Occult hepatitis B virus infection and lamivudine‐resistant mutations in isolates from renal patients undergoing hemodialysis

Abstract

HBV isolates with the identified substitutions have the potential to spread silently by nosocomial transmission within the hemodialysis unit. These results have potential implications for the management of patients with occult HBV infection undergoing hemodialysis.

Specific Amino Acid Substitutions in the S Protein Prevent Its Excretion In Vitro and May Contribute to Occult Hepatitis B Virus Infection

“…Similarly, the single mutation W74L has been reported to suppress the retention phenotype of L77R (16). A Y100C substitution was present in two pattern 3 OBI clones (HK8663-cl2 and TW3437-cl5) in agreement with previous reports associating this substitution with HBsAg-negative phenotype in OBI cases (12,(19)(20)(21). However, it was also found in all pattern 2/3 clones of the M92 control, indicating that Y100C does not play a direct role in reducing total HBsAg amounts or HBsAg reactivity with commercial assays, as suggested by Mello and coauthors (12).…”

Infecção oculta pelo vírus da hepatite B em comunidade amazônica submetida a intenso fluxo migratório, estado do Pará, Brasil

“…Estudos comprovaram a existência de alta prevalência da IOB entre dialisados, entretanto a prevalência de IOB entre receptores de transplante renal é controversa 27,28,29,30,31,32 28,29 .…”

Hepatitis B Virus (HBV) Variants in Hemodialysis Patients

“…Parenteral exposure also favors contamination by HCV (Dai et al, 2001). The studies performed up to now on hemodialysis patients provide widely divergent results, reporting a prevalence of occult HBV that ranges from 0% to 36% (Besisik et al, 2003;Fabrizi et al, 2005;Goral et al, 2006;Kanbay et al, 2006;Minuk et al, 2004;Motta et al, 2010;Siagris et al, 2006). These apparent discrepancies may be explained by significant differences in the prevalence of HBV infection in different geographic regions and/or by the detection limits of different HBV-DNA assays.…”

“…Y100C has been found in cases of occult HBV infection among Venezuelan blood donors (Gutierrez et al, 2004), individuals from an Afro-Brazilian community (Motta-Castro et al, 2008) and HIV-HBV co-infected patients . Among hemodialysis patients with occult HBV infection, the Y100C mutation has been also frequently found (Motta et al, 2010). Due to these observations, the role of Y100C substitution in reducing amount of HBsAg or changing HBsAg affinity by commercial antibodies was recently investigated by Mello and cols.…”

“…There are concerns about HBV variants detected in cases of occult infection, if they may be transmitted to other hemodialysis patients and whether or not they may cause liver disease. Interesting, two studies, one performed in Turkey (Besisik et al, 2003) and other in Brazil (Motta et al, 2010), reported high prevalence of lamivudine resistant mutations in a significant proportion of hemodialysis patients with occult HBV infection, who had not previously received lamivudine treatment. It has been demonstrated that rtM204V/I mutants have a markedly decreased replication phenotype compared with wild-type HBV (Melegari et al, 1998), whereas both rtV173L and rtL180M substitutions act as compensatory changes that partially restore the replication fitness of the virus Ono et al, 2001).…”