The risk of major bleeding during induction chemotherapy in adolescents and adults with acute myeloid leukemia (except acute promyelocytic leukemia, which we did not study) was similar with platelet-transfusion thresholds of 20,000 per cubic millimeter and 10,000 per cubic millimeter (or 10,000 to 20,000 per cubic millimeter when body temperature exceeded 38 degrees C, there was active bleeding, or invasive procedures were needed). Use of the lower threshold reduced platelet use by 21.5 percent.

White cell (WBC) reduction, red cell (RBC) recovery, and filtration time were determined in 1-day-old standard and buffy coat-depleted RBCs filtered in the laboratory through six commercial filters for WBC reduction. Residual WBCs were counted with a Bürker chamber (BC), with a Nageotte chamber (NC), and by flow cytometry (FC). Results show that BC counts were 0 in several cases in which WBCs were detected with NC and FC, which indicated that the traditional BC method is too insensitive in use with currently available filters. Calibration curves performed by FC and with NC with samples containing known concentrations of WBCs from 1000 to 1 per microL showed that both FC and NC detected, on average, 67 percent of WBCs present in the samples (efficiency). However, the efficiency of FC showed small variability (61-70%) at different WBC levels, whereas the variability with NC was large (39-91%). This greater variability prevented the correction of NC counts by using a single factor and indicated difficulty in NC standardization. Therefore, because our main aim was to compare different filters rather than to define absolute levels of WBC contamination, uncorrected FC and NC counts were chosen to be reported. True WBC counts per unit should not exceed values that can be obtained by dividing uncorrected counts by the lowest efficiencies (61% for FC and 39% for NC). Uncorrected NC and FC counts were below 2 x 10(6) per unit in all units processed through three of the filters and below 5 x 10(6) per unit in all units processed through the other three.(ABSTRACT TRUNCATED AT 250 WORDS)

Liver transplantation (OLT) recipients who receive a graft from donors positive for hepatitis B virus (HBV) anti-core antibodies may develop overt "de novo" HBV infection. The study was undertaken to explore how often HBV infection may remain occult after OLT for hepatitis C, and whether it may represent a factor of graft fibrosis progression. We studied 30 consecutive patients transplanted for hepatitis C liver disease. Specimens from the native liver and from the graft were searched for occult HBV infection (O-HBV). In the native liver, 8/30 patients had detectable O-HBV; during the follow-up, O-HBV infection was demonstrated in 14 graft specimens. Graft O-HBV was associated with older donor age (> or =50 yr; 8/9 vs. 6/21, p < 0.005). Recipients with graft O-HBV and no O-HBV in the native liver who received their grafts from donors aged >40 yr had faster fibrosis progression than recipients with no post-transplant O-HBV, whose grafts came from donors aged >40 yr and recipients whose grafts came from donors aged < or =40 yr (4/7 vs. 1/7 vs. 2/16, p < 0.05). In OLT recipients, O-HBV is more likely to occur when grafts are obtained from aged donors and may affect the rate of fibrosis progression because of recurrent hepatitis C.

The MTHFR C677T polymorphism may play a role in influencing liver fibrosis progression in patients with recurrent hepatitis C, in conjunction with donor age, but not via steatosis promotion.