Epidemiology and management of asthma and atopic dermatitis in Sub-Saharan Africa

Lupus and other autoimmune diseases: Epidemiology in the population of African ancestry and diagnostic and management challenges in Africa

Autoimmune diseases are prevalent among people of African ancestry living outside Africa. However, the burden of autoimmune diseases in Africa is not well understood. This article provides a global overview of the current burden of autoimmune diseases in individuals of African descent. It also discusses the major factors contributing to autoimmune diseases in this population group, as well as the challenges involved in diagnosing and managing autoimmune diseases in Africa.

Understanding the Risk Factors, Burden, and Interventions for Chronic Respiratory Diseases in Low- and Middle-Income Countries: A Scoping Review

Objective

This scoping review aims to identify risk factors for COPD and asthma, examine the burden and intervention measures, and clarify the findings in the context of climate change, with a particular focus on LMICs.

Methods

Following the PRISMA-ScR guidelines, we conducted a scoping review using PubMed, Embase, and Scopus, focusing on studies published from 2011 to 2024.

Results

Our review included 52 studies that encompassed 244,004 participants. Predominantly conducted in SSA (n = 43, 83%) and Asia (n = 16, 31%), they address indoor and ambient air pollution, occupational hazards, and environmental conditions. Climate change exacerbates risks, varying regionally. SSA faces severe household and occupational exposures, while other LMICs deal with industrial and urban pollution. Stigma, social exclusion and economic burden underscore the necessity for intervention strategies (e.g., educational programs, pulmonary rehabilitation, low-emission cookstoves).

Conclusion

Our research shows a strong link between air pollution, occupational and environmental exposures, and the prevalence of COPD and asthma in LMICs. It suggests that targeted interventions are effective ways to mitigate these diseases and also highlights the significant impact of climate change on respiratory health.

Global, Regional and National Burden of Paediatric Atopic Dermatitis: A Trend and Geographic Inequalities Analysis

BACKGROUND

Atopic dermatitis (AD) is a common chronic skin disorder in children. We aimed to investigate trends and regional disparities of burden in paediatric AD at global, regional and national levels, and to explore potential associated factors.

METHODS

Based on data from Global Burden of Disease study 2019, we assessed trends in burden of AD aged <19 years from 1990 to 2019, including prevalent and incident cases, age-standardised prevalence and age-standardised incidence. For potential associated factors, correlations of above trends and indexes of socio-economic status (sociodemographic index, SDI) and health service coverage (universal health coverage index, UHCI) were evaluated. We conducted decomposition analysis to understand the net contribution of population-level factors and their contribution proportions on changes of prevalent and incident cases, including age structure, population change and epidemiological change.

RESULTS

Global prevalent and incident cases of paediatric AD increased by about 5.7 and 0.7 million between 1990 and 2019, respectively. Global age-standardised prevalence and incidence decreased by -0.17% (-0.19% to -0.16%) and -0.12% (-0.13% to -0.11%) per year from 1990 to 2019, respectively. Regionally, the highest increase of prevalent and incident cases was in low SDI region (by 96.77% and 84.85%); the highest decrease of age-standardised prevalence and incidence was in high SDI regions (by -0.20% and -0.27% per year). The correlation analyses identified significant negative correlations between trends and SDI and UHCI. Population change was a major driver of case rise; epidemiological change and age structure showed negative impact of case rise. Regional disparities in contribution of three population-level factors were seen, including net contribution direction (positive or negative) and contribution proportion levels.

CONCLUSION

Global paediatric AD case numbers increased, primarily due to population growth. Prevalence and incidence decreased slightly. Geographic inequalities were seen. Developing region-specific strategies targeting potential factors is essential to reduce paediatric AD burden.

Genetic and Immunological Pathogenesis of Atopic Dermatitis

Type 2 immune-mediated diseases give a clear answer to the issue of nature (genetics) versus nurture (environment). Both genetics and environment play vital complementary roles in the development of atopic dermatitis (AD). As a key component of the atopic march, AD demonstrates the interactive nature of genetic and environmental contributions to atopy. From sequence variants in the epithelial barrier gene encoding FLG to the hygiene hypothesis, AD combines a broad array of contributions into a single syndrome. This review will focus on the genetic contribution to AD and where genetics facilitates the elicitation or enhancement of AD pathogenesis.

