A sensibilidade em cavidade oral e orofaríngea e pesquisa do Mycobacterium leprae na saliva de pacientes com Hanseníase

Abstract

Leprosy is a chronic infectious disease caused by Mycobacterium leprae, which affects mainly the skin, peripheral nerves and mucous membranes. It is known that the Hansen bacillus has a predilection for Schwann cells that surround the axons of peripheral nerves, causing sensory loss as the location of the affected nerve. Among the most affected cranial nerves in subjects with leprosy are the trigeminal nerve, responsible for motor function of the masticatory muscles and the tactile, thermal and pain of the face, mucosa of the nasopharynx, hard and soft palate, as well as the 2 / 3 previous tongue, and facial nerve, which is responsible for the taste sensitivity of the anterior 2 / 3 of the tongue and movement of the facial muscles. In the present study, we investigated sensorimotor disorders in the oral cavity and oropharynx as well as the presence of Mycobacterium leprae in saliva from patients with leprosy attending in a Reference Center of Tropical Dermatology in Amazonas State from July to October 2010. We conducted a cross sectional study of case detection, with 45 subjects with leprosy and 45 subjects with other skin diseases as a control group. Subjects with leprosy were submitted to anamnesis, evaluation of the sensitivity of the oral cavity and oropharynx, ENT examination (clinical examination, nasal endoscopy and laryngoscopy), videofluoroscopy, and, molecular procedures – Real Time Polymerase Chain Reaction (qPCR) - and bacteriological to investigate the presence of DNA of M. leprae in saliva. The control group subjects were assessmented of oral sensitivity. The results were analyzed using descriptive and non-parametric statistics, noting that 15/45 (33.3%) of subjects with leprosy showed abnormalities in the oral sensitivity, and this data is statistically significant (p=0,002)when compared with the control group. In search of M leprae DNA in saliva, using the technique of Real-Time PCR, we detected 16 (35.5%) tested positive results of 45 subjects with leprosy. No direct relationship was observed between the presence of M. leprae in saliva and oral changes in sensitivity, but the positivity of the Real Time PCR in saliva (PCR in saliva) in six (31.6%) of 19 paucibacillary (PB) patients suggests the possibility of a new site of sample collection. The sum of the techniques for diagnosis (Slit-skin smear, PCR in saliva and PCR Slit-skin smear) increases the positive results to 55.55%. This is particulary important in difficult diagnosis cases, like paucibacillary patients.