High-vs low-dose cytarabine combined with interferon alfa in patients with first chronic phase chronic myeloid leukemia. A prospective randomized phase III study.

A prospective randomized phase III study was performed to evaluate whether intensified cytarabine would induce a higher response rate and longer event-free interval as compared to low-dose cytarabine in chronic myeloid leukemia (CML). One hundred and eighteen patients with CML in early chronic phase entered the study. Twenty-eight out of 32 patients assigned to group A received two cycles of a combination of intensified cytarabine and idarubicin followed by interferon alfa (IFN-alpha) maintenance, 28 patients in group B received standard treatment by a combination of low-dose cytarabine and IFN-alpha. Forty-nine patients with a human leukocyte antigen-identical sibling donor proceeded to allogeneic stem cell transplantation (allo-SCT) and nine patients were excluded from the analysis. Hematological response was observed in 97% of the patients in group A vs 86% of the patients in group B during the first year of treatment. In group A, 16 patients (50%) achieved a major cytogenetic response, which compared to seven patients (25%) with a major cytogenetic response in group B. With a median follow-up of 58 months (range 34-76), event-free survival was not significantly different between arms A and B. The estimated 5-year survival rate was 56% in the intensified arm and 77% in the low-dose arm (P = 0.05). Recipients of allo-SCT showed a 5-year estimated survival rate of 55%. Although intensified cytarabine induced a higher initial percentage of major and complete cytogenetic responses, responses were not sustained by IFN-alpha maintenance therapy.

Pseudo-pulmonary embolism as a sign of acute heparin-induced thrombocytopenia in hemodialysis patients: safety of resuming heparin after disappearance of HIT antibodies.

Heparin-induced thrombocytopenia (HIT) is a syndrome caused by platelet-activating antibodies that recognize complexes of platelet factor 4 (PF4) and heparin. Thrombocytopenia is the most common clinical feature of HIT. HIT can be considered as a hypercoagulable state, with a high risk of thrombosis. Another feature of HIT is an acute systemic reaction that characteristically begins 5-30 min after receiving an intravenous bolus of unfractionated heparin, such as is commonly given for hemodialysis (HD). Here we present 4 patients who developed acute HIT at or near the start of their chronic HD. All patients were anticoagulated with the low-molecular-weight heparin, nadroparin, for HD. Three of our patients underwent surgery approximately 1-2 weeks before developing HIT. All patients presented with an acute systemic reaction during HD. All patients were treated and further dialyzed with lepirudin. Under this treatment we observed a quick recovery of the platelet count, and patients remained symptom-free. Antibodies against the PF4-heparin complex were detected with a combination of a 'quick test' and an enzyme-linked immunosorbent assay test. The likelihood of having HIT previous to the detection of antibodies was estimated with the pre-test probability score criteria. The tests for PF4-heparin antibodies remained positive for an average of 165 days. Three patients underwent a rechallenge with nadroparin after disappearance of the HIT antibodies in their serum. All 3 remained symptomless when they were further hemodialyzed on nadroparin. Our observations indicate that nadroparin can be successfully reintroduced for HD anticoagulation once the patient's HIT antibodies have disappeared.

Efficacy of cisplatin-based immunochemotherapy plus alloSCT in high-risk chronic lymphocytic leukemia: final results of a prospective multicenter phase 2 HOVON study.

Allogeneic stem cell transplantation (alloSCT) remains the only curative option for CLL patients. Whereas active disease at the time of alloSCT predicts poor outcome, no standard remission-induction regimen exists. We prospectively assessed outcome after cisplatin-containing immune-chemotherapy (R-DHAP) followed by alloSCT in 46 patients (median age 58 years) fulfilling modified European Society for Blood and Marrow Transplantation (EBMT) CLL Transplant Consensus criteria being refractory to or relapsed (R/R) <1 year after fludarabine or <2 years after fludarabine-based immunochemotherapy or R/R with del(17p). Twenty-nine patients received ⩾3 cycles of R-DHAP and sixteen <3 cycles (4 because of disease progression, 8 for toxicity and 4 toxic deaths). Overall rate of response to R-DHAP was 58%, 31 (67%) proceeded to alloSCT after conditioning with fludarabine and 2 Gy TBI. Twenty (65%) remained free from progression at 2 years after alloSCT, including 17 without minimal residual disease. Intention-to-treat 2-year PFS and overall survival of the 46 patients were 42 and 51% (35.5 months median follow-up); del(17p) or fludarabine refractoriness had no impact. R-DHAP followed by alloSCT is a reasonable treatment to be considered for high-risk CLL patients without access or resistance to targeted therapies.

