Caracterização das lesões orais e da resposta imunológica local durante infecção aguda por Chikungunya Vírus

Abstract

Introduction: Chikungunya is a disease caused by the Chikungunya alphavirus (CHIKV), transmitted by Aedes aegypti and Aedes albopictus. In addition to fever and arthritis, Chikungunya disease (CHIKD) can lead to the appearance of oral lesions. Objective: To characterize oral lesions in acute CHIKV infection, relating them to the presence of the virus and the immune response in saliva. Methodology: Cross-sectional study with 228 patients recruited in the cities of Campo Formoso, Itabuna, Senhor do Bonfim and Maranguape (Ceará) between March 2016 and June 2017. Patients with suspected acute arbovirus infection underwent clinical evaluation by an otorhinolaryngologist and dentist, and completed a questionnaire containing signs and symptoms of the disease, including data on oral lesions. The diagnosis of CHIKV infection was confirmed by positive PCR in urine, blood and/or saliva samples or the presence of specific serum IgM. Additionally, the expression of chemokines and cytokines IL-1β, IL-6, TNFa, CCL2 and CXCL10 in saliva samples was determined by RT-qPCR. The distribution of variables was tested using the Kolmogorov Smirnov test and the nonparametric tests, in relation to the outcome, were the chi-square, Fisher's exact test and Mann Whitney test. Results: Of the 204 patients evaluated, 105 were diagnosed exclusively with CHIKD and had disease duration of less than 10 days at the time of evaluation. Oral lesions were detected in 36 (34%) cases, being more frequent in women (OR = 3.2). In most patients, the lesions were painful (n = 23, 72%) causing difficulty in feeding (n = 19, 59%). The main affected sites were the tongue (n=14, 44%), gums (n=14, 44%) and lips (n=12, 37.5%) but they were also found in the buccal mucosa (n=7, 22%). The mucosal lesions presented as rounded ulcers with circumscribed margins and halo-erythematous (n=12, 37.5%) or edematous-erythematous regions in the marginal gingiva (n=2, 3%). Patients with CHIKD who presented oral lesions more frequently exhibited systemic symptoms of rash, pruritus, myalgia, edema and retroocular pain (p<0.05). In an ordinal logistic regression analysis, there was an association between the presence of oral lesions and skin rash (OR=7.817 p<0.05). CHIKV was detected in the saliva of 13% of the individuals evaluated. There was a positive correlation between the presence of viral RNA and the expression of IL-1β in saliva (p=0.01), but there was no association between the presence of oral lesions and detectable virus in saliva. Conclusions: Oral lesions are frequent in the acute phase of CHIKD, especially in patients with more exuberant clinical presentation, and contribute to the morbidity of the disease. The appearance of the lesion is not related to the presence of the virus or the secretion of inflammatory mediators in saliva, but the virus in saliva appears to induce a pro-inflammatory response in the oral cavity.