Enteral nutrition by nasogastric tube in adult patients treated with intensive chemotherapy for acute leukemia.

In this study, nutritional status 3 wk after starting 20 induction course of chemotherapy with enteral nasogastric tube feeding was compared to the nutritional status after 35 courses with a normal oral hospital diet. Tube feeding consisted of 2000 to 3000 cal daily of a hospital made pasteurized formula or sterile Nutrison RTS. In the group fed by nasogastric tube the mean weight loss was significantly smaller (p less than 0.01) and there were fewer patients with a severe weight loss of more than 5% during the first 3 wk (p less than 0.01) than in the hospital diet group. Serum albumin reduction of more than 10% was present in 4/20 and 23/35 for each group respectively (p less than 0.01). Bacterial contamination occurred in the pasteurized hospital-made formula which led to Pseudomonas septicemia in one patient. During a short-term catabolic state (3 wk) sterile feeding by nasogastric tube can prevent weight loss and hypoalbuminemia in most patients. Bacteriological control of the food and supply system is mandatory in granulocytopenic patients.

Isolation of hepatitis B surface antigen (HBsAg) by affinity chromatography on antibody-coated immunoadsorbents.

Hepatitis tb surface antigen (HBsAg) was isolated from human serum by two steps of affinity chromatography on antibody-coated gels. HBsAg-positive serum was passed through a column packed with guinea pig anti-HBsAg antibodies covalently bound to CNBr-activated beaded agarose gel. The majority of non-specifically bound proteins was removed by washing the gel with increased concentrations (0.5 M) of NaCl in Tris buffer. Elution of the specifically bound HBsAg was carried out with 3 M NaSCN. Residual normal human serum proteins present in the eluate were removed by passing the partially purified HBsAg through an immunoadsorbent coated with rabbit antibodies directed against human serum proteins. After this treatment normal human serum proteins could no longer be demonstrated by passive hemagglutination in the isolated HBsAg. Cross-reactions between HBsAg and normal human serum proteins could not be demonstrated. Both antibody-coated immunoadsorbents could be used over ten times without significant loss of their binding capacity.

Treatment of advanced Hodgkin's disease with high dose melphalan and autologous bone marrow transplantation.

Twenty patients with Hodgkin's disease which had relapsed at least once after chemotherapy, were treated with melphalan 140-220 mg/m2 i.v. followed by reinfusion of non-cryopreserved autologous bone marrow. Four patients (20%) remain alive and disease-free 28, 45, 52, and 96 months after treatment respectively. There were no treatment-related deaths. This appears to be the only reported series of patients treated with a single agent in this situation. The results are comparable to those achieved by multi-agent regimens with autologous or allogeneic bone marrow transplantation.

A method to examine the need for duplicate testing of common coagulation tests.

A statistical protocol for evaluating the need for duplicate coagulation testing was developed. It requires at least 32 sets of duplicate prothrombin times or partial thromboplastin times over the expected range of results. In addition to the statistical procedures, clinical evaluation of the duplicates is required.

Hairy cell leukemia and anti-leukocyte common antigen.

Thirty-three bone marrow biopsies from 15 patients with hairy cell leukemia (HCL) were evaluated morphologically and immunohistochemically by use of the peroxidase-antiperoxidase technique to demonstrate reactivity for leukocyte common antigen (LCA). Hairy cells in all biopsies showed a distinctive and characteristic pattern for LCA, which decorated the periphery of the cytoplasm but that left most of the cytoplasm and the nucleus unstained. Anti-LCA was particularly helpful in highlighting focal or subtle leukemic infiltrates. Hairy cells in biopsies from three patients had, on routine morphologic examination, a spindled and sarcomatoid appearance, but these too were strongly LCA positive. Treatment regimens were variable: five patients had splenectomy and received chemotherapy; five patients had splenectomy alone; and four patients had chemotherapy alone. Seven patients received interferon, and one patient received no treatment. In those six patients who had multiple biopsies as part of follow-up examinations, hairy cells as identified by anti-LCA were continuously present. Often in significant numbers, and were usually underestimated or not identified by routine examination. In those patients who received chemotherapy, qualitative alterations in the LCA reaction of hairy cells were observed.

Flow cytometric reticulocyte analysis. Multiinstitutional interlaboratory correlation study.

