Quantifying the frequency and volume of urine deposition by grazing sheep using tri-axial accelerometers.

Urine patches deposited in pasture by grazing animals are sites of reactive nitrogen (N) loss to the environment due to high concentrations of N exceeding pasture uptake requirements. In order to upscale N losses from the urine patch, several urination parameters are required, including where, when and how often urination events occur as well as the volume and chemical composition. There are limited data available in this respect, especially for sheep. Here, we seek to address this knowledge gap by using non-invasive sensor-based technology (accelerometers) on ewes grazing in situ, using a Boolean algorithm to detect urination events in the accelerometer signal. We conducted an initial study with penned Welsh Mountain ewes (n = 5), with accelerometers attached to the hind, to derive urine flow rate and to determine whether urine volume could be estimated from ewe squat time. Then accelerometers attached to the hind of Welsh Mountain ewes (n = 30 at each site) were used to investigate the frequency of sheep urination events (n = 35 946) whilst grazing two extensively managed upland pastures (semi-improved and unimproved) across two seasons (spring and autumn) at each site (35-40 days each). Sheep urinated at a frequency of 10.2 ± 0.2 and 8.1 ± 0.3 times per day in the spring and autumn, respectively, while grazing the semi-improved pasture. Urination frequency was greater (19.0 ± 0.4 and 15.3 ± 0.3 times per day in the spring and autumn, respectively) in the unimproved pasture. Ewe squat duration could be reliably used to predict the volume of urine deposited per event and was thus used to estimate mean daily urine production volumes. Sheep urinated at a rate of 16.6 mL/s and, across the entire dataset, sheep squatted for an average of 9.62 ± 0.03 s per squatting event, producing an estimated average individual urine event volume of 159 ± 1 mL (n = 35 946 events), ranging between 17 and 745 mL (for squat durations of 1 to 45 s). The estimated mean daily urine volume was 2.15 ± 0.04 L (n = 2 669 days) across the entire dataset. The data will be useful for modelling studies estimating N losses (e.g. ammonia (NH3) volatilisation, nitrous oxide (N2O) emission via nitrification and denitrification and nitrate (NO3-) leaching) from urine patches.

Full Blood Count - Internal QC Protocol: a review by the Royal College of Pathologists of Australasia Quality Assurance Programs (RCPAQAP) Pty Ltd - Haematology.

INTRODUCTION: The RCPAQAP (Royal College of Pathologists of Australasia Quality Assurance Program) Haematology has undertaken an exercise to review the internal quality control protocol for full blood count (FBC) instrumentation as well as review the action taken by laboratories when nonconforming results are evident in the RCPAQAP proficiency testing reports. METHOD: A questionnaire was sent to laboratories enrolled in the RCPAQAP FBC module. Laboratories were asked to provide information with regard to the type of control measures used within their testing environment that would trigger alerts for nonconforming events. The questionnaire also reviewed the action taken by laboratories in response to nonconforming test results in their external QA reports. RESULTS: A total of 253 of the 850 laboratories enrolled in the FBC module returned a response to the questionnaire, which identified variation in the QC protocol used to identify nonconforming events on the FBC analyser, including the type of controls, control levels processed and the frequency of use. CONCLUSION: This questionnaire identified variation in the internal QC protocol used by laboratories, including the types of control measures used and the rules applied to identify nonconforming events. However, the majority of laboratories appear to follow the most favourable choice of actions supplied when reviewing results of external QA data.

Recommendation for standardization of haematology reporting units used in the extended blood count.

