in adults and children treated with mefloquine and artesunate combination therapy is well documented in Asia. Safety data for neurological and neuropsychiatric side effects of mefloquine and artesunate combination therapy in African children are scarce, although WHO recommends this therapy in Africa. METHODS: A phase IV, open label, single arm study was conducted among African children between 10 and 20 kg with acute uncomplicated falciparum malaria. They were treated over three consecutive days with a paediatric fixed-dose combination of artesunate (50 mg/d) and mefloquine (125 mg/d). Parasitological, clinical and neurological examinations and standardized questions about neuropsychiatric symptoms were carried out on days 0, 4, 7, 28 and 63. The primary objective was to assess the neurological and neuropsychiatric safety of artesunate-mefloquine combination therapy in young children. RESULTS: From December 2007 to March 2009, 220 children with uncomplicated Plasmodium falciparum malaria were treated with artesunate and mefloquine. 213 children were analysed according to study protocol. 50 neurological and neuropsychiatric adverse events occurred in 28 patients. Eleven drug-related neurological and neuropsychiatric adverse events occurred in eight patients. Sleeping disorders were present in 2.3%, neurological disorders in 1.4%, neuropsychiatric disorders in 1% and eating disorders in 0.5% of the patients. Adverse events were of mild to moderate intensity and resolved spontaneously. CONCLUSION: African children showed a low percentage of self-limited neurological and neuropsychiatric adverse events, confirming studies on neurological safety in Asian children treated with artesunate and mefloquine. Sleeping disorders were most frequently observed.

DMD-related muscular dystrophy in Cameroon: Clinical and genetic profiles.

BACKGROUND: Most of the previous studies on Duchenne Muscular Dystrophy (DMD) were conducted in Caucasian, Asian, and Arab populations. Therefore, little is known about the features of this disease in Africans. In this study, we aimed to determine the clinical characteristics of DMD, and the common mutations associated with this condition in a group of Cameroonian patients. METHODS: We recruited DMD patients and performed a general physical examination on each of them. Multiplex ligand-dependant probe amplification was carried out to investigate exon deletions and duplications in the DMD gene (OMIM: 300377) of patients and their mothers. RESULTS: A total of 17 male patients from 14 families were recruited, aged 14 ± 5.1 (8-23) years. The mean age at onset of symptoms was 4.6 ± 1.5 years, and the mean age at diagnosis was 12.1 ± 5.2 years. Proximal muscle weakness was noted in all patients and calf hypertrophy in the large majority of them (88.2%; 15/17). Flexion contractures were particularly frequent on the ankle (85.7%; 12/14). Wasting of shoulder girdle and thigh muscles was present in 50% (6/12) and 46.2% (6/13) of patients, respectively. No patient presented with hearing impairment. Deletions in DMD gene (OMIM: 300377) occurred in 45.5% of patients (5/11), while duplications were observed in 27.3% (3/11). Both mutation types were clustered between exons 45 and 50, and the proportion of de novo mutation was estimated at 18.2% (2/11). CONCLUSION: Despite the first symptoms of DMD occurring in infancy, the diagnosis is frequently made later in adolescence, indicating an underestimation of the number of cases of DMD in Cameroon. Future screening of deletions and duplications in patients from Cameroon should focus on the distal part of the gene.

[Mortality pattern in children aged 3-59 months hospitalized in the Intensive Care Unit at a Paediatric Center in Yaounde-Cameroon]. / Profil des décès survenus chez les enfants âgés de 3 à 59 mois dans l'unité des soins intensifs d'un centre pédiatrique à Yaoundé-Cameroun.

