Robustness of the approximate likelihood of the protracted speciation model.

The protracted speciation model presents a realistic and parsimonious explanation for the observed slowdown in lineage accumulation through time, by accounting for the fact that speciation takes time. A method to compute the likelihood for this model given a phylogeny is available and allows estimation of its parameters (rate of initiation of speciation, rate of completion of speciation and extinction rate) and statistical comparison of this model to other proposed models of diversification. However, this likelihood computation method makes an approximation of the protracted speciation model to be mathematically tractable: it sometimes counts fewer species than one would do from a biological perspective. This approximation may have large consequences for likelihood-based inferences: it may render any conclusions based on this method completely irrelevant. Here, we study to what extent this approximation affects parameter estimations. We simulated phylogenies from which we reconstructed the tree of extant species according to the original, biologically meaningful protracted speciation model and according to the approximation. We then compared the resulting parameter estimates. We found that the differences were larger for high values of extinction rates and small values of speciation-completion rates. Indeed, a long speciation-completion time and a high extinction rate promote the appearance of cases to which the approximation applies. However, surprisingly, the deviation introduced is largely negligible over the parameter space explored, suggesting that this approximate likelihood can be applied reliably in practice to estimate biologically relevant parameters under the original protracted speciation model.

Prognostic significance of serial determinations of lactate dehydrogenase (LDH) in the follow-up of patients with myelodysplastic syndromes.

BACKGROUND: Early recognition of disease progression in low-risk myelodysplastic syndromes (MDS) is an important decision point concerning intensive therapies. In a screen program searching for dynamic prognostic determinants, we have identified lactate dehydrogenase (LDH) as a most suitable follow-up parameter. PATIENTS AND METHODS: LDH levels were serially determined in 221 patients with de novo MDS (median age 70 years, range 24-94). The increase in LDH was correlated with survival and acute myeloid leukemia (AML) evolution. RESULTS: Confirming previous data, an elevated LDH at diagnosis was found to be associated with an increased probability of AML evolution and decreased probability of survival (P < 0.05). In the follow-up, we found that in patients who progressed (to higher IPSS category or AML), LDH levels were significantly higher in the two 3-month period preceding progression compared with the initial two 3-month period (P < 0.005). In a subgroup of patients, the increase in LDH was accompanied or followed by other signs of disease progression, such as occurrence of thrombocytopenia or appearance of circulating blasts. In multivariate analyses, the LDH increase was found to be an independent prognostic variable. CONCLUSIONS: LDH is an interesting follow-up parameter in MDS, which may assist in early recognition of disease progression and thus help in risk stratification and patient selection for interventional therapies.

Pharmacokinetics of teicoplanin during continuous hemofiltration with a new and a 24-h used highly permeable membrane: rationale for therapeutic drug monitoring-guided dosage.

OBJECTIVE: Continuous venovenous hemofiltration (CVVH) is widely used in the management of critically ill patients, but only few administration guidelines for antimicrobial drugs are available. It is unclear whether the use of a filter for more than 24 hours might lead to less efficient extraction. This study describes the pharmacokinetics of teicoplanin during CVVH using a highly permeable membrane. METHODS: Pharmacokinetics of teicoplanin during continuous hemofiltration with a new (group 1) and a 24-h used (group 2), highly permeable polyamide membrane were assessed in 3 patients. RESULTS: The teicoplanin serum concentrations (44.0 +/- 18.5 mg/l vs 109.5 +/- 34.5 mg/l) and half-life of teicoplanin (4.6 +/- 1.1 h vs 5.2 +/- 0.7 h) differed significantly between the 2 groups indicating a smaller elimination of the drug on the second day. Substantial binding of teicoplanin to filter membranes could explain this observation. CONCLUSION: The results suggest that daily adjustment of the dosage is necessary to achieve sufficient teicoplanin concentrations and a fixed dosage recommendation is not suitable for this drug.

Suspect cell convolutes in the bone marrow of a patient with renal cell carcinoma unmasked as atypical convolutes of hairy cells.

