Evaluation of continuous constant current and continuous pulsed current in sweat induction for cystic fibrosis diagnosis

Autor(es)

Souza Gomez, Carla Cristina ^{[1, 2]} ; Lima Marson, Fernando Augusto ^{[1, 2, 3]} ; Servidoni, Maria Fatima ^{[1, 2, 4]} ; Ribeiro, Antonio Fernando ^{[1, 2]} ; Goncalves Oliveira Ribeiro, Maria Angela ^{[1, 2]} ; Lopes Gama, Veruska Acioli ^{[5, 6, 7]} ; Costa, Eduardo Tavares ^{[5, 6]} ; Ribeiro, Jose Dirceu ^{[1, 2]} ; Vieira Junior, Francisco Ubaldo ^{[5, 6, 7]}

Afiliação do(s) autor(es)

^[1] Univ Estadual Campinas, Sch Med Sci, Dept Pediat, Cidade Univ Zeferino Vaz, BR-13083887 Campinas, SP - Brazil

^[2] Univ Estadual Campinas, Ctr Res Pediat, Sch Med Sci, Cidade Univ Zeferino Vaz, BR-13083887 Campinas, SP - Brazil

^[3] Univ Estadual Campinas, Dept Med Genet, Sch Med Sci, Cidade Univ Zeferino Vaz, BR-13083887 Campinas, SP - Brazil

^[4] Univ Estadual Campinas, Gastrocentroendoscopy Unit, Cidade Univ Zeferino Vaz, BR-13083872 Campinas, SP - Brazil

^[5] Univ Estadual Campinas, Ctr Biomed Engn, Cidade Univ Zeferino Vaz, BR-13083970 Campinas, SP - Brazil

^[6] Univ Estadual Campinas, Fac Elect & Comp Engn, Dept Biomed Engn, Cidade Univ Zeferino Vaz, BR-13083881 Campinas, SP - Brazil

^[7] Fed Inst Educ Sci & Technol, Campus Campinas, Km 143-5, BR-13069901 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: BMC PULMONARY MEDICINE; v. 18, SEP 14 2018.
• Citações Web of Science: 0

Resumo

Background: The sweat test (ST) is the gold standard for the diagnosis of cystic fibrosis (CF). However, little is known about sweat induction using different types of currents and waves. In this context, our objective was to develop a device to induce sweat and compare the use of continuous constant current (CCC) and continuous pulsed current (CPC) in individuals with CF and healthy controls. Methods: A prospective cross-sectional study with experimental intervention. The variables of gender, ethnicity, age, and body mass index (BMI) were considered. The method of Gibson and Cooke was used, and the following markers were evaluated: sweat weight, electrical impedance, sufficient sweat amount, and CF diagnosis. Triangular (TPC) or sinusoidal (SPC) pulsed current was applied to the right arm, and CCC was applied to the left arm. Results: The study analyzed 260 individuals, 141/213 (54.2%) were female participants, 135/260 (51.9%) were Caucasians. The distribution of individuals by concentration of chloride at the ST was: (CF) 26/260 (10%); (borderlines) 109/260 (41.9%); (healthy) 97/260 (37.3%); (insufficient weight in sweat) 28/260 (10.8%). No association was observed between the sufficient sweat amount to perform the ST when we compared the currents. However, the SPC showed a higher amount of sweat weight. Using Bland and Altman plot considering the agreement between the sweat chloride values achieved from CPC {[}SPC and TPC] and CCC, there was no proportional bias and mean values are unrelated and only explain less than 8% of the variation. Moreover, TPC presented higher electrical impedance when compared with SPC and CCC. SPC presented lower electrical impedance and higher sweat weight than CCC. Male participants presented lower electrical impedance and higher sweat weight with CCC and TPC, and higher sweat weight with SPC. Conclusions: The evaluated currents are safe and able to induce and produce sweat in sufficient quantities for the ST. SPC presented lower electrical impedance when compared with other currents. The use of SPC is recommended to induce sweat in patients with sweat problems. Finally, ethnicity, gender, age and BMI did not influence sweat induction at the ST, and no side effect was observed in our study. (AU)

• Processo FAPESP: 11/12939-4 - Associação entre polimorfismos de genes moduladores em crianças e adolescentes com asma alérgica e não alérgica: leve, moderada e grave
• Beneficiário: Fernando Augusto de Lima Marson
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 15/12858-5 - Identificação das mutações prevalentes e caracterização clínica e funcional de crianças e adultos com discinesia ciliar primária
• Beneficiário: Fernando Augusto de Lima Marson
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 15/12183-8 - Identificação das mutações prevalentes e caracterização clínica e funcional de crianças e adultos com discinesia ciliar primária
• Beneficiário: Jose Dirceu Ribeiro
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 11/18845-1 - Associação entre polimorfismos de genes moduladores em crianças e adolescentes com asma alérgica e não alérgica leve, moderada e grave
• Beneficiário: Jose Dirceu Ribeiro
• Modalidade de apoio: Auxílio à Pesquisa - Regular