INTRODUCTION: mortality risk is high at the Intensive Care Units (ICU) in developing countries. We here report the deaths occurred in the ICU at the Mother and Child Center in Yaounde, Cameroon. METHODS: we conducted a retrospective study on the clinical, socio-demographic features, the therapeutic strategy as well as some of the factors associated with deaths occurred in 200 patients aged 3-59 months between 2010 and 2014. RESULTS: out of 2675 patients included in the study, 1807 were aged 3-59 months and 303 died. The overall and cause-specific mortality rate in this age group was 11.3% and 16.7% respectively. Most patients (152/200; 76.0%) died within 24 months and the median admission time was 7 days. More than half of patients (57.0%) presented to a health center and only 66 (33.0%) presented to a referral hospital. Severe malaria (41.5%), pneumonia (22.7%) and gastroenteritis (27.8%) were the most common diseases. Malnutrition and HIV/AIDS were the underlying causes of death in 23.0% and 20.5% of patients respectively. Gastroenteritis multiplied the risk of death of approximately 6 times (OR = 5.76; p = 0.000) in patients affected by malnutrition and HIV infection. Deaths mainly occurred (90.0%) within 72 hours of admission. CONCLUSION: despite limited resources, some diseases could have been easily treated avoiding complications which require reanimation. It is essential to intensify the fight against malaria, HIV infection and malnutrition.

A cross sectional study of growth of children with sickle cell disease, aged 2 to 5 years in Yaoundé, Cameroon.

INTRODUCTION: Growth of children affected by Sickle Cell Disease (SCD) is not well described in sub-Saharan Africa despite the high prevalence of the disease. Few data are available in this context and on the issue using the World Health Organization growth norms. We therefore conduct the present study with the aim of describing the growth of affected children aged less than 5 years. We also assessed correlation of anthropometric parameters with disease severity criteria. METHODS: A cross-sectional study was conducted during a period of 8 months, at the Mother and Child Center of Yaoundé. The sample included 77 children with SCD aged 2 to 5 years old in steady state. Anthropometric measurements and socio-demographic data were collected and analyzed. All statistical tests were two-tailed with p<0.05 considered significant. RESULTS: Median age of study population was 3.67 years. Low weight, height and weight for height Z-scores (<-2SD) were observed in 4%, 4%, and 5% of children, respectively. Projection of these parameters were stackable on WHO curves. Regression analysis indicated an association of low height-for-age and of low Body Mass Index (BMI)-for-age with age. CONCLUSION: This study demonstrates unexpectedly lower mean Z-score for weight, height and weight for height than reported while using WHO norms.

Prevalence and factors associated with hypertension in primary school children, in the centre region of Cameroon.

BACKGROUND: There has been a progressive increase in hypertension among children and adolescents over the years. Hypertension in childhood is influenced by various risk factors including; childhood obesity, lifestyle and hereditary factors. This study is aimed at assessing the prevalence of hypertension and elevated blood pressure (BP); as well as the associated factors to hypertension among primary school children in a rural setting in the, Centre Region of Cameroon. METHODS: A cross sectional study was carried out from November 2017 to May 2018 in 13 primary schools in Mbankomo subdivision. A two staged cluster sampling technique was used to select participants: the first stage we conveniently selected 13 out of 71 (18%) primary schools in the study area by probability proportionate to size since the subdivision does not have an equal number of primary schools in the rural and semi-urban areas. In the second stage, we also used probability proportional to size to randomly select participants from the 13 clusters because the classes did not have equal number of students. We randomly selected 13% pupils enrolled in each class of the 13 schools. BP and anthropometric measurements were taken, together with socio-demographic characteristics, lifestyle and past history. RESULTS: The overall prevalence of hypertension among the 822 pupils sampled was 1.6% (with 1.5% in stage I and 0.1% in stage II) and that of elevated BP was 8.1%, with a systolic predominance of 1.6%. SBP and DBP had a significant positive correlation with age (r=0.17; P=0.000 and r=0.07; P=0.000 respectively) and BMI (r=0.18; P=0.000 and r=0.11; P=0.000 respectively). The associated risk factors for hypertension were: the pupil's age >10 years (95% CI: 1.2581-33.1841; P=0.0254), family history of overweight (95% CI: 1.6906-32.9401; P=0.008), and excess weight (95% CI: 2.5094-40.7063; P=0.0011), and being born at term (P=0.0004) as a protecting factor. CONCLUSIONS: This study revealed a high prevalence of hypertension among primary school children in rural areas, with a number of preventable risk factors. Considering the risk factors found, children should be educated on proper nutrition, and the need for physical exercises at home and in school to avoid overweight and obesity.

Subclinical Cardiac Dysfunction Is Associated With Extracardiac Organ Damages.

