A99 EFFICACY OF THE IN-HOSPITAL OBSERVATORY PERIOD FOR IBD PATIENTS WITH FLARE TREATED WITH ORAL CORTICOSTEROIDS

Background

Inflammatory Bowel Disease (IBD) is a chronic, debilitating collection of diseases with significant impairment to patient quality of life and hospital burden. Patients with acute flare of their disease are managed with IV corticosteroids and ultimately transitioned to an oral equivalent. Despite no formal guideline recommendation, some patients remain in hospital on oral corticosteroids, primarily for observation. Given that each day spent in hospital carries significant costs, examining this observatory period is warranted. The utility of the observatory period for patients recently switched to oral corticosteroids has not yet been studied and may be unnecessarily increasing hospital stays and costs to the Canadian medical system.

Purpose

- Analyse the efficacy of the in-hospital period for patients on oral corticosteroids after an acute IBD flare in preventing recurrence in the 14 and 28 days post discharge.

- Assess the relationship between length of the in-hospital “observatory” period with future hospital burden.

Method

- This retrospective cohort study identified patients with known IBD who were admitted to Royal Columbian Hospital under the Gastroenterology service primarily for acute flare of their disease from June 1, 2020 to June 30^th, 2022. Patients were identified through the clinic EMR (Plexia) and hospital information was accessed via the Fraser Health Health Records Department. This study acheived ethics approval by the Fraser Health Research Ethics Board (Event: 2022376).

- Inclusion criteria are as follows:

- Age > 18 years old

- Prior diagnosis of IBD as per CAG guidelines

- Acute IBD flare is primary reason for hospitalization

- Hospital management includes IV corticosteroids and discharge medications include a tapering course of oral corticosteroid.

- Exclusion criteria are as follows:

- Patients found to be non-compliant on outpatient medication regimen (i.e tapering dose of PO prednisone).

- Patients with a complicated course in management (concurrent illness that impacted hospital stay).

Result(s)

-20 patients were identified, with 60 total hospital admissions.

-35 visits included an observatory period, with 6 less than 24hr (1 hospital re-presentation), and 29 greater than 24hr (3 hospital re-presentations).

-25 visits did not have an observatory period.

-The relative risk of patients without an observatory period returning to hospital within 14 and 28 days compared to those with an observatory period was 4.2 and 1.75, respectively.

Conclusion(s)

These preliminary results suggest an increased relative risk for those without an in-hospital observatory period for short term re-hospitalization. However, we hypothesize this will significantly change once we have broadened our date range and increased our total number of hospitalizations, which is planned prior to the poster presentation date.

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None

Disclosure of Interest

None Declared

A179 AUTOLOGOUS BONE MARROW TRANSPLANT FOR REFRACTORY CROHN’S DISEASE: A CASE SERIES

Background

Crohn’s disease (CD), a form of inflammatory bowel disease (IBD) is a chronic, immune mediated condition characterized by gastrointestinal inflammation. Approximately 25% of CD patients have pharmacologically refractory disease, in which stem cell therapy has been shown to play a role.

Aims

A case series was performed to analyze the efficacy of autologous bone marrow transplantation (ABMT) for refractory CD in British Columbia(B.C).

Methods

A chart review was conducted on patients who had undergone ABMT for treatment refractory CD between 2001 to 2021 in B.C. Demographic, clinical, laboratory and endoscopic data was collected.

Results

Case details are summarized in Table 1. 3 patients(2 female and one male) were included. All patients failed conventional therapies prior to ABMT. 2 patients underwent surgical intervention (colectomy with ileostomy) prior to ABMT. Average time from diagnosis to ABMT was 8.83 + 6.6 years. All 3 patients received standard myeloablative therapy. There were no intestinal complications post ABMT. 6 months post-ABMT transplant, all 3 patients showed significant improvement, with CDAI scores <150. Endoscopic assessment post-ABMT revealed endoscopic remission in 2 of the 3 patients. 2 of the 3 patients were in clinical remission at 12 months follow up. 1 patient relapsed and required further immunosuppressive therapy. This patient was trialed on thalidomide at 15 months post-ABMT and ultimately passed away 18 months post-ABMT from an unrelated cause. 10 years post-transplant, the remaining 2 patients remain in clinical and endoscopic remission with CDAI scores <150.

Conclusions

Despite medical and surgical therapeutic advances, a subset of CD patients develop refractive disease associated with significant morbidity and mortality. In this population, there is increasing evidence in support of stem cell therapy as a treatment modality, with acute mortality less than 5% for patients with malignancy driven primarily by infectious complications and treatment-related toxicity. Clinical trials are currently underway to evaluate ABMT in CD. This case series presents the only Canadian data to date on the use of ABMT for refractory CDs and their subsequent follow up.

