Changes to country-specific hepatitis A travel vaccination recommendation for UK travellers in 2017-responding to a vaccine shortage in the national context

OBJECTIVES

A routine review of hepatitis A travel vaccination recommendations was brought forward in June 2017 due to hepatitis A vaccine shortages and a concurrent outbreak in men who have sex with men (MSM). There were three objectives: first, to document the review process for changing the recommendations for the UK travellers in June 2017. Second, to study the impact of these changes on prescribing in general practice in 2017 compared with the previous 5 years. Third, to study any changes in hepatitis A notifications in June-October 2017 compared with the previous 5 years.

STUDY DESIGN

This is an observational study.

METHODS

Travel vaccination recommendations for countries with either low-risk (<20%) or high-risk (>90%) status according to child hepatitis A seroprevalence were not changed. A total of 67 intermediate-risk countries with existing recommendations for most travellers and with new data on rural sanitation levels were shortlisted for the analysis. Data on child hepatitis A seroprevalence, country income status, access to sanitation in rural areas and traveller volumes were obtained. Information about the vaccine supply was obtained from Public Health England. Changes to the existing classification were made through expert consensus, based on countries' hepatitis A seroprevalence, sanitation levels, level of income, volume of travel and hepatitis A traveller cases. Data on the number of combined and monovalent hepatitis A-containing vaccines prescribed in England, 2012-2017, were obtained from the National Health Service Business Service Authorities. The number of monthly prescriptions for January-September 2017 was compared with the mean number of prescriptions for the same month in the previous 5 years (t-test, α = 5%, df = 4). The number of hepatitis A cases notified in June-October 2017 not related to the MSM outbreak was compared with the number of notifications in the same months in previous years.

RESULTS

A total of 36 countries were downgraded based on good access (80+% of population) to sanitation in rural areas and the intermediate-risk status in terms of child hepatitis A seroprevalence. For these countries, vaccination would only be recommended to travellers staying long term, visiting friends and relatives or staying in areas without good sanitation. There was a significant decline in hepatitis A vaccine prescriptions in June-September 2017, and there was no increase in the number of notifications.

CONCLUSIONS

Hepatitis A vaccination recommendations for travel were revised in 2017 following a systematic approach to maintain continuity of supply after a hepatitis A vaccine shortage and increased hepatitis A vaccine demand related to a large outbreak. Improved access to good sanitation in rural areas and low seroprevalence estimates among children have led to 36 countries to no longer require vaccination for most travellers. These changes do not seem to have impacted on hepatitis A notifications in England, although further research will be needed to quantify the impact more precisely.

Validation and deployment of the first Lidar based weather observation network in New York State: The NYS MesoNet Project

The number and quality of atmospheric observations used by meteorologists and operational forecasters are increasing year after year, and yet, consistent improvements in forecast skill remains a challenge. While contributing factors involving these challenges have been identified, including the difficulty in accurately establishing initial conditions, improving the observations at regional and local scales is necessary for accurate depiction of the atmospheric boundary layer (below 2km), particularly the wind profile, in high resolution numerical models. Above the uncertainty of weather forecasts, the goal is also to improve the detection of severe and extreme weather events (severe thunderstorms, tornadoes and other mesoscale phenomena) that can adversely affect life, property and commerce, primarily in densely populated urban centers.

This paper will describe the New York State Mesonet that is being deployed in the state of New York, USA. It is composed of 126 stations including 17 profiler sites. These sites will acquire continuous upper air observations through the combination of WINDCUBE Lidars and microwave radiometers. These stations will provide temperature, relative humidity & “3D” wind profile measurements through and above the planetary boundary layer (PBL) and will retrieve derived atmospheric quantities such as the PBL height, cloud base, momentum fluxes, and aerosol & cloud optical properties. The different modes and configurations that will be used for the Lidars are discussed. The performances in terms of data availability and wind accuracy and precision are evaluated. Several profiles with specific wind and aerosol features are presented to illustrate the benefits of the use of Coherent Doppler Lidars to monitor accurately the PBL.

The impact of new national guidance for the public health management of enteric fever in England

OBJECTIVES

New guidance was published in England in February 2012 to support the public health management of enteric fever and reduce the risks of secondary transmission. The new guidance was evaluated to assess: STUDY DESIGN: Quantitative and qualitative evaluation of the implementation of new public health guidance.

METHODS

A qualitative review of all non-travel-related cases from February 2010 to January 2014 to compare the risk of secondary transmission before and after the guidance introduction; an audit of clearance sampling for each case and their contacts reported in London from February 2012-January 2015 to compare with a previous London audit; and an online user survey in November 2014.

