Preferred and actual place of death in haematological malignancies: a report from the UK haematological malignancy research network

OBJECTIVES

Hospital death is comparatively common in people with haematological cancers, but little is known about patient preferences. This study investigated actual and preferred place of death, concurrence between these and characteristics of preferred place discussions.

METHODS

Set within a population-based haematological malignancy patient cohort, adults (≥18 years) diagnosed 2004-2012 who died 2011-2012 were included (n=963). Data were obtained via routine linkages (date, place and cause of death) and abstraction of hospital records (diagnosis, demographics, preferred place discussions). Logistic regression investigated associations between patient and clinical factors and place of death, and factors associated with the likelihood of having a preferred place discussion.

RESULTS

Of 892 patients (92.6%) alive 2 weeks after diagnosis, 58.0% subsequently died in hospital (home, 20.0%; care home, 11.9%; hospice, 10.2%). A preferred place discussion was documented for 453 patients (50.8%). Discussions were more likely in women (p=0.003), those referred to specialist palliative care (p<0.001), and where cause of death was haematological cancer (p<0.001); and less likely in those living in deprived areas (p=0.005). Patients with a discussion were significantly (p<0.05) less likely to die in hospital. Last recorded preferences were: home (40.6%), hospice (18.1%), hospital (17.7%) and care home (14.1%); two-thirds died in their final preferred place. Multiple discussions occurred for 58.3% of the 453, with preferences varying by proximity to death and participants in the discussion.

CONCLUSION

Challenges remain in ensuring that patients are supported to have meaningful end-of-life discussions, with healthcare services that are able to respond to changing decisions over time.

The Discovery of 7-Methyl-2-[(7-methyl[1,2,4]triazolo[1,5-a]pyridin-6-yl)amino]-9-(tetrahydro-2H-pyran-4-yl)-7,9-dihydro-8H-purin-8-one (AZD7648), a Potent and Selective DNA-Dependent Protein Kinase (DNA-PK) Inhibitor

DNA-PK is a key component within the DNA damage response, as it is responsible for recognizing and repairing double-strand DNA breaks (DSBs) via non-homologous end joining. Historically it has been challenging to identify inhibitors of the DNA-PK catalytic subunit (DNA-PKcs) with good selectivity versus the structurally related PI3 (lipid) and PI3K-related protein kinases. We screened our corporate collection for DNA-PKcs inhibitors with good PI3 kinase selectivity, identifying compound 1. Optimization focused on further improving selectivity while improving physical and pharmacokinetic properties, notably co-optimization of permeability and metabolic stability, to identify compound 16 (AZD7648). Compound 16 had no significant off-target activity in the protein kinome and only weak activity versus PI3Kα/γ lipid kinases. Monotherapy activity in murine xenograft models was observed, and regressions were observed when combined with inducers of DSBs (doxorubicin or irradiation) or PARP inhibition (olaparib). These data support progression into clinical studies (NCT03907969).

Perspectives of bereaved relatives of patients with haematological malignancies concerning preferred place of care and death: A qualitative study

BACKGROUND

People with haematological malignancies have different end-of-life care patterns from those with other cancers and are more likely to die in hospital. Little is known about patient and relative preferences at this time and whether these are achieved.

AIM

To explore the experiences and reflections of bereaved relatives of patients with leukaemia, lymphoma or myeloma, and examine (1) preferred place of care and death; (2) perceptions of factors influencing attainment of preferences; and (3) changes that could promote achievement of preferences.

DESIGN

Qualitative interview study incorporating 'Framework' analysis.

SETTING/PARTICIPANTS

A total of 10 in-depth interviews with bereaved relatives.

RESULTS

Although most people expressed a preference for home death, not all attained this. The influencing factors include disease characteristics (potential for sudden deterioration and death), the occurrence and timing of discussions (treatment cessation, prognosis, place of care/death), family networks (willingness/ability of relatives to provide care, knowledge about services, confidence to advocate) and resource availability (clinical care, hospice beds/policies). Preferences were described as changing over time and some family members retrospectively came to consider hospital as the 'right' place for the patient to have died. Others shared strong preferences with patients for home death and acted to ensure this was achieved. No patients died in a hospice, and relatives identified barriers to death in this setting.

CONCLUSION

Preferences were not always achieved due to a series of complex, interrelated factors, some amenable to change and others less so. Death in hospital may be preferred and appropriate, or considered the best option in hindsight.

Palliative care specialists' perceptions concerning referral of haematology patients to their services: findings from a qualitative study

BACKGROUND

Haematological malignancies (leukaemias, lymphomas and myeloma) are complex cancers that are relatively common, affect all ages and have divergent outcomes. Although the symptom burden of these diseases is comparable to other cancers, patients do not access specialist palliative care (SPC) services as often as those with other cancers. To determine the reasons for this, we asked SPC practitioners about their perspectives regarding the barriers and facilitators influencing haematology patient referrals.

METHODS

We conducted a qualitative study, set within the United Kingdom's (UK's) Haematological Malignancy Research Network (HMRN: www.hmrn.org ), a population-based cohort in the North of England. In-depth, semi-structured interviews were conducted with 20 SPC doctors and nurses working in hospital, community and hospice settings between 2012 and 2014. Interviews were digitally audio-recorded, transcribed and analysed for thematic content using the 'Framework' method.

RESULTS

Study participants identified a range of barriers and facilitators influencing the referral of patients with haematological malignancies to SPC services. Barriers included: the characteristics and pathways of haematological malignancies; the close patient/haematology team relationship; lack of role clarity; late end of life discussions and SPC referrals; policy issues; and organisational issues. The main facilitators identified were: establishment of inter-disciplinary working patterns (co-working) and enhanced understanding of roles; timely discussions with patients and early SPC referral; access to information platforms able to support information sharing; and use of indicators to 'flag' patients' needs for SPC. Collaboration between haematology and SPC was perceived as beneficial and desirable, and was said to be increasing over time.