Funding Agencies

None

Humoral immune responses to COVID-19 vaccination in people living with HIV receiving suppressive antiretroviral therapy

Humoral responses to COVID-19 vaccines in people living with HIV (PLWH) remain incompletely understood. We measured circulating antibodies against the receptor-binding domain (RBD) of the SARS-CoV-2 spike protein, ACE2 displacement and live viral neutralization activities one month following the first and second COVID-19 vaccine doses in 100 adult PLWH and 152 controls. All PLWH were receiving suppressive antiretroviral therapy, with median CD4+ T-cell counts of 710 (IQR 525-935) cells/mm 3 . Nadir CD4+ T-cell counts ranged as low as <10 (median 280; IQR 120-490) cells/mm 3 . After adjustment for sociodemographic, health and vaccine-related variables, HIV infection was significantly associated with 0.2 log 10 lower anti-RBD antibody concentrations (p=0.03) and ∼11% lower ACE2 displacement activity (p=0.02), but not lower viral neutralization (p=0.1) after one vaccine dose. Following two doses however, HIV was no longer significantly associated with the magnitude of any response measured. Rather, older age, a higher burden of chronic health conditions, and having received two ChAdOx1 doses (versus a heterologous or dual mRNA vaccine regimen) were independently associated with lower responses. After two vaccine doses, no significant correlation was observed between the most recent or nadir CD4+ T-cell counts and vaccine responses in PLWH. These results suggest that PLWH with well-controlled viral loads on antiretroviral therapy and CD4+ T-cell counts in a healthy range will generally not require a third COVID-19 vaccine dose as part of their initial immunization series, though other factors such as older age, co-morbidities, vaccine regimen type, and durability of vaccine responses will influence when this group may benefit from additional doses. Further studies of PLWH who are not receiving antiretroviral treatment and/or who have low CD4+ T-cell counts are needed.

Untimed Efavirenz Drug Levels After Switching From Brand to Generic Formulations: A Short Communication

BACKGROUND

In British Columbia, antiretrovirals are distributed at no cost to patients via a publicly funded program, using generic formulations if available. A generic efavirenz-emtricitabine-tenofovir DF (EFV-FTC-TDF) combination pill became available in April 2018. The authors compared EFV untimed drug levels in subjects switching from brand to generic EFV-FTC-TDF.

METHODS

Archived plasma HIV viral load samples were identified for consenting participants who switched from brand to generic EFV-FTC-TDF; 3 preswitch and 2-3 postswitch samples, collected ≥1 month apart were assessed for each subject. "Untimed" EFV concentrations with unknown dosing and collection time were assessed using a validated liquid chromatography-tandem mass spectrometry method. Participants' mean, minimum, and maximum EFV levels were compared using the Wilcoxon signed rank test. Participants with EFV levels in the range associated with lower risks of virologic failure and central nervous system toxicity (1000-4000 ng/mL), preswitch and postswitch, were enumerated.

RESULTS

EFV levels were assessed in 297 preswitch and 249 postswitch samples from 99 participants, having exposure to brand and generic EFV for a median of 103 (Q1-Q3: 87-116) and 10.3 (Q1-Q3: 8.9-11.7) months, respectively. The final brand sample was collected at a median of 98 days preswitch; the first generic sample was collected at a median of 133 days postswitch. No significant differences were observed in participant mean EFV levels before (median 1968 ng/mL; Q1-Q3: 1534-2878 ng/mL) and after (median 1987 ng/mL; Q1-Q3: 1521-2834 ng/mL) switch (P = 0.85). Eighty participants had mean EFV levels within the 1000-4000 ng/mL range on the brand drug, of which 74 remained within this range postswitch.

CONCLUSIONS

There were no statistically significant differences between untimed EFV levels in patients switching from the brand to generic EFV combination pill. Given the long elimination half-life of EFV, untimed drug levels may be a convenient way to estimate product bioequivalence.

A60 SIGNIFICANCE OF IBD DIAGNOSIS IN THE BC COLON SCREENING PROGRAM

Background

There has been evidence of incidental inflammatory bowel disease (IBD) diagnosis in otherwise asymptomatic patients during colonoscopy to follow-up a positive fecal immunochemical test (FIT). Little is known about the significance of subclinical disease and its progression in this population.

Aims

To determine the incidence and outcome of subclinical IBD in a colon screening program. We hypothesize that the proportion of patients receiving biologic or surgical intervention would be low.

Methods

IBD cases were identified using the BC Colon Screening Program (BCCSP) database; pilot program at 3 sites from 01/2009–11/2013, and province-wide from 11/2013- 12/2017. Inclusion criteria: diagnosis of IBD at BCCSP colonoscopy performed for positive FIT. Exclusion criteria: prior IBD diagnosis, microscopic colitis. Data obtained through chart review included: demographics, endoscopy and histology reports, and medical/surgical treatment.

Results

Of 93,994 colonoscopies, 608 were diagnosed with IBD (0.65%) (Figure 1). Chart review of 245 cases at 10 institutions was performed. 65 patients were excluded. Of the 180 cases included, the average age at diagnosis was 59.6 years and 58.9% were male. 70.6% of patients were Caucasian, 12.2% were East Asian, and 7.8% South-east Asian. 49.4% were diagnosed with Crohn’s disease (CD), 33.9% with Ulcerative Colitis (UC), and 16.7% with indeterminate colitis, with a median follow-up of 25.5 months (0–85.9 months). 62.8% of patients received treatment, with 17.8% requiring biologic therapy, and 1.7% requiring surgical intervention.

Conclusions

This is the largest study assessing subclinical IBD in a colon screening program, with IBD incidence comparable to other publications in this population. However, the high proportion of patients diagnosed with CD is a novel finding. Also, subclinical IBD is not as benign as previously reported as nearly 20% of patients required biologics and/or surgical intervention.