A single course of remission reinduction chemotherapy for acute myelogenous leukemia relapsing after allogeneic bone marrow transplantation is complicated by graft-versus-host disease and followed by sustained complete remission.

Graft-versus-host disease (GVHD) remains a major immunological complication after allogeneic bone marrow transplantation (allo-BMT), but also favors development of the beneficial graft-versus-leukemia (GVL) effect. A patient with AML-M4 (inv (16)) is described, who was given non-myeloablative remission reinduction therapy for leukemic relapse (inv (16), trisomy 8) diagnosed on day 184 after HLA-compatible sibling BMT. On day 236, ie about 6 weeks after completion of this course, a clinical syndrome suggestive of acute GVHD grade 3 had developed. Skin biopsy confirmed the clinical diagnosis of GVHD, with a compatible liver biopsy. Transfusion-associated GVHD was ruled out by analysis of short tandem repeat (STR) alleles in the skin biopsy, revealing alleles from donor and recipient but not from third party origin. Cyclosporin A (CsA) therapy, which had been tapered between days 150 and 175, was resumed, resulting in a favorable response and gradual transition to limited chronic GVHD. The patient has since remained in complete remission with an excellent performance status for more than 40 months, without further chemotherapy. Thus this biopsy proven case of GVHD was induced by marrow donor lymphocytes more than 200 days after transplantation and apparently triggered by remission reinduction chemotherapy. The case indicates that intensive non-myeloablative chemotherapy can cure AML relapsing after allo-BMT. The therapeutic effect in this case probably involved a direct pharmacological suppression of the leukemic clone followed by a GVL effect initiated by donor-derived alloreactive T lymphocytes.

Clinical and molecular features of FIP1L1-PDFGRA (+) chronic eosinophilic leukemias.

Detection of the FIP1L1-PDGFRA fusion gene or the corresponding cryptic 4q12 deletion supports the diagnosis of chronic eosinophilic leukemia (CEL) in patients with chronic hypereosinophilia. We retrospectively characterized 17 patients fulfilling WHO criteria for idiopathic hypereosinophilic syndrome (IHES) or CEL, using nested RT-PCR and interphase fluorescence in situ hybridization (FISH). Eight had FIP1L1-PDGFRA (+) CEL, three had FIP1L1-PDGFRA (-) CEL and six had IHES. FIP1L1-PDGFRA (+) CEL responded poorly to steroids, hydroxyurea or interferon-alpha, and had a high probability of eosinophilic endomyocarditis (n=4) and disease-related death (n=4). In FIP1L1-PDGFRA (+) CEL, palpable splenomegaly was present in 5/8 cases, serum vitamin B(12) was always markedly increased, and marrow biopsies revealed a distinctively myeloproliferative aspect. Imatinib induced rapid complete hematological responses in 4/4 treated FIP1L1-PDGFRA (+) cases, including one female, and complete molecular remission in 2/3 evaluable cases. In the female patient, 1 log reduction of FIP1L1-PDGFRA copy number was reached as by real-time quantitative PCR (RQ-PCR). Thus, correlating IHES/CEL genotype with phenotype, FIP1L1-PDGFRA (+) CEL emerges as a homogeneous clinicobiological entity, where imatinib can induce molecular remission. While RT-PCR and interphase FISH are equally valid diagnostic tools, the role of marrow biopsy in diagnosis and of RQ-PCR in disease and therapy monitoring needs further evaluation.

Plerixafor prescription modalities in autologous haematopoietic stem cell mobilization in Belgium.