Examining allergy related diseases in Africa: A scoping review protocol

During recent decades, allergy related diseases have emerged as a growing area of concern in developing regions of the world, including Africa. Worldwide prevalence of allergic diseases has grown to an estimated 262 million for asthma, 400 million for allergic rhinitis (or hay fever), 171 million with atopic dermatitis (or eczema), and over 200 million for food allergy. In Africa, considerable variability exists in the data surrounding prevalence at the continent-wide, regional, and study site levels. Furthermore, research conducted in many rural areas and underdeveloped countries in Africa remains limited, and presently, little has been done to characterize and map the extremely heterogeneous body of literature which confounds research efforts. This scoping review will seek to identify studies examining the prevalence, management strategies, outcomes, and associated risk factors for allergy related diseases in Africa. The Joanna Briggs Institute's scoping review methods will be followed, and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Review (PRISMA-ScR) was used for writing the protocol. Four databases (Embase, Global Health, PubMed, African Journals Online) will be searched for literature published from 2003 to 2023 in any language. Title and abstract screening and full-text screening will be completed by two independent reviewers using Covidence; conflicts resolved by a third reviewer. Data will be extracted using Covidence by two reviewers independently. To report the results, we will follow the PRISMA-ScR checklist and report descriptive statistics and a narrative summary.

Prevalence and Socioeconomic Impact of Allergic Rhinitis Among Ear, Nose, and Throat Patients of a Tertiary Hospital

OBJECTIVES

The objectives of this study were to establish the demographic factors of allergic rhinitis patients taking part in the study, to gain insight into the common symptoms experienced by patients with allergic rhinitis, to know the common allergens or triggers that lead to the symptoms of allergic rhinitis and to determine the prevalence of other comorbidities associated with allergic rhinitis.

METHODS

The study was a cross-sectional hospital-based study encompassing both quantitative and qualitative features of the participants involved. The quantitative study involved collecting data on allergic rhinitis clients visiting our tertiary hospital, over the period of March 1, 2021, to June 25, 2021. The quantitative data included the gender and age groups commonly affected, the most common symptom, and the trigger identified. Whilst, the qualitative aspect of the study involved the socioeconomic impact of allergic rhinitis on the clients.

RESULTS

The prevalence of allergic rhinitis is 10% at the ENT clinic of our hospital. It was most common in the age group (19-35). Urban residents suffered more from allergic rhinitis than the rural residents. The main presenting complaint was sneezing and the commonest comorbid condition and trigger associated with allergic rhinitis were sinusitis and dust mites respectively. Twenty-nine percent of respondents had experienced reduced productivity at their workplace and in school. Twenty-one percent had experienced depression while 26% perceived the cost of treatment to be greatly expensive. The use of face masks was found not to be beneficial in reducing the symptoms of allergic rhinitis in most clients.

CONCLUSION

The conclusions reached at the end of this study were that the public must be educated on allergic rhinitis and to look out for the triggers, signs, and symptoms of it and then report early to the hospital for appropriate management.

Frequent IgE recognition of Blomia tropicalis allergen molecules in asthmatic children and young adults in equatorial Africa

Background

Asthma is not well investigated in equatorial Africa and little is known about the disease-associated allergen molecules recognized by IgE from patients in this area. The aim was to study the molecular IgE sensitization profile of asthmatic children and young adults in a semi-rural area (Lambaréné) of an equatorial African country (Gabon), to identify the most important allergen molecules associated with allergic asthma in equatorial Africa.

Methods

Fifty-nine asthmatic patients, mainly children and few young adults, were studied by skin prick testing to Dermatophagoides pteronyssinus (Der p), D. farinae (Der f), cat, dog, cockroach, grass, Alternaria and peanut. Sera were obtained from a subset of 35 patients, 32 with positive and 3 with negative skin reaction to Der p and tested for IgE reactivity to 176 allergen molecules from different allergen sources by ImmunoCAP ISAC microarray technology and to seven recombinant Blomia tropicalis (Blo t) allergens by IgE dot blot assay.

Results

Thirty-three of the 59 patients (56%) were sensitized to Der p and 23 of them (39%) were also sensitized to other allergen sources, whereas 9 patients (15%) were only sensitized to allergen sources other than Der p. IgE serology analyses (n=35) showed high IgE-binding frequencies to the Blo t allergens Blo t 5 (43%), Blo t 21 (43%) and Blo t 2 (40%), whereas the Der p allergens rDer p 2, rDer p 21 and rDer p 5 (34%, 29% and 26%) were less frequently recognized. Only few patients showed IgE reactivity to allergens from other allergen sources, except to allergens containing carbohydrate determinants (CCDs) or to wasp venom allergens (i.e., antigen 5).

Conclusion

Our results thus demonstrate that IgE sensitization to mite allergens is very prevalent in asthmatics in Equatorial Africa with B. tropicalis allergen molecules representing the most important ones associated with allergic asthma.

Novel insights into atopic dermatitis

Recent research into the pathophysiology and treatment of atopic dermatitis (AD) has shown notable progress. An increasing number of aspects of the immune system are being implicated in AD, including the epithelial barrier, TH2 cytokines, and mast cells. Major advances in therapeutics were made in biologic cytokine and receptor antagonists and among Janus kinase inhibitors. We focus on these areas and address new insights into AD epidemiology, biomarkers, endotypes, prevention, and comorbidities. Going forward, we expect future mechanistic insights and therapeutic advances to broaden physicians' ability to diagnose and manage AD patients, and perhaps to find a cure for this chronic condition.