Abstract: 【Abstract】Background Clinically, hepatitis B virus (HBV) infection has been observed to be associated with nephropathy. Regular monitoring of renal function is recommended because comorbidities or antiviral treatment might further increase the renal injury. The well-established formulae using serum creatinine for the calculation of glomerular filtration rate (eGFR) are validated only for patients with substantially impaired renal function but not suitable for monitoring patients with normal renal function. There are few data of early renal injury evaluated in patients with chronic HBV infection. Methods A multicenter, retrospective and observational study was carried out in 2 hospitals in Tianjin, China between April 2012 and June 2013. The study recruited 90 patients with chronic HBV infection who never received antiviral treatment. Based on the hepatitis status, they were divided into three groups including chronic hepatitis group, liver cirrhosis group, and hepatic carcinoma group. Patients were assessed for early renal injury by urinary albumin, urinary transferrin,urinary IgG, and serum β2-microglobulin. Clinical information and other laboratory data including serum creatinine and eGFR were also collected for diagnosis. Patients’data from two laboratories were pooled together and analyzed among the three groups. Logistic regression analysis was conducted to determine the association between early renal injury and the variables including age, gender, comorbidities (diabetes and hypertension), and chronic disease stages. Results Serum creatinine level was in normal range in all patients. However, the abnormal rate of albumin, transferrin, IgG in urine, and serum β2-microglobulin were much higher than that of eGFR (72.2% vs. 12.7%, c2=56.25, P=0.000). The proportion of early renal injury was different in different status of chronic HBV infection. In patients with chronic hepatitis, cirrhosis and liver cancer, urinary transferrin levels were 1.91±1.06 mg/L, 2.66±3.01 mg/L, and 6.73±8.32 mg/L, (c2=7.671, P=0.001), respectively; abnormal urinary IgG level was found in 4/30 (13.3%), 15/29 (51.7%) and 11/30 (36.7%) (F=10.39, P=0.006), respectively of the patients; abnormal β2-microglobulin level was found in 10/30 (33.3%), 18/29 (62%) and 23/30 (76.7%) (F=12.75, P=0.00), respectively of the patients. Logistic regression analyses showed that aged patients and liver disease status were the independent risk factors for early abnormal renal function in patients with chronic HBV infection. Conclusions The prevalence of early renal injury with normal eGFR is higher in patients with HBV infection. Age and disease status are the main factors affecting the early renal injury. Assessment of early renal injury is required before antiviral treatment in these patients.

Key words: Hepatitis B Virus, Estimated Glomerular Filtration Rate, Liver Cirrhosis