Differences in Bacterial Colonization and Mucosal Responses Between High and Low SES Children in Indonesia.

BACKGROUND: Increased nasopharyngeal carriage of pathogenic bacteria is found in low socioeconomic status (SES) settings. How SES affects local immune responses, important for controlling colonization, is currently unknown. OBJECTIVE: Examining bacterial colonization and cytokine response in the nasal mucosa of children from high and low SES. METHODS: Nasosorption samples were collected in October 2019 from 48 high SES and 50 low SES schoolchildren, in a cross-sectional study in Makassar, Indonesia. Twenty-five cytokines were measured in nasal fluid. Quantitative polymerase chain reaction was performed to determine carriage and density of Haemophilus influenzae, Streptococcus pneumoniae, Moraxella catarrhalis and Staphylococcus aureus. Data were analyzed using multivariate regression. RESULTS: H. influenzae and S. pneumoniae densities were increased in low SES settings compared to the high SES settings (P = 0.006, P = 0.026), with 6 and 67 times higher median densities, respectively. Densities of H. influenzae and S. pneumoniae were positively associated with levels of IL-1beta and IL-6. After correcting for bacterial density, IL-6 levels were higher in colonized children from high SES than low SES for H. influenzae and S. pneumoniae (both P = 0.039). CONCLUSION: Increased densities of H. influenzae and S. pneumoniae were observed in low SES children, whereas IL-6 levels associated with colonization were reduced in these children, indicating that immune responses to bacterial colonization were altered by SES.

Intestinal permeability before and after albendazole treatment in low and high socioeconomic status schoolchildren in Makassar, Indonesia.

Intestinal helminths are highly prevalent in low-SES children and could contribute to poor health outcomes either directly or via alteration of the gut microbiome and gut barrier function. We analysed parasitic infections and gut microbiota composition in 325 children attending high- and low-SES schools in Makassar, Indonesia before and after albendazole treatment. Lactulose/Mannitol Ratio (LMR, a marker of gut permeability); I-FABP (a surrogate marker of intestinal damage) as well as inflammatory markers (LBP) were measured. Helminth infections were highly prevalent (65.6%) in low-SES children. LMR and I-FABP levels were higher in low-SES children (geomean (95%CI): 4.03 (3.67-4.42) vs. 3.22 (2.91-3.57); p. adj < 0.001; and 1.57 (1.42-1.74) vs. 1.25 (1.13-1.38); p. adj = 0.02, respectively) while LBP levels were lower compared to the high-SES (19.39 (17.09-22.01) vs. 22.74 (20.07-26.12); p.adj = 0.01). Albendazole reduced helminth infections in low-SES and also decreased LMR with 11% reduction but only in helminth-uninfected children (estimated treatment effect: 0.89; p.adj = 0.01). Following treatment, I-FABP decreased in high- (0.91, p.adj < 0.001) but increased (1.12, p.adj = 0.004) in low-SES children. Albendazole did not alter the levels of LBP. Microbiota analysis showed no contribution from specific bacterial-taxa to the changes observed. Intestinal permeability and epithelial damage are higher while peripheral blood inflammatory marker is lower in children of low-SES in Indonesia. Furthermore, treatment decreased LMR in helminth-uninfected only.

Bee- and Wasp-Venom Sensitization in Schoolchildren of High- and Low-Socioeconomic Status Living in an Urban Area of Indonesia.

BACKGROUND: There is not much known about venom allergy in tropical regions. Here, we studied the prevalence of specific IgE (sIgE) and skin prick test (SPT) reactivity and reported sting-related symptoms, in high- and low-socioeconomic status (SES) schoolchildren living in urban city of Makassar in Indonesia. METHODS: Children from high- (n = 160) and low- (n = 165) SES schools were recruited. Standardized questionnaires were used to record information on allergic disorders as well as sting-related symptoms. Parasitic infection, SPT reactivity, and sIgE to Apis mellifera (bee-venom) as well as Vespula spp. (wasp-venom) were assessed. RESULTS: SPT reactivity to bee- and wasp-venom was 14.3 and 12.7%, while the prevalence of sIgE was 26.5 and 28.5%, respectively. When SES was considered, prevalence of SPT to bee- and wasp-venom was higher in high-SES than in low-SES schoolchildren (bee: 22.8 vs. 5.7%, p < 0.001; and wasp: 19.6 vs. 5.7%, p < 0.001). Conversely, sIgE to both venoms was lower in high-SES than in low-SES (bee: 19 vs. 34%, p = 0.016; and wasp: 19 vs. 38%, p = 0.003). Furthermore, among SPT positive subjects, considerable proportion had no detectable sIgE to bee- (65.85%) or wasp-venom (66.67%). Altogether the sensitizations were rarely translated into clinical reaction, as only 1 child reported significant local reaction after being stung. No association with parasitic infections was found. CONCLUSIONS AND CLINICAL RELEVANCE: Sensitization against bee- or wasp-venom is quite prevalent among schoolchildren in Indonesia. The discordance between SPT and sIgE might suggest the direct (non-IgE) effect of venoms in skin reactivity. Recorded sensitizations had poor clinical relevance as they rarely translated into clinical symptoms.

The relationship between malnutrition and TH 2 immune markers: a study in school-aged children of different socio-economic backgrounds in Makassar, Indonesia.