We describe a patient who concomitantly presented with renal cell carcinoma (RCC) and hairy cell leukemia (HCL). Hairy cells formed atypical cell convolutes on bone marrow smears that might have been mistaken for tumor metastases.

Survival analysis and AML development in patients with de novo myelodysplastic syndromes: comparison of six different prognostic scoring systems.

A number of prognostic scoring systems for patients with myelodysplastic syndromes (MDS) have been introduced in the past. In the present study, survival and AML evolution were analyzed retrospectively in a total of 180 patients with de novo MDS (observation period: 1989-1999; median age: 71; range 27-93; f/m ratio: 1/1.2). Diagnoses were established according to FAB criteria (RARS, n=37; RA, n=53; RAEB, n=50; RAEB-t, n=19; CMML, n=21). Six different multiparameter scoring systems (the Mufti, Aul, Sanz, Morel, and Toyama scores, and the international prognostic scoring system [IPSS]) were applied. The Aul, Sanz, and Mufti scores were applied to all 180 patients, Morel and Toyama scores to 109 patients, and the IPSS to 102. As assessed by multivariate analysis, the percentage of bm-blasts, hemoglobin, platelet count, neutrophil count, LDH, and karyotype were found to be independent single variables for survival, and bm-blasts, neutrophil count, platelet count, and karyotype for AML evolution. All prognostic scoring systems applied appeared to be highly predictive for survival and AML development (P<0.001). The highest predictive values were found for the Aul, Sanz, and Toyama scores for overall survival, and the IPSS, Toyama, and Morel scores for AML-free survival. In summary, our data show that scoring systems are useful for predicting overall and AML-free survival in patients with MDS. Karyotype-based multiparameter systems appear to be particularly effective in defining MDS patients who are at high risk of transforming to leukemia.

Prognostic value of lactate dehydrogenase activity in myelodysplastic syndromes.

Several prognostic factors for patients with myelodysplastic syndromes (MDS) have been defined in the past. One of these factors appears to be the serum lactate dehydrogenase (LDH) activity. However, the precise predictive value of an elevated LDH level with regard to AML transformation remains uncertain. In this study, the prognostic value of the LDH activity was examined in a cohort of 180 patients with de novo MDS (median age 71 years [27-93]; f/m-ratio 1:1.2; RA: n=53; RARS: n=37; RAEB: n=50; RAEBT: n=19; CMML: n=21). Significant differences in LDH activities were found among FAB groups (P<0.05), and especially among IPSS groups (HIGH: 411+/-574; INT-2: 221+/-90; INT-1: 254+/-145; LOW: 192+/-47 U/l; P<0.05). An LDH level of >/=300 U/l was found to be associated with a significantly shorter median survival (10.3 months) when compared to <300 U/l (33.7 months; P<0.01). Moreover, an LDH activity of >/=300 U/l indicated a reduced AML-free survival in our MDS patients (P<0.01). As assessed by Cox regression, the inclusion of LDH as additional variable into the IPSS system resulted in an improved prediction concerning survival, but not with regard to AML evolution. Together, our data show that a serum LDH activity of >/=300 U/l in MDS is associated with a significantly shorter survival and higher risk to transform to AML. The LDH activity should be considered as an important prognostic factor in MDS.

The new hematology analyzer Sysmex XE-2100: performance evaluation of a novel white blood cell differential technology.

CONTEXT: The new hematology analyzer Sysmex XE-2100 (TOA Medical Electronics, Kobe, Japan) has a novel, combined, white blood cell differential technology and a special reagent system to enumerate nucleated red blood cells. DESIGN: Performance evaluation of both technologies of the Sysmex XE-2100 according to the H20-A protocol of the National Committee for Clinical and Laboratory Standards and comparison of the results with those for the hematology analyzer Sysmex NE-8000 (TOA Medical Electronics). SPECIMENS: Five hundred forty-four blood samples randomly chosen from various inpatient and outpatient departments of the Vienna University hospital. RESULTS: Five-part white blood cell differential counts on the XE-2100 revealed excellent correlation with the manual reference method for neutrophils, lymphocytes, and eosinophils (r =.925,.922, and.877, respectively) and good correlation for monocytes and basophils (r =.756 and.763, respectively). The efficiency rates of flagging for the presence of >/=1% abnormal white blood cells were 83% (XE-2100) and 66% (NE-8000). The correlation of automated and microscopic nucleated red blood cell counts was excellent (r =.97). CONCLUSIONS: From the present evaluation and our former experience with other types of Sysmex analyzers, we conclude that the new white blood cell differential technology of the XE-2100 represents a further development toward more efficient flagging of abnormal white blood cells.