CONCLUSIONS

This is the first UK study to explore SPC practitioners' perceptions concerning haematology patient referrals. Numerous factors were found to influence the likelihood of referral, some of which related to the organisation and delivery of SPC services, so were amenable to change, and others relating to the complex and unique characteristics and pathways of haematological cancers. Further research is needed to assess the extent to which palliative care is provided by haematology doctors and nurses and other generalists and ways in which clinical uncertainty could be used as a trigger, rather than a barrier, to referral.

Discovery of Pyrazolo[1,5-a]pyrimidine B-Cell Lymphoma 6 (BCL6) Binders and Optimization to High Affinity Macrocyclic Inhibitors

Inhibition of the protein-protein interaction between B-cell lymphoma 6 (BCL6) and corepressors has been implicated as a therapeutic target in diffuse large B-cell lymphoma (DLBCL) cancers and profiling of potent and selective BCL6 inhibitors are critical to test this hypothesis. We identified a pyrazolo[1,5-a]pyrimidine series of BCL6 binders from a fragment screen in parallel with a virtual screen. Using structure-based drug design, binding affinity was increased 100000-fold. This involved displacing crystallographic water, forming new ligand-protein interactions and a macrocyclization to favor the bioactive conformation of the ligands. Optimization for slow off-rate constant kinetics was conducted as well as improving selectivity against an off-target kinase, CK2. Potency in a cellular BCL6 assay was further optimized to afford highly selective probe molecules. Only weak antiproliferative effects were observed across a number of DLBCL lines and a multiple myeloma cell line without a clear relationship to BCL6 potency. As a result, we conclude that the BCL6 hypothesis in DLBCL cancer remains unproven.

Variations in specialist palliative care referrals: findings from a population-based patient cohort of acute myeloid leukaemia, diffuse large B-cell lymphoma and myeloma

Objective

To develop and implement a methodology for capturing complete haematological malignancy pathway data and use it to identify variations in specialist palliative care (SPC) referrals.

Methods

In our established UK population-based patient cohort, 323 patients were diagnosed with acute myeloid leukaemia, diffuse large B-cell lymphoma or myeloma between May 2005 and April 2008, and died before April 2010. A day-by-day calendar approach was devised to collect pathway data, including SPC referrals, to supplement routinely collected information on clinical presentation, diagnosis, treatment, response, and date and place of death.

Results

155 (47.9%) of the 323 patients had at least one SPC referral. The likelihood of referral increased with survival (OR 6.58, 95% CIs 3.32 to 13.03 for patients surviving ≥1 year compared to ≤1 month from diagnosis), and varied with diagnosis (OR 1.96, CIs 1.15 to 3.35 for myeloma compared to acute myeloid leukaemia). Compared to patients dying in hospital, those who died at home or in a hospice were also more likely to have had an SPC referral (OR 3.07, CIs 1.59 to 5.93 and 4.74, CIs 1.51 to 14.81, respectively). No associations were found for age and sex.

Conclusions

Our novel approach efficiently captured pathway data and SPC referrals, revealing evidence of greater integration between haematology and SPC services than previously reported. The likelihood of referral was much higher among those dying outside hospital, and variations in practice were observed by diagnosis, emphasising the importance of examining diseases individually.

Place of death in haematological malignancy: variations by disease sub-type and time from diagnosis to death

BACKGROUND

The reasons patients with haematological malignancies die in hospital more often than those with other cancers is the subject of much speculation. We examined variations in place of death by disease sub-type and time from diagnosis to death, to identify groups of 'at-risk' patients.

METHODS

The study is based in the United Kingdom within the infrastructure of the Haematological Malignancy Research Network (HMRN), a large on-going population-based cohort including all patients newly diagnosed with haematological malignancies in the north of England. Diagnostic, demographic, prognostic, treatment and outcome data are collected for each patient and individuals are 'flagged' for death. This study includes all adults (≥18 years) diagnosed 1st September 2004 to 31st August 2010 (n = 10,325), focussing on those who died on/before 31st August 2012 (n = 4829).

RESULTS

Most deaths occurred in hospital (65.9%), followed by home (15.6%), nursing home (11%) and hospice (7.5%) and there was little variation by diagnostic sub-type overall. Differences in place of death were, however, observed by time from diagnosis to death, and this was closely related to sub-type; 87.7% of deaths within a month of diagnosis happened in hospital and these largely occurred in patients with acute myeloid leukaemia, diffuse large B-cell lymphoma and myeloma. Patients surviving longer, and particularly beyond 1 year, were less likely to die in hospital and this corresponded with an increase in the proportion of home deaths.

CONCLUSIONS

Time from diagnosis to death was clearly a major determinant of place of death and many patients that died within three months of diagnosis did so in hospital. This was closely related to disease sub-type, with early deaths occurring most notable in the more aggressive diseases. This is likely to be due to a combination of factors including acute presentation, rapid disease progression without transition to a palliative approach to care and complications of treatment. Nonetheless, hospital deaths also occurred frequently in indolent diseases, suggesting that other factors were likely to contribute to the large proportion of hospital deaths overall. More evidence is needed to fully understand these complex cancers.

