Late Breaking Abstract - The use of Xpert Ultra in the diagnosis of tuberculosis in childhood and adolescence

Abstract

<b>Introduction:</b> Xpert Ultra(Ultra) has been used, in Brazil, since 2019 and has greater sensibility than Xpert. There is a reduction in the value of the detection limit of Mycobacterium tuberculosis(M. tb.) from 116(from Xpert) to 15.6 CFU. The classification of bacillary load is: high, medium, low, and traces. In Brazil, in children(under 10 years) and in extrapulmonary tuberculosis(EPTB), the result of traces means positivity for M. tb. <b>Objective:</b> To describe the use of Ultra in a university hospital of reference for childhood tuberculosis(TB), from April 2020-March 2021, in the city of Rio de Janeiro, Brazil. <b>Methods:</b> Prospective study with children(&lt;10 years) and adolescents with suggestive EPTB or pulmonary TB (PTB) data sets collected by Ultra were included. The final diagnosis of TB was established by laboratory confirmation(Ultra), clinical data, or favorable clinical response after 60 days of treatment. The work was approved by the Ethics Committee of IPPMG-UFRJ. Results and Discussion: 29 patients were included: 28%(8/29) adolescents and 72%(21/29) children. The diagnosis of TB was established in 72%(21/29), with 59%(13/22) EPTB, 32%(7/22) PTB and 9%(2/22) combined(PTB + EPTB). The Ultra positivity was: 77%(10/13) in EPTB, being 80%(8/10) traces; in PTB 71%(5/7), being 80%(4/5) traces and in the combined 100%, being 1 exam with detected trace. Culture positivity was: 23%(3/13) and 50%(1/2) in EPTB and combined form, respectively. There was no positivity in PTB. Regarding direct bacilloscopy, there was no positivity. <b>Conclusions:</b> In both forms of TB there was a contribution of Ultra, representing an important diagnostic tool of paucibacillary forms of the disease.