Single-dose pharmacokinetics of levofloxacin during continuous veno-venous haemofiltration in critically ill patients.

The present study was performed to analyse the pharmacokinetics of levofloxacin during continuous veno-venous haemofiltration (CVVH) with a high-flux polyamide membrane. Twelve patients received 500 mg levofloxacin intravenously. The mean levofloxacin concentration peak was 1.9 +/- 1.0 mg/L. The elimination half-life, haemofiltration clearance and total removal were 8.3 +/- 2.6 h, 27.6 +/- 8.4 mL/min and 56 +/- 19%, respectively. Further multiple-dose studies are required to enable dosage recommendations to be made for patients receiving renal replacement therapy with CVVH.

Fludarabine therapy in Waldenström's macroglobulinemia.

Seven patients with macroglobulinemia (six previously untreated, one with minimal pretreatment) were treated with fludarabine (25 mg/m2/day for 5 days, repeated every 4 weeks). The median age was 58 years. The time from diagnosis to treatment with fludarabine was 4.5 months to 175 months (median 32.6 months). The patients received six (n =5), five (n =1), and three (n = 1) courses of fludarabine. One patient showed only a slight decrease of immunoglobulin (Ig) M (from 5,750 mg/dl to 4,700 mg/dl) and no improvement of anemia. Therefore, treatment was stopped after three cycles. In the other six patients, a marked reduction of IgM levels (from 6,140 mg/dl to 1,220 mg/dl median), a normalization of hemoglobin (from 10.8 g/dl to 12.3 g/dl median), a reduction of lymphocyte count (from 1992/>microl to 652/microl median), and a reduction of beta2 microglobulin (from 2.3mg/l to 1.8 mg/l median) were achieved. A 50% IgM reduction was achieved 5.4 months (median) after the beginning of therapy, and the maximum response was observed 17.3 months (median) after the end of treatment. The responses were sustained without further therapy in six patients for 20.8-55.2 months. In one patient, disease progression was observed 12.5 months after the end of therapy. Fludarabine therapy was well tolerated with few side effects. In three patients, febrile episodes occurred. No opportunistic infections were recorded. We conclude that fludarabine is an effective treatment in previously untreated or in minimally pretreated patients with Waldenström's macroglobulinemia.

Multiple-dose pharmacokinetics of cefepime in long-term hemodialysis with high-flux membranes.

OBJECTIVE: Among uremic patients on hemodialysis, infectious complications leading to a high incidence of morbidity and mortality are a well-documented problem. In this multi-dose study, the safety, tolerance, and pharmacokinetics of cefepime during high-flux hemodialysis were investigated and an improved dosing schedule is presented. METHODS: Six long-term hemodialysis patients received 2 g cefepime i.v. at the end of hemodialysis three times per week. RESULTS: Trough levels of cefepime were 23.3 +/- 7.3 mg/l and peak serum concentrations 165.6 +/- 48.7 mg/l. After 3.5 h of high-flux hemodialysis, 72.2 +/- 6.4% of cefepime was eliminated. The intradialytic half-life was 1.6 +/- 0.29 h and the interdialytic half-life 22.0 +/- 2.14 h. CONCLUSION: A dosage of 2 g cefepime after each hemodialysis session achieved drug levels well above the minimal inhibitory concentration (MIC)90 for most of the target pathogens. Thus, the described dosing schedule is an efficient and cost saving antmicrobial therapy for severe infections in long-term hemodialysis patients with no residual renal function.