OBJECTIVES: The efficacy and safety of plerixafor, an antagonist of the CXCR4 receptor, in combination with G-CSF has been demonstrated in patients suffering from Iymphoma and multiple myeloma (MM) eligible for autologous haematopoietic stem cell collection. However, different reimbursement criteria have been applied in different countries to select patients eligible for treatment with plerixafor. The objective of this observational study was to describe the plerixafor prescription modalities in daily practice in Belgium. METHODS: This open-label, prospective, observational study was conducted in 11 Belgian centres in 114 patients with lymphoma (Hodgkin's and non-Hodgkin's lymphoma) or MM who were treated with plerixafor according to the SmPC between April 2011 and October 2012. Patients included in another clinical trial with plerixafor were excluded from the study. RESULTS: The use of plerixafor in patients with MM or lymphoma was effective, with a success rate (defined as a total yield >2×10(6) CD34+ cells/kg) of 77%, and well tolerated (one SAE reported). Optimal collection (defined as a total yield >4×10(6) CD34+ cells/kg) was obtained for 43% of the study population (31% in lymphoma patients, compared to 61% in patients with MM). The use of plerixafor was in line with the SmPC and the Belgian reimbursement criteria for all patients. CONCLUSION: This study is showing that the use of plerixafor according to Belgian reimbursement criteria results in similar efficacy and safety as in other centres and countries worldwide.

Myelofibrosis patients in Belgium: disease characteristics.

OBJECTIVE: To date, only a small number of epidemiological studies on myelofibrosis have been performed. The current study aimed to characterize the myelofibrosis patient population in Belgium according to pre-defined disease parameters (diagnosis, risk categories, hemoglobin <10 g/dl, spleen size, constitutional symptoms, platelet count, myeloblast count), with a view to obtaining a deeper understanding of the proportion of patients that may benefit from the novel myelofibrosis therapeutic strategies. METHODS: A survey was used to collect data on prevalence and disease parameters on all myelofibrosis patients seen at each of 18 participating hematologic centers in 2011. Aggregated data from all centers were used for analysis. Analyses were descriptive and quantitative. RESULTS: A total of 250 patients with myelofibrosis were captured; of these, 136 (54%) were male and 153 (61%) were over 65 years old. One hundred sixty-five (66%) of myelofibrosis patients had primary myelofibrosis and 85 (34%) had secondary myelofibrosis. One hundred ninety-three myelofibrosis patients (77%) had a palpable spleen. About a third of patients (34%) suffered from constitutional symptoms. Two hundred twenty-two (89%) myelofibrosis patients had platelet count ≧50 000/µl and 201 (80%) had platelet count ≧100 000/µl. Of 250 patients, 85 (34%) had a myeloblast count ≧1%. Six (2%) patients had undergone a splenectomy. Thirteen (5·2%) patients had undergone radiotherapy for splenomegaly. CONCLUSIONS: The results of this survey provide insight into the characteristics of the Belgian myelofibrosis population. They also suggest that a large proportion of these patients could stand to benefit from the therapies currently under development.

Controversies in selection of epoetin dosages. Issues and answers.

Epoetin (recombinant human erythropoietin) is now a widely available though expensive treatment for the anaemia of chronic renal failure, and is effective in more than 95% of patients. Complications of epoetin in this context include hypertension in a third of cases, including hypertensive encephalopathy in a few, and thrombosis of shunts or vascular access devices. Fears that epoetin would cause progression of renal failure have not generally been confirmed, but hyperkalaemia may be a problem in the initial phase of treatment. Epoetin is up to twice as effective when administered subcutaneously rather than intravenously. Responding patients will normally do so within 3 months of starting epoetin. Failures to respond are usually due to iron deficiency or intercurrent disease. Other diseases associated with anaemia and an inappropriately low serum epoetin level include prematurity, the anaemia of cancer and rheumatoid arthritis. The baseline serum endogenous erythropoietin may provide a guide to response in some of these cases. Some encouraging results are being published. Situations where the serum erythropoietin levels are normal or elevated where epoetin has been employed include boosting of haematocrit presurgery as an adjunct to autologous blood donation, treatment of anaemic patients with myelodysplastic syndromes, and improvement of athletic performances.

Bone marrow transplantation performed as first-time treatment in two cases of secondary acute myeloid leukemia.

Two young patients with secondary acute myeloid leukemia were treated with allogeneic bone marrow transplantation as first-line treatment for their disease. High dose cytosine arabinoside was added to the conventional preparative regiment of cyclophosphamide and total body irradiation. No major problems were encountered to the immediate post-transplantation period. Complete remission of the acute myeloid leukemia was noted in both patients, with no evidence of recurrent disease at 15+ and 13 months. One patient developed severe pancytopenia 10 months after grafting with the presence of antibodies against platelets and granulocytes from the bone marrow donor. She died 3 months later from a generalised Aspergillus septicemia, probably precipitated by therapy with high doses of methylprednisolone. The other patient is alive in excellent clinical condition and in hematologic remission. Bone marrow transplantation must be taken into consideration as first-line therapy in any young patient who is suffering from a refractory type of leukemia and who has a suitable donor.

