Níveis plasmáticos de interleucina-1ß e interleucina-6 em recém-nascidos com febre

Abstract

Objective

To study plasma levels of interleukin-1 ß (IL-1ß) and interleukin-6 (IL-6) to diagnose bacterial infection in newborns with fever. Methods: From July 1995 to August 1996, we studied a cohort of 117 newborns 5 days old or younger, with no history of antibiotic therapy, and with clinical suspicion of bacterial infection. Those with definite criteria for sepsis were considered infected. Fever was defined as axillar temperature > 37.5°C in three independent measurements. The patients were classified in four different groups: Group 1: infected with fever; Group 2: infected without fever; Group 3: not infected with fever; Group 4: not infected without fever. Laboratory findings for complete blood count, platelet count, blood or other fluid cultures, and plasma levels of IL-1ß and IL-6 were collected before the beginning of antibiotic therapy. Results: Of the 117 newborns studied, 66 were infected. Fever was present in 45 (38.46%). The median values of IL-1ß and IL-6 were significantly higher in newborns with fever than in those without fever. There were significant differences between groups 1 and 2, 1 and 4, and 2 and 3 for IL-1ß. There were no significant differences between groups 2 and 4, and 1 and 3 for IL-1ß. Of the newborns without infection, 8 (72%) had fever caused by overheating, and only 3 by dehydration. There were no differences in median IL-6 levels between groups 1 and 2, and 3 and 4. There were significant differences in the median IL-6 levels between groups 1 and 3, and 1 and 4. Conclusions: IL- 6 is a marker of early neonatal sepsis. IL-1ß is associated with neonatal fever response independently of the presence of bacterial infection.

Methods

From July 1995 to August 1996, we studied a cohort of 117 newborns 5 days old or younger, with no history of antibiotic therapy, and with clinical suspicion of bacterial infection. Those with definite criteria for sepsis were considered infected. Fever was defined as axillar temperature > 37.5°C in three independent measurements. The patients were classified in four different groups: Group 1: infected with fever; Group 2: infected without fever; Group 3: not infected with fever; Group 4: not infected without fever. Laboratory findings for complete blood count, platelet count, blood or other fluid cultures, and plasma levels of IL-1ß and IL-6 were collected before the beginning of antibiotic therapy. Results: Of the 117 newborns studied, 66 were infected. Fever was present in 45 (38.46%). The median values of IL-1ß and IL-6 were significantly higher in newborns with fever than in those without fever. There were significant differences between groups 1 and 2, 1 and 4, and 2 and 3 for IL-1ß. There were no significant differences between groups 2 and 4, and 1 and 3 for IL-1ß. Of the newborns without infection, 8 (72%) had fever caused by overheating, and only 3 by dehydration. There were no differences in median IL-6 levels between groups 1 and 2, and 3 and 4. There were significant differences in the median IL-6 levels between groups 1 and 3, and 1 and 4. Conclusions: IL- 6 is a marker of early neonatal sepsis. IL-1ß is associated with neonatal fever response independently of the presence of bacterial infection.

Results

Of the 117 newborns studied, 66 were infected. Fever was present in 45 (38.46%). The median values of IL-1ß and IL-6 were significantly higher in newborns with fever than in those without fever. There were significant differences between groups 1 and 2, 1 and 4, and 2 and 3 for IL-1ß. There were no significant differences between groups 2 and 4, and 1 and 3 for IL-1ß. Of the newborns without infection, 8 (72%) had fever caused by overheating, and only 3 by dehydration. There were no differences in median IL-6 levels between groups 1 and 2, and 3 and 4. There were significant differences in the median IL-6 levels between groups 1 and 3, and 1 and 4. Conclusions: IL- 6 is a marker of early neonatal sepsis. IL-1ß is associated with neonatal fever response independently of the presence of bacterial infection.

Conclusions

IL- 6 is a marker of early neonatal sepsis. IL-1ß is associated with neonatal fever response independently of the presence of bacterial infection.

Resumen

Objetivo

Avaliar os níveis plasmáticos de IL-1β e IL-6 a fim de diferenciar a presença ou não de infecção bacteriana em recém-nascidos com febre. b Durante o período de julho de 1995 a agosto de 1996, uma coorte de 117 recém-nascidos entre zero e cinco dias de vida, sem uso prévio de antibioticoterapia e com alguma suspeita clínica de infecção bacteriana, foi estudada. Os recém-nascidos com critérios definidos para sepse constituíram os recém-nascidos infectados. Definiu-se febre como temperatura axilar > 37,5°C em três aferições independentes. Os pacientes foram classificados em quatro grupos: Grupo 1: infectados e com febre; Grupo 2: infectados e sem febre; Grupo 3: não infectados e com febre; Grupo 4: não infectados e sem febre. Foram obtidos hemograma, contagem de plaquetas, hemocultura ou qualquer outro teste de cultura, e níveis plasmáticos de IL-1β e IL-6 antes do início de terapia antimicrobiana.

Resultados

Dos 117 recém-nascidos estudados, havia 66 com infecção e 51 sem infecção. A febre esteve presente em 45 (38,46%). As medianas da IL-1β e de IL-6 foram significativamente superiores nos recém-nascidos com febre do que nos sem febre. Houve diferença significativa entre os grupos 1 e 2, 1 e 4, e 2 e 3 para IL-1β. Não houve diferença significativa entre os grupos 2 e 4, e 1 e 3 para IL-1β. Nos recém-nascidos sem infecção e com febre, a mesma ocorreu em 8 (72%) por hiperaquecimento e em apenas 3, por desidratação.Os grupos 1 e 2 e os grupos 3 e 4 não apresentaram diferença significativa no níveis de IL-6.Houve diferença significativa nos níveis de IL-6 entre os grupos 1 e 3 e os grupos 1 e 4.

Conclusões

IL-6 é um marcador de sepse neonatal precoce. IL-1β está relacionada à resposta febril do recém-nascido independente da presença de infecção bacteriana.