# Persistence of L. V. braziliensis in the Nasal Mucosa of Treated Patients

## TL;DR

This study shows that L. V. braziliensis DNA can persist in the nasal mucosa of treated leishmaniasis patients, indicating a risk of future mucosal disease.

## Contribution

The study introduces nasal mucosa DNA testing as a novel method to assess long-term risk of mucosal leishmaniasis.

## Key findings

- 7% of treated patients tested positive for L. V. braziliensis DNA in nasal mucosa.
- 60% of these positive patients had mucosal lesions before treatment, compared to 13.4% of negatives (p = 0.031).
- Molecular detection in nasal mucosa could improve follow-up for leishmaniasis patients.

## Abstract

Background/Objectives: Cutaneous leishmaniasis is an infectious disease that most frequently affects neglected populations. Besides its incidence, a high disease burden is associated with the possibility of mucosal sequelae. Clinical follow-up of these patients is difficult due to the limited access of the affected population to healthcare and the long lapse between the development of cutaneous and mucosal diseases. In this study, we evaluated the positivity of L. V. braziliensis DNA on the nasal mucosa of patients treated for leishmaniasis in an attempt to estimate the possible long-term risk of developing mucosal leishmaniasis and its association with important clinical characteristics. Methods: Samples were collected immediately after treatment completion using a nasal swab and specific DNA was amplified and detected using real-time PCR. Clinical and laboratorial data was systematically collected. Results: The positivity of L. V. braziliensis was 7% after treatment, and of this 60% had mucosal lesions before treatment, compared with only 13.4% in patients negative for L. V. braziliensis after treatment (p = 0.031). Conclusions: Molecular detection of L. V. braziliensis DNA on the nasal mucosa is a promising strategy to improve the follow-up and treatment of patients with American Tegumentary Leishmaniasis.