Estudo da concentração salivar do fator de crescimento epidérmico em indivíduos com laringite crônica por refluxo laringofaríngeo

Abstract

Int rodução: A Doença do Refluxo Gastroesofágico (DRGE), chegando até a faringe e laringe, pode cursar com intensa inflamação local e rica sintomatologia (Refluxo Laringofaríngeo -RLF). Os estudos atuais não foram capazes de provar que o ácido refluído é o causador das alterações visualizadas na laringite crônica. O Fator de Crescimento Epidérmico (EGF) é um polipeptídeo produzido pelas glândulas salivares, sendo implicado na indução do crescimento epitelial, na inibição da secreção gástrica e na aceleração da cicatrização. Deficiência salivar deste fator foi encontrada na esofagite de refluxo, mas não há relatos sobre a concentração salivar de EGF em indivíduos com RLF. Objetivo: Determinar a concentração salivar do EGF em indivíduos com RLF. Forma de estudo: Caso controle. Casuística e Método: A concentração salivar de EGF de 39 indivíduos com RLF e 20 controles normais foi estudada pela técnica de ELISA. O RLF foi diagnosticado por história e exame videolaringoscópico característicos. Os 39 pacientes com RLF foram estratificados de acordo com os achados de endoscopia digestiva (com ou sem esofagite associada) e de acordo com a intensidade da laringite crônica. Foram, também, submetidos a manometria esofágica e pH-metria esofágica de 24 horas com dois canais. Resultados: Constatou-se uma concentração de EGF significativamente menor nos indivíduos com RLF quando comparados aos controles normais (p=0,002). Não houve diferença estatisticamente significante na concentração salivar de EGF entre os indivíduos com RLF, nem em relação à presença de esofagite, nem quanto à intensidade da laringite. Conclusões: Este estudo sugere que uma deficiência na concentração salivar do Fator de Crescimento Epidérmico pode estar associada à patogenia da DRGE, e que este polipeptídeo poderia ser um co-fator na gênese do RLF. Claudia

Estudo comparativo do pH e do volume salivar em indivíduos com laringofaringite crônica por doença do refluxo gastroesofágica antes e após o tratamento

“…• Recent studies in patients with LPR have shown a reduction in the salivary pH of these patients when compared to normal individuals without the disease 25,31,53,54 . It was also noticed that there is a positive correlation between the presence of laryngopharyngeal symptoms and a reduction both in volume and in saliva pH in LPR patients 53 , it is possible to establish a correlation between the presence of esophageal reflux measured through 24h esophageal pHmetry and this reduction in salivary volume and pH 54 .…”

“…In the last 12 years, many investigators and clinicians have proposed an association between Gastroesophageal Reflux Disease (GERD) and chronic laryngitis, the later representing the clinical form of the disease called Laryngopharyngeal Reflux (LPR) [1][2][3][4]8,[12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] . The larynx findings in cases of reflux laryngitis vary according to the case severity, it goes from hyperemia and mild edema of the larynx posterior third to severe cases of contact ulcers in the vocal process, exuberant scar tissue, larynx lining alterations, subglotic stenosis, even neoplastic degeneration of the epithelium 14,31,32 . According to some authors, estimates as to acid reflux causing posterior laryngitis vary greatly, coming up to 80% of the cases 14,33 .…”

“…The role of non-acid substances, such as bile and pancreatic secretions, in causing larynx lesions is still controversial because we still lack broadly available techniques to clinically measure it 33,42 . It is interesting to notice how a large number of laryngopharyngeal reflux patients, even those with the most dramatic larynx findings, do not have esophagitis or other signs of GERD in their digestive tract 8,25,29 . Of course, the gastric and esophageal mucosas protection mechanisms play a decisive role in the capacity these organs have to withstand daily mechanical and chemical aggressions, and many of these mechanisms are saliva mediated [31][32][45][46][47][48] .…”

“…It is interesting to notice how a large number of laryngopharyngeal reflux patients, even those with the most dramatic larynx findings, do not have esophagitis or other signs of GERD in their digestive tract 8,25,29 . Of course, the gastric and esophageal mucosas protection mechanisms play a decisive role in the capacity these organs have to withstand daily mechanical and chemical aggressions, and many of these mechanisms are saliva mediated [31][32][45][46][47][48] . Saliva has many organic and inorganic substances that contribute to the protection against physical and chemical aggression and also to maintain mucosal integrity, not only of the oral cavity, but also of the digestive tract 43,45,46,[48][49][50][51][52] .…”

“…Could it be some local larynx and pharynx mucosa protection factor that could be deficient or simply did not exist, making certain individuals so sensitive to this reflux? Eckley's study (2002) 25 suggests that there is, in fact, a deficit of epider-mal growth factor (EGF) in the salivary secretion, such substance is produced by the salivary glands, besides a significant alteration in the salivary pH of individuals with chronic laryngitis due to LPR, when compared to their normal counterparts. Notwithstanding, we do not know if these salivary alterations, both quantitative and qualitative, are innate or if they develop along one's life span.…”