Prolonged third remission in a patient with acute promyelocytic leukemia after consolidation chemotherapy with intermittent intermediate dose ara-C and maintenance with intermittent all-trans retinoic acid (ATRA).

The benefit of all-trans-retinoic acid (ATRA) in the front line therapy of acute promyelocytic leukemia (APL) is well established, but its role in postremission therapy and in the treatment of relapse is currently under investigation. Moreover, the impact of cytosine arabinoside (Ara-C) in the therapy of APL has been questioned in recent studies. We report a prolonged third molecular remission (MR) in a patient with hyperleukocytotic APL after induction with ATRA, consolidation chemotherapy (CT) with intermittent intermediate dose Ara-C and maintenance therapy with intermittent ATRA. While the first two remissions were relatively short (8 months and 11 months, resp.), the duration of the third continuous CR (49+ months) is more than twice as long as the length of the two previous remissions combined. In this case Ara-C followed by intermittent ATRA maintenance was a safe and effective therapy for relapsed disease. A third molecular remission of such duration and quality is unusual.

Role of immunological lymphocyte subset typing as a screening method for lymphoid malignancies in daily routine practice.

BACKGROUND: The major diagnostic role of peripheral lymphocyte subset typing is to distinguish between malignant and reactive conditions. METHODS: The present study evaluates the screening efficacy of flow cytometric lymphocyte subset typing for the presence of a lymphoid malignancy. Four hundred samples were analyzed with a combination of anti-T-, B-, and natural killer (NK)-cell monoclonal antibodies. RESULTS: Two hundred and twenty (55%) samples showed a normal distribution of lymphocyte subsets, 73 (18%) samples exhibited unspecific alterations of lymphocyte subsets, 19 (5%) samples exhibited a reactive phenotype typical of Epstein-Barr virus/cytomegalovirus (EBV/CMV) infection, and 88 (22%) samples expressed a phenotype suggestive of lymphoma. The most predictive independent factor of a lymphoma-specific phenotype was the absolute lymphocyte count (P = 0.0001, odds ratio 73.225). Seventy-eight percent of samples containing >/=4 x 10(9)/l lymphocytes and 2% of samples with lymphocyte counts <4 x 10(9)/l exhibited a lymphoma-specific phenotype. The specificity of the referring clinical comment was the second best predictor of a lymphoma-specific typing outcome (P = 0.0001, odds ratio 19.589). The independent predictive values of lymphocyte morphology and of relative lymphocyte counts were of borderline significance. CONCLUSIONS: The use of flow cytometric lymphocyte subset typing as a diagnostic screening method for lymphoma should be restricted to cases of unexplained elevation of absolute lymphocyte counts with or without morphological atypias and to cases with definite clinical symptoms of lymphoma.

Macrocytic anemia and thrombocytosis associated with thymoma: a case report.

Thymomas are often associated with autoimmune disorders. We report on a 45-year-old female patient with thymoma and hypogammaglobulinemia (Good's syndrome) who developed symptomatic macrocytic anemia (Hb 4.4 g/dl, MCV 112 fl) and thrombocytosis (Plt 442 G/l). Besides hypogammaglobulinemia (IgG 589 mg/dl), an inverted ratio of CD4(+)/CD8(+) cells was seen. The bone marrow biopsy showed a slightly hypercellular bone marrow with normal granulopoiesis, normal megakaryopoiesis and a mild dyserythropoiesis without any ring-sideroblasts. The in-vitro stem cell culture from the bone marrow revealed an atypical growth of macroclusters, reduced BFU-E and CFU-GEMM colony growth, whereas the CFU-GM colony growth was within the normal range. The chromosomal analysis showed a normal karyotype. The plasma vitamin B(12) and folate levels were within normal ranges, and we could not detect any autoantibodies. These findings excluded the differential diagnoses pure red cell aplasia (PRCA) and pernicious anemia. After resection of the thymoma of mixed cell type, the macrocytic anemia and thrombocytosis disappeared. The clinical course was complicated by a cerebral palsy and a life-threatening fungal septicemia after surgery. In the third year after thymectomy, hyporegenerative macrocytic anemia and thrombocytosis reappeared and an immunosuppressive treatment with prednisolone (1 mg/kg BW) was started. After initiation of the prednisolone therapy, reticulocyte counts increased and macrocytic anemia as well as thrombocytosis disappeared. The normalization of these laboratory parameters during glucocorticoid therapy suggests that in rare cases the constellation of macrocytic anemia, thrombocytosis and hypogammaglobulinemia may be due to an underlying immunologic mechanism.