Haematological malignancy: are patients appropriately referred for specialist palliative and hospice care? A systematic review and meta-analysis of published data

Haematological malignancies are complex diseases, affecting the entire age spectrum, and having marked differences in presentation, treatment, progression and outcome. Patients have a significant symptom burden and despite treatment improvements for some sub-types, many patients die from their disease. We carried out a systematic review and meta-analysis to examine the proportion of patients with haematological malignancies that received any form of specialist palliative or hospice care. Twenty-four studies were identified, nine of which were suitable for inclusion in the meta-analysis. Our review showed that patients with haematological malignancies were far less likely to receive care from specialist palliative or hospice services compared to other cancers (Risk Ratio 0.46, [95% confidence intervals 0.42-0.50]). There are several possible explanations for this finding, including: ongoing management by the haematology team and consequent strong bonds between staff and patients; uncertain transitions to a palliative approach to care; and sudden transitions, leaving little time for palliative input. Further research is needed to explore: transitions to palliative care; potential unmet patient needs; where patients want to be cared for and die; existing practices in the delivery of palliative and end-of-life care; and barriers to specialist palliative care and hospice referral and how these might be overcome.

Destined to die in hospital? Systematic review and meta-analysis of place of death in haematological malignancy

Background

Haematological malignancies are a common, heterogeneous and complex group of diseases that are often associated with poor outcomes despite intensive treatment. Research surrounding end-of-life issues, and particularly place of death, is therefore of paramount importance, yet place of death has not been formally reviewed in these patients.

Methods

A systematic literature review and meta-analysis was undertaken using PubMed to identify all studies published between 1966 and 2010. Studies examining place of death in adult haematology patients, using routinely compiled morbidity and mortality data and providing results specific to this disease were included. 21 studies were identified with descriptive and/or risk-estimate data; 17 were included in a meta-analysis.

Results

Compared to other cancer deaths, haematology patients were more than twice as likely to die in hospital (Odds Ratio 2.25 [95% Confidence Intervals, 2.07-2.44]).

Conclusion

Home is generally considered the preferred place of death but haematology patients usually die in hospital. This has implications for patients who may not be dying where they wish, and also health commissioners who may be funding costly end-of-life care in inappropriate acute hospital settings. More research is needed about preferred place of care for haematology patients, reasons for hospital deaths, and how these can be avoided if home death is preferred.

SNARE-dependent glutamate release in megakaryocytes

Objective

The identification of signaling pathways involved in megakaryocytopoiesis is essential for development of novel therapeutics to treat hematological disorders. Following our previous findings that megakaryocytes express functional channel-forming N-methyl-D-aspartate-type glutamate receptors, here we aimed to determine the glutamate release capacity in undifferentiated and differentiated megakaryocytes and the role of soluble N-ethyl maleimide-sensitive factor attachment protein receptor (SNARE) proteins that are known to be associated with vesicular exocytosis.

Materials and Methods

Using the megakaryocytic cell line MEG-01, primary megakaryocytes, and tissue sections of bone marrow, reverse transcription polymerase chain reaction, Western blot analysis, and immunolocalization were employed to detect factors required for vesicular glutamate release. Vesicle recycling was monitored by acridine orange and FM1-43 staining and glutamate release activity was assessed by an enzyme-linked fluorimetric assay. Genetically modified MEG-01 cells, with deletion or overexpression of SNARE and vesicular proteins, were also examined for glutamate release activity.

Results

We demonstrated that megakaryocytes express numerous proteins required for vesicular glutamate release, including core SNARE proteins, vesicle-associated membrane protein, soluble N-ethyl maleimide-sensitive factor attachment protein−23, and syntaxin, as well as specific glutamate-loading vesicle proteins, VGLUT1 and VGLUT2. Moreover, active vesicle recycling and differentiation-dependent glutamate release were observed in megakaryocytes. Vesicle-associated membrane protein−deficient MEG-01 cells, which are impaired in vesicle recycling, showed a 30% decrease in released glutamate, whereas overexpression of VGLUT1 exhibited up to a 2.2-fold increase in glutamate release.

Conclusion

These data show that glutamate release from megakaryocytes occurs in a SNARE-dependent, exocytotic manner and is increased during differentiation, suggesting that manipulation of glutamate signaling could influence megakaryocytopoiesis and, therefore, offer a suitable target for the treatment of thrombosis and other hematological disorders.

Delayed appearance of markers of intravascular haemolysis in a case of paroxysmal cold haemoglobinuria

The aetiology of haemolytic disease is diverse and the diagnosis often relies on laboratory testing. We describe a case of intravascular haemolysis, which illustrates that significant intravascular haemolysis can occur in the absence of any abnormal haematological findings. Despite gross haemoglobinuria at presentation, the haemoglobin and reticulocyte counts were both within reference limits and a normal blood film was observed. Subsequently, acute tubular necrosis occurred secondary to haemolysis, and acute renal failure was evident by day 2. However, the haemoglobin decreased slowly reaching a nadir of 75 g/L on day 6 (reference interval 130-180 g/L). A diagnosis of paroxysmal cold haemoglobinuria secondary to mycoplasma infection was subsequently made. Biochemical analysis was useful in this case to confirm that the gross pigmentation in the samples received could be attributable to intravascular haemolysis.

Mechanical stimulation induces preprotachykinin gene expression in osteoarthritic chondrocytes which is correlated with modulation of the transcription factor neuron restrictive silence factor

We have previously demonstrated that the transcription factor termed neuron restrictive silencer factor (NRSF) and the truncated splice variant, NRSF short form (sNRSF) are major modulators of preprotachykinin A (TAC1) gene expression. In this communication we addressed whether TAC1 gene expression would be effected in response to mechanical stimulation of both normal and osteoarthritic (OA) chondrocytes. Chondrocytes were mechanically stimulated for 20 min, and then incubated under normal tissue culture conditions for 1 or 3h. RT-PCR and quantitative PCR (qPCR) were used to investigate expression of TAC1, NRSF and sNRSF mRNA at these time points. Western blotting was used to validate and confirm expression of sNRSF protein in chondrocytes in response to mechanical stimulation. We observed that TAC1 was expressed in normal chondrocytes, with no evidence of NRSF or sNRSF expression. TAC1 mRNA expression did not significantly change following mechanical stimulation in normal cells. OA chondrocytes expressed TAC1 and sNRSF mRNA, though not NRSF, and following mechanical stimulation there was a significant upregulation of both TAC1 and sNRSF mRNA, which returned to baseline levels 3h post-stimulation. sNRSF protein was upregulated at 1 and 2h following stimulation of OA chondrocytes. In summary, differential expression of TAC1 and sNRSF in OA chondrocytes associates their expression with the disease. The change in expression of sNRSF and TAC1 mRNA following mechanical stimulation in OA but not normal chondrocytes suggests that sNRSF may be involved in the regulation of SP production in OA cartilage. These differences between normal and OA mechanotransduction responses may be important in the production of phenotypic changes present in diseased cartilage.