Funding Agencies

None

Algorithms for Argumentation Semantics: Labeling Attacks as a Generalization of Labeling Arguments

A Dung argumentation framework (AF) is a pair (A,R): A is a set of abstract arguments and R ⊆ A×A is a binary relation, so-called the attack relation, for capturing the conflicting arguments. Labeling based algorithms for enumerating extensions (i.e. sets of acceptable arguments) have been set out such that arguments (i.e. elements of A) are the only subject for labeling. In this paper we present implemented algorithms for listing extensions by labeling attacks (i.e. elements of R) along with arguments. Specifically, these algorithms are concerned with enumerating all extensions of an AF under a number of argumentation semantics: preferred, stable, complete, semi stable, stage, ideal and grounded. Our algorithms have impact, in particular, on enumerating extensions of AF-extended models that allow attacks on attacks. To demonstrate this impact, we instantiate our algorithms for an example of such models: namely argumentation frameworks with recursive attacks (AFRA), thereby we end up with unified algorithms that enumerate extensions of any AF/AFRA.

Closed system isolation and scalable expansion of human placental mesenchymal stem cells

Mesenchymal stem cells (MSC) are emerging as a leading cellular therapy for a number of diseases. However, for such treatments to become available as a routine therapeutic option, efficient and cost-effective means for industrial manufacture of MSC are required. At present, clinical grade MSC are manufactured through a process of manual cell culture in specialized cGMP facilities. This process is open, extremely labor intensive, costly, and impractical for anything more than a small number of patients. While it has been shown that MSC can be cultivated in stirred bioreactor systems using microcarriers, providing a route to process scale-up, the degree of numerical expansion achieved has generally been limited. Furthermore, little attention has been given to the issue of primary cell isolation from complex tissues such as placenta. In this article we describe the initial development of a closed process for bulk isolation of MSC from human placenta, and subsequent cultivation on microcarriers in scalable single-use bioreactor systems. Based on our initial data, we estimate that a single placenta may be sufficient to produce over 7,000 doses of therapeutic MSC using a large-scale process.

Cold knife versus laser cone biopsy for adenocarcinomain situof the cervix-a comparison of management and outcome

Eighty-two patients with adenocarcinoma in situ of the cervix managed at Royal Prince Alfred Hospital were reviewed and data were collected on those treated by cold knife cone biopsy (n= 38) and laser cone biopsy (n= 44). No differences were found in patient age, cytologic or referral history, or outcomes. Having laser excision did not compromise margin status or subsequent management. Invasive disease was found in 24 patients, 16 of whom were managed conservatively with good outcome. Twelve of these were in the laser cone group. In those patients from both groups managed conservatively, there was only one recurrence, squamous preinvasive disease after 8 years. Laser cone biopsy is as effective as cold knife cone biopsy with no compromise of outcome for these patients.

Immunosuppression by placental indoleamine 2,3-dioxygenase: a role for mesenchymal stem cells

BACKGROUND/OBJECTIVES

Mesenchymal stem cells (MSC) can be isolated from human placenta and have the potential to contribute to the immunosuppressive properties of placental tissue. The objectives of this study were to investigate the phenotype and differentiation characteristics of MSC derived from human placenta and evaluate the role of the tryptophan degrading enzyme, indoleamine 2,3 dioxygenase (IDO), in mediating their immunosuppressive affect.

METHODS

MSC obtained from placental tissue (pMSC) were characterised using flow cytometry and tested for multipotency by determining differentiation into all mesenchymal lineages. The immunosuppressive properties of pMSC were tested in allogeneic mixed lymphocyte reactions and IDO expression and activity were measured by semi-quantitative real-time PCR and HPLC respectively.

RESULTS

Multipotent stem cells were isolated from placenta and displayed chondrogenic, osteogenic and limited adipogenic differentiation. Cell surface antigen expression of pMSC was similar to bone marrow MSC (bMSC) with lack of the haematopoietic and common leukocyte markers (CD34, CD45), and expression of adhesion (CD29, CD166, CD44) and stem cell (CD 90, CD105, CD73) markers. Placental MSC were suppressive of allogeneic T-cell proliferation, an effect which was intensified following IDO induction by IFN-gamma. Replenishment of tryptophan or treatment with the IDO-blocker, 1-methyl-tryptophan (1-MT), attenuated the immunosuppressive action of pMSC.

CONCLUSIONS

These results suggest that placental tissue contains MSC, which are phenotypically and functionally similar to bMSC, and that IDO is a key mediator of their immunosuppressive effect. Further investigation is needed to determine if pMSC function effects pregnancy outcome.

Standards and performance--attainment and maintenance of professional capabilities

The nature of The Royal Australian College of General Practitioners (RACGP) examination came under scrutiny in a recent debate among RACGP members, some of who suggested exploring an alternative pathway for assessment linked to continuing medical education. This article outlines key issues underpinning the examination that is part of the requirements for attaining Fellowship of the RACGP (FRACGP). It provides an overview of the theory and practice of assessment for general practice. The RACGP examination has an international reputation for quality, validity and reliability, a reason why the RACGP has been asked to assist many others in establishing and/or reviewing their own examination processes.