Monitoring of minimal residual leukemia in patients with MLL-AF9 positive acute myeloid leukemia by RT-PCR.

Twenty-seven patients with AML and MLL gene rearrangement were analyzed by a reverse transcriptase polymerase chain reaction (RT-PCR) for the MLL-AF9 translocation. The MLL-AF9 fusion transcript was detected in six patients. In five patients, the breakpoint of the AF9 gene was located within the recently described site A; in one patient, a novel breakpoint (AF9 site D) mapped to a position 377 bp 3' of site A. Five patients could be serially monitored for a period of 4-23 months. Two patients became two-step PCR negative in bone marrow and peripheral blood. Molecular remission was achieved rapidly after one cycle of induction chemotherapy. Both patients are in continuous complete remission (CR) at 22 and 15 months, respectively. Two patients who had achieved hematological CR did not become PCR negative and MLL-AF9 fusion transcripts were detectable in all samples after induction and consolidation chemotherapy. One patient relapsed 5 months after achieving CR. The other patient received allogeneic bone marrow transplantation from an HLA-identical sibling 2 months after achieving hematological CR and became PCR negative 4 weeks after transplantation. In the fifth patient, hematological CR could not be achieved with two cycles of intensive induction chemotherapy, and MLL-AF9 transcripts were present in all samples tested. Our data indicate that MLL-AF9 RT-PCR is specific for the t(9;11) translocation. PCR negativity can be achieved in responding patients already 1 month after induction chemotherapy. The fast reduction of MLL-AF9 positive blast cells below the detection limit of RT-PCR seems to be a prerequisite for long-term CR. The results of RT-PCR may be useful for treatment decisions (eg BMT).

Continuous infusion versus intermittent administration of meropenem in critically ill patients.

This prospective crossover study compared the pharmacokinetics of meropenem by continuous infusion and by intermittent administration in critically ill patients. Fifteen patients were randomized to receive meropenem either as a 2 g iv loading dose, followed by a 3 g continuous infusion (CI) over 24 h, or by intermittent administration (IA) of 2 g iv every 8 h (q8h). Each regimen was followed for a period of 2 days, succeeded by crossover to the alternative regimen for the same period. Pharmacokinetic parameters (mean +/- SD) of CI included the following: concentration at steady state (Css) was 11.9+/-5.0 mg/L; area under the curve (AUC) was 117.5+/-12.9 mg/L x h. The maximum and minimum serum concentrations of meropenem (Cmax, Cmin) and total meropenem clearance (CItot) for IA were 110.1+/-6.9 mg/L, 8.5+/-1.0 mg/L and 9.4+/-1.2 L/h, respectively. The AUC during the IA regimen was larger than the AUC during CI (P < 0.001). In both treatment groups, meropenem serum concentrations remained above the MICs for the most common bacterial pathogens. We conclude that CI of meropenem is equivalent to the IA regimen and is therefore suitable for treating critically ill patients. Further studies are necessary to compare the clinical effects of CI and IA in this patient group.

Post-transplant acute myeloid leukemia (PT-AML).