RESULTS

The proportions of non-travel cases reported before and after the introduction of the new guidance were similar, 6% in 2010-2012 compared to 7% in 2012-2014 (P = 0.33). There was a 32% reduction in the number of clearance samples required for cases and the estimated period of exclusion from work or school was reduced from 54 days to 16 days. Compliance in case clearance improved from 53% to 90% and contact screening compliance improved from 42% to 80%. The targeted screening of contacts led to a significantly higher positive yield (3.6% from 1.5%, P = 0.003). All symptomatic co-travellers presented to a healthcare professional, suggesting that screening could be restricted to those in risk groups for transmission. Feedback from users highlighted additional areas, such as management of large organised groups of co-travellers and those diagnosed abroad, which has informed the update of the national guidance.

CONCLUSIONS

The new guidance has not led to an increase in secondary transmission of enteric fever in England and findings have been used to inform an update of the guidance. The new guidance also represents a reduced burden of investigation and thus a likely reduced cost to patients, healthcare professionals, laboratories and environmental health officers.

High frequency jet ventilation for motion management during ablation procedures, a narrative review

BACKGROUND

High frequency jet ventilation (HFJV) is a method of ventilation that has gained renewed interest over the recent years as it can reduce organ movement to near static conditions, thus enhancing surgical precision in minimal invasive procedures, for example, ablation procedures for atrial fibrillation and solid organ tumours. The aim of this review was to create a summary of the current evidence concerning the clinical use of HFJV for ablative procedures.

METHOD

PubMed was searched for the key words high frequency ventilation and ablation January 1990-December 2016.

RESULT

The search initially identified 34 papers, 14 met the inclusion criteria. Articles in other languages than English (n = 1), comments regarding other articles (n = 4) and articles that did not include HFJV or ablative procedures (n = 15) were excluded. Two articles were added from references in papers included from the primary search. Sixteen studies were finally included in the review; four updates/reviews and 12 papers with results from studies of HFJV on humans, with a total of 889 patients; 498 patients ventilated with HFJV and 391 controls. There were no randomised studies. The overall scientific quality of the studies was low.

CONCLUSION

There is a lack of well-designed studies evaluating HFJV during ablation procedures. The available information, while sparse, supports the effect of less tissue movement, resulting in better surgical precision and outcome; such as shorter procedural time, fewer shock waves (ESWL) and less recurrence of atrial fibrillation. Randomised controlled studies are needed in this promising area of research to prove its superiority to standard ventilation.

Insensitivity to pain induced by a potent selective closed-state Nav1.7 inhibitor

Pain places a devastating burden on patients and society and current pain therapeutics exhibit limitations in efficacy, unwanted side effects and the potential for drug abuse and diversion. Although genetic evidence has clearly demonstrated that the voltage-gated sodium channel, Nav1.7, is critical to pain sensation in mammals, pharmacological inhibitors of Nav1.7 have not yet fully recapitulated the dramatic analgesia observed in Nav1.7-null subjects. Using the tarantula venom-peptide ProTX-II as a scaffold, we engineered a library of over 1500 venom-derived peptides and identified JNJ63955918 as a potent, highly selective, closed-state Nav1.7 blocking peptide. Here we show that JNJ63955918 induces a pharmacological insensitivity to pain that closely recapitulates key features of the Nav1.7-null phenotype seen in mice and humans. Our findings demonstrate that a high degree of selectivity, coupled with a closed-state dependent mechanism of action is required for strong efficacy and indicate that peptides such as JNJ63955918 and other suitably optimized Nav1.7 inhibitors may represent viable non-opioid alternatives for the pharmacological treatment of severe pain.

Fate of necrotic volume after microwave ablation of multiple liver metastases

BACKGROUND/AIMS

The aim of this study was to find the rate of shrinkage of necrosis and time of peak ablation volume after multiple microwave ablations in the treatment of multiple liver metastases of colorectal cancer. These factors are not known and are important in evaluation of treatment and identification of local recurrence, as microwave treatment is becoming more used thanks to improved technology in diagnostics and interventional therapy.

METHODOLOGY

A retrospective analysis of non-cirrhotic patients with multiple liver only metastases of colorectal cancer, not suited for resection for this reason. Patients were selected for palliative microwave treatment at a liver multidisciplinary team conference. 68 ablations were made in six patients. Ablation volume was analysed with repeated imaging and computer analyses.

RESULTS

The ablation volume peeks after 5-7 days where after reduction of the necrosis in the liver occurs logarithmically with a 60% reduction of ablation volume after 100 days and 80% after a year.

DISCUSSION

Liver regeneration after microwave ablations occurs at a constant logarithmic rate after an initial expansion of the ablation volume during the first five days. Evaluation of ablation volume in comparison to tumour volume must take this into account so that follow-up imaging is properly timed.

