A.T. Sidibé’s research while affiliated with University of Bamako and other places

What is this page?


This page lists works of an author who doesn't have a ResearchGate profile or hasn't added the works to their profile yet. It is automatically generated from public (personal) data to further our legitimate goal of comprehensive and accurate scientific recordkeeping. If you are this author and want this page removed, please let us know.

Publications (93)


HLA‐class II amino acid position associations. The −Log10 of the locus‐level p‐value of association is shown for each of 90 polymorphic DRB1, DQB1, and DQA1 amino acid positions with −Log10(p‐value) > 1.30103 (an unadjusted p‐value of 0.05). Values for DRB1 positions are represented by light‐blue squares, for DQA1 in yellow triangles, and for DQB1 in orange circles. For each locus, the −Log10 of the adjusted locus‐level threshold of significance (calculated as 0.05/the number of variant amino acids positions at each locus) is shown with a horizontal red bar. These values are 2.9542 for DRB1, 2.8808 for DQA1 and 2.9912 for DQB1 (for 45, 38, and 49 variant amino acid positions displaying significant individual association), respectively. For all loci, including HLA‐A, ‐B, ‐C, ‐DPA1, and ‐DPB1, the overall −Log10 threshold of significance for all variant amino acid positions (339) is shown with a horizontal green bar. This value is 3.8312. For each locus, the amino acid position corresponding to the indicated Position Number is as follows: Position Numbers 1–28 correspond to DRB1 Amino Acid Positions −25, −24, −17, −16, −1, 9, 11, 12, 13, 26, 28, 30, 31, 33, 37, 58, 67, 70, 71, 74, 96, 98, 104, 120, 133, 142, 149, and 180, respectively. Position Numbers 29–53 correspond to DQA1 Amino Acid Positions −16, −13, 11, 18, 26, 34, 45, 47, 48, 50, 52, 53, 55, 56, 61, 64, 66, 69, 76, 80, 129, 175, 207, 215, and 218, respectively. Position Numbers 54–90 correspond to DQB1 Amino Acid Positions −21, −10, −6, −4, 9, 13, 26, 28, 30, 37, 38, 45, 46, 47, 52, 53, 55, 56, 57, 66, 67, 70, 71, 74, 75, 77, 84, 85, 86, 87, 89, 90, 135, 167, 203, 220, and 221.
Complete HLA genotyping of type 1 diabetes patients and controls from Mali reveals both expected and novel disease associations
  • Article
  • Full-text available

December 2023

·

55 Reads

·

5 Citations

HLA

Janelle A. Noble

·

·

Assa Traore Sidibé

·

[...]

·

Steven J. Mack

HLA genotyping was performed on 99 type 1 diabetes (T1D) patients and 200 controls from Mali. Next‐generation sequencing of the classical HLA‐A, ‐B, ‐C, ‐DRB1, ‐DRB3, ‐DRB4, ‐DRB5, ‐DQA1, ‐DQB1, ‐DPA1, and ‐DPB1 loci revealed strong T1D association for all loci except HLA‐C and ‐DPA1. Class II association is stronger than class I association, with most observed associations predisposing or protective as expected based on previous studies. For example, HLA‐DRB1*03:01, HLA‐DRB1*09:01, and HLA‐DRB1*04:05 predispose for T1D, whereas HLA‐DRB1*15:03 is protective. HLA‐DPB1*04:02 (OR = 12.73, p = 2.92 × 10⁻⁰⁵) and HLA‐B*27:05 (OR = 21.36, p = 3.72 × 10⁻⁰⁵) appear highly predisposing, although previous studies involving multiple populations have reported HLA‐DPB1*04:02 as T1D‐protective and HLA‐B*27:05 as neutral. This result may reflect the linkage disequilibrium between alleles on the extended HLA‐A*24:02~HLA‐B*27:05~HLA‐C*02:02~HLA‐DRB1*04:05~HLA‐DRB4*01:03~HLA‐DQB1*02:02~HLA‐DQA1*02:01~HLA‐DPB1*04:02~HLA‐DPA1*01:03 haplotype in this population rather than an effect of either allele itself. Individual amino acid (AA) analyses are consistent with most T1D association attributable to HLA class II rather than class I in this data set. AA‐level analyses reveal previously undescribed differences of the HLA‐C locus from the HLA‐A and HLA‐B loci, with more polymorphic positions, spanning a larger portion of the gene. This may reflect additional mechanisms for HLA‐C to influence T1D risk, for example, through expression differences or through its role as the dominant ligand for killer cell immunoglobulin‐like receptors (KIR). Comparison of these data to those from larger studies and on other populations may facilitate T1D prediction and help elucidate elusive mechanisms of how HLA contributes to T1D risk and autoimmunity.