INTRODUCTION: It is desirable in the interest of patient safety that the reporting of laboratory results should be standardized where no valid reason for diversity exists. This study considers the reporting units used for the extended blood cell count and makes a new ICSH recommendation to encourage standardization worldwide. METHODS: This work is based on a literature review that included the original ICSH recommendations and on data gathered from an international survey of current practice completed by 18 countries worldwide. RESULTS: The survey results show that significant diversity in the use of reporting units for the blood count exists worldwide. The use of either non-SI or other units not recommended by the ICSH in the early 1980s has persisted despite the guidance from that time. CONCLUSION: The diversity in use of reporting units occurs in three areas: the persistence in use of non-SI units for RBC, WBC and platelet counts, the use of three different units for haemoglobin concentration and the manual reporting of WBC differential, reticulocytes and nucleated RBCs when the latter are available from automated analysis or can be expressed as absolute numbers by calculation. A new recommendation with a rationale for each parameter is made for standardization of the reporting units used for the extended blood count.

Type 2M von Willebrand disease - more often misidentified than correctly identified.

INTRODUCTION: Appropriate diagnosis of von Willebrand disease (VWD), including differential identification of qualitative vs. quantitative von Willebrand factor (VWF) defects has important management implications, but remains problematic. AIM: The aim of the study was to assess whether 2M VWD, defining qualitative defects not associated with loss of high molecular weight (HMW) VWF, is often misidentified, given highly variable reported frequency ranging from 0 to ~60% of all type 2 VWD. METHODS: A comparative evaluation of laboratory ability to appropriately identify 2M VWD (n = 4) vs. HMW VWF reduction (n = 4), as sent to participants of an international external quality assessment programme. RESULTS: Laboratories had considerably greater difficulty identifying type 2M VWD, correctly identifying these on average only 29.4% of occasions, with the 70.6% error rate representing use of insufficient test panels (41.7%), misinterpretation of test results (10.0%) and analytical errors (13.3%). One type 2M case, giving a median of 49 U dL(-1) VWF:Ag, was more often misidentified as type 2A/2B VWD (46.7%) than 2M (34.8%). Another 2M case, giving a median of 189 U dL(-1) VWF:Ag, was instead often misidentified as being normal (non-VWD) (36.4%), with identifications of type 2A/2B VWD (13.6%) also represented. In comparison, errors in identification of HMW VWF reduced samples only averaged 11.5%, primarily driven by use of insufficient test panels (6.3%) or misinterpretation of results (4.2%) and infrequently analytical errors (1.0%). CONCLUSION: Type 2M VWD is more often misidentified (70.6%) than correctly identified as 2M VWD (29.4%), and potentially explaining the relative under-reported incidence of 2M VWD in the literature.

Aging blunts hyperventilation-induced hypocapnia and reduction in cerebral blood flow velocity during maximal exercise.

Cerebral blood flow (CBF) increases from rest to ∼60% of peak oxygen uptake (VO(2peak)) and thereafter decreases towards baseline due to hyperventilation-induced hypocapnia and subsequent cerebral vasoconstriction. It is unknown what happens to CBF in older adults (OA), who experience a decline in CBF at rest coupled with a blunted ventilatory response during VO(2peak). In 14 OA (71 ± 10 year) and 21 young controls (YA; 23 ± 4 years), we hypothesized that OA would experience less hyperventilation-induced cerebral vasoconstriction and therefore an attenuated reduction in CBF at VO(2peak). Incremental exercise was performed on a cycle ergometer, whilst bilateral middle cerebral artery blood flow velocity (MCA V (mean); transcranial Doppler ultrasound), heart rate (HR; ECG) and end-tidal PCO(2) (P(ET)CO(2)) were monitored continuously. Blood pressure (BP) was monitored intermittently. From rest to 50% of VO(2peak), despite greater elevations in BP in OA, the change in MCA V(mean) was greater in YA compared to OA (28% vs. 15%, respectively; P < 0.0005). In the YA, at intensities >70% of VO(2peak), the hyperventilation-induced declines in both P(ET)CO(2) (14 mmHg (YA) vs. 4 mmHg (OA); P < 0.05) and MCA V(mean) (-21% (YA) vs. -7% (OA); P < 0.0005) were greater in YA compared to OA. Our findings show (1), from rest-to-mild intensity exercise (50% VO(2peak)), elevations in CBF are reduced in OA and (2) age-related declines in hyperventilation during maximal exercise result in less hypocapnic-induced cerebral vasoconstriction.