Regulation and role of REST and REST4 variants in modulation of gene expression in in vivo and in vitro in epilepsy models

Repressor element-1 silencing transcription factor (REST) is a candidate modulator of gene expression during status epilepticus in the rodent. In such models, full-length REST and the truncated REST4 variant are induced and can potentially direct differential gene expression patterns. We have addressed the regulation of these REST variants in rodent hippocampal seizure models and correlated this with expression of the proconvulsant, substance P encoding, PPT-A gene. REST and REST4 were differentially regulated following kainic acid stimulus both in in vitro and in vivo models. REST4 was more tightly regulated than REST in both models and its transient expression correlated with that of the differential regulation of PPT-A. Consistent with this, overexpression of a truncated REST protein (HZ4, lacking the C-terminal repression domain) increased expression of the endogenous PPT-A gene. Similarly the proximal PPT-A promoter reporter gene construct was differentially regulated by the distinct REST isoforms in hippocampal cells with HZ4 being the major inducer of increased reporter expression. Furthermore, REST and REST4 proteins were differentially expressed and compartmentalized within rat hippocampal cells in vitro following noxious stimuli. This differential localization of the REST isoforms was confirmed in the CA1 region following perforant path and kainic acid induction of status epilepticus in vivo. We propose that the interplay between REST and REST4 alter the expression of proconvulsant genes, as exemplified by the PPT-A gene, and may therefore regulate the progression of epileptogenesis.

The development of targeted chemotherapy for CNS lymphoma?a pilot study of the IDARAM regimen

PURPOSE

We have developed and evaluated a CNS-targeted chemotherapy regimen based on the pharmacokinetic properties of the individual drugs in the combination.

PATIENTS AND METHODS

In a twin-track study, 16 patients with secondary CNS lymphoma (SCNSL) and 8 with primary CNS lymphoma (PCNSL) were treated with IDARAM which comprised idarubicin 10 mg/m(2) i.v., days 1 and 2; dexamethasone 100 mg, 12-h infusion, days 1, 2 and 3; cytosine arabinoside (ARA-C) 1.0 g/m(2), 1-h infusion, days 1 and 2; methotrexate 2.0 g/m(2), 6-h infusion, day 3 (with folinic acid rescue); and cytosine arabinoside 70 mg plus methotrexate 12 mg, intrathecally, days 1 and 8. Two cycles were delivered at 3-weekly intervals. After response assessment, patients received adjuvant cranial radiotherapy (40 Gy over 20 fractions).

RESULTS

The series comprised 24 patients, 11 male and 13 female. Their median age was 53 years (range 21 to 73 years). Grade 4 neutropenia and thrombocytopenia occurred in the majority of patients treated. Of the eight PCNSL patients, seven achieved complete remission (CR). Four remained in CR at the time of this report with a median duration of follow-up of 25 months (range 11 to 42 months). Of the 16 SCNSL patients, 12 achieved CR. Seven patients remained in CR at the time of this report with a median duration of follow-up of 24 months (range 18 to 57 months).

CONCLUSION

This study suggests that IDARAM is an effective regimen in both PCNSL and SCNSL and is suitable for further development and evaluation.

No barrier to diffusion between cell soma and neurite membranes in sympathetic neurons for a GPI-anchored glycoprotein

As neurons extend their axons, it is thought that newly synthesised membrane components travel in vesicles along the axon, fuse with the growth cone membrane, and diffuse back along the axonal membrane. However, it is difficult to explain how axons continue to be populated with membrane proteins as they extend in length. To investigate this problem, we have used a CEPU-green fluorescent protein (GFP) chimeric protein to study the site of insertion of new glycosyl phosphatidyl inositol (GPI)-anchored glycoproteins and their subsequent behaviour in chick dorsal root ganglia (DRG) neurons. Infection of cultures grown for 24 h revealed rapid expression of CEPU-GFP over the whole surface of the neuron, more rapidly than could be accounted for by diffusion from the growth cone, and fluorescence intensity was uniform along the length of the neurite. Photobleaching experiments of neurite membrane revealed that recovery of fluorescence was due to diffusion from adjacent membranes and there was no evidence for membrane flow in either direction. Photobleaching of membrane adjacent to the cell body also showed rapid recovery, with chimera diffusing both from cell body membrane and the distal neurite membrane into the bleached area. These results suggest there is no barrier to diffusion between the cell body and neurite membrane in DRG and sympathetic neurons cultured for 1 or 2 days in vitro. We propose that the neurite is populated by newly synthesised chimera by diffusion from both regions. This situation may also occur in neurons in the early stages of extending axons in vivo prior to polarisation and the development of the dendritic field.