CD8+ cell depletion of donor lymphocyte infusions using cd8 monoclonal antibody-coated high-density microparticles (CD8-HDM) after allogeneic hematopoietic stem cell transplantation: a pilot study

A CD8 murine monoclonal antibody-coated high-density microparticle (HDM) has been developed, which allows for the rapid depletion of CD8+ T cells from apheresis products by gravity sedimentation. We conducted a study to determine the efficacy and safety of CD8 depletion of donor lymphocyte infusions (DLI) to treat relapse after stem cell transplantation using the Eligix CD8-HDM Cell Separation System. Patients were targeted to receive 3 x 10(7) CD4+ T cells/kg. Nine patients were enrolled, three with CML, three myeloma, two CLL, and one NHL. A median of 1 x 10(10) mononuclear cells were obtained by apheresis and processed. The median depletion of CD8+ cells was 99.3% (97.8->99.5%). CD8 depletion was highly specific, with a median recovery of CD4+ cells of 75%. A median of 2.9 x 10(7) CD4+ cells/kg was infused. No infusional toxicity was noted. All CML patients achieved a complete molecular remission. A CLL patient demonstrated a complete response. One patient developed GVHD (grade II acute GVHD and subsequently chronic GVHD). The CD8-HDM Cell Separation System appears to be highly selective and effective in depleting CD8+ T cells from DLI apheresis products, and CD8-depleted DLI is capable of mediating a graft-versus-leukemia effect while minimizing GVHD.

Transplantation of highly purified CD34+Thy-1+ hematopoietic stem cells in patients with recurrent indolent non-Hodgkin's lymphoma

PURPOSE

To evaluate the results of high-dose chemotherapy and transplantation of highly purified "mobilized" peripheral blood CD34+Thy-1+ hematopoietic stem cells (HSCs) in patients with recurrent indolent non-Hodgkin's lymphoma (NHL) or mantle cell lymphoma (MCL).

PATIENTS AND METHODS

Twenty-six patients with recurrent indolent NHL or MCL were mobilized witheither granulocyte colony-stimulating factor (G-CSF) alone or cyclophosphamide plus G-CSF. Apheresis was performed, and the product was purified using the Isolex immunomagnetic positive CD34+ cell selection device initially and subsequent high-speed flow-cytometric cell sorting for the final purification of CD34+Thy-1+ HSCs. The patients received high-dose chemotherapy with BEAC (carmustine, etoposide, cytarabine, and cyclophosphamide) followed by transplantation with the purified HSCs in 2 dose cohorts (cohort 1: > or =5 x 10(5) viable and pure HSC/kg; cohort 2: > or =3 x 10(5) HSC/kg).

RESULTS

We attempted to mobilize 26 patients with G-CSF alone. Six patients did not collect adequate cells with G-CSF alone; subsequent mobilization with cyclophosphamide plus G-CSF was attempted, but adequate CD34+Thy-1+ HSCs could not be collected on these 6 patients. Twenty patients underwent transplantation with the BEAC transplantation regimen followed by purified HSCs. Patients in cohort 1 engrafted at a median of day 12 to an absolute neutrophil count (ANC) >500/microL, a median of day 19 for platelet transfusion independence, and a median of day 20 for red blood cell transfusion independence. Patients in cohort 2 engrafted at a median of day 12 to an ANC >500/microL, a median of day 12 for platelet transfusion independence, and a median of day 12 for red blood cell transfusion independence. Fourteen of the 20 patients had significant infections reported at some point posttransplantation, including influenza, respiratory syncytial virus, pneumonitis, and Pneumocystis carinii pneumonia. With a median follow-up of 38 months, 8 of the 20 patients have had progressive lymphoma and 5 patients have died. The 3-year event-free survival is 55%, and overall survival is 78%.

CONCLUSIONS

CD34+Thy-1+ HSCs can be collected successfully from most lymphoma patients mobilized with G-CSF alone. The engraftment and disease outcomes in the patients in this small pilot study using these cells do not appear to be different from the outcomes of similar patients cited in the literature. However, the short- and long-term risks of infection were a concern in this patient population.

High grade abnormalities following an 'inconclusive' smear

OBJECTIVE

The National Health and Medical Research Council (NHMRC) recommends a report of 'inconclusive possible high grade epithelial abnormality', but many laboratories only report 'inconclusive' with reference to any possible high grade disease elsewhere in the report. This study was performed to determine possible reasons for cytological difficulties resulting in this category of report and to determine the rate of significant disease within this category.

DESIGN

Retrospective record review. Clinical details were extracted without patient-identifying data.

SETTING

Gynaecological Oncology Department, King George V/Royal Prince Alfred Hospital.

POPULATION

Two hundred patients referred with the cytological abnormality.

MATERIALS AND METHODS

An adequate colposcopic diagram documenting size, distribution and grade of lesion was required. All patients had colposcopy with management according to colposcopic and histological results as appropriate to their disease.

OUTCOME MEASURES

Colposcopic features, topography and size of any lesion, histological results, treatments performed and subsequent review of untreated patients.

RESULTS

Colposcopy found high-grade lesions in 43% and carcinoma in 1%. Histopathology found 49% and 4% respectively. Treatment was performed in 124 patients. Inflammation was found in 27%, a small lesion in 43% and endocervical disease in 21%.

CONCLUSIONS

The high rate of endocervical disease, inflammation and small lesions may explain the cytological difficulties leading to an 'inconclusive' result. The authors believe that the term 'inconclusive' alone does not adequately convey the high level of risk faced by these patients.

