New index for the diagnosis of liver fibrosis in Schistosomiasis mansoni / Novo índice biológico para o diagnóstico da fibrose hepática na Esquistossomose mansoni

ABSTRACT BACKGROUND Periportal fibrosis is the major pathological consequence of the Schistosoma mansoni infection. OBJECTIVE To evaluate the accuracy of serum markers and to construct an index to assess fibrosis. METHODS Patients (n=116) with schistosomiasis were evaluated by ultrasound scan and measurements of serum levels of aminotransferases, γ-glutamyl transferase, alkaline phosphatase, hyaluronic acid, cytokines and platelets. Ultrasound images were used to evaluate the fibrosis using Niamey's classification and identified 19 patients without periportal fibrosis (patterns A and B), 48 with mild to moderate fibrosis (C and D) and 49 with advanced fibrosis (E and F). RESULTS Using multivariate analysis, a model was created, which involved alkaline phosphatase and platelets and could separate patients with different patterns of fibrosis. This index showed a better performance in separating patients without fibrosis from with advanced periportal fibrosis. The biological index showed an area under the ROC curve of 1.000. Using values below the lowest or above the highest cut-off point, the presence or absence of advanced fibrosis could be predicted in all patients. CONCLUSION The index constructed can be used to separate patients with different patterns of periportal fibrosis, specially to predict advanced fibrosis in schistosomiasis patients.

RESUMO CONTEXTO A fibrose periportal é a maior consequência patológica da infecção pelo Schistosoma mansoni. OBJETIVO Avaliar a acurácia de marcadores séricos e construir um índice para avaliar a fibrose. MÉTODOS Pacientes (n=116) com esquistossomose foram avaliados pela ultrassonografia e dosados os níveis de aminotransferases, γ-glutamil transferase, fosfatase alcalina, ácido hialurônico, citocinas e plaquetas. Imagens de ultrasom foram utilizadas para avaliar a fibrose através de classificação de Niamey e identificados 19 pacientes sem fibrose periportal (padrão A e B), 48 com fibrose média a moderada (C e D) e 49 com fibrose avançada (E e F). RESULTADOS Através de análise multivariada, um modelo foi criado, que envolveu a fosfatase alcalina e plaquetas e conseguiu separar pacientes com diferentes padrões de fibrose periportal. Este índice mostrou um melhor desempenho em separar pacientes sem fibrose dos pacientes com fibrose avançada. O índice biológico mostrou uma área sob a curva ROC de 1,000. Usando valores infereiores e acima do ponto de corte, a presença ou ausência de fibrose avançada pode ser prevista em todos os pacientes. CONCLUSÃO O índice construído pode ser usado para separar os pacientes com diferentes padrões de fibrose periportal, especialmente para prever fibrose avançada em pacientes com esquistossomose.

Ultrasound versus biological markers in the evaluation of periportal fibrosis in human Schistosoma mansoni

In this paper, the authors review the literature and share their experience of the principal biological markers of fibrosis for the evaluation of periportal fibrosis (PPF) caused by mansoni schistosomiasis. These biological markers are compared to diagnostic ultrasound (US) scans as means of grading PPF. We also review procollagen type I and III, collagen type IV, laminin, hyaluronic acid (HA), immunoglobulin G, platelets, aspartate aminotransferase to platelet ratio index (APRI) and gamma-glutamyl transpeptidase as markers of the disease. Although there are several good markers for evaluating PPF and portal hypertension, such as HA, platelets or APRI, none can yet replace US. These markers may, however, be used to identify patients at greater risk of developing advanced disease in endemic areas and determine who will need further care and US studies.