Clinically significant newly presenting autoimmune thrombocytopenic purpura in adults: a prospective study of a population-based cohort of 245 patients

The true incidence and prognosis of autoimmune thrombocytopenic purpura (ITP) in adults is unknown. We present the results of a prospective study in a population-based cohort of newly presenting adults (> or = 16 years) with ITP and platelet count of < 50 x 109/l, which took place between 1 January 1993 and 31 December 1999 in the former Northern Health Region in the UK (population 3.08 million). A total of 245 cases were confirmed by bone marrow examination with a median follow-up of 60 months (range 6-78 months). There were 134 females/111 males (1.2:1). Overall incidence was 1.6 per 105 per annum. Absolute incidence was similar for both sexes, with highest age-specific incidence in those aged > 60 years. Thirty patients (12%) presented with frank bleeding, and 28% were asymptomatic. Forty-five patients (18%) received no treatment, and 135 (55%) received first-line treatment only. Thirty patients (12%) underwent splenectomy. There were four deaths (1.6%) from bleeding and/or the complications of therapy in this cohort, but only one was in the acute phase of the illness. The majority of patients (155 out of 245) achieved remission (platelet count > 100 x 109/l), with a further 59 (24%) in partial remission with no symptoms (platelet count 30-100 x 109/l). This population-based study suggests that the traditional view of adult ITP as being a predominantly chronic disease that preferentially affects females needs to be modified.

NMDA receptor-mediated regulation of human megakaryocytopoiesis

Identification of the regulatory inputs that direct megakaryocytopoiesis and platelet production is essential for the development of novel therapeutic strategies for the treatment of thrombosis and related hematologic disorders. We have previously shown that primary human megakaryocytes express the N-methyl-d-aspartate acid (NMDA) receptor 1 (NR1) subunit of NMDA-type glutamate receptors, which appear to be pharmacologically similar to those identified at neuronal synapses, responsible for mediating excitatory neurotransmission in the central nervous system. However, the functional role of NMDA receptor signaling in megakaryocytopoiesis remains unclear. Here we provide evidence that demonstrates the fundamental importance of this signaling pathway during human megakaryocyte maturation in vitro. Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis of RNA extracted from CD34+-derived megakaryocytes identified expression of NR2A and NR2D receptor subunits in these cells, as well as the NMDA receptor accessory proteins, Yotiao and postsynaptic density protein 95 (PSD-95). In functional studies, addition of a selective NMDA receptor antagonist, MK-801 inhibited proplatelet formation, without affecting proliferation or apoptosis. Exposure of CD34+ cells to MK-801 cultured for 14 days in the presence of thrombopoietin induced a decrease in expression of the megakaryocyte cell surface markers CD61, CD41a, and CD42a compared with controls. At an ultrastructural level, MK-801-treated cells lacked alpha-granules, demarcated membranes, and multilobed nuclei, which were prominent in untreated mature megakaryocyte controls. Using immunohistochemistry on sections of whole tibiae from c-Mpl knockout mice we demonstrated that megakaryocytic NMDA receptor expression was maintained following c-Mpl ablation. These data support a fundamental role for glutamate signaling in megakaryocytopoiesis and platelet production, which is likely to be independent of thrombopoietin-mediated effects.

A prospective study of the prevalence of undiagnosed coeliac disease in laboratory defined iron and folate deficiency

AIMS

To determine the prevalence of coeliac disease in a group of patients in the community who have been shown in the laboratory to have iron and/or folate deficiency. To assess the cost efficiency of this laboratory based case finding strategy.

METHODS

The study was undertaken in a large general hospital in the UK serving a population of 300 000. Three hundred and thirty three eligible patients with iron and/or folate deficiency were identified and contacted over an 18 month period. Case finding was by testing for coeliac disease using serological methods and subsequent histological confirmation.

RESULTS

Of the 333 eligible and contactable patients with iron and/or folate deficiency, 258 (77%) consented to coeliac disease antibody testing. Twenty eight patients (10.9%) were positive for coeliac disease antibodies. Of these, 24 patients proceeded to endoscopy and biopsy, resulting in 12 cases of histologically confirmed coeliac disease (4.7% (95% confidence interval, 2.1% to 6.8%) of patients tested for coeliac disease antibodies).

CONCLUSIONS

This laboratory based methodology detected a considerable number of new coeliac disease cases in the community. Many of these patients did not present with clinical findings suggestive of malabsorption and might not otherwise have been diagnosed. Laboratory based methodologies should be considered in conjunction with other strategies for the early identification and treatment of coeliac disease.

High-level expression of recombinant Fc chimeric proteins in suspension cultures of stably transfected J558L cells

Recombinant Fc chimeric proteins are useful tools for studying protein function, including the analysis of molecular interactions by techniques such as expression cloning. Here we describe a method we have used to express the IgLON family proteins, CEPU1 and OBCAM, as recombinant Fc chimeric proteins in stably transfected mouse J558L myeloma cells. The use of this cell line provided the opportunity to maximize protein production, as it secretes antibodies in large quantities and can be grown to high density in small volumes of culture medium. Isolation of recombinant OBCAMFc from the adherent COS7 cell line suggested a minimum level of expression of 0.07 mg OBCAMFc/100 mL culture medium, while the J558L cell line expressed OBCAMFc at approximately 11.4 mg/100 mL culture medium. Purification of IgLON-Fc expressed by J558L cells was simpler than purification from COS7 cells because of the lower volume of culture medium generated. Furthermore, contamination of J558L expressed IgLONFc with bovine IgG from the culture medium was negligible. The method presented, which utilizes a commercially available small-scale bioreactor, provides the nonspecialist protein expression laboratory with the means to produce recombinant proteins quickly and easily in milligram quantities.

