High rates of early HBeAg seroconversion and relapse in Indian patients of chronic hepatitis B treated with Lamivudine: results of an open labeled trial

Background  

The use of Lamivudine in chronic hepatitis B (CHB) is well known, however the reported rate of HBeAg sero-conversion and its durability post-treatment have varied considerably. We undertook the present study to study the effect of Lamivudine on HBeAg loss and seroconversion rates in Indian patients of CHB in relation to frequency, predictors and durability.     

Variation in blood sample collection for determination of hemodialysis adequacy. Council on Renal Nutrition National Research Question Collaborative Study Group

Inadequate dialysis has been associated with high morbidity and mortality in end-stage renal disease (ESRD) patients receiving maintenance hemodialysis. The accurate estimation of dialysis adequacy, measured either as a calculated urea kinetics (Kt/V) or a simple urea reduction ratio (URR) is dependent on the proper collection of blood samples for predialysis and postdialysis blood urea nitrogen (BUN) determination. Because no established protocol exists for blood sampling, we surveyed the study cohort of dialysis centers participating in the National Kidney Foundation Council on Renal Nutrition National Research Question Collaborative Study to determine the comparability of BUN data that were collected to calculate URR to determine adequacy of dialysis. Surveys were completed by 100% of the 202 units participating: 195 in the United States (from 43 states) and seven from Canada, treating approximately 15,000 hemodialysis patients in total. The distribution of the sample by the type of facility mirrored that of 1996 United States Renal Data System (USRDS) Annual Report facilities data. Results showed a 5.0% error in predialysis blood draw and an 8.4% to 41.6% error in the postdialysis counterpart. There was a large variability in the observed postdialysis methods in general. Dilution of predialysis sample with either heparin or saline will falsely underestimate Kt/V and URR. The presence of access-derived, recirculated blood in the postdialysis sample will falsely overestimate Kt/V and URR. Excessive delay in drawing postdialysis sample will reduce Kt/V and URR because of urea rebound. Adoption by all dialysis providers of a uniform blood sample draw procedure will result in a consistency necessary to allow reliable and valid comparison of adequacy of dialysis parameters within and between ESRD patients, units, and clinical trials.     

Multimeric composition of factor VIII/von Willebrand factor following administration of DDAVP: implications for pathophysiology and therapy of von Willebrand's disease subtypes

We have studied the modifications in the multimeric composition of plasma factor VIII/von Willebrand factor and the bleeding time response following administration of 1-Deamino-[8-D-arginine]-Vasopressin (DDAVP) to patients with different subtypes of von Willebrand's disease. In type I, all multimers were present in plasma in the resting state, though they were decreased in concentration. Administration of DDAVP resulted in an increased concentration of these forms as well as the appearance of larger forms than were previously present. There was concomitant correction of the bleeding time. In type IIA, large multimers were absent in the resting state, and although DDAVP induced an average threefold increase in the plasma concentration of factor VIII/von Willebrand factor, the larger multimers did not appear and the bleeding time, although shortened, was not corrected. In contrast, the larger multimers that were also absent from type IIB plasma in the resting state rapidly appeared following DDAVP administration. However, their appearance was transitory and the bleeding time, as in IIA patients, was shortened but not corrected. The characteristic multimeric composition of platelet factor VIII/von Willebrand factor in given subtypes predicted the alteration in plasma factor VIII/von Willebrand factor induced by DDAVP. These studies provide evidence that the different subtypes of von Willebrand's disease represent distinct abnormalities of factor VIII/von Willebrand factor. They also suggest that complete hemostatic correction following DDAVP can be routinely expected only in type I von Willebrand's disease, and only if factor VIII/von Willebrand factor can be raised to normal levels.