Studies on clinical expression, genotype, and gingival crevicular fluid characteristics in young patients with Papillon-Lefèvre syndrome

Abstract: Papillon-Lefèvre syndrome (PLS) is an autosomal recessive condition with palmoplantar hyperkeratosis and aggressive periodontitis as cardinal features. The disorder is linked to mutations of the gene for cathepsin C, a lysosomal protease essential in activation of serine proteases in immune and inflammatory cells. The genetic background of the disorder has been identified, but its relation to phenotypic expression is obscure. The aims of the project were to explore phenotypic expression in young patients with PLS, and to investigate any correlation between clinical expression and identified genotype. Additionally, biochemical properties of gingival crevicular fluid (GCF) were investigated, and the result of an oral treatment protocol based on plaque control was evaluated. Major results and conclusions from the studies were:The severity of the skin lesions showed no correlation to patient’s age or level of periodontal disease, supporting the concept that the two major components of PLS are independent of each other.Genotyping revealed two cardinal genotypes, but no correlation between the identified genotypes and expression of phenotypes could be found, suggesting that it is the interaction with environmental factors and/or other genes that is important in shaping the phenotype.Analyses of gingival crevicular fluid (GCF) from patients with PLS did not show any clear-cut pathognominic expressions with regard to content of cytokines, metalloproteinases or inhibitor of metallproteinase 1.The level of plasminogen activator inhibitor in GCF was significantly higher in PLS patients than in controls, indicating atypical activity of the plasminogen activating system with, possibly, disturbed epithelial function. This may affect the epithelial barrier function and its role in the innate defence system.Evaluation of a PLS oral treatment protocol showed treatment from an early age and compliance to the program to be important in preserving permanent teeth in PLS.