Identification and characterization of CEPU-Se-A secreted isoform of the IgLON family protein, CEPU-1

CEPU-1/Neurotrimin is a neuronal glycoprotein thought to play a role in axon guidance and cell-cell recognition. It is a member of the IgLON family, has three C2 domains, and is attached to the plasma membrane by a GPI-anchor. We report here the characterisation of an alternatively-spliced isoform of CEPU-1 that is secreted. This isoform, termed CEPU-Se, is coexpressed with CEPU-1 in retina, cerebellum, and DRG neurons. In the cerebellum CEPU-1/CEPU-Se is expressed predominantly on granule cells and in the molecular layer. Divalent but not monovalent CEPU-Se interacts with CEPU-1 and other IgLONs, suggesting that the ability of CEPU-Se to modify the activity of the IgLON family may require an additional cofactor. CEPU-Se does not support the outgrowth of DRG neurons or the extension of established growth cones; however, neurite outgrowth on laminin is unaffected by CEPU-Se. Our data suggest that CEPU-Se may act to modulate the ability of CEPU-1, LAMP, and OBCAM to influence neurite outgrowth.

Co-localisation, heterophilic interactions and regulated expression of IgLON family proteins in the chick nervous system

The chick glycoprotein GP55 has been shown to inhibit the growth and adhesion of DRG and forebrain neurons. GP55 consists of several members of the IgLON family, a group of glycoproteins including LAMP, OBCAM, CEPU-1 (chick)/neurotrimin (rat) and neurotractin (chick)/kilon (rat) thought to play a role in the guidance of growing axons. IgLONs belong to the Ig superfamily and have three C2 domains and a glycosyl phosphatidylinositol anchor which tethers them to the neuronal plasma membrane. We have now completed the deduced amino acid sequence for two isoforms of chicken OBCAM and used recombinant LAMP, OBCAM and CEPU-1 to raise antisera specific to these three IgLONs. LAMP and CEPU-1 are co-expressed on DRG and sympathetic neurons, while both overlapping and distinct expression patterns for LAMP, OBCAM and CEPU-1 are observed in retina. Analysis of IgLON mRNA expression reveals that alternatively spliced forms of LAMP and CEPU-1 are developmentally regulated. In an attempt to understand how the IgLONs function, we have begun to characterise their molecular interactions. LAMP and CEPU-1 have already been shown to interact homophilically. We now confirm that OBCAM will bind homophilically and also that LAMP, OBCAM and CEPU-1 will interact heterophilically with each other. We propose that IgLON activity will depend on the complement of IgLONs expressed by each neuron.

Herpesvirus infection of eye and brain in HIV infected patients

OBJECTIVES

To compare histological with genome detection methods for diagnosis of herpesvirus infection in eye and brain of HIV infected patients undergoing necropsy and to correlate these findings with both antemortem clinical findings and postmortem evidence of extraocular herpesvirus infection, especially in the CNS.

METHODS

A prospective study of 31 consecutive HIV infected patients undergoing necropsy. In life 11 patients had been assessed by an ophthalmologist because of ocular symptoms. Ocular and brain samples were examined for herpesviruses by conventional histological methods and by nested polymerase chain reaction (nPCR) for all eight human herpesviruses; evidence of extraneural herpesvirus infection was sought by histological methods.

RESULTS

Although only 12 out of 31 patients (39%) had antemortem clinical evidence of ocular or CNS herpesvirus associated disease, herpesviruses were detected by nPCR in eye and brain from 26 (84%) patients; six patients had more than one herpesvirus infection. There was concordance between ocular and CNS findings in 15 of 19 patients (79%) with CMV infection. 17 of 31 patients (55%) had extraocular or CNS CMV infection at necropsy. Genome detection using nPCR was superior to histological methods for diagnosis of ocular and CNS herpesvirus infection.

CONCLUSION

Herpesvirus infection of eye and brain was a frequent finding at necropsy in this group of HIV infected patients; almost a fifth were co-infected by more than one herpesvirus. This was more than twice the incidence predicted from clinical evidence before death. Genome detection using nPCR was superior to histological methods for diagnosis of ocular and CNS herpesvirus infection.

Artefactual serum hyperkalaemia and hypercalcaemia in essential thrombocythaemia

AIM

To investigate possible abnormalities of serum potassium and calcium levels in patients with essential thrombocythaemia and significant thrombocytosis.

METHODS

24 cases of essential thrombocythaemia with significant thrombocytosis (platelet count > 700 x 10(9)/litre) had serum potassium and calcium estimations performed at the time of maximum thrombocytosis before treatment, and at the time of low platelet count after treatment with cytoreductive drugs. Selected patients were further investigated with plasma sampling and estimation of ionised calcium and parathyroid hormone.

RESULTS

At the time of maximum thrombocytosis six patients had serum hyperkalaemia (> 5.5 mmol/litre) and five had serum hypercalcaemia (> 2.6 mmol/litre). Following treatment and reduction of the platelet count, hyperkalaemia resolved in all cases and hypercalcaemia in four of the five cases. Mean serum potassium and calcium concentrations were raised (p < 0.0001) at maximum thrombocytosis compared with the values when the platelet count was low. Serum potassium and calcium values were significantly correlated at all stages. Measurements on plasma consistently corrected the hyperkalaemia but not the hypercalcaemia. Serum hypercalcaemia was associated with raised ionised calcium and normal parathyroid hormone concentrations.

CONCLUSIONS

Essential thrombocythaemia with significant thrombocytosis is associated with serum hyperkalaemia and hypercalcaemia. The probable mechanism of hypercalcaemia is the secretion of calcium in vitro from an excessive number of abnormally activated platelets. It is thus likely that the hypercalcaemia is an artefact, as is the hyperkalaemia.

Review of the clinical activity of medical microbiologists in a teaching hospital

BACKGROUND

The clinical interactive role of medical microbiologists has been underestimated and the discipline is perceived as being confined to the laboratory. Previous studies have shown that most microbiology interaction takes place over the telephone.

AIM

To determine the proportion of clinical ward based and laboratory based telephone interactions and specialties using a microbiology service.

METHODS

Clinical microbiology activity that took place during November 1996 was prospectively analysed to determine the distribution of interactions and specialties using the service.