Chikungunya outbreak in the Caribbean region, December 2013 to March 2014, and the significance for Europe

On 6 December 2013, two laboratory-confirmed cases of chikungunya without a travel history were reported on the French part of the Caribbean island of Saint Martin, indicating the start of the first documented outbreak of chikungunya in the Americas. Since this report, the virus spread to several Caribbean islands and French Guiana, and between 6 December 2013 and 27 March 2014 more than 17,000 suspected and confirmed cases have been reported. Further spread and establishment of the disease in the Americas is likely, given the high number of people travelling between the affected and non-affected areas and the widespread occurrence of efficient vectors. Also, the likelihood of the introduction of the virus into Europe from the Americas and subsequent transmission should be considered especially in the context of the next mosquito season in Europe. Clinicians should be aware that, besides dengue, chikungunya should be carefully considered among travellers currently returning from the Caribbean region.

Clinical trial: 2-L polyethylene glycol-based lavage solutions for colonoscopy preparation - a randomized, single-blind study of two formulations

BACKGROUND

The 2-L polyethylene glycol (PEG) lavage solutions provide efficacy similar to that of standard 4-L PEG formulations in spite of the reduced volume. The comparative efficacy and tolerability of two formulations of 2-L PEG solution remain unknown.

AIMS

To assess the efficacy, safety and tolerability of PEG + Bis compared with PEG + Asc, and to study the effect of bowel cleansing quality on adenoma detection rates.

METHODS

Patients were randomized to receive either 2-L PEG with ascorbic acid (PEG + Asc) or 2-L PEG plus bisacodyl 10 mg (PEG + Bis). The primary endpoint was overall colon cleansing score, assessed by blinded investigators using a validated four-point scale. Secondary endpoints included adenoma detection rate, patient tolerability and compliance and adverse events.

RESULTS

Fifty-two patients received PEG + Asc and 55 patients received PEG + Bis. Overall colon cleansing scores (+/-s.d.) were 1.40 +/- 0.69 and 1.75 +/- 0.70 (P < 0.003) in the PEG + Asc and PEG + Bis groups, respectively. Excellent and good ratings were recorded in 69% and 23% receiving PEG + Asc compared to 38% and 51% (P = 0.01) of patients receiving PEG + Bis. More adenomas were detected in colonoscopies performed with PEG + Asc (39%) than in those performed with PEG + Bis (20%) (P = 0.04). Patient tolerability and safety were similar with both preparations.

CONCLUSION

The use of PEG + Asc resulted in better colon cleansing and higher adenoma detection rates compared with PEG + Bis.

Transcatheter coil embolisation: a novel definitive treatment option for intralobar pulmonary sequestration

Pulmonary sequestrations have been conventionally treated surgically with removal of the tissue mass and ligation of its feeding vessels. There is established evidence to support the use of transcatheter arterial coil embolisation as an effective definitive treatment option for extralobar sequestration especially in the paediatric literature describing good long-term clinical outcomes. We present a case of an adult with intralobar sequestration in whom the diagnosis was established with multi-detector computed tomography (MDCT) and in whom transcatheter arterial coil embolisation was successfully performed as a definitive treatment option to support the growing body of evidence of transcatheter arterial coil embolisation as a safe and effective treatment option for both form of pulmonary sequestrations.

Bariatric surgery reduces mortality in Swedish men

BACKGROUND

Mortality is lower in obese patients who have undergone surgery for obesity than in those who have not. The majority of patients in these studies have been women. Perioperative mortality is known to be higher among men, and this may counterbalance the survival advantage seen after surgery. This cohort study compared mortality among operated obese patients, non-operated obese patients and a general control cohort of men.

METHODS

The study was based on record linkage between Swedish registries. An operated obese, a non-operated obese and a general control cohort were created. The two non-operated cohorts were assigned pseudosurgery dates. Data regarding preoperative and postoperative morbidity were collected, as well as mortality data.

RESULTS

Hazard ratios were calculated for mortality between the cohorts adjusting for preoperative morbidity and age. Comparison of all-cause mortality for the obese surgical and non-surgical cohorts gave an adjusted mortality risk of 0.7 (95 per cent confidence interval (c.i.) 0.5 to 1.0) (P = 0.039); the adjusted mortality risk was 1.5 (95 per cent c.i. 1.1 to 2.0) (P = 0.011) when the obese surgical cohort was compared with the general control cohort.

CONCLUSION

Bariatric surgery reduces overall mortality in obese men.

Storage of strain-specific rat blood limits cerebral tissue oxygen delivery during acute fluid resuscitation

BACKGROUND

The effect of blood storage on tissue oxygen delivery has not been clearly defined. Some studies demonstrate reduced microvascular oxygen delivery, whereas others do not. We hypothesize that storage of rat blood will limit its ability to deliver oxygen to cerebral tissue.

METHODS

Anaesthetized rats underwent haemorrhage (18 ml kg(-1)) and resuscitation with an equivalent amount of fresh or 7 day stored strain-specific whole blood. Arterial blood gases, co-oximetry, red cell counts and indices, and blood smears were performed. Hippocampal tissue oxygen tension (PBr(O2)), regional cerebral blood flow (rCBF), and mean arterial pressure (MAP) were measured before and for 60 min after resuscitation (n=6). Data [mean (SD)] were analysed by anova.