Background: Several studies conducted in America or Europe have described major cardiac remodeling and diastolic dysfunction in patients with sickle cell disease (SCD). We aimed at assessing cardiac involvement in SCD in sub-Saharan Africa where SCD is the most prevalent. Methods: In Cameroon, Mali and Senegal, SCD patients and healthy controls of the CADRE study underwent transthoracic echocardiography if aged ≥10 years. The comparison of clinical and echocardiographic features between patients and controls, and the associations between echocardiographic features and the vascular complications of SCD were assessed. Results: 612 SCD patients (483 SS or Sß0, 99 SC, and 19 Sß+) and 149 controls were included. The prevalence of dyspnea and congestive heart failure was low and did not differ significantly between patients and controls. While left ventricular ejection fraction did not differ between controls and patients, left and right cardiac chambers were homogeneously more dilated and hypertrophic in patients compared to controls and systemic vascular resistances were lower (p < 0.001 for all comparisons). Three hundred and forty nine SCD patients had extra-cardiac organ damages (stroke, leg ulcer, priapism, microalbuminuria or osteonecrosis). Increased left ventricular mass index, cardiac dilatation, cardiac output, and decreased systemic vascular resistances were associated with a history of at least one SCD-related organ damage after adjustment for confounders. Conclusions: Cardiac dilatation, cardiac output, left ventricular hypertrophy, and systemic vascular resistance are associated with extracardiac SCD complications in patients from sub-Saharan Africa despite a low prevalence of clinical heart failure. The prognostic value of cardiac subclinical involvement in SCD patients deserves further studies.

Exercise-induced albuminuria vs circadian variations in blood pressure in type 1 diabetes.

AIM: To investigated the relationship between exercise-induced ambulatory blood pressure measurement (ABPM) abnormalities in type 1 diabetes mellitus (T1DM) adolescents. METHODS: We conducted a case-control at the National Obesity Center of the Yaoundé Central Hospital, Cameroon. We compared 24 h ABPM and urinary albumin-to-creatinine ratio (ACR) at rest and after a standardized treadmill exercise between 20 Cameroonian T1DM patients and 20 matched controls. T1DM adolescents were aged 12-18 years, with diabetes for at least one year, without proteinuria, with normal office blood pressure (BP) and renal function according to the general reference population. Non-diabetic controls were adolescents of general population matched for sex, age and BMI. RESULTS: Mean duration of diabetes was 4.2 ± 2.8 years. The mean 24 h systolic blood pressure (SBP) and diastolic blood pressure (DBP) were respectively 116 ± 9 mmHg in the diabetic group vs 111 ± 8 mmHg in the non-diabetic (P = 0.06), and 69 ± 7 mm Hg vs 66 ± 5 mm Hg (P = 0.19). There was no difference in the diurnal pattern of BP in diabetes patients and non-diabetic controls (SBP: 118 ± 10 mmHg vs 114 ± 10 mmHg, P = 0.11; DBP: 71 ± 7 mmHg vs 68 ± 6 mmHg, P = 0.22). Nighttime BP was higher in the diabetic group with respect to SBP (112 ± 11 mmHg vs 106 ± 7 mmHg, P = 0.06) and to the mean arterial pressure (MAP) (89 ± 9 mmHg vs 81 ± 6 mmHg, P = 0.06). ACR at rest was similar in both groups (5.5 mg/g vs 5.5 mg/g, P = 0.74), but significantly higher in diabetes patients after exercise (10.5 mg/g vs 5.5 mg/g, P = 0.03). SBP was higher in patients having exercise-induced albuminuria (116 ± 10 mmHg vs 108 ± 10 mmHg, P = 0.09). CONCLUSION: Exercise-induced albuminuria could be useful for early diagnosis of kidney damage in adolescents with T1DM.

Exercise-induced albuminuria and circadian blood pressure abnormalities in type 2 diabetes.