Characterization of humoral and cellular immune responses elicited by meningococcal carriage

In order to study the immune response elicited by asymptomatic carriage of Neisseria meningitidis, samples of serum, peripheral blood mononuclear cells (PBMCs), and saliva were collected from a cohort of more than 200 undergraduate students in Nottingham, United Kingdom, who were subject to high rates of acquisition and carriage of meningococci. Serum immunoglobulin G levels were elevated following increases in the rate of carriage, and these responses were specific for the colonizing strains. In order to investigate T-cell responses, PBMCs from 15 individuals were stimulated with a whole-cell lysate of the H44/76 meningococcal strain (B:15:P1.7,16), stained to detect cell surface markers and intracellular cytokines, and examined by flow cytometry. The cells were analyzed for expression of CD69 (to indicate activation), gamma interferon (IFN-gamma) (a representative T-helper 1 subset [Th1]-associated cytokine), and interleukin-5 (IL-5) (a Th2-associated cytokine). Following a brief meningococcal stimulation, the numbers of CD69(+) IFN-gamma(+) CD56/16(+) NK cells were much higher than cytokine-positive CD4(+) events. Both IFN-gamma(+) and IL-5(+) events were detected among the CD69(+) CD4(+) population, leading to the conclusion that an unbiased T-helper subset response was elicited by meningococcal carriage.

A two-phase pathogenesis of graft-versus-host disease in mice

Activation of donor T cells is required for the development of graft-versus-host disease (GVHD), a major complication of bone marrow transplantation. We investigated a murine model of GVHD across major and minor histocompatibility barriers. BALB/c recipients were lethally irradiated and transplanted with 10(7) bone marrow and 5 x 10(6) spleen cells from C57BL/6 donors. There were two separate phases of clinical disease. The first phase was most severe on day 7 after transplant. Weight and condition improved until day 12 and then a second phase of clinical GVHD commenced, which persisted until euthanasia. IL-2 mRNA expression, as a measure of T cell activation, was determined by quantitative PCR. The two phases of clinical GVHD were preceded by two separate peaks of IL-2 mRNA in the spleen. Host MHC class II(+) cells became undetectable by flow cytometry 7 days after transplantation, whereas donor MHC class II(+) cells increased during the first 9 days after transplantation. Removal of donor MHC class II(+) cells from the graft had no effect on the first phase. Possible roles for host and donor antigen-presenting cells (APC) in the two phases of the disease are discussed.

A public health response to emerging technology: expansion of the Massachusetts newborn screening program

The development of a new technology, called tandem mass spectrometry (tandem MS), has challenged governments worldwide to consider expanding universal newborn screening for rare metabolic disorders. In 1997 the Massachusetts Department of Public Health developed a public process to meet this challenge. After addressing significant medical, legal, ethical, and logistical issues raised by tandem MS, Massachusetts incorporated one new disorder into the mandatory newborn screen and developed an optional pilot program for 20 additional disorders. The Massachusetts experience has wide relevance for other nations and states. As screening protocols are contemplated for entire populations-for newborns and others- it will remain essential that the public participate in an open process of reviewing the justification for and logistics of screening.

Transplantation of highly purified CD34+Thy-1+ hematopoietic stem cells in patients with metastatic breast cancer

We report here the transplantation of extensively purified "mobilized" peripheral blood CD34Thy-1 hematopoietic stem cells from 22 patients with recurrent or metastatic breast cancer. Patients were mobilized with either high-dose granulocyte colony-stimulating factor (G-CSF) alone or cyclophosphamide plus G-CSE Median purity of the stem cell product at cryopreservation was 95.3% (range, 91.1%-98.3%), and viability was 98.6% (range, 96.5%-100%). After high-dose chemotherapy with carmustine, cisplatin, and cyclophosphamide, CD34+Thy-1 cells at a median dose of 11.3 x 10(5) per kilogram (range, 4.7-163 x 10(5) per kilogram) were infused. No infusion-related toxicity was observed. Neutrophil recovery was prompt, with median absolute neutrophil count >500/microL by day 10 (range, 8-15 days) and >1000/microL by day 11 (range, 8-17 days). Median platelet recovery (>20,000/microL) was observed by day 14 (range, 9-42 days) and >50,000/microL by day 17 (range, 11-49 days). Tumor cell depletion below the limits of detection of a sensitive immunofluorescence-based assay was accomplished in all patients who had detectable tumor cells in apheresis products before processing. Although CD4+ T-cell reconstitution was slow, no unusual infections were observed. Neither early nor late graft failure was observed, and no patient required infusion of unmanipulated backup cells. At a median follow-up of approximately 1.4 years and a maximum follow-up of 2.5 years, 16 of the 22 patients remain alive, with 9 free of disease progression, and have stable blood counts. In summary, highly purified CD34+Thy-1+ cells used as the sole source of the hematopoietic graft result in rapid and sustained hematopoietic engraftment.

Transplantation with selected autologous peripheral blood CD34+Thy1+ hematopoietic stem cells (HSCs) in multiple myeloma: impact of HSC dose on engraftment, safety, and immune reconstitution

OBJECTIVE

The aims of our study performed in myeloma were to evaluate the performance and the safety of Systemix's high-speed clinical cell sorter, to assess the safety and efficacy of deescalating cell dose cohorts of CD34+Thyl+ hematopoietic stem cells (HSCs) as autologous grafts by determining engraftment, and to assess the residual tumor cell contamination using polymerase chain reaction (PCR) amplification assays of patient-specific complementarity determining region III (CDR III) analysis for residual myeloma cells.

MATERIALS AND METHODS

The clinical trial was performed in 31 multiple myeloma patients, using purified human CD34+Thyl+ HSCs mobilized from peripheral blood with cyclosphosphamide and granulocyte-macrophage colony-stimulating factor to support a single transplant after high-dose melphalan 140 mg/m2 alone (cohort 1) and with total body irradiation (TBI) (cohorts 2-5) after an HSC transplant cell dose de-escalation/escalation design.