Mucormycosis in allogeneic bone marrow transplant recipients: report of five cases and review of the role of iron overload in the pathogenesis.

In a 10-year consecutive series of 263 allogeneic bone marrow transplant recipients, we identified five cases (1.9%) of invasive mucormycosis. Only one infection occurred within the first 100 days after transplantation, while the remainder complicated the late post-transplant course (median day of diagnosis: 343). Sites of infection were considered 'non-classical' and included pulmonary, cutaneous and gastric involvement. No case of fungal dissemination was observed. Mucormycosis was the primary cause of death in three of the five patients. Corticosteroid-treated graft-versus-host disease, either acute or chronic, or severe neutropenia were present in all cases. However, compared with a matched control population, the most striking finding was the demonstration of severe iron overload in each of the mucormycosis patients. The mean level of serum ferritin, transferrin saturation and number of transfused units of red cells (2029 microg/l, 92% and 52 units, respectively) in the study group is significantly higher compared with the control group (P < 0.05). The difference with other risk groups for mucormycosis, including deferoxamine-treated dialysis patients and acidotic diabetics, was analyzed in view of the possible pathogenic role of iron. Although these infections are often fatal, limited disease may have a better prognosis if diagnosed early and treated aggressively.

Treatment of patients with myelodysplastic syndromes with allogeneic bone marrow transplantation from genotypically HLA-identical sibling and alternative donors.

Between December 1981 and March 1994, 24 patients with a myelodysplastic syndrome (MDS) underwent allogeneic bone marrow transplantation (BMT) for RA with trilineage dysplasia (n = 4), CMML (n = 1), RAEB (n = 4), RAEBt (n = 9) and AML following MDS (n = 6). Fifteen patients (two RAEB, seven RAEBt and six sAML) received chemotherapy before BMT resulting in complete remission in 10 patients (six RAEBt and four sAML) at the time of BMT. Sixteen marrow donors were genotypically HLA-identical siblings. Remaining donors were other family members (five) or unrelated donors (three). The status of the underlying disease at the time of conditioning was the major factor determining long-term survival. The disease-freed survival of RA patients and patients presenting with RAEB, RAEBt and AML but transplanted in complete remission, was respectively 50 and 60%. On the contrary, none of the nine high-risk MDS patients transplanted with persistent disease, survived. Outcome after transplantation with alternative donors was inferior with one long-term survivor, mainly related to the high incidence of severe acute GVHD and its accompanying infectious complications. Six patients relapsed resulting in an actuarial probability of relapse of 28%. Twelve patients died of transplant-related complications leading to a non-relapse mortality at 5 years of 50%. At present eight patients are alive and disease-free 20 to 132 months post-transplantation resulting in an actuarial 5-year disease-free survival of 40.7%. Our results suggest that allogeneic bone marrow transplantation is a feasible treatment option for patients with MDS. However, improvement in GVHD prophylaxis and supportive care to reduce transplant-treated mortality and improved relapse prevention are imperative.

Therapy-related acute myeloid leukemia with t(8;16)(p11;p13) following anthracycline-based therapy for nonmetastatic osteosarcoma.

A case of therapy-related AML with t(8;16)(p11;p13) 14 months following the end of anthracycline-containing chemotherapy for a nonmetastatic osteosarcoma of the left tibia is presented. The patient was successfully treated with intensive remission-induction chemotherapy. Subsequently, he underwent an uncomplicated allogeneic bone marrow transplantation from his HLA-identical brother and is at present alive and disease-free 10 months after diagnosis of the secondary AML.

Translocation t(6;9) occurring in acute myelofibrosis, myelodysplastic syndrome, and acute nonlymphocytic leukemia suggests multipotent stem cell involvement.