Download

Clinical features, biochemistry and HLA‐DRB1 status in youth‐onset type 1 diabetes in Mali

September 2022

·

34 Reads

·

7 Citations

Objective: Limited information is available regarding youth-onset diabetes in Mali. We investigated demographic, clinical, biochemical, and genetic features in new diabetes cases in children and adolescents. Research design and methods: The study was conducted at Hôpital du Mali in Bamako. A total of 132 recently-diagnosed cases <21 years were enrolled. Demographic characteristics, clinical information, biochemical parameters (blood glucose, HbA1c, C-peptide, glutamic acid decarboxylase-65 (GAD-65) and islet antigen-2 (IA2) autoantibodies) were assessed. DNA was genotyped for HLA-DRB1 using high-resolution genotyping technology. Results: A total of 130 cases were clinically diagnosed as type 1 diabetes (T1D), one with type 2 diabetes (T2D), and one with secondary diabetes. A total of 66 (50.8%) T1D cases were males and 64 (49.2%) females, with a mean age at diagnosis of 13.8 ± 4.4 years (range 0.8-20.7 years) peak onset of 15 years. 58 (44.6%) presented in diabetic ketoacidosis; with 28 (21.5%) IA2 positive, 76 (58.5%) GAD-65 positive, and 15 (11.5%) positive for both autoantibodies. HLA was also genotyped in 195 controls without diabetes. HLA-DRB1 genotyping of controls and 98 T1D cases revealed that DRB1*03:01, DRB1*04:05, and DRB1*09:01 alleles were predisposing for T1D (odds ratios [ORs]: 2.82, 14.76, and 3.48, p-values: 9.68E-5, 2.26E-10, and 8.36E-4, respectively), while DRB1*15:03 was protective (OR = 0.27; p-value = 1.73E-3). No significant differences were observed between T1D cases with and without GAD-65 and IA2 autoantibodies. Interestingly, mean C-peptide was 3.6 ± 2.7 ng/ml (1.2 ± 0.9 nmol/L) in T1D cases at diagnosis. Conclusions: C-peptide values were higher than expected in those diagnosed as T1D and autoantibody rates lower than in European populations. It is quite possible that some cases have an atypical form of T1D, ketosis-prone T2D, or youth-onset T2D. This study will help guide assessment and individual management of Malian diabetes cases, potentially enabling healthier outcomes.



Rapid increases in observed incidence and prevalence of Type 1 diabetes in children and youth in Mali, 2007‐2016

