Precore and core promoter mutants are associated with higher HBeAg seroconversion but low disease remission rates in HBV patients treated with nucleos(t)ide analogues.

HBeAg seroconversion in HBV patients is considered an important event. We determined precore (PC) and base core promoter (BCP) mutations in 137 HBeAg-positive nucleos(t)ide analogues (NA) treated patients by INNO-LiPA HBV PreCore assay (Innogenetics). The majority of patients with nongenotype A had PC/BCP mutants present at baseline (P = 0.02). During 29 months of therapy, 45 patients achieved HBeAg seroconversion. Probability of HBeAg seroconversion was higher in patients with PC and/or BCP mutants (P = 0.01). After HBeAg seroconversion, patients with BCP mutants had more HBeAg relapse (P = 0.07), and PC mutants less often achieved HBV DNA < 2000 IU/mL (P = 0.07).

Hepatitis B surface antigen monitoring and management of chronic hepatitis B.

Serum hepatitis B surface antigen (HBsAg) levels reflect intrahepatic hepatitis B virus (HBV) covalently closed circular DNA and may be a valuable addition to HBV DNA in the management of patients with chronic hepatitis B (CHB). Among HBeAg-negative CHB patients with low HBV DNA levels, HBsAg quantification may help distinguish those with active CHB from true inactive carriers with a very favourable prognosis, thus limiting the need for long-term intensive monitoring of ALT and HBV DNA levels. In patients treated with peginterferon (PEG-IFN), achievement of a decline in HBsAg during therapy appears to be an important marker for treatment outcome, and several groups have proposed stopping rules based on HBsAg thresholds. A recently described stopping rule incorporating a combination of HBsAg and HBV DNA levels can accurately identify HBeAg-negative patients, especially those with HBV genotype D, not responding to PEG-IFN. Current applications of HBsAg levels in the monitoring of patients treated with nucleo(s)tide analogues are still being evaluated. First data from these studies show that HBsAg decline, and thus subsequent clearance, is confined to those with an active immune response to HBV, such as HBeAg-positive patients with elevated ALT, or those who achieve HBeAg clearance.

[The return of the hepatitis delta virus]. / De terugkeer van het hepatitis delta-virus.

- There are several regions worldwide with a high prevalence of infection with the hepatitis delta virus (HDV) in hepatitis B virus (HBV) carriers.- Chronic HDV infection is occurring with increasing frequency due to increased immigration.- HDV transmission can take place through the same routes as HBV by simultaneous infection with both viruses (co-infection) or infection of an HBV carrier with HDV (superinfection).- Delta hepatitis is considered as the most severe form of viral hepatitis with a high risk of progression to cirrhosis and hepatocellular carcinoma.- Chronic delta hepatitis is exclusively observed in patients who are HBV carriers.- Pegylated interferon is currently the only registered therapy for patients with delta hepatitis, but leads to a persistent virological response in only a minority of them, and rarely leads to a complete cure.- New antivirals, such as viral entry blockers, prenylation inhibitors and anti-sense oligonucleotides are promising and currently being investigated in phase 2 trials.

Fluid, electrolyte and acid-base disorders associated with antibiotic therapy.

Antibiotics are among the most frequently prescribed drugs in medicine. Their use, however, is often limited by associated renal toxic effects. The most common manifestation of these toxic effects is decreased glomerular filtration rate. However, they can also occur while renal function remains near to normal. This Review focuses on antibiotic-associated fluid, electrolyte and acid-base disorders that do not greatly reduce glomerular filtration. Renal tubules can be affected by antibiotics at various locations. In the proximal tubule, toxic effects of tetracyclines and aminoglycosides can result in complete proximal tubular dysfunction, also known as Fanconi syndrome. Aminoglycosides (and capreomycin) can also affect the loop of Henle and lead to a Bartter-like syndrome. In the collecting ducts, antibiotics can cause a diverse range of disorders, including hyponatremia, hypokalemia, hyperkalemia, renal tubular acidosis, and nephrogenic diabetes insipidus. Causative antibiotics include trimethoprim, amphotericin B, penicillins, ciprofloxacin, demeclocycline and various antitubercular agents. Here, we describe the mechanisms that disrupt renal tubular function. Integrated with the physiology of each successive nephron segment, we discuss the receptors, transporters, channels or pores that are affected by antibiotics. This insight should pave the way for pathophysiology-directed treatment of these disorders.