IL8 and IL17A polymorphisms associated with multibacillary leprosy and reaction type 1 in a mixed population from southern Brazil

Characterization of cases and epidemiological and operational indicators of leprosy: analysis of time series and spatial distribution, Piauí state, Brazil, 2007-2021

OBJECTIVE

To analyze epidemiological characteristics, temporal trends and spatial distribution of leprosy cases and indicators in the state of Piauí, 2007-2021.

METHODS

This was an ecological time-series study using data from the Notifiable Health Conditions Information System, describing the spatial distribution and the temporal trend of leprosy using Prais-Winsten regression.

RESULTS

A total of 17,075 new cases of leprosy were reported. There was a falling trend in the overall detection rate [annual percentage change (APC) = -6.3; 95%CI -8.1;-4.5)], detection in children under 15 years of age (APC = -8,6; 95%CI -12,7;-4,3) and detection of cases with grade 2 physical disability (APC = -4,4; 95%CI -7,0;-1,8). There was a rising trend in the proportion of multibacillary cases. Spatial distribution of the average detection rate identified hyperendemic areas in the Carnaubais, Entre Rios, Vale dos Rios Piauí e Itaueiras regions.

CONCLUSION

High leprosy detection rates were found, despite the falling trend of indicators, except the proportion of multibacillary cases.

MAIN RESULTS

Between 2007 and 2021, Piauí showed an improving trend in all indicators analyzed, except the proportion of new multibacillary cases. Spatial distribution identified hyperendemic areas in different regions of the state.

IMPLICATIONS FOR SERVICES

This study provides health services with a broad overview of the epidemiological situation of leprosy in Piauí, with evidence of the populations and locations most affected by the disease, whereby public authorities need to reinforce the promotion of health actions.

PERSPECTIVES

It is expected that actions to prevent and control the disease will be adopted, such as offering early diagnosis, ensuring correct treatment and implementing measures to prevent physical disabilities.

Interleukin-17A in Egyptian leprosy patients: A clinical, genetic, and biochemical study

Background

Leprosy represents a long-term communicable disease resulting from Mycobacterium leprae infection. IL-17A is one of the pro-inflammatory cytokines that protects humans against many fungal and bacterial pathogens.

Objective

To investigate IL-17A (rs2275913) gene polymorphism and its circulating level in leprosy patients, and to correlate the detected results with different clinical aspects of leprosy in the investigated patients.

Methods

60 patients with leprosy, and 29 age and sex-matched volunteers were investigated for IL-17A serum level and IL-17A single nucleotide polymorphism (SNP) by ELISA and RFLP-PCR respectively.

Results

IL-17A serum level was significantly higher in leprosy patients than in controls (p = 0.034), and in TL than LL (p = 0.017). IL-17A (rs2275913 A/G) G allele and GG genotype were associated significantly with LL (p = 0.005and 0.001 respectively). IL-17A (rs2275913 A/G) AG genotype carriers demonstrated the highest IL-17A serum levels; however, its lowest levels were found in IL-17A (rs2275913 A/G) AA genotype carriers (p = 0.005). Grade 2 disability (p = 0.030) and positive slit skin smear (SSS) (p = 0.005) were significantly associated with IL-17A (rs2275913 A/G) GG genotype.

Study limitations

The small number of studied subjects.

Conclusions

IL -17A may have a pivotal role in leprosy pathogenesis. IL-17A (rs2275913) GG genotype plus G allele might be related to the development of LL in the Egyptian population.

Serum IL-6 level and nutrition status as potential predictors of clinical leprosy development among household contacts in the endemic areas

Background

Leprosy is a chronic infectious disease that can lead to severe life-long disabilities. Close contacts of leprosy patients have a higher risk of acquiring the disease. Nevertheless, there is a lack of reliable markers to predict Mycobacterium leprae infection. We aim to identify new potential markers for developing clinical leprosy among contacts.

Methods

Serum levels of IL-6, IL-8, IL-10, hemoglobin, ferritin and transferrin saturation were measured in 67 multibacillary leprosy (MB) patients, 65 household contacts (HC) of MB patients, and 127 endemic controls (EC). By means of multivariate logistic regression and ROC analyses, we analyze baseline variables and laboratory parameters that showed significant differences between MB with HC and EC groups and obtained the respective areas under the curve (AUC). Optimal cut-off value of the associated cytokines was also determined.

Results

Elevated IL-6 level was observed in MB compared to HC and EC (p=0.022 and 0.0041, respectively). Anemia and iron deficiency were also higher in MB group compared to HC or EC (p<0.001). Likewise, we observed an increased risk of having MB leprosy in underweight HC [OR 2.599 (0.991; 6.820)] and underweight EC [2.176 (1.010; 4.692)]. Further analysis with ROC showed that high serum IL-6 level, underweight, anemia, and iron deficiency can discriminate leprosy from their household contacts [AUC 0.843 (95% CI 0.771-0.914); p=0.000; optimal cut-off value of IL-6 = 9.14 pg/ml].

Conclusions

Our results suggest that serum IL-6 and nutrition status could serve as potential prognostic markers for the development of clinical leprosy in infected individuals.