AIM: To investigate the relationship between circadian variations in blood pressure (BP) and albuminuria at rest, and during exercise in non-hypertensive type 2 diabetes (T2D) patients. METHODS: We conducted a cross-sectional study in well controlled T2D patients, non-hypertensive, without clinical proteinuria and normal creatinine clearance. In each participant, we recorded the BP using ambulatory blood pressure monitoring (ABPM) for 24-h, and albuminuria at rest and after a standardized treadmill exercise. RESULTS: We enrolled 27 type 2 patients with a median age of 52; and a mean duration of diabetes and HbA1c of 3.6 ± 0.8 years and 6.3% ± 0.5% respectively. Using a 24-h ABPM, we recorded a mean diurnal systolic blood pressure (SBP) of 128 ± 17 mmHg vs nocturnal of 123 ± 19 mmHg (P = 0.004), and mean diurnal diastolic blood pressure (DBP) of 83 ± 11 mmHg vs nocturnal 78 ± 14 mmHg (P = 0.002). There was a significant difference between albuminuria at rest [median = 23 mg, interquartile range (IQR) = 10-51] and after exercise (median = 35 mg, IQR = 23-80, P < 0.001). Patients with exercise induced albuminuria had an increase in nocturnal BP values on all three components (128 mmHg vs 110 mmHg, P = 0.03 for SBP; 83 mmHg vs 66 mmHg, P = 0.04; 106 vs 83, P = 0.02 for mean arterial pressure), as well as albuminuric patients at rest. Moreover, exercise induced albuminuria detect a less increase in nocturnal DBP (83 vs 86, P = 0.03) than resting albuminuria. CONCLUSION: Exercise induced albuminuria is associated with an increase in nocturnal BP values in T2D patients.

Blood Lead Levels among Children in Yaoundé Cameroon.

Blood lead levels (BLLs) are a useful indication of a population exposure to lead from environmental sources. No previous published study had reported BLLs in Cameroon. Our objective is to characterize exposure levels in children to inform policymakers of potential lead exposure sources. We tested the BLLs of 147 children aged 12 months to 6 years residing in Yaoundé, Cameroon, and conducted an extensive questionnaire with their parents or guardians to characterize potential exposure sources. The geometric mean BLL among this population was 8.0 µg/dl and arithmetic mean level was 8.7 µg/dl. These levels are more than sixfold higher than the geometric mean BLL reported in the U.S. and more than fivefold higher than those reported in France. In addition, 88% of the children tested had lead levels greater than 5 µg/dl. One limitation of the study is that the selection of the children sampled was not a random survey. The analysis of the responses to the questionnaire failed to uncover any specific exposure patterns. A statistically significant association was noted between the age of the child's home and the duration of exclusive breastfeeding with BLLs. The study points to a need for greater efforts to control sources of lead exposure in Cameroon.

The 22q11.2 Deletion Syndrome in Congenital Heart Defects: Prevalence of Microdeletion Syndrome in Cameroon.

BACKGROUND: The 22q11.2 deletion syndrome is amongst the most common microdeletion syndrome in humans. Its prevalence remains unknown in sub-Saharan Africa, and its clinical features are under-reported for people of African descent. OBJECTIVE: We have investigated the prevalence of the 22q11.2 deletion syndrome in patients with congenital heart defects in Cameroon. METHODS: A total of 70 of 100 cases of congenital cardiac malformation with echocardiographic evidence were examined prospectively and tested for the 22q11.2 deletion, using multiplex ligation-dependent probe amplification and fluorescence in situ hybridization. RESULTS: Two of 70 patients (2.8%) were found to have 22q11.2 deletion. Both cases had conotruncal heart defects and exhibited extracardiac features of the 22q11.2 deletion syndrome that were either classical (e.g., puffy upper eyelids, bulbous tip of the nose) or less identifiable (telecanthus, hooding of eyelids and prominent nasal bridge). CONCLUSIONS: The report shows that the prevalence of the 22q11.2 deletion syndrome in patients with heart malformations in Cameroon (2.8%) is similar to that of various world populations. The clinical phenotypes will contribute to the Global Atlas for dysmorphology. "Omics" technologies offer much promise in genetic/genomic screening of severe global health problems.

Surgery for rheumatic mitral valve disease in sub-saharan African countries: why valve repair is still the best surgical option.