RESULTS

After 7 days, there was a significant reduction in pH, Pa(O2), an increase in Pa(CO2), but no detectable plasma haemoglobin in stored rat blood. Stored red blood cell morphology demonstrated marked echinocytosis, but no haemolysis in vitro. MAP and PBr(O2) in both groups decreased after haemorrhage. Resuscitation with stored blood returned MAP [92 (SD 16) mm Hg] and PBr(O2) [3.2 (0.7) kPa] to baseline, whereas rCBF remained stable [1.2 (0.1)]. Resuscitation with fresh blood returned MAP to baseline [105 (16) mm Hg] whereas both PBr(O2) [5.6 (1.5) kPa] and rCBF [1.9 (0.4)] increased significantly (P<0.05 for both, relative to baseline and stored blood group). There was no evidence of haemolysis in vivo.

CONCLUSIONS

Although resuscitation with stored blood restored cerebral oxygen delivery to baseline, fresh blood produced a greater increase in both PBr(O2) and rCBF. These data support the hypothesis that storage limits the ability of RBC to deliver oxygen to brain tissue.

The level of matrix metalloproteinase-2 in donor plasma strongly correlates with post-transfusion recovery of stored platelet concentrates

BACKGROUND AND OBJECTIVE

A simple test accurately predicting post-transfusion recovery of stored platelet concentrates (PCs) is needed.

MATERIALS AND METHODS

Matrix metalloproteinase-2 (MMP-2) was determined in fresh-frozen plasma of normal donors using enzyme-linked immunosorbent assay (ELISA)-based assay. Post-transfusion recovery of human PCs was determined in rabbits with an inhibited reticuloendothelial system by flow cytometry.

RESULTS

We demonstrated a strong positive (r = 0.91) and highly significant (P = 0.0015) correlation between the concentration of MMP-2 in plasma of normal donors and post-transfusion recovery of PCs stored for 5 days at 22 degrees C under standard blood banking conditions. A higher level of donor plasma MMP-2 is associated with improved recovery of transfused platelets.

CONCLUSION

These observations suggest that pre-transfusion MMP-2 assay of donor's plasma may be a predictor of post-transfusion recovery of PCs. However, the usefulness of this assay should be elucidated in clinical transfusion settings.

Monoclonal platelet antigen capture assays (MAIPA) and reagents: a statement

This statement concerning the monoclonal-specific immobilization of platelet antigens (MAIPA) has been written on behalf of the International Society of Blood Transfusion--Working Party on Platelet Immunology. The MAIPA technique is considered as the gold standard reference technique in platelet immunology. The assay performed with reagents labelled for 'research only' is acceptable as long as it is regularly evaluated by participation of laboratories in national or international workshops held with reference laboratories.

Supra-Tenon's capsule placement of a single-plate Molteno implant

AIM

To describe clinical results of a new technique for inserting Molteno implants in a supra-Tenon's capsule location.

DESIGN

Prospective interventional case study.

PARTICIPANTS

19 patients, 18 of whom had suffered previous filter or glaucoma implant failure. Seventeen had open-angle glaucoma, and two had neovascular glaucoma. Seventeen patients were black and two were Asian.

INTERVENTION

All patients underwent supra-Tenon's capsule placement of a single-plate Molteno implant. Goldmann applanation tensions and Snellen visual acuities were determined before the operation and at the last follow-up visit. The numbers of preoperative and postoperative adjunctive drugs were compared before and after surgery.

MAIN OUTCOME MEASURES

Success was defined as intraocular pressure < or = 18 mm Hg with or without anti-glaucoma drugs.

RESULTS

Mean age was 62 years. Mean pressure before and after surgery was 31 and 16 mm Hg, respectively. Mean follow-up was 22 months (range 12-48). Vision returned to within 2 lines of preoperative vision, except in one patient who lost light perception. Surgery was regarded as a failure in four patients, including both patients with neovascular glaucoma. The difference between the median number of drugs used before (three) and after (one) the operation was significant (p<0.001). Complications were minimal, characterised by small choroidal effusions in three patients; all resolved spontaneously.

CONCLUSION

Supra-Tenon's capsule placement of Molteno implants in eyes with previously failed glaucoma surgery is an effective method for controlling intraocular pressure.

A continuum-based outcome approach to measuring performance in HIV/AIDS case management

This methods paper is third in a series addressing client outcomes in HIV/AIDS case management. After introducing earlier work the authors outline their effort to consolidate numerous discrete outcome measures and to establish each outcome indicator along a continuum scale that can be self-abstracted by HIV/AIDS service providers. The paper includes in-depth discussion of challenges and benefits derived from this type of outcome measurement process. Key lessons learned from a pilot study are offered for those considering development of similar client outcomes assessment programmes. The paper concludes with several opportunities for future research for those desiring to work in this relatively uncharted domain.

