Role of serum (1 3)--ß-d-glucan assay in early diagnosis of invasive fungal infections in a neonatal intensive care unit / O papel do (1 3)-ß-d-glucano no soro no diagnóstico precoce de infecções fúngicas invasivas em uma unidade de terapia intensiva neonatal

Abstract Objectives: To study the microbiological pattern of late onset neonatal sepsis cultures and to assess the diagnostic performance of serum (1,3)-β-d-glucan level for early diagnosis of invasive fungemia in high-risk infants admitted to a neonatal intensive care unit. Methods: A prospective multicenter clinical trial conducted on infants at high risk for invasive fungal infections, with suspected late onset sepsis, admitted to a neonatal intensive care unit at Mansoura University Children's Hospital and Mansoura General Hospital between March 2014 and February 2016. Results: A total of 77 newborn infants with high risk of invasive fungal infection were classified based on blood culture into three groups: no fungemia (41 neonates with proven bacterial sepsis), suspected fungemia (25 neonates with negative blood culture), and definite fungemia group (11 neonates with culture-proven Candida). The growing organisms were Klebsiella spp. (14/54); Escherichia coli (12/54); Staphylococcus spp. (12/54; coagulase-negative Staphylococcus [9/54]; Staphylococcus aureus [3/54]); Pseudomonas aerouginosa (3/54); and Proteus spp. (2/54). Moreover, 11/54 presented Candida. Serum (1,3)-β-d-glucan concentration was significantly lower in the no fungemia group when compared with the definite fungemia group. The best cut-off value of (1,3)-β-d-glucan was 99 pg/mL with sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 63.6%, 95.1%, 77.8%, 90.7%, and 88.5%, respectively. Conclusion: (1,3)-β-d-glucan assay has a limited sensitivity with excellent specificity and negative predictive value, which allow its use as an aid in exclusion of invasive neonatal fungal infection. Accurate diagnosis and therapeutic decisions should be based on combining (1,3)-β-d-glucan assay with other clinical, radiological, and microbiological findings.

Resumo Objetivos: Estudar o padrão microbiológico das culturas de sepse neonatal de início tardio e avaliar o desempenho diagnóstico do nível de (1,3)-β-D-glucano no soro para diagnóstico precoce de fungemia invasiva em neonatos de alto risco internados em uma unidade de terapia intensiva neonatal. Métodos: Ensaio clínico multicêntrico prospectivo conduzido em neonatos internados em uma unidade de terapia intensiva neonatal com suspeita de sepse de início tardio que estavam em risco de infecções fúngicas invasivas no hospital universitário infantil de Almançora e no hospital geral de Almançora entre março de 2014 e fevereiro de 2016. Resultados: Foram classificados 77 neonatos recém-nascidos com risco de infecção fúngica invasiva, com base na hemocultura, em: grupo sem fungemia, incluindo 41 neonatos com sepse bacteriana comprovada, grupo com suspeita de fungemia, incluindo 25 neonatos com hemocultura negativa; e grupo com fungemia definida, incluindo 11 neonatos com Candida comprovada por cultura. Os organismos em crescimento foram: {Klebsiella spp 14/54; E. coli 12/54; Staphylococcus spp 12/54 (Staph coagulase negativa 9/54; Staph aureus 3/54); pseudomonous aerouginosa 3/54 e Proteus spp 2/54}, além de 11/54 Candida. A concentração de (1,3)-β-D-glucano no soro foi significativamente inferior no grupo sem fungemia em comparação ao grupo com fungemia definida. O melhor valor de corte da (1,3)-β-D-glucano foi 99 pg/mL com sensibilidade, especificidade, valor preditivo positivo, valor preditivo negativo e precisão de 63,6%, 95,1%, 77,8%, 90,7% e 88,5%, respectivamente. Conclusão: O ensaio de (1,3)-β-D-glucano possui sensibilidade limitada com especificidade e valor preditivo negativo excelentes que possibilitam seu uso e ajudam na exclusão de infecção fúngica invasiva neonatal. O diagnóstico preciso e as decisões oterapêuticas devem ter como base a combinação di ensaio de (1,3)-β-D-glucano com outros achados clínicos, radiológicos e microbiológicos.