Rheumatic valve disease, a consequence of acute rheumatic fever, remains endemic in developing countries in the sub-Saharan region where it is the leading cause of heart failure and cardiovascular death, involving predominantly a young population. The involvement of the mitral valve is pathognomonic and mitral surgery has become the lone therapeutic option for the majority of these patients. However, controversies exist on the choice between valve repair or prosthetic valve replacement. Although the advantages of mitral valve repair over prosthetic valve replacement in degenerative mitral disease are well established, this has not been the case for rheumatic lesions, where the use of prosthetic valves, specifically mechanical devices, even in poorly compliant populations remains very common. These patients deserve more accurate evaluation in the choice of the surgical strategy which strongly impacts the post-operative outcomes. This report discusses the factors supporting mitral repair surgery in rheumatic disease, according to the patients' characteristics and the effectiveness of the current repair techniques compared to prosthetic valve replacement in developing countries.

Verbal autopsy and therapeutic itinerary of children who die before arrival in a paediatric centre in Yaoundé, Cameroon.

BACKGROUND: In Cameroon the rate of infant-juvenile mortality remains high and most death occur in the community. Mortality statistics is usually based on hospital data which are generally insufficient and less reliable. In a context where legislation on death registration is not applied, and where conventional autopsy is not often done, verbal autopsy (VA) provides information on mortality. This study tried to experiment this method and also analyses the therapeutic pathway of a group of children who died before arrival at the emergency department of a pediatric hospital. METHODS: A cross sectional descriptive study was carried out on children who died before arrival, at the Mother and Child Centre of the Chantal Biya Foundation in Yaounde, between October 2013 and April 2014. The addresses of parents or relatives of the deceased children were registered at the start of the study. Each respondent was interviewed 5 to 6 weeks later at the residence of the deceased child, with the aid of a VA questionnaire. Information obtained was on the socio-demographic characteristics of the families, past history of deceased, clinical presentation and the different health care services sought before the death. RESULTS: In all, 40 children who died were included in the study. The majority of the deceased children were less than 5 years (82.5%) with 50.0% being less than 1 year of age. Almost half of them (47.5%) had been ill for more than 24 hours, 40% for more than 3 days. Up to 50.0% had not been taken to a health facility. Most of them had visited 2 or 3 other health facilities before dying on the way to our hospital. Auto medication was frequent (42.5%); parents initially recourse to drugs which were either bought or obtained from home. Some parents (25.0%) brought their children only after they had been to a private dispensary, or a traditional healer (15.0%). Only 7.5% benefited from consultation in a public health facility and 2.5% resorted to prayers and incantations. Whatever the kind of care sought, the choice was mostly guided by its proximity (32.5%), advice from a relative (27.5%) or its affordability. CONCLUSIONS: It is of crucial importance that the government reinforces the measures to avoid the existence of clandestine health centres and check the competence of health care professionals. Improving referral/counter referral system will permit the limitation of fatal medical errors.

Genetics of Sickle Cell-Associated Cardiovascular Disease: An Expert Review with Lessons Learned in Africa.

Sickle cell disease (SCD) vastly impacts the African continent and is associated with cardiovascular diseases. Stroke, kidney disease, and pulmonary hypertension are considered as proxies of severity in SCD with several genomic loci implicated in their heritability. The present expert review examined the current data on epidemiology and genetic risk factors of stroke, pulmonary hypertension, and kidney disease associated with SCD, as indexed in PubMed® and Google Scholar®. Studies collectively show that stroke and kidney disease each affect ∼10% of SCD patients, with pulmonary hypertension displaying a higher prevalence of 30% among adults with SCD. There is some evidence that these epidemiology figures may be an underestimate in SCD patients living in Africa. A modest number of publications have identified genetic factors involved in pathways regulating inflammation, coagulation, cell adhesion, heme degradation, α-globin and γ-globin production, and others, which contribute to the development risk of targeted cardiovascular phenotypes. However, in most cases, these studies have not been validated across populations. There is therefore an urgent need for large-scale genome-wide association, whole-exome and whole-genome studies, and multiomics research on cardiovascular diseases associated with SCD, particularly in Africa, to allow for proportional investment of global research funding on diseases that greatly impact the African continent. Ultimately, this will cultivate socially responsible research investments and identification of at-risk individuals with improved preventive medicine, which should be a cornerstone of global precision medicine.