Higher thrombin concentrations are required to induce platelet apoptosis than to induce platelet activation

Primarily known as an inducer of blood coagulation and platelet activation, thrombin also triggers platelet apoptosis. This study demonstrated that the platelet activation response is much more sensitive than platelet apoptosis to thrombin treatment. Thrombin concentrations of 0.5-1 nmol/l activated almost all platelets, but only a small fraction underwent apoptosis, suggesting that at these relatively low thrombin concentrations, platelets may perform haemostasis but not be involved in programmed cell death. At high thrombin concentrations of 10-100 nmol/l, generated during blood coagulation, 30-40% of platelets became apoptotic, indicating that hypercoagulable states may be associated with increased numbers of apoptotic platelets.

Persistence of procoagulant surface expression on activated human platelets: involvement of apoptosis and aminophospholipid translocase activity

BACKGROUND

Activated platelets express a procoagulant surface when the asymmetric distribution of membrane phospholipids is scrambled, leading to phosphatidylserine (PS) exposure. PS expression, associated with apoptosis in nucleated cells, would be expected to be reversed by aminophospholipid translocase (APLT) activity.

OBJECTIVE

To determine whether the procoagulant surface of activated platelets persists after it forms; to examine whether PS expression on platelets is associated with loss of mitochondrial inner membrane potential (DeltaPsi(m)), a hallmark of apoptosis; and to investigate the role of APLT in persistence of PS expression.

METHODS

Platelets were stimulated with thrombin, collagen, a combination of both, or the Ca(2+)-ionophore A23187. Up to 4 h after activation, procoagulant surface expression was measured by annexin A5 binding by flow cytometry and by a prothrombinase assay. Flow cytometry was also used to measure PS expression concurrently with DeltaPsi(m) collapse, using CMXRos. APLT activity in annexin A5-negative and -positive platelets was measured flow cytometrically as the percent of 1-palmitoyl-2-[6-[(7-nitro-2-1,3-benzoxadiazol-4-yl)amino]caproyl]-sn-glycero-3-phosphatidylserine (NBD-PS) translocated from the outer to the inner membrane leaflet.

RESULTS AND CONCLUSIONS

Procoagulant surface expression on activated platelets persisted in vitro for at least 4 h; if such persistence occurs in vivo, there are important implications for the propagation of thrombosis. With the physiological stimuli, only 10-20% of the activated platelets expressed PS on their surface, and of these, only a portion exhibited DeltaPsi(m) collapse, indicating that PS expression can be associated with platelet apoptosis, but can also occur independently. APLT activity was very low in the PS-expressing platelet subpopulation for up to 4 h after activation, indicating that the persistence of a procoagulant surface may be attributed, at least in part, to this reduced APLT activity.

Thrombin-triggered platelet apoptosis

BACKGROUND

Thrombin is primarily known as a coagulation factor and as an inducer of platelet activation and aggregation. It has been reported that thrombin modulates apoptosis of nucleated cells.

OBJECTIVES

The current study investigated whether thrombin can affect apoptosis in anucleated human platelets.

METHODS

Using flow cytometry, we studied platelet apoptosis at the single-cell level, analyzing markers of mitochondrial and cytoplasmic apoptosis. Western blotting was also employed, in addition to flow cytometry, for determining the expression of Bcl-2 family proteins.

RESULTS

We found that human alpha-thrombin induced four key manifestations of apoptosis in human platelets: (i) mitochondrial inner transmembrane potential (DeltaPsi m) depolarization; (ii) strong expression of pro-apoptotic Bax and Bak proteins but only weak expression of anti-apoptotic Bcl-2 protein; (iii) caspase-3 activation; and (iv) phosphatidylserine (PS) exposure.

CONCLUSIONS

This study demonstrates that, aside from its 'classical' function as an inducer of platelet activation, thrombin can trigger platelet apoptosis, where it acts as a death ligand. These data indicate that thrombin triggers platelet apoptosis by impacting on several intracellular apoptotic targets, including shifting the balance between Bcl-2 regulatory proteins in a pro-apoptotic direction, depolarizing the inner mitochondrial membrane, activating the executioner caspase-3, and stimulating aberrant exposure of PS on the platelet surface.

Fibrinogen and von Willebrand factor-independent platelet aggregation in vitro and in vivo

BACKGROUND

Fibrinogen (Fg) has been considered essential for platelet aggregation. However, we recently demonstrated formation of occlusive thrombi in Fg-deficient mice and in mice doubly deficient for Fg and von Willebrand factor (Fg/VWF(-/-)).