Serum markers as an aid in the diagnosis of pulmonary fungal infections in AIDS patients

ABSTRACT Introduction: The etiology of pulmonary infections in HIV patients is determined by several variables including geographic region and availability of antiretroviral therapy. Materials and methods: A cross-sectional prospective study was conducted from 2012 to 2016 to evaluate the occurrence of pulmonary fungal infection in HIV-patients hospitalized due to pulmonary infections. Patients' serums were tested for (1-3)-β-D-Glugan, galactomannan, and lactate dehydrogenase. The association among the variables was analyzed by univariate and multivariate regression analysis. Results: 60 patients were included in the study. The patients were classified in three groups: Pneumocystis jirovecii pneumonia (19 patients), community-acquired pneumonia (18 patients), and other infections (23 patients). The overall mortality was 13.3%. The time since diagnosis of HIV infection was shorter in the pneumocystosis group (4.94 years; p = 0.001) than for the other two groups of patients. The multivariate analysis showed that higher (1-3)-β-D-Glucan level (mean: 241 pg/mL) and lactate dehydrogenase (mean: 762 U/L) were associated with the diagnosis of pneumocystosis. Pneumocystosis was the aids-defining illness in 11 out of 16 newly diagnosed HIV-infected patients. Conclusion: In the era of antiretroviral therapy, PJP was still the most prevalent pulmonary infection and (1-3)-β-D-Glucan and lactate dehydrogenase may be suitable markers to help diagnosing pneumocystosis in our HIV population.

Evaluación del rendimiento de 1, 3-β -d-glucano como apoyo diagnóstico de infecciones invasoras por Candida spp. en pacientes críticos adultos / The 1,3-β -d-glucan in critical adult patients as diagnostic tool for invasive Candida spp. infection, performance evaluation

Resumen Introducción: La enfermedad fúngica invasora (EFI) se reconoce como causa importante de morbi-mortalidad en pacientes críticos. La mayoría de estas infecciones son provocadas por Candida spp. para cuyo diagnóstico existen importantes limitaciones. Objetivo: Realizar una evaluación inicial de la utilidad de la medición del 1,3-β-D- glucano (BDG) como herramienta diagnóstica de apoyo de las infecciones invasoras por Candida spp. en pacientes críticos. Pacientes y Método: Estudio prospectivo de pacientes mayores de 18 años hospitalizados en unidades de pacientes críticos por más de cinco días, con fiebre sin foco claro y dos o más factores de riesgo para EFI por Candida spp. Se obtuvieron muestras para BDG en dos días consecutivos. Los resultados se confrontaron con el diagnóstico definitivo de candidemia/candidiasis invasora (C/CI) demostrado según cultivos. Resultados: El valor promedio de BDG en los pacientes con diagnóstico de C/CI fue 224,3 ± 213,7 pg/ml y en aquellos sin C/CI 63,8 ± 76,7 pg/ml (p: 0,02). La sensibilidad y especificidad de BDG para diagnóstico de C/CI fue 60 y 92%, respectivamente. El valor predictor positivo fue 60% y el valor predictor negativo de 92%. Conclusión: BDG puede considerarse como un examen de apoyo en el diagnóstico de C/CI en pacientes críticos con factores de riesgo.

Background: Invasive fungal infections are important causes of morbimortality in critical patients. Most of these infections are caused by Candida spp. which diagnosis has important limitations. Aim: Initial evaluation of the utility of 1,3-β-D-glucan (BDG) as a diagnostic tool for invasive candida infections in critical patients. Patients and Methods: Adult patients over 18 years old, hospitalized in intensive care units for more than five days, with fever > 38 °C of unclear origin and two or more risk factors for invasive Candida spp. infection were included. Samples for BDG were obtained on two consecutive days. The results were compared with definitive diagnosis of candidemia/invasive candidiasis (C/IC) confirmed by cultures. Results: Median value of BDG in patients with C/IC was 224.3 ± 213.7 pg/ml and in patients without C/IC was 63.8 ± 76.7 pg/ml (p: 0.02). Sensitivity and specificity for the diagnosis of C/IC were 60 and 92%, respectively. Positive predictive value was 60% and negative predictive value was 92%. Conclusion: BDG could be considered as a complementary diagnostic tool for the diagnosis of C/IC in critical patients with risk factors.