Acute myeloid leukemia following organ transplantation (PT-AML) is a rare event with only a few published cases in the literature. We present three patients who developed AML (FAB M1, M5, M4) after renal, double lung or liver transplantation. Molecular analysis detected a t(9;11) in one patient and documented the recipient origin of AML in a second patient. All patients were treated with chemotherapy. Immunosuppression was reduced to cyclosporin A (CsA) and prednisone in two patients and to prednisone alone in one patient. Two patients achieved a complete remission (CR), with a remission duration of 4.6 months in one patient, the other patient died from septicemia after 15.2 months in CR. One patient was refractory to chemotherapy and died from septicemia. This report together with the documented cases in the literature suggests that PT-AML (1) develops after a median interval of 5 years after transplantation with variable latency (range, <1-17 years); (2) is heterogeneous with respect to FAB classification; (3) shows chromosomal and molecular changes typical of therapy-related AML (t-AML: -7, +8, 11q23, inv16, t(15;17)); (4) standard chemotherapy is feasible after reduction of immunosuppression and produces a CR rate of 56% with a median remission duration of 4.6 months and an overall survival of 2.6 months; (5) the major complications are early death (25%), gram-negative septicemia, progressive disease or relapse. This review provides diagnostic and therapeutic experiences and guidelines for the management of this increasing group of post-transplant patients.

Competitive CBFbeta/MYH11 reverse-transcriptase polymerase chain reaction for quantitative assessment of minimal residual disease during postremission therapy in acute myeloid leukemia with inversion(16): a pilot study.

PURPOSE: (1) Quantification of minimal residual disease (MRD) by competitive CBFbeta/MYH11 reverse-transcriptase polymerase chain reaction (RT-PCR) in patients with acute myeloid leukemia (AML) and inversion(16) [inv(16)] during postremission therapy, (2) comparison of this method with conventional two-step RT-PCR, and (3) evaluation of a potential prognostic value. PATIENTS AND METHODS: MRD of six consecutive adult patients with AML and inv(16)(p13;q22) or t(16;16)(p13;q22) who entered complete remission (CR) was monitored by competitive CBFbeta/MYH11 RT-PCR in their bone marrow (BM) during postremission therapy with high-dose cytarabine (HiDAC) or after BM transplantation with a matched unrelated-donor marrow (MUD-BMT) during an observation period of 4.5 to 27 months after initiation of treatment. RESULTS: Competitive PCR showed a gradual decline by at least 4 orders of magnitude after 7 to 9 months in patients in continuous CR (CCR), while one patient who relapsed after 13.5 months only achieved a reduction by 2 orders of magnitude at the end of consolidation therapy. A rapid decrease below the detection limit was observed within 1 month in two patients after MUD-BMT. A temporary reappearance of molecular MRD was observed in these patients during immunosuppression for graft-versus-host disease (GvHD). After reduction of immunosuppression, the level of MRD dropped again below the PCR detection limit. Molecular monitoring by conventional two-step RT-PCR yielded comparable results only when multiple assays per time point were performed, while single-assay RT-PCR gave misleading results. CONCLUSION: Competitive RT-PCR is a valuable tool for molecular monitoring during postremission chemotherapy, as well as after BMT.

Automated five-part white blood cell differential counts. Efficiency of software-generated white blood cell suspect flags of the hematology analyzers Sysmex SE-9000, Sysmex NE-8000, and Coulter STKS.

OBJECTIVE: The present study evaluates the efficiency of software-generated white blood cell (WBC) "suspect flags" of the hematology analyzers Sysmex SE-9000, Sysmex NE-8000, and Coulter STKS. DESIGN: Automated WBC differential counts were considered positive if they contained any suspect WBC flag indicating the presence of blasts, myeloid precursor cells, or abnormal lymphocytes. Reference differential counts were performed by microscopic examination of 400 WBCs per sample. After comparison to the reference method, automated differential counts were classified as true-positive, true-negative, false-positive, and false-negative. The flagging efficiency of analyzers was expressed as a percentage of subjects correctly classified. SPECIMENS: Four hundred sixty-seven blood samples were randomly chosen for comparison analysis from various inpatient and outpatient departments of the Vienna university hospital, Austria. RESULTS: The efficiency rates of flagging for the presence of > or = 1% abnormal WBCs were 78% (SE-9000), 77% (NE-8000), and 72% (Coulter STKS). The flagging efficiencies were best for samples with normal WBC counts. With regard to the specific suspect flags, the flagging of blast cells was most efficient on all analyzers. CONCLUSIONS: Our results demonstrate the comparable overall performance of three analyzers, SE-9000, NE-8000, and Coulter STKS. They further underscore the importance of critical interpretation of automated differential counts, because at a detection limit of > or = 1% abnormal WBCs > 20% of samples were not correctly flagged by either analyzer.