METHODS AND RESULTS

Here we studied Fg/VWF-independent platelet aggregation in vitro and found no aggregation in citrated platelet-rich plasma of Fg/VWF(-/-) mice. Surprisingly, in Fg/VWF(-/-) plasma without anticoagulant, adenosine diphosphate induced robust aggregation of Fg/VWF(-/-) platelets but not of beta(3)-integrin-deficient (beta(3) (-/-)) platelets. In addition, beta(3) (-/-) platelets did not significantly incorporate into thrombi in Fg/VWF(-/-) mice. This Fg/VWF-independent aggregation was blocked by thrombin inhibitors (heparin, hirudin, PPACK), and thrombin or thrombin receptor activation peptide (AYPGKF-NH(2)) induced aggregation of gel-filtered Fg/VWF(-/-) platelets in 1 mm Ca(2+) PIPES buffer. Notably, aggregation in PIPES buffer was only 50-60% of that observed in Fg/VWF(-/-) plasma. Consistent with the requirement for thrombin in vitro, hirudin completely inhibited thrombus formation in Fg/VWF(-/-) mice. These data define a novel pathway of platelet aggregation independent of both Fg and VWF. Although this pathway was not detected in the presence of anticoagulants, it was observed under physiological conditions in vivo and in the presence of Ca(2+)in vitro.

CONCLUSIONS

beta(3) integrin, thrombin, and Ca(2+) play critical roles in this Fg/VWF-independent aggregation, and both plasma and platelet granule proteins contribute to this process.

A provincial program of blood conservation: The Ontario Transfusion Coordinators (ONTraC)

PURPOSE

Although often life-saving, blood transfusions are associated with significant risk to the patient and escalating costs to the blood system and hospital. Transfusions are often given unnecessarily. Blood conservation represents the use of alternatives to transfusion. The ONTraC program attempts to enhance transfusion practice outside the blood transfusion laboratory, promote blood conservation in surgery patients, and reduce allogeneic red cell use.

METHODS

In the first such large scale program, funding was obtained from the Ontario MOHLTC for a Transfusion Coordinator in 23 Ontario hospitals selected based on blood utilization and geography. At specific time periods, detailed anonymized information was collected in a defined number of all consecutive patients admitted for the three designated surgical procedures: knee arthroplasty (N=approximately 1200 at each time point), abdominal aortic aneurysm (AAA; N=300 at each time) and coronary artery bypass graft (CABG) surgery (N=300 at each time point).

RESULTS

Considerable inter-institutional variation was observed in the proportion of patients and amount of blood transfused. At the 12 month analysis, most, although not all, hospitals had decreased use of allogeneic blood and there was an overall 24% reduction in blood use in patients undergoing knee surgery, 14% in AAA and 23% in CABG. In addition to reduction in proportion of patients transfused, transfused patients received fewer units of allogeneic blood. Patients who did not receive allogeneic transfusions had significantly lower postoperative infection rates (p<0.05) and length of stay (p<0.0001); multivariate analysis showed that allogeneic transfusion was an independent predictor of increased length of stay. Eighteen-month analysis indicates even greater reduction in allogeneic transfusion. The main measures of blood conservation employed were preoperative autologous donation and education, with recent increasing use of erythropoietin and the cell saver. These measures have been demonstrated to be very effective in avoiding allogeneic transfusion.

CONCLUSIONS

The ONTraC have become leaders locally, nationally and internationally in blood conservation. The reduction in allogeneic transfusion associated with the implementation of the ONTraC program represents important savings in costs associated with blood components, hospital stay and work in transfusion laboratories and nursing units, as well as enhancing patient satisfaction and safety.

Vitronectin stabilizes thrombi and vessel occlusion but plays a dual role in platelet aggregation

The role of vitronectin (Vn) in thrombosis is currently controversial; both inhibitory and supportive roles have been reported. To monitor directly the function of Vn in thrombotic events at the site of vascular injury, we studied Vn-deficient (Vn-/-) and wild-type (WT) control mice with two real-time intravital microscopy thrombosis models. In the mesenteric arteriole model, vessel injury was induced by ferric chloride. We observed unstable thrombi and a significantly greater number of emboli in Vn-/- mice. Vessel occlusion was also delayed and frequent vessel re-opening occurred. In the cremaster muscle arteriole model, vessel injury was induced by a nitrogen dye laser. We observed significantly fewer platelets, lower fibrin content, and unstable fibrin within the thrombi of Vn-/- mice. To define further the role of Vn in thrombus growth, we studied platelet aggregation in vitro. Consistent with our in vivo data, the second wave of thrombin-induced aggregation of gel-filtered platelets was abolished at a low concentration of thrombin in Vn-/- platelets. Interestingly, adenosine diphosphate (ADP)-induced platelet aggregation was significantly increased in Vn-/- platelet-rich plasma (PRP) and this effect was attenuated by adding purified plasma Vn. We also observed increased platelet aggregation induced by shear stress in Vn-/- whole blood. These data demonstrate that Vn is a thrombus stabilizer. However, in contrast to released platelet granule Vn which enhances platelet aggregation, plasma Vn inhibits platelet aggregation.

