Journal de la Faculté de Médecine
Volume 2, Numéro 4, Pages 303-310
2018-06-30

Apport De La Réaction De Polymérisation En Chaîne (pcr) Dans Le Diagnostic De La Tuberculose Cutanée

Auteurs : Chiali Amel . Khelil Amel . Mahmoudi Naziha Hayet . Dali Ali Abdessamed . Khodja Aomar Ammar .

Résumé

Abstract Introduction - Tuberculosis is still a public health problem. The anatomo-clinical polymorphism, the multiplicity of differential diagnoses and the fickle isolation of mycobacteria often make it difficult to diagnose the cutaneous localization of this infectious disease. The objective of this study is to evaluate the contribution of the polymerase chain reaction (PCR) in the diagnosis of cutaneous tuberculosis by comparing it with the other techniques wich are culture on solid medium and the histological study. Materials and methods -This is amulticenter observational studyincluding 46 patients recruited from different dermatology departments in Oran, Tlemcen and Algiers. These patients present a strongly suspected active cutaneous tuberculosis with or without an extra-cutaneous localization and have never received antituberculous treatment. The diagnostic test used isXpert® MTB / RIF for biopsy fragments of cutaneous lesions and pus when it exists. Statistical analysis was performed usingEpi Data 3.1 software.A comparison of the results of the polymerase chain reaction (PCR), culture and histology with those found in other studies using conventional PCR has been established. Results - The comparison of the PCR and the culture results showed in a global way, a sensitivity of 71.5%, a specificity of 100%, a Positive Predictive Value of 100% and a Negative Predictive Value of 88.9% (p<0.001). Comparison of results obtained with Xpert® MTB / RIF and those of histology, estimated sensitivity at 20.5%, specificity at 71.4%, positive predictive value at 81.2% and a value of predictive negative at 13.9% (p = 0.63). Conclusion - The sensitivity of Xpert® MTB / RIF is lower than that of culture and that of histology for the diagnosis of cutaneous tuberculosis. However, Xpert® MTB / RIF has a better specificity and shorter lead times for obtaining results.

Mots clés

Cutaneous tuberculosis; PCR; Xpert ® MTB / RIF; Culture; Histology; Sensitivity; Specificity.