British Society of Haematology, Slide Session presented at the Annual Scientific Meeting, Brighton 2009.

Seven cases were discussed by an expert panel at the 2009 Annual Scientific Meeting of the British Society of Haematology. These cases are presented in a similar format to that adopted for the meeting. There was an initial discussion of the presenting morphology, generation of differential diagnoses and then, following display of further presenting and diagnostic information, each case was concluded with provision of a final diagnosis.

Laboratory identification of factor VIII inhibitors in the real world: the experience from Australasia.

The laboratory has a key role in the initial detection of factor inhibitors and an ongoing role in the measurement of inhibitor titres during the course of inhibitor eradication therapy. The most commonly seen factor inhibitors are those directed against factor VIII (FVIII), usually detected either using the original or Nijmegen-modified Bethesda assay. In view of previously demonstrated high variability in laboratory results for inhibitor assays, we have more extensively examined laboratory performance in the identification of FVIII inhibitors. Over the past 3 years, we conducted two questionnaire-based surveys and two wet-challenge surveys utilizing eight samples comprising no FVIII inhibitor (n = 1), or low-titre (n = 2), medium-titre (n = 3) or high-titre (n = 2) FVIII inhibitor. Four samples were tested by 42 laboratories in 2007, and four by 52 laboratories in 2009. High inter-laboratory variation was evident, with CVs around 50% not uncommon, and some 10% of all laboratories (or around 15% of laboratories using Bethesda method) failed to detect low-level inhibitors of around 1 BU mL(-1). Laboratories using the Nijmegen method appeared to perform better than those using a standard Bethesda assay, with lower evident assay variation and no false negatives. There was a wide variety of laboratory practice, with no two laboratories using exactly the same process for testing and interpretation of factor inhibitor findings. In conclusion, our study indicates that there is still much need for standardization and improvement in factor inhibitor detection, and we hope that our findings provide a basis for future improvements in this area.

Methodology and outcomes of platelet aggregation testing in Australia, New Zealand and the Asia-Pacific region: results of a survey from the Royal College of Pathologists of Australasia Haematology Quality Assurance Program.

Platelet aggregometry is widely used to investigate platelet function but its performance is poorly standardized between laboratories. The aim of this work was to document the platelet aggregation methods used in specialist laboratories enrolled in the Haematology Quality Assurance Program of the Royal College of Pathologists of Australasia. A questionnaire requesting many details of methodology was distributed and from the responses, we determined a consensus view. Consensus was defined here as >70% agreement among respondents in answer to a question and this was seen for a number of aspects of the preanalytical, analytical and interpretive phases. However, for many questions there was a wide variation in responses. Sixteen laboratories provided a breakdown of the types of abnormal results typically seen in a 12-month period. In these laboratories a total of 1400 patients were tested and 390 (27%) had abnormal platelet function. Although it was common to diagnose the cause as aspirin or an aspirin-like defect or a release/storage pool disorder, the range of experience was wide and other rare defects were reported. We conclude that whilst there are a number of points of agreement between laboratories in platelet function testing, standardization could be improved.

Laboratory diagnosis of von Willebrand's disorder: quality and diagnostic improvements driven by peer review in a multilaboratory test process.