Reticulocyte analysis by flow cytometry offers precision and sensitivity greater than those of conventional morphologic methods and permits derivation of a reticulocyte maturity index. However, interlaboratory variability has not yet been reported. The authors analyzed 310 samples at eight sites using 11 instruments over a 4-month period to examine intermethod and interlaboratory variabilities. Stains included thiazole orange, ethidium bromide, and auramine O. Instruments included models by Coulter, Becton Dickinson, TOA Medical Electronics, and Ortho Diagnostics. The coefficient of variation (CV) among all sites and methods on these samples varied as a function of the reticulocyte percentage, ranging from a mean CV of 69% for samples with < .5% reticulocytes to 24.1% for those with > 2.5% reticulocytes. The best performance was observed with the TOA R-1000 dedicated reticulocyte analyzers, with a mean CV of 18.4% for samples with < .5% reticulocytes and 4.6% for samples with > 2.5% reticulocytes. The reticulocyte maturity index showed comparable intersite precision, with a mean CV of 16% for samples with > 2.5% reticulocytes with multipurpose flow cytometers and a mean CV of 7.3% with the TOA R-1000 instruments. Interclass correlations among all sites ranged from .79 to .99 for the reticulocyte counts and .41 to .88 for the reticulocyte maturity index. The authors conclude that flow cytometric reticulocyte analysis is more precise than manual reticulocyte analysis. With greater automation of this methodology, further interlaboratory standardization of reticulocyte counts and the reticulocyte maturity index can be achieved.

An interlaboratory study of a candidate reference method for platelet counting.

A multinational interlaboratory task force explored the important variables of platelet reference counting and developed a candidate flow cytometric reference method based on the RBC/platelet ratio. A multicenter comparison was performed to determine whether the method met the necessary criteria and was precise enough to be recommended as a new reference method. Each laboratory analyzed serial dilutions of normal specimens, stabilized material, and at least 60 patient specimens with a range of platelet counts from 1 to 400 x 10(3)/microL (1-400 x 10(9)/L). Pooled analysis of the serial dilutions showed that RBC-platelet and RBC-RBC coincidence events became negligible at sufficiently high dilutions (i.e., > 1:1,000). All laboratories demonstrated excellent intra-assay and acceptable interlaboratory precision. Two antibodies (CD61 and CD41) were used for identifying platelets and individually gave acceptable results, but in a minority of samples, staining differences were observed. The optimum method thus uses a double-labeling procedure with a final dilution factor of 1:1,000. The study demonstrated that this method meets the criteria for a reference platelet count.

Plasma spermidine concentrations as early indication of response to therapy in human myeloma.

Eighteen patients with melphalan refractory myeloma were treated with vindesine and prednisone. Plasma spermidine concentrations were measured by radioimmunoassay before and after a single vindesine injection. Seven patients showed a significant rise of plasma spermidine after vindesine and five of these showed a clinical response on further evaluation. Of the 11 patients who did not show raised spermidine concentrations, 10 did not respond to the therapy. The correlation between clinical response/rise of spermidine and between non-response/no rise of spermidine was statistically significant (p less than 0.05). Pretreatment spermidine concentrations did not distinguish those who responded to treatment nor did they differ in patients and controls.

Reticulocyte maturity as an indicator for estimating qualitative abnormality of erythropoiesis.

AIMS: To determine the maturity of reticulocytes in patients with anaemia as a result of various haematological disorders including those with qualitative abnormalities such as ineffective erythropoiesis or dyserythropoiesis. METHODS: The number of mature reticulocytes was measured with flow cytometry in venous blood samples from 122 patients with haematological disorders and 100 healthy controls. Reticulocytes were classified into three categories by the fluorescence intensity of auramin O staining: low fluorescence ratio (LFR), medium fluorescence ratio (MFR), and high fluorescence ratio (HFR). Immature reticulocytes were determined as the aggregate of MFR and HFR (%). RESULTS: The mean (2SD) number of immature reticulocytes in 100 normal subjects was 9.0 (7.0)%. Significantly high mean values of immature reticulocytes with a normal or reduced reticulocyte count were shown in 90 patients with dyserythropoietic or ineffective erythropoietic conditions, such as acute myeloid leukaemia (AML) (n = 37), myelodysplastic syndrome (MDS) (n = 35), aplastic anaemia (AA) (n = 8), or megaloblastic anaemia (MA), (n = 6). Reticulocyte ratios returned to normal after successful treatment of patients with AML (n = 10) and MA (n = 3). However, high percentages of immature reticulocytes with increased reticulocyte counts were consistently observed in patients with enhanced erythropoiesis such as those with acquired autoimmune haemolytic anaemias (AIHA) (n = 4) or acute blood loss (ABL) (n = 4). Reticulocyte maturity was within the normal range in patients with reduced erythropoiesis such as occurs in chronic renal failure (CRF) (n = 11), or in iron deficiency anaemia (IDA) (n = 13). CONCLUSIONS: The evaluation of reticulocyte maturity with total reticulocyte count seems to be clinically useful for estimating the qualitative impairment of erythropoiesis, and so could help differentiate haematological disorders.

Phytohemagglutin-induced lymphocyte cytotoxicity in hemodialysis patients with hepatitis B virus infection.