RESULTS

Twenty-three patients were transplanted. Engraftment data in the melphalan + TBI cohorts confirmed that HSC doses above the threshold dose of 0.8 x 10(6) CD34+Thy1+ HSCs/ kg provided prompt engraftment (absolute neutrophil count >0.5 x 10(9)/L day 10; platelet count >50 x 10(9)/L day 13). A higher rate of infections was observed in the early and late follow-up phases than usually reported after CD34+ selected or unselected autologous transplantation, which did not correlate with the CD34+Thy1+ HSC dose infused. Successful PCR for CDR III could only be performed in five patients on initial apheresis product and final CD34+Thy1+ HSC product and showed a median tumor log reduction >3.12.

CONCLUSIONS

CD34+Thy1+ HSCs are markedly depleted or free of detectable tumor cells in multiple myeloma and are capable of producing fast and durable hematopoietic reconstitution at cell doses >0.8 x 10(6) CD34+Thy1+ HSCs/kg. The delayed immune reconstitution observed is not different from that described in unselected autologous bone marrow and peripheral blood mononucleated cells transplants in multiple myeloma and may be corrected by addition of T cells either to the graft or to the patient in the posttransplant phase.

Vanilloid receptor-1 is essential for inflammatory thermal hyperalgesia

The vanilloid receptor-1 (VR1) is a ligand-gated, non-selective cation channel expressed predominantly by sensory neurons. VR1 responds to noxious stimuli including capsaicin, the pungent component of chilli peppers, heat and extracellular acidification, and it is able to integrate simultaneous exposure to these stimuli. These findings and research linking capsaicin with nociceptive behaviours (that is, responses to painful stimuli in animals have led to VR1 being considered as important for pain sensation. Here we have disrupted the mouse VR1 gene using standard gene targeting techniques. Small diameter dorsal root ganglion neurons isolated from VR1-null mice lacked many of the capsaicin-, acid- and heat-gated responses that have been previously well characterized in small diameter dorsal root ganglion neurons from various species. Furthermore, although the VR1-null mice appeared normal in a wide range of behavioural tests, including responses to acute noxious thermal stimuli, their ability to develop carrageenan-induced thermal hyperalgesia was completely absent. We conclude that VR1 is required for inflammatory sensitization to noxious thermal stimuli but also that alternative mechanisms are sufficient for normal sensation of noxious heat.

Surgery and post-operative radiotherapy for early stage cervical cancer

The use of post-operative radiotherapy in the treatment of cervical cancer is controversial. The aim of this study was to document the results and toxicity of adjuvant irradiation in patients with Stage 1B and 2A cervical cancer. We performed a retrospective review of all patients treated with post-operative radiotherapy at Royal Prince Alfred Hospital between 1986 and 1993. Patient, tumour and treatment factors and late toxicity were recorded. Relapse-free and overall survival were calculated. Eighty-one patients form the study population. The median follow-up was 6.1 years. Fifty-eight patients (72%) had stage 1B cervical cancer and 23 (28%) stage 2A. The 5 year relapse-free and overall survival were 78% and 80% respectively. Six patients (7%) had late toxicity requiring inpatient medical treatment and 6 patients (7%) required surgery. The survival was comparable to other series reported in the literature. There was an incidence of 14% late toxicity requiring medical or surgical intervention which is greater than with hysterectomy or pelvic irradiation alone. Clinical prognostic factors should be used to select patients for either surgery or radiotherapy alone to minimise the increased toxicities associated with a combination of surgery and radiotherapy.

Informing older patients of a terminal illness

Nurses must guard against an ageist approach to care--older people do not necessarily need 'protecting' from bad news. Excellent palliative care is required by all patients with a terminal illness--regardless of their condition. All patients have a right to know their prognosis and to prepare for death.

Adjuvant high-dose rate brachytherapy with or without external beam radiotherapy post-hysterectomy for endometrial cancer

The purpose of this study was to evaluate patient selection, local control, survival and late toxicity of posthysterectomy adjuvant radiotherapy and compare adjuvant external beam therapy and high-dose rate (HDR) brachytherapy versus HDR brachytherapy alone. A retrospective analysis was performed on a series of 225 patients with endometrial cancer treated with external beam radiotherapy and HDR brachytherapy or HDR brachytherapy alone posthysterectomy from 1985 to June 1993. Of these 225 patients, 82 received external beam radiotherapy and brachytherapy and 143 received brachytherapy alone. The HDR fraction size was 8.5 Gy prescribed to the mucosal surface; two fractions were given after external beam and four fractions if brachytherapy alone was used. The median follow-up was 6.9 years. The patients who received combined external beam and brachytherapy had higher stage and grade tumors. The survival outcome was similar for either group when matched for stage. Overall relapse-free survival at five years was 96% and 81%, respectively for brachytherapy alone and combined adjuvant therapy. Pelvic recurrence was seen in 2.7% of patients. Toxicity was more common with external beam radiotherapy and brachytherapy compared to brachytherapy alone (45.1% vs 23.1%, P = 0.003). However, moderate or severe toxicity was rare but again was more common in the combined radiotherapy group (8.5% vs 2.1%, P = 0.04). There was a non-significant trend to increased toxicity after lymphadenectomy and external beam radiotherapy compared with patients who did not have a staging lymphadenectomy prior to external beam radiotherapy (62% vs 38%, P = 0.16). Adjuvant radiotherapy can be individualized and be based upon the information provided by the pathological specimens, which excluded external beam radiotherapy if a lymphadenectomy was performed and there was no evidence of extra-uterine disease. This study found more toxicity associated with adjuvant radiotherapy compared with other studies, but this may reflect different reporting criteria. There was more toxicity related to external beam radiotherapy and brachytherapy compared to brachytherapy alone. The two HDR brachytherapy protocols used in this series appear effective and safe.