February 2021

·

41 Reads

·

26 Citations

Aims Determine incidence, prevalence and mortality of type 1 diabetes (T1D) in children and youth <25 years (y) in Mali during the first 10 years of the Santé Diabète/Life for a Child program. Methods Data were collected from the prospective program register. Diagnosis of T1D was clinical, based on presentation, clinical features, immediate requirement for insulin, and no suggestion of other diabetes types. Results 460 cases were diagnosed with T1D <25y in 2007‐2016. Male‐to‐female ratio was 1.04:1. Peak age at onset was 15‐16y (range 1.1‐24y). T1D incidence <25 years per 100,000 population/y increased from 0.12 in 2007 to 0.74 in 2016 (an 18% annualized increase, p<0.001). Incidence peaked at 0.80 in 2014, the year after an education campaign was conducted. Incidence <15y rose from 0.12 to 0.35 per 100,000/y in 2007 and 2016 respectively (14% annualized increase, p<0.001). There was a steep, consistent increase in prevalence (per 100,000) from 0.43 in 2007 to 2.90 in 2016 (p<0.001). Prevalence <15y was 0.34/100,000 in 2007 and 1.02/100,000 by 2016 (p<0.001). Overall crude mortality rate was 30.0/1,000 patient years, equating to a standardized mortality rate of 9.0, with vital status known for 99.8% of cases. Conclusions Known incidence and prevalence of diabetes in Mali increased rapidly from 2007 to 2016, contemporaneous with the introduction and development of the Santé Diabète/Life for a Child program. Improved diagnosis and care resulting in lower mortality are likely contributors. True incidence may still be underestimated, with some cases still dying undiagnosed and full study ascertainment being uncertain. This article is protected by copyright. All rights reserved.



Improving haemophilia diagnosis in developing countries: the Malian experience

June 2020

·

66 Reads

·

2 Citations

The Journal of Haemophilia Practice

Introduction Around 90% of all undiagnosed people with haemophilia (PWH) live in developing countries. In Mali, in sub-Saharan Africa, nearly 90% of potential PWH are not identified. We initiated a two-year study involving an integrated programme of training and awareness-raising with the aim of improving diagnosis and access to care for PWH, based on partnership with those who regularly interact with them. Methodology Our training programme focused on four regions of Mali and the district of Bamako, and included three types of health professionals from different districts and hospitals: medical doctor, nurse and laboratory technician. We also targeted traditional healers, who continue to be strongly involved in local healthcare, and provided training sessions for patients and their families on the symptoms, diagnosis, treatment and complications of haemophilia. A complementary programme of awareness-raising, including the national media, ran alongside the training sessions. Results Overall, the programme involved 495 participants: 213 health care professionals, 24 patients, 79 parents of patients, 126 traditional healers, and 53 media workers. A direct result was development of collaboration between these groups in identifying haemophilia, and the transfer of four patients from a traditional healer's office to hospital for diagnosis and treatment. The number of diagnosed PWH increased from 42 in 2016 to 126 in 2017. Conclusion The integrated haemophilia educational programme, which took into account the nature of the local environment and involved all relevant stakeholders, showed that taking a collaborative approach is a successful strategy for improving diagnosis and care for PWH in Mali. This approach could be relevant in other developing countries.






Citations (40)


... The genetic loci which modify an individual's risk of developing T1D have been well characterized [15]. Notably, of the genetic loci, the HLA region, particularly class II HLA, has the greatest impact on an individual's risk of developing T1D [16]. This genetic association provides further evidence for the role of CD4 + T cells in the autoimmune pathogenesis of T1D. ...

Reference:

Current and Emerging Assays for Measuring Human T-Cell Responses Against Beta-Cell Antigens in Type 1 Diabetes
Complete HLA genotyping of type 1 diabetes patients and controls from Mali reveals both expected and novel disease associations

HLA

... 11,21 Similar to European-origin populations, children and youth diagnosed with T1D in Mali generally have detectable islet autoantibodies, but atypical islet autoantibody-negative forms of diabetes are more common. 22 People with T1D need daily treatment with insulin to survive. The WHO Global Diabetes Compact, launched in 2021, is a global initiative to ensure that all people diagnosed with diabetes have access to equitable, comprehensive, affordable, and quality treatment and care. ...

Clinical features, biochemistry and HLA‐DRB1 status in youth‐onset type 1 diabetes in Mali
  • Citing Article
  • September 2022

... The male predominance was highlighted in our series with a sex ratio of 1.30. This result is identical to certain African series [3,6,7,9,13,14,15] ; other African series, on the other hand, show a female predominance [8,11,12,16,17] . It should be noted that there is no parallelism between the onset of diabetic foot and sex. ...