Regular multilaboratory surveys of laboratories derived primarily from Australia, New Zealand and Southeast Asia have been conducted over the past 7 years to evaluate testing proficiency in the diagnosis of von Willebrand's disorder (VWD) and to assess changes to test practice. Participating laboratories (currently 45) are asked to perform their usual panel of tests for VWD, and then to self-interpret test results as to the likelihood (or not) of VWD, as well as to the potential subtype identified. Samples provided in the past two survey distributions (both conducted in 2003) were as follows. Survey part A/distribution 1: Normal donor plasma, plasma with borderline normal/reduced levels of VWF (x2) and plasma from an individual with type 2 A VWD. Survey part B/distribution 2 (family VWD study): Plasma from a father, mother and son with borderline normal/reduced von Willebrand factor (VWF), and a daughter with type 3 VWD. In line with previously published survey results, the interassay and within method coefficients of variation (CV) were similar for all assays (around 15-25%), although tending to be slightly higher for VWF:RCo and VWF:CB than VWF:Ag and FVIII:C. Most laboratories reported test values consistent with expected findings, and made correct interpretations or predictions regarding the nature of the samples, although discrepant assay results or interpretations are still seen in approximately 5-10% of responses (typically from laboratories using a more limited test panel or not performing the VWF:CB). Overall, problems with the non-identification of functional VWF discordance in type 2 VWD, the misidentification of functional VWF discordance in type 1 VWD, and difficulties in discriminating types 1 and 3 VWD appear to predominate. In comparison with previous surveys, performance of electro-immuno diffusion (EID) (or Laurel gel) procedures has now ceased, and a reduction in VWF:RCo and VWF:Multimer testing and an increase in latex immunoassay (LIA) testing is sustained. We conclude that laboratories are generally proficient in tests for VWD, and that diagnostic error rates are reduced when test panels are more comprehensive and include the VWF:CB.

Australasian CD34+ quality assurance program and rationale for the clinical utility of the single-platform method for CD34+ cell enumeration.

BACKGROUND: Enumeration of CD34(+) cells should be accurate and comparable between institutions, particularly when making clinical decisions, evaluating data, and in clinical trials. An Australasian CD34(+) quality assurance program (QAP) has been established to compare CD34(+) cell results and method (Part 1). Unexpected variation in WBCCs led to Part 2 of this report. METHODS: Part 1: Methods reagents and results were evaluated for 12 QAP samples analyzed by 36-43 centers. Part 2: The effects of different anticoagulants on WBCC of 12 peripheral blood samples (PBs) were compared using three cell counters. To test the validity of applying the conclusions to clinical samples, the WBCCs of leukapheresed products and BM harvest were also compared. RESULTS: Part 1: In some samples, WBCCs determined by certain cell-counter groups were significantly different. Results for percentage of CD34(+) and CD34(+)/microL suggest that standardization on the lyse-no-wash and single platform (SP) method reduces variation of results between institutions. Part 2: Using different counters, PB WBCC in ACD-A showed greater variation than the same PB in EDTA. For PB in different anticoagulants, the extent of difference in WBCC for the same PB is dependent on the counter used. DISCUSSION: This CD34 QAP has identified ACD-A as an additional factor that contributes to the disparate WBCCs, which may further compromise the accuracy of CD34(+) cell counts obtained by the dual platform (DP) method, especially for leukapheresed products. In order to achieve greater accuracy within individual institutions, as well as permitting more reliable inter-institutional comparisons, our data supports the adoption of the SP as the standard method for CD34(+) cell enumeration.

Accuracy, reproducibility and clinical utility of the CoaguChek S portable international normalized ratio monitor in an outpatient anticoagulation clinic.

The accuracy and reproducibility of the CoaguChek S, and its clinical agreement with conventional laboratory international normalized ratio (INR) determination, were evaluated in an outpatient anticoagulation clinic setting. Forty-three patients provided 248 paired INR measurements for analysis. The paired results were highly correlated (r = 0.90). The mean coefficient of variation for the CoaguChek S for a random sample of 21 patients with three repeated tests each, was 4%. Clinical applicability was also measured by discrepant INR values, as defined in the literature by expanded and narrow agreement, and by INR values resulting in a different clinical decision by a blinded haematology registrar. Expanded agreement and narrow agreement between the two INR values occurred 90 and 88% of the time, respectively. The stricter criteria set down by the clinician resulted in 73% of paired results producing the same dosage decision. The CoaguChek S displayed good correlation with laboratory determination of INR and compared relatively well with expanded and narrow clinical agreement criteria.