The cytological and cytogenetic features of six patients with myeloid neoplasia and t(6;9)(p23;q34) including a case of acute myelofibrosis (AMF), a refractory anemia with excess of blasts (RAEB), and four cases of acute nonlymphocytic leukemia (ANLL) are described. Two patients in this series, both affected by ANLL type M2, presented an increase of bone marrow basophils, suggesting that this cytological-cytogenetic association is not absolute and that it may be more frequently observed in ANLL with maturation. All patients with de novo ANLL showed associated myelodysplastic features, and one patient presented a dysmyelopoietic syndrome, later evolving into ANLL. The presence of the t(6;9) in a range of myeloid neoplasias, with either concurrent myelodysplastic features or a preleukemic phase in cases of ANLL, provide evidence that this chromosome aberration may always involve a multipotent myeloid stem cell. Data on toxic exposure of the patients suggests that myeloproliferative disorders with the t(6;9) may frequently represent environmentally induced neoplasias.

Hypertension and accelerated atherosclerosis in endstage renal disease.

In patients with chronic renal failure cardiovascular morbidity and mortality are higher than in non-uremic controls. Chronic renal failure influences a number of factors that promote atherogenesis: blood pressure, nitric oxide activity, advanced glycosylation, lipid metabolism, oxidant stress, homocysteine levels, glucose metabolism and PTH. How these factors are influenced by chronic renal failure, how they interrelate and how they promote atherogenesis is still debated. Published data are for and against accelerated atherogenesis. The use of only clinical endpoints may be partially responsible for these conflicting data. Measurement of atherosclerosis itself by computerized ultrasound imaging of the common carotid arteries can be used as an outcome variable. We conclude that there is still a need for prospective, controlled, epidemiologic studies to answer the question whether or not atherogenesis is accelerated in chronic renal failure and to clarify the role of hypertension and other risk factors.

Transient acute renal failure due to tumor-lysis-induced severe phosphate load in a patient with Burkitt's lymphoma.

A patient who developed acute renal failure during a period of acute tumor lysis is reported. Evidence is presented that hyperphosphatemia and/or hyperphosphaturia caused the acute renal failure. The literature on the subject is reviewed and pathogenetic mechanisms are discussed. Therapeutic and preventive measures are outlined.

Prognostic value of a new scoring system for hospital mortality in acute renal failure.

AIM AND METHODS: In order to define a prognostic scoring system for hospital mortality of individual patients with acute renal failure (ARF), data were collected prospectively in a single centre study (Stuivenberg General Hospital, Antwerp, Belgium) on 197 adult patients consecutively admitted to the intensive care unit (ICU) during one year. Mean age was 69.8 (+/- 14.7), male/female ratio was 118/79. RESULTS: Hospital mortality was 53%, 26% of the patients who were treated with renal replacement therapy. For developing the model all parameters showing a significant difference between survivors and non-survivors were entered in the multivariate analysis. Two SHARF scores (= Stuivenberg Hospital Acute Renal Failure scores) were developed, one at the time of diagnosis of ARF (T0) and the other 48 hours later (T48): SHARF T0 (7 x age) + (6 x alb0) + (3 x PTT0) + (39 x vent0) + (9 x heartf0) + 52 SHARF T48 (7 x age) + (6 x alb0) + (3 x PTT0) + (43 x vent48) + (16 x heartf48) + 52 age, albumin (alb0) and prothrombine time (PTT0) at T0 are expressed as categories, respiratory support (vent) and heart failure (heartf) at T0 and T48 are presented as absent (0) or present (1). In the linear regression model, r2 was, respectively, 0.36 and 0.43. The area under the receiver operator characteristic (ROC) curves, judging the discrimination ability between survivors and non-survivors, for T0 and T48 were, respectively, 0.87 and 0.90. The Hosmer-Lemeshow goodness-of-fit C statistic for T0 was C = 8.47; df8; p = 0.3 89 and for T48 C = 11.05; df = 8; p = 0.199. CONCLUSION: We conclude that this scoring system, developed for all types of ARF, compares favorably with published scores and can become useful as a bedside tool for predicting hospital mortality in individual patients. A second measuring point increased the predictive value of the model. The results have to be confirmed in an ongoing prospective multicentre study.

Chronic renal failure due to renal hemosiderosis in a patient with paroxysmal nocturnal hemoglobinuria.