Problem Of Diabetic Foot Amputations
  • Citing Article
  • January 2019

Le Mali médical

... Additionally, many persons living with T2D were undiagnosed, and few reportedly received treatment 14,15 . T2D increases in Africa may be associated with factors such as urbanization, adaptative lifestyle behaviors (obesity, alterations in eating habits, and reduced physical activity), genetics 15 , hypertension, age demographics, and pregnancy rates 16,17 . A study in Kenya linked health-seeking behaviors in T2D subjects with treatment facility type, self-rated health status, alcohol use, hospital admission, and social support 18 . ...

Epidemiological And Clinical Survey Of The Diabetes Sweetens In A Center Of Health Of Reference Of Sikasso
  • Citing Article
  • January 2019

Le Mali médical

... The decrease in antioxidant capital in diabetics has been reported by other authors. The work of Sow DS. et al in a Malian population showed an increase in enzymatic defence systems with an increase in superoxide dismutase (SOD) (73.3%) [12]. Indeed, SOD is the first antioxidant fighting enzyme and its increase indicates oxidative stress and an antioxidant defence reaction [12]. ...

Status Of Markers Of Oxidative Stress At The Internal Medicine And Endocrinology Department Of The Mali Hospital
  • Citing Article
  • January 2019

Le Mali médical

... 7 Since 2007, the French non-government organization Santé Diabète, in close partnership with the Malian Ministry of Health, has been providing a diabetes care program to all children and youth with T1D in the country. 11 This has been supported since 2008 by the Life for a Child program (LFAC), 12 which provides diabetes supplies including insulin, blood glucose monitoring supplies, education, mentoring, and technical support. Insulin and diabetes supplies to youth with T1D in Mali are not routinely available outside of this program. ...

Rapid increases in observed incidence and prevalence of Type 1 diabetes in children and youth in Mali, 2007–2016
  • Citing Article
  • September 2021

Yearbook of Paediatric Endocrinology

... Estimativas indicam que a prevalência da diabetes diagnosticada e não diagnosticada foi de 9,3% (463 milhões de pessoas) em 2019, com projeções de aumento para 10,2% (578 milhões) até 2030 e 10,9% (700 milhões) até 2045(Bak et al., 2021). Esse aumento está diretamente ligado ao envelhecimento da população e à adoção de estilos de vida pouco saudáveis, que resultam em uma maior prevalência de obesidade(Aschner et al., 2021).A respeito da epidemiologia do DM1, estima-se que 108.200 crianças menores de 15 anos desenvolvem DM1 em todo o mundo anualmente, com este número aumentando para quase 149.500 menores de 20 anos(Sandy et al., 2021). Há uma estimativa de que 600.900 crianças menores de 15 anos vivam com diabetes tipo 1 em todo o mundo, com este número quase dobrando para 1.110.100 ...

Rapid increases in observed incidence and prevalence of Type 1 diabetes in children and youth in Mali, 2007‐2016
  • Citing Article
  • February 2021

... There is therefore a need for concerted efforts to ensure access Processes and experiences of satellite haemophilia clinic set-ups in Ugandaa short report to care services by affected persons. Initiatives organised by the World Federation of Hemophilia are helping this [2] , as is the work of its national member organisations [5] . ...

Improving haemophilia diagnosis in developing countries: the Malian experience

The Journal of Haemophilia Practice

... Our study included volunteers who were 16 years of age or older who had type 1 or type 2 diabetes and who were able to understand and answer questions in French (the official language of the country) or in Bambara (the national language of the country) and who complied with a follow-up visit at the GT-UHC and/or the CCD. The sample size was estimated to be 252 using Kish's formula (n = Z 2 � (P � Q)/i 2 ) [27], with an estimated prevalence of diabetic polyneuropathy in Mali of 50% [28,29], a 95% confidence interval yielding Z = 1.96, and accuracy i = 9%. The sampling was systematic based on the order of arrival of eligible patients at one of the two facilities, but randomized, i.e., only every fourth eligible patient was recruited. ...

Podological risk in patients suffering with diabetes in a Bamako health center
  • Citing Article
  • January 2014

Le Mali médical