Triple heterozygosity in the integrin alphaIIb subunit in a patient with Glanzmann's thrombasthenia

We report triple heterozygosity in the integrin alpha(IIb) subunit in a 5-year-old Canadian girl with Glanzmann's thrombasthenia. The patient has a severe bleeding history possibly aggravated by low VWF suggestive of associated type 1 von Willebrand's disease. Platelet aggregation was absent or severely reduced for all physiologic agonists. Flow cytometry showed an approximately 4% residual surface expression of alpha(IIb)beta(3). Western blotting confirmed a low platelet expression of both subunits. PCR-SSCP and direct sequencing showed no abnormalities in the beta(3) gene, but revealed a G-->A transition at a splice site [IVS 19 (+1)] of exon 19 in the alpha(IIb) gene. Of maternal inheritance, the splice site mutation was associated with intermediate levels of alpha(IIb)beta(3) in carriers. Unexpectedly, two G-->A transitions were detected in exon 29 of the alpha(IIb) gene and led to V(951)-->M and A(958)-->T amino acid substitutions. Family studies using restriction enzymes showed that both exon 29 mutations were paternal in origin and cosegregated across three generations. Transient expression in which mutated alpha(IIb) was cotransfected with wild-type beta(3) in COS-7 cells showed that V(951)-->M gave a much reduced surface expression of alpha(IIb)beta(3) and a block in the maturation of pro-alpha(IIb). In contrast, the A(958) substitution appeared to be a novel polymorphism. Our studies highlight an unusual mixture of defects giving rise to severe bleeding in a child and describe the first pathological missense mutation affecting a C-terminal residue of the calf-2 domain of alpha(IIb).

Procoagulant surface exposure and apoptosis in rabbit platelets: association with shortened survival and steady-state senescence

BACKGROUND

The signal(s) for removal of senescent platelets from the circulation are not fully understood; phosphatidylserine (PS) expression on platelets and another marker of apoptosis, loss of mitochondrial inner membrane potential (DeltaPsim), have been implicated in platelet clearance.

OBJECTIVE

To investigate whether shortened platelet survival and steady-state platelet senescence are associated with increased surface exposure of PS and DeltaPsim collapse.

METHODS

Survival of in-vitro biotinylated rabbit platelets treated with thrombin or Ca(2+)-ionophore A23187 was tracked by flow cytometry after injection. Steady-state platelet senescence was investigated by infusing biotin to label a platelet cohort. PS expression and DeltaPsim of in-vitro biotinylated platelets and of the aging platelet cohort biotinylated in-vivo were measured by flow cytometry using annexin V-FLUOS and the DeltaPsim-sensitive dye CMXRos, respectively.

RESULTS

Although PS expression, DeltaPsim and survival of thrombin-degranulated platelets were similar to those of control platelets, increasing concentrations of A23187 caused increased surface exposure of PS and progressive shortening of platelet survival; only one-sixth of PS-expressing platelets also exhibited DeltaPsim loss. The cohort of senescent, biotinylated platelets remaining in the circulation at 96 h had increased exposure of PS and collapsed DeltaPsim; of the 17% of PS-expressing platelets, one-third did not exhibit DeltaPsim loss. There was also an increase in platelets with collapsed DeltaPsim but not expressing PS.

CONCLUSIONS

Platelets with shortened survival and senescent platelets have increased surface exposure of PS, that may be involved in their clearance. PS expression can occur independently of DeltaPsim collapse and conversely, in aged platelets, DeltaPsim loss can occur independently of PS expression.

The activity of the von Willebrand factor cleaving protease ADAMTS-13 in newborn infants

BACKGROUND

Unusually large von Willebrand factor (VWF) multimers have been observed in patients with thrombotic microangiopathies (TMA), and absence of the VWF cleaving protease ADAMTS-13 activity is considered to be involved in the etiology of TMA. Increased amounts of large multimers of VWF have also been identified in neonates.

OBJECTIVE

We assessed ADAMTS-13 activity in healthy neonates, children and adults to establish baseline levels.

PATIENTS AND METHODS

Cord blood was collected from 38 full-term newborns; venous samples were taken from 15 neonates on day 2-3 of life. Seventeen children, 24 healthy adults and seven patients with TMA were studied as well. ADAMTS-13 activity was quantified by the binding of the subjects' plasma VWF to collagen before and after enzyme activation. The multimer distribution of VWF was also determined.

RESULTS

Neonates and children had percentage ADAMTS-13 activity similar to adults. However, two groups were apparent in the cord blood samples: while 28/38 newborns had percentage activity within the normal range of healthy adults (102 +/- 3.0%), 10 had significantly lower percentage activity (53 +/- 1.1%; P < 0.0001) that normalized by day 2-3. The VWF multimer distribution was the same in all cord blood samples and was not different compared with children and adults. High-molecular-weight VWF multimers were significantly increased in the 2-3-day-old neonates and in TMA patients.