We report on a 44-year-old man with paroxysmal nocturnal hemoglobinuria, who developed renal hemosiderosis, interstitial nephritis, and chronic renal failure. Classically, it is assumed that the renal function is only uncommonly affected by this pathology. In most instances the renal hemosiderosis is an incidental finding at postmortem examination. In our case the presence of iron in the kidney, as confirmed by CT scan, magnetic resonance imaging and renal biopsy, occurred concomitantly with the development of renal insufficiency. A direct nephrotoxic effect of iron by the induction of highly reactive hydroxyl radicals is suggested.

Acute renal failure due to bilateral lymphomatous infiltrates. Primary extranodal non-Hodgkin's lymphoma (p-EN-NHL) of the kidneys: does it really exist?

Primary extranodal non-Hodgkin's lymphoma (p-EN-NHL) of the kidneys with acute renal failure as the only manifestation is very rare. The origin of neoplastic lymphoid cells in the kidneys, organs normally free of lymphoid tissue, is an unsolved problem. A literature review over the last ten years revealed only 9 adult cases, including ours that match the usual criteria: (1) renal failure as the initial presentation, (2) bilateral enlargement of the kidneys without obstruction and other organ or nodal involvement, (3) diagnosis only made by renal biopsy, (4) absence of other causes of renal failure, and (5) rapid improvement of renal function after radiotherapy or, as in our case, systemic chemotherapy. Autopsy on two patients confirmed that p-EN-NHL of the kidneys without dissemination does exist as a separate entity.

Comparison of different routes of administration of nadroparin in hemodialysis.

AIM: In an open, crossover, randomized study in hemodialysis patients, we investigated possible differences of the effect of the low molecular weight heparin (LMWH) nadroparin/fraxiparine in relation to the route of administration. PATIENTS AND METHODS: The effect of nadroparin, administered by the venous line or by the arterial line after priming of the extracorporeal circuit with a part of the total dose administered, was compared with administration of the same dose by the arterial line as recommended by the manufacturer. Twelve stable, chronic hemodialysis patients were studied during 3 dialysis sessions for each treatment option. Concomitant medication was kept constant. RESULTS: Results obtained after administration of nadroparin by the venous line were comparable to those obtained after administration by the arterial line. When a part of the dose was added to the priming solution, the anti-Xa activity, measured after 2 hours of dialysis, was somewhat lower (p = 0.09). There was also a tendency towards longer manual compression time in this group. There was no difference in hemoglobin, serum urea and creatinine before the study and at the end of each treatment option. CONCLUSION: We therefore conclude that the safety and efficacy of administration of LMWH by the arterial and by the venous route are identical. There is no need for addition of a small dose of LMWH to the priming fluid.

Importance of volume factors in dialysis related hypertension.

OBJECTIVE: To evaluate the relation between total body water and dialysis related hypertension. PATIENTS AND METHODS: Thirty stable chronic hemodialysis patients were studied. Twenty-four-hour ambulatory blood pressure on the day before dialysis, blood pressure before and after dialysis, weight gain, ultrafiltration and total body water were determined. Total body water was measured by body impedance analysis and expressed as percentage of dry weight (TBW %). Ambulatory blood pressure recordings were defined as hypertensive when the blood pressure load (% of readings above 140/90 mmHg) was more than 40%. RESULTS AND CONCLUSION: Patients, classified as normotensive (n = 11) or hypertensive (n = 19), based on 24-hour blood pressure measurements, had significantly different TBW % (54.7 +/- 5.3 vs. 58.9 +/- 4.6%, p = 0.046). Ambulatory blood pressure and postdialysis blood pressure, but not predialysis blood pressure, were significantly correlated with TBW %. Acute volume changes, as reflected by interdialytic weight gain and ultrafiltration did not correlate with TBW %. These changes correlated weakly with predialysis blood pressure. Multivariate analysis showed that only TBW % and antihypertensive medication had an independent influence on 24-hour blood pressure measurements. We conclude that 24-hour blood pressure and blood pressure after dialysis are better related to total body water than blood pressure before dialysis, which was however weakly related to the acute volume overload, induced by interdialytic weight gain. We hypothesize that this could be the result of a more important chronic volume overload leading to an increase in systemic vascular resistance. On the contrary the acute but less important changes in extracellular volume between dialyses cause no hypertension after dialysis and no sustained hypertension over 24 hours, but only in some cases a temporary increase in the blood pressure just before dialysis. This volume overload can be easily determined by measurement of total body water by bioelectrical impedance analysis.