Association between high interleukin-6 levels and adverse outcome after autologous haemopoietic stem cell transplantation.

We studied interleukin-6 (IL-6) levels on the day of transplantation in 31 patients undergoing autologous haemopoietic stem cell transplantation (SCT) (either peripheral blood stem cell transplantation (PBSCT) or bone marrow transplantation (BMT)) for neoplastic diseases to determine if there was a relationship between IL-6 level and rate of haemopoietic recovery, length of stay in hospital, and survival. There was no apparent delay in post-transplant recovery associated with elevated IL-6 levels. However, increased values of IL-6 tended to be associated with an increased length of stay in hospital (P = 0.083). There was a highly significant adverse association between higher IL-6 levels and survival following transplantation (P = 0.0001). This association remained significant (P = 0.013) in the uniform subgroup of patients with malignant lymphoma with chemosensitive disease who had undergone BMT (that is, excluding patients who had undergone PBSCT) (n = 13). Knowledge of IL-6 levels on the day of transplant has the potential to provide valuable prognostic information in patients undergoing autologous haemopoietic SCT.

Pathologic splenic rupture as the presentation of mantle cell lymphoma.

Pathologic splenic rupture in non-Hodgkin's lymphoma (NHL) is a rare event, with 32 cases previously reported. Initial presentation of NHL with this complication is even rarer. We report such a case in an 80-year-old man with mantle cell lymphoma (MCL). It is notable that of the previously reported cases of pathologic rupture, three have occurred in MCL, suggesting that patients with this uncommon subtype of NHL may be particularly vulnerable to pathologic splenic rupture. Following splenectomy the patient's disease behaved in a high-grade fashion. Despite an initially encouraging response, his disease ran an aggressive course and he succumbed within four months. This case demonstrates the presentation of MCL with pathologic splenic rupture, as well as the potentially highly malignant behaviour of the disease.

The effect of G-CSF on the composition of human bone marrow.

The effects on bone marrow cellularity and morphology of 6 days' treatment with granulocyte colony-stimulating factor (G-CSF) in 35 patients were studied. Examination of trephine biopsies showed a highly significant increase in cellularity (P < 10-13). Assessment of aspirates revealed an increase in the myeloid to erythroid (M : E) ratio (P = 0.00006), the proportion of myeloid cells (P < 10-8), myelocytes (P = 0.00007), metamyelocytes (P = 0.04), band forms (P = 0.0005) and neutrophils (P = 0.02). This study presents a comprehensive analysis of the effects of six days' administration of G-CSF on human bone marrow.

Hemopoietic stem-cell harvesting and transplantation using G-CSF-primed BM: comparison with unprimed BM and G-CSF-primed PBSC.

BACKGROUND: PBSC collected following G-CSF priming lead to more rapid hemopoietic reconstitution (HR) after autologous transplantation than do unprimed BMstem cells. However, PBSC have a number of disadvantages compared with BM cells, including the need for an extended collection period and requirement for good venous access. METHODS: We retrospectively analysed our experience with an alternative source of hemopoietic stem cells, G-CSF primed BM. Fortyfour patients who underwent BM harvesting after 6 days' administration of G-CSF, at a dose of 5 microg/kg per day, were compared with an equal number who underwent standard (unprimed) BM harvesting. We also analysed HR after autologous transplantation in 16 patients who received unprimed BM, 18 who received G-CSF-primed BM and 14 who received PBSC. RESULTS: G-CSF-primed BM was collected more quickly (p<0.00005) and yielded a larger number of cells (p<0.0001) than unprimed BM. Consequently, larger numbers of cells were available for administration following transplantation with G-CSF-primed BM. The results of HR after transplantation with G-CSF primed BM were intermediate between those of unprimed BM and PBSC. For example, platelet independence (unsupported platelet count > or = 20 2 10(9)/L) occurred after 22 days with unprimed BM, 14 days with G-CSF-printed BM and 10 days with PBSC (p for trend <0.0001) and the mean number of days when platelet transfusions were given was 10, 6 and 3 respectively (p for trend <0.005). These results reflected transplant cell doses. CONCLUSION: G-CSF-primed BM is a valuable source of hemopoietic stem cells for autologous transplantation and a useful alternative to PBSC to certain circumstances.

