Chemoimmunotherapy with low-dose fludarabine and cyclophosphamide and high dose rituximab in previously untreated patients with chronic lymphocytic leukemia.

PURPOSE: Chemoimmunotherapy combining fludarabine, cyclophosphamide, and rituximab (FCR) is an active regimen for untreated patients with chronic lymphocytic leukemia (CLL) with 70% complete responses (CRs) and 95% overall responses (ORs). However, grade 3/4 neutropenia was reported in 52% of cycles of treatment. The purpose of this trial was to maintain the high responses but reduce the toxicity of FCR by decreasing the fludarabine and cyclophosphamide (FCR-Lite). PATIENTS AND METHODS: We conducted a single arm study of FCR-Lite which includes maintenance rituximab in 50 untreated CLL patients. Patients were evaluated for response using both the 1996 National Cancer Institute Working Group (NCIWG) guidelines and the 2008 guidelines. Two thirds of patients were treated by community physicians. RESULTS: The median age was 58 years (range, 36 to 85 years); 20 patients had Rai stage 1, 22 had Rai stage 2, and eight had Rai stage 3 and 4. The OR and CR rates were 100% and 79%, respectively, using the 1996 NCIWG guidelines and 100% and 77% using the 2008 guidelines. Median duration of complete response was 22.3 months (range, 5.2 to 42.5 months) and none of the complete responders have relapsed. Grade 3/4 neutropenia was noted in 13% of the cycles of therapy. CONCLUSION: FCR-Lite is highly effective in previously untreated CLL patients. Grade 3/4 neutropenia was dramatically reduced compared to standard FCR and our data demonstrated FCR-Lite can be safely administered in the community setting.

Evaluating the near-term infant for early onset sepsis: progress and challenges to consider with 16S rDNA polymerase chain reaction testing.

Although the rate of early onset sepsis in the near-term neonate is low (one to eight of 1,000 cases), the rate of mortality and morbidity is high. As a result, infants receive multiple, broad-spectrum antibiotic therapy, many for up to 7 days despite blood cultures showing no growth. Maternal intrapartum antibiotic prophylaxis and small blood volume collections from infants are cited as reasons for the lack of confidence in negative culture results. Incorporating an additional, more rapid test could facilitate a more timely diagnosis in these infants. To this end, a 16S rDNA polymerase chain reaction (PCR) assay was compared to blood culturing for use as a tool in evaluating early onset sepsis. Of 1,751 neonatal intensive care unit admissions that were screened, 1,233 near-term infants met inclusion criteria. Compared to culture, PCR demonstrated excellent analytical specificity (1,186 of 1,216, 97.5%) and negative predictive value (1,186 of 1,196, 99.2%); however, PCR failed to detect a significant number of culture-proven cases. These findings underscore the cautionary stance that should be taken at this time when considering the use of a molecular amplification test for diagnosing neonatal sepsis. The experience gained from this study illustrates the need for changes in sample collection and preparation techniques so as to improve analytical sensitivity of the assay.

Use of pyrosequencing of 16S rRNA fragments to differentiate between bacteria responsible for neonatal sepsis.

Infants admitted to neonatal intensive care units for suspicion of bacterial sepsis receive at least two broad-spectrum antibiotics for a minimum of 48 to 72 hours to cover both gram-positive and gram-negative organisms while awaiting blood culture results. On average, bacterial growth becomes detectable within 12 to 24 hours, with an additional 24 to 48 hours required for identification. We have previously described using a 16S rRNA PCR assay for screening neonatal blood for bacterial DNA. Combining PCR with DNA sequencing could prove a faster means of detecting bacteria than culture-based identification. If successful, antibiotic therapy could be appropriately tailored sooner, thus sparing infants the administration of unnecessary antibiotics. Our goal was to assess the potential of pyrosequencing to differentiate between bacteria commonly associated with neonatal sepsis. To begin, full-length sequencing of the 380-bp 16S rRNA amplicons from representative bacteria was conducted (ABI 3100) and several databases queried. These included Staphylococcus sp., Streptococcus sp., Listeria sp., and numerous gram-negative rods. The sequences from clinical isolates were identical to those present in the published databases for the same bacteria. As a result, an informative 15 bases within the 380-bp amplicon was targeted for pyrosequencing following enrichment culture and PCR amplification. A total of 643 bacterial isolates commonly associated with neonatal sepsis, and 15 PCR-positive, culture-positive neonatal whole blood samples were analyzed by pyrosequencing. Results of DNA sequencing and culture identification were compared. In summary, we were successful at using PCR and pyrosequencing together to accurately differentiate between highly diverse bacterial groups.

Comparison of three commercially available serologic assays used to detect human parvovirus B19-specific immunoglobulin M (IgM) and IgG antibodies in sera of pregnant women.

A split-sample study was conducted to evaluate the performances of three enzyme immunoassays (EIAs) utilizing one or more conformational antigens to detect human parvovirus B19 (B19V)-specific immunoglobulin M (IgM) or IgG in the sera of 198 pregnant women. We compared EIAs available from Biotrin International, Inc. (Dublin, Ireland), Medac Diagnostika (Wedel, Germany), and Mikrogen (Martinsried, Germany). Specimens with discordant results were analyzed further using an immunofluorescence assay (Biotrin). Equivocal data accounted for close to half of all the discrepant results for both IgM and IgG, with 7 of 15 discrepant results from the Medac and Mikrogen kits involving equivocal data and the Biotrin kit giving a single equivocal result. For each specimen, a consensus was established from the four test results if agreement occurred among at least three of four results. Overall, the highest percentage of agreement with the consensus results was seen when Biotrin kits were used; 194 (100%) of 194 and 194 (99.5%) of 195 results for IgM and IgG, respectively, agreed with the consensus results. When Medac kits were used, 189 (97.4%) of 194 and 191 (97.9%) of 195 results for IgM and IgG, respectively, agreed with the consensus, and when Mikrogen kits were used, 179 (92.3%) of 194 and 193 (99%) of 195 results for IgM and IgG, respectively, agreed with the consensus. Given the consensus results, the Medac EIA appeared to generate presumed false-positive results for IgM and the Mikrogen EIA appeared to generate presumed false-positive results for IgG and IgM. In summary, the Biotrin EIAs produced far fewer equivocal results than the other assays and results of the Biotrin EIAs agreed more often with the consensus results than did those of the other commercially available EIAs for detecting B19V-specific IgM and IgG antibodies.