Single-dose pharmacokinetics of teicoplanin during hemodialysis therapy using high-flux polysulfone membranes.

Teicoplanin is a new glycopeptide antibiotic with potent activity against Gram-positive bacteria. It has been considered to be non-dialyzable due to its high molecular weight (1875-1891 d) and high protein binding (89%). Therefore, a reduced dose was recommended for patients on hemodialysis therapy, with the loading dose being followed by a considerably lower maintenance dose and/or extension of the interval between doses. The present study was performed to evaluate the pharmacokinetics of teicoplanin during hemodialysis therapy using high flux membranes. The pharmacokinetic parameters of teicoplanin were studied in 15 patients with chronic renal failure on hemodialysis. A high flux polysulfone membrane (ultrafiltration coefficient of 40 ml/h/mmHg) was used. Teicoplanin was administered at a dosage of 10 mg.kg-1 body weight in 100 ml isotonic saline solution during the first 10 minutes of hemodialysis therapy. Pharmacokinetic analysis was performed using a three compartment analysis. After a single dose of teicoplanin plasma peak levels were 26.4 +/- 12.0 micrograms/mL (mean +/- SD) after 30 minutes. Teicoplanin concentrations rapidly declined to a nadir of 6.1 +/- 2.5 micrograms/mL at the end of the 3.5-hour session dialysis. Extracorporeal clearance was 39.7 +/- 24.5 mL/min. Removal of 19.3 +/- 7.7% of the drug was estimated if infused during hemodialysis. T 1/2 alpha were 0.37 +/- 0.25 hrs, t 1/2 beta 20.1 +/- 7.1 hrs, and t 1/2 gamma 549.7 +/- 210.5 hrs. We conclude that teicoplanin levels are reduced to a subtherapeutic range during one single high-flux dialysis session if the drug is administered during hemodialysis. Thus, in contrast to previous suggestions relevant amounts of teicoplanin are removed during hemodialysis and thus teicoplanin cannot be viewed as non-dialyzable drug. We recommend obligatory drug monitoring to achieve therapeutic plasma concentrations.

Evaluation of a total hematology analysis system (Sysmex HS-430). Benefits for large laboratories by reducing manual work load and optimizing screening efficacy for pathologic samples.

In this study, the authors evaluated a closed tube total hematology analysis system, Sysmex HS-430 (HS), which consists of two automated hematology analyzers, Sysmex NE-8000, the reticulocyte analyzer, Sysmex R-3000, and a slide preparation unit integrated in an automated sample transport system (TOA Medical Electronics, Kobe, Japan). The suitability of the system was compared with a conventional hematology system (CS) consisting of two single standing Coulter STKS analyzers (Hialeah, FL), one automated reticulocyte counter Sysmex R-1000, and the manual blood smear preparation. Evaluation was performed following the concept suggested by the Austrian-German societies for Clinical Chemistry and Laboratory Medicine that includes the evaluation of personnel supply. Eight consecutive series with a total of 4,896 samples were analyzed on both systems. Evaluation revealed that the analysis time per series was 238 minutes on the HS-430 and 359 minutes on the CS. The mean analyzer down times because of technical reasons were 36 minutes on the HS and 32 minutes on the CS. The down time because of "nontechnical" reasons was 31 minutes on the HS-430, but 173 minutes on the CS, which was mainly because of discontinuous sample loading of analyzers of the CS. The average direct technical time effort for complete blood cell count (CBC) analyses, reticulocyte counts, and blood smear preparations per series was 23 minutes on the HS and 245 minutes on the CS. In summary, these data show that an automated system like the HS-430 saves 222 minutes of manual activities arising in a large routine hematology laboratory with a mean throughout of 612 samples per day. Furthermore, the system improves intralaboratory turnaround times, avoids human errors by automated sample identification, and guarantees more safety for laboratory staff by minimizing the contact with potential biohazards.