RESULTS

In all, 1177 interactions were recorded, of which nearly one third (29%) took place at the bedside and 23% took place on call. Interactions involving the intensive treatment unit, general ward visits, and communication of positive blood cultures and antibiotic assays were the main areas of activity identified. There were 147 visits to 86 patients on the general wards during the study, with the number of visits to each individual varying from one to eight. The need for repeated visits reflected the severity of the underlying condition of the patients. Ward visits were regarded as essential to obtain missing clinical information, to assess response to treatment, and to make an appropriate entry in a patient's notes.

CONCLUSIONS

Ward visits comprise a significant proportion of clinical microbiology interactions and have potential benefits for patient management, service utilisation, and education.

Early diagnosis of septicaemia in preterm infants from examination of peripheral blood films

Clinically significant staphylococcal septicaemia associated with the presence of bacteria in neutrophils in a routine peripheral blood film is described in four preterm infants. In all cases this allowed the diagnosis of infection prior to the result of microbiological cultures. It is likely that this finding is relatively common in this subgroup of patients resulting from a combination of severe infection associated with indwelling catheters and defective neutrophil bacteriacidal mechanisms. The findings in these cases suggest that careful blood film inspection in selected premature neonates may allow the early identification of sepsis.

Activity of thalidomide in AIDS-related Kaposi's sarcoma and correlation with HHV8 titre

A phase II study of thalidomide was conducted to evaluate its efficacy and toxicity in the treatment of cutaneous AIDS-related Kaposi's sarcoma (AIDS-KS). To evaluate whether clinical response is correlated with titre of human herpesvirus 8 (HHV8) DNA in peripheral blood, levels were determined by serial end-point dilution at enrolment and 4-6 weeks later. Seventeen male HIV-seropositive patients with histopathologically diagnosed KS were treated with thalidomide 100mg orally once nightly for 8 weeks. Response evaluation was performed using AIDS Clinical Trials Group (ACTG) criteria and analysis was by intention to treat. Six of 17 patients achieved a partial response (35%: 95% confidence interval 10-61%). Eight patients withdrew (6 owing to toxicity, one to early progression and one to non-compliance). HHV8 DNA load decreased by at least 3log10 to undetectable levels in 3 of the 5 virologically assessable partial responders. This preliminary study demonstrates that thalidomide has activity in the treatment of AIDS-KS and that clinical response is associated with a reduction of HHV8 DNA titre in peripheral blood.

Detection of Epstein-Barr virus and Kaposi's sarcoma-associated herpesvirus DNA in CSF from persons infected with HIV who had neurological disease

OBJECTIVES

To determine the frequency and clinical relevance of Epstein-Barr virus (EBV) and Kaposi's sarcoma associated herpesvirus (KSHV) DNA detection in the CSF from patients infected with HIV.

METHODS

Cerebrospinal fluid was obtained prospectively from 115 consecutive patients infected with HIV undergoing diagnostic lumbar puncture for investigation of neurological disease. Amplification of DNA was performed using a nested polymerase chain reaction (PCR) for detection of EBV internal repeat and KSHV minor capsid sequences.

RESULTS

EBV DNA was detected in the CSF supernatant of 18 patients. This included all patients with primary CNS lymphoma (seven patients) or a combination of systemic and CNS lymphoma (two patients). By contrast EBV DNA was not detected in the CSF supernatant of any patient with systemic, but not CNS, lymphoma (10 patients). EBV DNA was also detected in the supernatant of nine further patients without a diagnosis of lymphoma at the time of lumbar puncture, two of whom subsequently developed CNS lymphoma. No EBV DNA was detected in CSF supernatant from the remaining 87 samples (two of these patients subsequently developed lymphoma). KSHV DNA was detected in the CSF of two patients, one had systemic (but not CNS) lymphoma and the other did not have lymphoma.

CONCLUSION

A diagnosis of CNS lymphoma is strongly associated with the presence of EBV DNA in CSF. In the absence of clinical and radiological features of CNS lymphoma, the presence of detectable CSF EBV DNA may predict subsequent tumour development. KSHV DNA is rarely detected in CSF in this patient group and shows no correlation with lymphoma or other neurological disease.

Association of Kaposi's sarcoma associated herpesvirus (KSHV) DNA in bronchoalveolar lavage fluid of HIV infected individuals with bronchoscopically diagnosed tracheobronchial Kaposi's sarcoma

OBJECTIVES

To determine the frequency of detection of Kaposi's sarcoma associated herpesvirus (KSHV), also known as human herpesvirus (HHV) type 8, DNA in bronchoalveolar lavage (BAL) fluid from HIV infected individuals with and without KS and to compare this with the detection rate in peripheral blood. Also to identify whether KSHV was associated with specific cell types in lavage fluid.

METHODS

Nested PCR was used to detect KSHV DNA in BAL fluid from 41 consecutive individuals with Kaposi's sarcoma (KS) and in 41 controls with similar CD4 lymphocyte counts. Semiquantification of viral DNA was by end point titration. A positive cell sorting selection procedure was used to isolate specific BAL fluid cell types.

RESULTS

KSHV DNA was detected in BAL fluid from 24 of 29 (83%) individuals with a bronchoscopic diagnosis of tracheobronchial KS. None was detected in 12 individuals with only cutaneous KS, or in 41 matched controls without KS. In five, KSHV DNA was detected in the cell depleted and cellular fractions of BAL fluid and in 1/5 in the CD14 (macrophage) fractions. None was detected in the CD19 (B lymphocyte) or CD4/CD8 (T lymphocyte) fractions.

CONCLUSIONS

There was a clear association between the diagnosis of tracheobronchial KS and detection of KSHV DNA in BAL fluid. The cell type supporting KSHV in the respiratory tract is not CD 19 positive and has yet to be conclusively identified.

Kaposi's sarcoma-associated herpes virus--a new concern for human reproduction?