OBJECTIVE: The burden of underweight remains a major problem in Indonesia, and at the same time, the prevalence of overweight is increasing. Malnutrition is a major determinant of health and has been linked to allergic disorders in children. We examined the relationship between malnutrition and TH 2 immune markers in school-aged children in Makassar, Indonesia. METHODS: A cross-sectional study was performed in five schools where socio-demographic characteristics were recorded. Children's standardised z-scores of body mass index (z-BMI) and age-standardised z-scores of height (z-HA) were assessed using WHO child growth standards. Skin prick test (SPT) reactivity was determined to house dust mite allergens. Helminth infection status, (growth) hormones including insulin-like growth factor (IGF-1) and TH 2 immune markers were measured. RESULTS: In total, 954 children were included of whom 21.6% were underweight and 14.8% overweight. After controlling for confounders, overweight was positively associated with leptin (GMR 3.55, 95% CI: 2.99-4.23) and IGF-1 (GMR 1.45, 95% CI: 1.15-1.82), whereas underweight was negatively associated (respectively GMR 0.57, 95% CI: 0.49-0.66 and GMR 0.78, 95% CI: 0.63-0.97). Underweight was associated with a lower eosinophil count (GMR 0.79, 95% CI: 0.64-0.97) but not with total IgE levels or SPT reactivity. Overweight was positively associated with SPT reactivity (adjusted OR 2.68, 95% CI: 1.50-4.78) but no relationship was found with the other TH 2 immune markers. CONCLUSION: Malnutrition is prominent in school-aged children in Makassar, with overweight associated with increased SPT reactivity. Therefore, interventions should focus on undernutrition, but also on overweight to prevent the increase of allergic disorders in Indonesia.

OBJECTIF: La charge de l'insuffisance pondérale reste un problème majeur en Indonésie et parallèlement, la prévalence du surpoids augmente. La malnutrition est un déterminant majeur de la santé et a été associée à des troubles allergiques chez les enfants. Nous avons examiné la relation entre la malnutrition et les marqueurs immunitaires TH 2 chez les enfants d'âge scolaire à Makassar, en Indonésie. MÉTHODES: Etude transversale dans cinq écoles où les caractéristiques sociodémographiques ont été enregistrées. Les scores z standardisés de l'indice de masse corporelle (z-IMC) et les scores z standardisés pour l'âge de la taille (z-HA) pour les enfants ont été évalués en utilisant les normes de croissance de l'enfant de l'OMS. La réactivité du test cutané (SPT) a été déterminée pour les allergènes d'acariens. L'état de l'infection par les helminthes, les hormones (de croissance), y compris le facteur de croissance analogue à l'insuline (IGF-1) et les marqueurs immunitaires TH 2 ont été mesurés. RÉSULTATS: Au total, 954 enfants ont été inclus, dont 21,6% en insuffisance pondérale et 14,8% en surpoids. Après contrôle des facteurs de confusion, le surpoids était positivement associé à la leptine (GMR 3,55, IC95%: 2,99-4,23) et à l'IGF-1 (GMR 1,45 ; IC95%: 1,15-1,82), tandis que l'insuffisance pondérale était associée négativement (respectivement GMR 0,57 ; IC95%: 0,49-0,66 et GMR 0,78 ; IC95%: 0,63-0,97). L'insuffisance pondérale était associée à un nombre plus faible d'éosinophiles (GMR 0,79 ; IC95%: 0,64-0,97) mais pas aux taux d'IgE totaux ou à la réactivité du SPT. Le surpoids était positivement associé à la réactivité du SPT (OR ajusté 2,68 ; IC95%: 1,50-4,78) mais aucune relation n'a été trouvée avec les autres marqueurs immunitaires T H 2. CONCLUSION: La malnutrition est importante chez les enfants d'âge scolaire à Makassar, avec un surpoids associé à une réactivité accrue du SPT. Par conséquent, les interventions devraient se concentrer sur la dénutrition, mais aussi sur le surpoids pour prévenir l'augmentation des troubles allergiques en Indonésie.

The Bacterial Gut Microbiota of Schoolchildren from High and Low Socioeconomic Status: A Study in an Urban Area of Makassar, Indonesia.

To understand the relationship between the gut microbiota and the health profile of Indonesians, it is important to elucidate the characteristics of the bacterial communities that prevail in this population. To this end, we profiled the faecal bacterial community of 140 Indonesian schoolchildren in urban Makassar. The core microbiota of Indonesian schoolchildren consisted of Bifidobacterium, Collinsella, and multiple members of the Lachnospiraceae and Ruminicoccaceae families, but the relative abundance of these taxa varied greatly among children. Socioeconomic status (SES) was the main driver for differences in microbiota composition. Multiple bacterial genera were differentially abundant between high and low SES children, including Bifidobacterium, Lactobacillus, Prevotella, and Escherichia-Shigella. In addition, the microbiota of high SES children was less diverse and strongly associated with body mass index (BMI). In low SES children, helminth infection was prevalent and positively associated with Olsenella, Enterohabdus, Lactobacillus, and Mogibacterium abundance, while negatively associated with relative abundance of Prevotella. Protozoa infection was also prevalent, and positively associated with Rikenellaceae, while it was negatively associated with the relative abundance of Romboutsia and Prevotella. In conclusion, Indonesian schoolchildren living in urban Makassar share a core microbiota, but their microbiota varies in diversity and relative abundance of specific bacterial taxa depending on socioeconomic status, nutritional status, and intestinal parasites infection.