Transformation of Candida oleophila and survival of a transformant on orange fruit under field conditions

Histidine auxotrophs of wild-type strain I-182 of Candida oleophila, produced using ethyl methanesulfonate, were transformed with plasmids containing the HIS3, HIS4 and HIS5 genes of Saccharomyces cerevisiae. Histidine auxotrophy was complemented by the HIS5 gene of S. cerevisiae. Stability of the transformants under non-selective conditions and DNA gel-blot analysis suggested that the transforming DNA had integrated into the C. oleophila genome. There were no detectable physiological differences between the wild-type and the transformants. The biological control ability of C. oleophila was not affected by the transformation. A genetically marked transformant (with a beta-glucuronidase gene) colonized wounds on oranges, and its population increased under field conditions. The identity of the genetically marked transformant was established by PCR-amplification of a portion of the beta-glucuronidase gene.

Safe mobilization of normal progenitors in advanced chronic myeloid leukemia with intensive chemotherapy and granulocyte-colony stimulating factor

Twenty-one patients with advanced chronic myeloid leukemia (late chronic phase (n = 8), accelerated phase (n = 11) and blast crisis (n = 2)) were treated with idarubicin, cytarabine, and etoposide followed by G-CSF and subsequent collection of peripheral blood progenitor cells in the early recovery phase. Treatment was reasonably well tolerated with no deaths or intensive care admissions. Despite the advanced phase of disease and heavy pretreatment with cytotoxics and interferon-alfa, 11 of 21 patients (52%) achieved a cytogenetic response. Of the nine major cytogenetic responses (complete (n = 3) and partial (n = 6)), seven achieved adequate progenitor collections for consideration for autologous transplantation. The only predictor of response was disease duration (P = 0.02). With a median follow-up of 1171 days from treatment it appears unlikely that G-CSF contributed to disease progression. Survival post-IcE was predicted by disease stage (P = 0.0001). Intensive chemotherapy followed by G-CSF allowed adequate yields of predominantly Philadelphia chromosome negative progenitor cells to be obtained from one-third of patients with advanced CML.

High-dose-rate brachytherapy alone post-hysterectomy for endometrial cancer

PURPOSE

To evaluate the outcome of post-hysterectomy adjuvant vaginal high-dose-rate (HDR) brachytherapy.

METHODS AND MATERIALS

A retrospective analysis was performed on a series of 143 patients with endometrial cancer treated with HDR brachytherapy alone post-hysterectomy from 1985 to June 1993. Of these patients, 141 received 34 Gy in four fractions prescribed to the vaginal mucosa in a 2-week period. The median follow-up was 6.9 years. Patients were analyzed for treatment parameters, survival, local recurrence, distant relapse, and toxicity.

RESULTS

Five-year relapse free survival and overall survival was 100% and 88% for Stage 1A, 98% and 94% for Stage IB, 100% and 86% for Stage IC, and 92% and 92% for Stage IIA. The overall vaginal recurrence rate was 1.4%. The overall late-toxicity rate was low, and no RTOG grade 3, 4, or 5 complications were recorded.

CONCLUSION

These results are similar to reported international series that have used either low-dose-rate or HDR brachytherapy. The biological effective dose was low for both acute and late responding tissues compared with some of the HDR brachytherapy series, and supports using this lower dose and possibly decreasing late side-effects with no apparent increased risk of vaginal recurrence.

A method for studying the population dynamics of Candida oleophila on oranges in the grove, using a selective isolation medium and PCR technique

Populations of the biological control agent Candida oleophila on fruit in an orange grove were monitored by plating fruit washes and peel homogenates on a selective medium, followed by PCR analysis of DNA from yeast colonies resembling C. oleophila. The C. oleophila transformant ADGus-10 formed colonies on a selective medium that suppressed the development of 99% of the filamentous fungi and the indigenous yeasts, Aureobasium (a yeast-like fungus) and Rhodotorula. Only 6-8 indigenous yeasts/cm2 fruit surface gave rise to colonies that resembled C. oleophila on the selective medium. The identity of the C. oleophila transformant colonies was verified by PCR analysis of yeast DNA. The presence of a 599-bp band in the PCR product primed by beta-glucuronidase gene primers, confirmed the identity of C. oleophila transformant ADGus-10. Colony-forming units of C. oleophila were recovered efficiently from fortified washes of the fruit surface and from homogenates of wounds excised from fruit sprayed in the grove with C. oleophila.