Fluconazole resistance associated with drug efflux and increased transcription of a drug transporter gene, PDH1, in Candida glabrata.

Sequential Candida glabrata isolates were obtained from the mouth of a patient infected with human immunodeficiency virus type 1 who was receiving high doses of fluconazole for oropharyngeal thrush. Fluconazole-susceptible colonies were replaced by resistant colonies that exhibited both increased fluconazole efflux and increased transcripts of a gene which codes for a protein with 72.5% identity to Pdr5p, an ABC multidrug transporter in Saccharomyces cerevisiae. The deduced protein had a molecular mass of 175 kDa and was composed of two homologous halves, each with six putative transmembrane domains and highly conserved sequences of ATP-binding domains. When the earliest and most azole-susceptible isolate of C. glabrata from this patient was exposed to fluconazole, increased transcripts of the PDR5 homolog appeared, linking azole exposure to regulation of this gene.

Heartstart Scotland: the use of paramedic skills in out of hospital resuscitation.

OBJECTIVE: To assess the frequency with which paramedic skills were used in out of hospital cardiac arrest and the effect of tracheal intubation on outcome. DESIGN: Retrospective analysis of ambulance service reports and hospital records. SETTING: Scottish Ambulance Service and hospitals admitting acute patients throughout Scotland. RESULTS: A total of 8651 out of hospital resuscitation attempts were recorded and tracheal intubation was attempted in 3427 (39.6%) arrests. One hundred and thirty six patients (3.7%) were intubated and 476 (9.1%) of the patients who were not intubated survived to hospital discharge (p < 0.001). Among the patients who were defibrillated the proportion intubated was highest in the patients who received the greatest number of shocks (p < 0.01). Among subjects receiving similar numbers of shocks survival rates were lower for intubated patients (p < 0.01). Patients with unwitnessed arrests were most frequently intubated and survival rates were lowest in this group. CONCLUSIONS: Patients who are intubated seem to have lower survival rates. This may however reflect the difficulty of the resuscitation attempt rather than the effects of intubation. The use of basic life support skills rapidly after cardiac arrest is associated with the best survival rates.

Myelodysplastic syndromes.

The myelodysplastic syndromes (MDS) are a group of clonal disorders, common especially in the elderly, characterised by cytopenias and dysfunctional blood cells. They are a cause of significant morbidity and premature mortality. The cause is not known in most cases. Predisposing factors that have been identified include cytotoxic chemotherapy, benzene and other environmental mutagens, and bone marrow transplantation. Clinically patients present with effects of deficiency of erythrocytes, neutrophils and/or platelets or the diagnosis may be made unexpectedly after routine blood testing. The bone marrow is generally hypercellular and often disorganized; abnormal in vitro cell growth is common. Non-random cytogenetic abnormalities are characteristic and helpful diagnostically; certain subtypes are associated with specific clinical and cytological features. Especially noteworthy are the 5q- and 7-syndromes. The outlook generally is poor. Death comes about from transformation to acute myeloid leukemia (AML), from the complications of cytopenias, or from intercurrent illness. Treatment is unsatisfactory except in young patients who can undergo allografting. Treatments of uncertain value include intensive or gentle chemotherapy. Of the cytokines erythropoietin and granulocyte-macrophage colony-stimulating factor (GM-CSF) so far seem the most promising. However, for the majority management is limited to provision of appropriate supportive care.