Phytohemagglutinin (PHA)-induced or primary cytotoxicity in vitro which is mediated by T lymphocytes, was studied during hepatitis B virus (HBV) infection in 45 hemodialysis patients, and related to liver cell damage and recovery. HBsAg positive patients with raised transaminases had increased primary cytotoxicity similar to nine otherwise healthy subjects with acute hepatitis B. HBsAg positive patients with normal transaminases showed decreased primary cytotoxicity and recovered patients showed normal values. Increased primary cytotoxicity could not be attributed to an increase in T lymphocytes, as all groups of hemodialysis patients had decreased lymphocyte and T-lymphocyte counts without significant differences between them. In the follow-up study none of the 13 HBsAg positive patients with normal transaminases recovered. However, five of the 18 patients with raised transaminases did recover from hepatitis B, accompanied by a decrease in cytotoxicity. These results show that an increased PHA-induced lymphocyte cytotoxicity corresponds with the occurrence of liver cell damage and subsequent recovery in hemodialysis patients with HBV infection. This suggests that cytotoxic T lymphocytes are involved in liver cell damage and recovery in HBV infection.

Random errors in haematology tests: a process control approach.

Random errors are usually not detected by classic quality-control methods, because these can occur not only during the analytical procedure itself, but during any step of the entire process of generating test results: from patient specimen collection till the final result is being charted. Random errors therefore require a variety of methods for prevention and detection. Process control enables the analysis of the causes and categories of random error, while it also assists in the design and implementation of methods for prevention and detection. In this paper the various aspects of such an approach are discussed. Among the suggested measures that will reduce the frequency of random error are: specimen labels with machine-readable codes, application at the site of specimen collection; instrument interfacing to a laboratory computer system; and streamlining of data entry. Recommendations for random error detection systems include parameter-flagging criteria, internal consistency checks of test results, and delta checking. These measures need to be part of a systems approach to be most successful, and will result in a significant reduction, although not in a complete elimination, of both the incidence of random errors and the frequency with which test results containing random errors will be reported.

The use of inference strategies in the differential diagnosis of microcytic anemia.

A new expert system developed on a Macintosh personal computer using a commercially available artificial intelligence shell was compared with four different discriminant functions (DFs) for the differentiation of microcytic anemia into etiologic categories. Several databases were used with a different composition but all contained at least some samples from thalassemic individuals and from patients with iron deficiency anemia. The DFs analyzed were those proposed by England and Fraser, Green and colleagues, Mentzer, and by Shine and Lal. None of the databases performed satisfactorily when used singly, whereas very high false-positive rates were obtained by one of them. The diagnostic efficiency was somewhat improved by combining several DFs. An expert system using an artificial intelligence "shell" with an "interference engine" was developed using cluster analysis and a set of learning examples. The input necessary for the system to achieve a conclusion consists of MCV, RBC, and RDW as well as a statement as to whether the patient has anemia. Based upon the values of these parameters, the expert system will give an "advice" regarding the probabilities for thalassemia, iron deficiency, and/or other probabilities such as previous transfusions, anemia of chronic disease, laboratory error, etc. In a prospective trial, the system functioned with an accuracy of better than 85%.

The spun micro-haematocrit and mean red cell volume are affected by changes in the oxygenation state of red blood cells.

In this study we examined the effects of in vitro oxygenation and deoxygenation on the spun micro-haematocrit (packed cell volume or PCV) and the electronically measured mean cell volume (MCV) and haematocrit (Hct) of red blood cells. Because PCV and/or MCV and Hct are being used for calibration of haematology analysers, it is important that their potential variability caused by outside factors is known. We found that these parameters did vary with the oxygenation state of the erythrocyte and conclude that the effect is most likely caused by a combination of water shifts due to intracellular carbamate and bicarbonate formation, and conformational changes in haemoglobin. The results of the study have implications for whole blood calibration and for short term imprecision assessments of automated haematology analysers. To ensure consistent results, we recommend that blood specimens be fully oxygenated before reference work or reproducibility studies of MCV, Hct and/or PCV are attempted.

Specific lymphocyte stimulation by purified, heat-inactivated hepatitis-B antigen.

The ability of purified, heat-inactivated hepatitis-B antigen (HBAg) to stimulate sensitized lymphocytes in vitro was investigated with the lymphocyte stimulation test on lymphocytes from three groups of individuals. Stimulation was minimal in the lymphocytes of two out of 15 normal controls, whereas lymphocytes from nine out of 12 patients who had recovered from hepatitis B showed stimulation, as did lymphocytes from five out of 12 laboratory technicians who had been regularly exposed to HBAg but who had no history of hepatitis or signs of it in the previous two years. No differences were observed in the responses to phytohaemagglutinin of lymphocytes from persons in the three groups. HBAg and HBAg inactivated by heat were shown in immunodiffusion to be immunologically identical. Inactivated HBAg stimulated antibody production in guinea-pigs. These findings suggest that not only humoral but also cell-mediated immunity might be induced by vaccination with purified, heat-inactivated HBAg.