Collection, tumor contamination, and engraftment kinetics of highly purified hematopoietic progenitor cells to support high dose therapy in multiple myeloma

Unfractionated peripheral blood stem cell (PBSC) grafts contain measurable quantities of myeloma cells and are therefore a potential source of relapse posttransplantation. In contrast, fluorescence-activated cell sorting (FACS)-sorted CD34+ Thy1+ Lin- peripheral blood cells are substantially enriched for stem cell activity, yet contain virtually no clonal myeloma cells. A study was performed in patients with symptomatic myeloma, who had received 12 months or less of preceding standard chemotherapy, to evaluate the feasibility of large scale purification of primitive hematopoietic stem cells in order to study engraftment kinetics posttransplantation and the degree of tumor cell contamination of this cell population, based on polymerase chain reaction (PCR) analysis for the patient-specific complementarity-determining region III (CDR III). PBSC were mobilized with high dose cyclophosphamide and granulocyte-macrophage colony-stimulating factor (GM-CSF). A combination of elutriation and chemical lysis was used to deplete PBSC collections of monocytes, granulocytes, erythrocytes, and platelets. Subsequently, CD34+ Thy1+ Lin- progenitor cells were purified with high speed cell sorting. Of the 10 evaluable patients, nine met the required minimum criteria of >/=7.2 x 10(5) cells/kg to support tandem transplants. After high dose melphalan (200 mg/m2) eight engrafted successfully, although granulocyte (absolute neutrophil count [ANC] >0.5 x 10(9)/L, 16 days) and platelet recovery (platelets > 50 x 10(9)/L, 39 days) was substantially delayed when compared with unmanipulated PBSC grafts; one patient required infusion of a reserve graft because of lack of evidence of engraftment by day +28. Three patients proceeded to a second graft with high dose melphalan and total body irradiation; two required infusion of a reserve graft and both died of infectious complications; one showed delayed, but complete, engraftment after this myeloablative regimen. Two of the nine evaluable patients attained a clinical complete remission (CR). The grafts from three patients were tested for tumor contamination and contained no detectable clonal myeloma cells. Larger quantities of purified cells may be required to resolve the problem of delayed engraftment.

Cougar attacks on children: injury patterns and treatment

PURPOSE

Cougar attacks on humans appear to be on the rise. A review of all attacks on children was performed to determine the method of attack and injury patterns so that a treatment regimen as well as possible preventative measures could be determined.

METHODS

A review of all attacks, including attacks on children, was performed, including three recent attacks treated at our institution. Situation, adult supervision, patient age, injuries recorded, survival, and mode of attack, if known, were reviewed.

RESULTS

There were 50 documented attacks on children with a 25% fatality rate. Most children were not alone at the time of the attack (92%), and in many instances adult supervision was present or nearby. Severe head and neck lacerations along with puncture wounds were the most common injury. Examples of typical cervical injuries include a nonfatal vertebral artery injury, phrenic nerve injury, a fatal internal carotid artery injury, and a fatal cervical spine injury. The cougar was rabid in two cases. Pasteurella resulted in late infections in two patients.

CONCLUSIONS

Based on the pattern of injuries, the authors recommend aggressive evaluation for occult cervical injuries as well as surgical debridement. Antibiotics should cover oropharyngeal flora including Pasteurella multocida. Rabies prophylaxis is indicated. Adult supervision in wilderness areas is not necessarily protective.

Preclinical antitumor activity of an antibody against the leukocyte antigen CD48

We have evaluated the antitumor activity of a murine antibody (IgG2a) against the leukocyte antigen CD48. CD48 is expressed on T and B lymphocytes, monocytes, and a wide range of lymphoid malignancies. To assess the therapeutic potential of an anti-CD48 antibody, we established a reproducible model of human B-cell (Raji) leukemia/lymphoma in C.B17/scid mice, where untreated mice develop hind leg paralysis due to tumor engraftment. Using this model, the murine anti-CD48 antibody HuLy-m3 was shown to mediate a strong in vivo antitumor effect. Long-term survival (>1 year) of scid mice was obtained after treatment with three 200-microg i.v. doses of anti-CD48 antibody on days 0, 2, and 4 after i.v. injection of tumor cells. In contrast, mice treated with an isotype control antibody developed hind leg paralysis after 34 +/- 3 days. A strong antitumor response was still observed when a dose of 20 microg of HuLy-m3 antibody was used. During preclinical investigations, we also examined a number of properties of the CD48 antigen. CD48 is present at high levels on the surface of T and B cells, but most (>95%) CD34-positive cells do not express CD48. Anti-CD48 antibodies are maintained on the surface of antigen-positive cells for extended periods (>24 h). These properties suggest that anti-CD48 antibodies may be useful in the treatment of a number of diseases including lymphoid leukemias and lymphomas.

A comparison of the pattern of interstitial pneumonitis following allogeneic bone marrow transplantation before and after the introduction of prophylactic ganciclovir therapy in 1989

A comparison was made of the pattern of interstitial pneumonitis (IP) following allogeneic bone marrow transplantation before and after the introduction of ganciclovir prophylaxis to minimize the risk of cytomegalovirus (CMV) disease in the St Vincent's Hospital bone marrow transplant program in 1989. A total of 456 recipients of allogeneic transplants were included. 280 received no prophylactic ganciclovir while 176 received prophylactic ganciclovir. The overall incidence of interstitial pneumonitis dropped from 19.6 to 12.5% (P = 0.03) and this was primarily due to a reduction in the incidence of CMV-IP which fell from 12.9 to 1.7% (P < 0.0005). The incidence of idiopathic IP was not different between the two groups (6.3 vs 3.2%), nor was the incidence of Pneumocystis carinii pneumonia (2.9 and 0.6%). Prophylactic ganciclovir has thus had a significant impact in reducing both the overall incidence of IP and specifically cytomegalovirus IP in allogeneic marrow transplant recipients. The most common form of IP in patients given prophylactic ganciclovir is now idiopathic interstitial pneumonitis.