The detection of the recently discovered Kaposi's sarcoma-associated herpes virus (KSHV) in human immunodeficiency virus-uninfected donor semen and in blood from a normal blood donor has led us to review this new area of health concern, with emphasis on a number of studies conducted into the presence of the virus in semen and the possibility of transmission during assisted conception procedures.

Detection of human herpesvirus 8 DNA in semen from HIV-infected individuals but not healthy semen donors

OBJECTIVE

To ascertain the prevalence of Kaposi's sarcoma-associated herpesvirus (KSHV), also known as human herpesvirus (HHV) type 8, and cytomegalovirus (CMV) DNA in semen was investigated.

METHODS

Amplification by nested polymerase chain reaction was used to detect viral DNA sequences in samples from 24 HIV-infected gay men, 15 of them with Kaposi's sarcoma (KS), and 115 healthy donors.

RESULTS

Six of the 24 HIV-infected patients had detectable HHV-8 DNA in their semen: three of the 15 patients with KS and three of the nine patients without KS. CMV DNA was detected in 20 semen samples from HIV-infected patients. None of the semen samples from healthy donors had detectable HHV-8 DNA and rates of CMV DNA detection were low (3%).

CONCLUSIONS

The study demonstrates the presence of HHV-8 in semen from HIV-infected individuals with, or at risk, of developing KS and the potential for sexual transmission of the virus. We found no evidence of HHV-8 in the semen of HIV-uninfected donors.

Prevalence of Kaposi's sarcoma associated herpesvirus infection measured by antibodies to recombinant capsid protein and latent immunofluorescence antigen

BACKGROUND

Kaposi's sarcoma-associated herpesvirus (KSHV), also known as human herpesvirus 8, may be the infectious cause of KS. Its prevalence in the general population, on the basis of detection of the virus genome, is controversial. To investigate the seroprevalence, we measured antibodies to a recombinant capsid-related (lytic cycle) KSHV antigen and a latent antigen complex.

METHODS

We selected potentially immunoreactive capsid-related proteins of KSHV by expressing them as recombinant proteins and testing them in western blot assays. We used a truncated recombinant protein encoded by KSHV open reading frame 65 (orf 65) to develop a diagnostic enzyme-linked immunosorbent assay (ELISA) and tested sera from HIV-infected individuals with KS, HIV-uninfected patients with "classic" KS, other HIV risk groups, and blood donors. We also compared the antibody response to this capsid-related protein to the response to latent antigen(s) in an immunofluorescence assay.

FINDINGS

77/92 (84%) sera from KS patients reacted with the KSHV orf 65 protein and 84/103 (81.5%) reacted with KSHV latent antigen(s). The dominant immunogenic region of orf 65 is within the carboxyterminal 80 aminoacids, a region with little sequence similarity to the related Epstein-Barr virus, suggesting that orf 65 is a KSHV specific antigen. Only three sera from patients with haemophilia (1/84) or from intravenous drug users (2/63) had KSHV specific antibodies in the orf 65 assay whereas none of these sera reacted with latent antigen. Antibodies to KSHV were also infrequently found in UK and US blood donors by either assay (UK, 3/174 with orf 65 and 4/150 with latent antigen; US, 6/117 with orf 65 and 0/117 with latent antigen). They were more common among HIV-infected gay men without KS (5/16 by orf 65 ELISA, 10/33 by IFA), HIV-uninfected STD clinic attenders (14/166 by IFA), and Ugandan HIV-uninfected controls (6/17 by orf 65 ELISA, 9/17 by IFA). Antibody reactivity to the orf 65 protein (ELISA) and to latent antigen(s) (IFA) was concordant in 89% of 462 sera tested but reactive blood donor sera were discordant in both assays. Four AIDS-KS sera were unreactive in both assays.

INTERPRETATION

The distribution of antibodies to both a capsid-related recombinant protein and latent antigen(s) of KSHV strongly supports the view that infection with this virus is largely confined to individuals with, or at increased risk for, KS. However, infection with KSHV does occur, rarely, in the general UK and US population and is more common in Uganda. Antibodies to latent antigen(s) or to orf 65 encoded capsid protein will not detect all cases of KSHV infection, and a combination of several antigens will probably be required for accurate screening and confirmatory assays.

The Alder-Reilly anomaly in association with the myelodysplastic syndrome

We describe the Alder-Reilly morphological abnormality in an elderly man with a myelodysplastic syndrome (MDS). The literature pertaining to abnormal neutrophil hypergranulation is reviewed and the possible role of myelodysplasia in its causation is discussed.

Detection of Kaposi sarcoma associated herpesvirus in peripheral blood of HIV-infected individuals and progression to Kaposi's sarcoma

Kaposi sarcoma-associated herpesvirus (KSHV) is consistently found in biopsy samples from patients with AIDS-related and "classical" Kaposi's sarcoma (KS). Although highly suggestive of a causal role of KSHV in the pathogenesis of KS, this observation does not exclude the possibility that KSHV, like other herpesviruses, is widely distributed and is a mere "passenger" in these lesions. Here we report that KSHV was detectable in peripheral blood mononuclear cells of 24/46 (52%) of KS patients, but in none of 134 blood donors or 26 HIV-uninfected hospital controls. KSHV detection increased with immunosuppression, as shown by a correlation with a reduced number of CD4-positive T-cells. Moreover, KSHV detection in peripheral blood cells of HIV-infected individuals without KS predicted the subsequent appearance of KS lesions. 143 patients who did not have KS at the time of their first (or only) blood sample were followed up for a median of 30 months. Of the 11 who had been KSHV positive 6 developed KS compared with only 12 out of 132 who were KSHV negative. These findings are compatible with a causative role of KSHV in KS. KSHV was rarely detected in sputum and throat swabs of HIV-infected patients, providing a potential explanation for the apparently limited spread of this virus.