CONCLUSIONS

Although ADAMTS-13 activity was similar in neonates compared with adults, 26% of neonates had mildly reduced activity. Further studies are needed to investigate the complex interaction of VWF production and secretion with its size control by ADAMTS-13 in different age groups.

von Willebrand factor (VWF)-dependent human platelet activation: porcine VWF utilizes different transmembrane signaling pathways than does thrombin to activate platelets, but both require protein phosphatase function

The interaction between von Willebrand factor (VWF) and glycoprotein (GP) Ib results in platelet agglutination and activation of many signaling intermediates. To determine if VWF-dependent platelet activation requires the participation of pivotal transmembrane signaling pathways, we analyzed VWF-dependent platelet activation profiles following inhibition of several transmembrane signaling intermediates. This was accomplished using porcine VWF, which has been shown to interact with human GPIb independently of shear stress or ristocetin. Platelet alpha (CD62) and lysozomal granule release (CD63), microparticle formation, and platelet agglutination/aggregation were evaluated. The ability of signaling inhibitors to prevent VWF-dependent platelet activation was compared to their ability to inhibit thrombin-dependent activation. The results demonstrate that VWF-dependent platelet activation can occur independently of the activities of protein kinase C (PKC), wortmannin-sensitive phosphatidylinositide 3-kinase, and phospholipase C, as well as independently of elevations in the concentration of intracellular calcium. In sharp contrast, these transmembrane signaling intermediates are required for thrombin-dependent platelet activation. In addition, thrombin-dependent but not VWF-dependent platelet activation was associated with elevations in the concentration of intracellular calcium under the conditions used. The family of signaling intermediates which appeared to be pivotal for both thrombin- and VWF-dependent platelet activation were the protein tyrosine phosphatases and the serine/threonine phosphatases. It is concluded that thrombin-dependent platelet activation relies on the activation of several transmembrane signaling pathways, whereas VWF-dependent platelet activation is dependent upon the activity of protein phosphatases. Inhibition of these phosphatases in vivo may provide a novel therapeutic approach for treating VWF-dependent platelet disorders such as thrombotic thrombocytopenic purpura or arterial thrombosis.

Development and implementation of an HIV/AIDS case management outcomes assessment programme

The Case Management Section of the New York State Department of Health AIDS Institute coordinates the provision of case management services for people living with HIV/AIDS throughout the state. The Community Follow-Up Program (CFP), providing intensive case management for HIV-positive individuals and their families, operates under the auspices of the Case Management Section. This article focuses on a public/private outcomes assessment partnership, sponsored by the Case Management Section, and developed in conjunction with a team of CFP programme managers from across the state. The process used to develop outcome indicators and measures is described; challenges encountered along the way are detailed; and suggestions for other public/private partnerships are outlined. Results from two years of outcomes data collection are also presented. The article concludes that the inclusion of providers in the identification and measurement of desired outcomes can help overcome provider resistance to outcomes assessment and can help ensure that outcomes data are used to improve programme performance.

Gastric emptying and duodeno-gastro-oesophageal reflux in gastro-oesophageal reflux disease

BACKGROUND

Previous studies present conflicting results regarding relationship between gastric emptying and gastro-oesophageal reflux disease. Reflux of duodenal content to oesophagus is generally considered to be associated with more severe disease.

AIM

To assess presence of a gastric emptying disorder in persons with reflux of duodenal contents to oesophagus and to identify any correlation with gastric emptying and oesophageal motility.

METHODOLOGY

A total of 15 subjects with (B+) and 15 subjects without (B-) bile reflux to oesophagus determined by 24-hour bilirubin monitoring were studied with scintigraphic solid gastric emptying and 24-hour oesophageal manometry.

RESULTS

There was no difference in lag phase [median 23.7 (range 10.8-44.0) vs 24.6 (8.1-40.1) min], half emptying time [74.6 (48.0-93.6) vs 82.8 (54.4-153.9) min] or emptying rate [0.89 (0.59-1.34) vs 0.83 (0.36-1. 15)%/min] for B- and B+ subjects, respectively. In addition, there was no difference in emptying rate of gastric fundus between B- and B+ subjects. Subjects with bile reflux had less effective oesophageal contractions of oesophageal body [9.4(3.3-37)%] compared to subjects without bile reflux [32(19-47)%, p = 0.002]. However, there was no correlation between oesophageal motility and gastric emptying.

CONCLUSION

Results suggest that a gastric emptying disorder is a less likely contributing cause of bile reflux to the oesophagus, but bile reflux is associated with less effective oesophageal motility.

Anti-D (WinRho SD) treatment of children with chronic autoimmune thrombocytopenic purpura stimulates transient cytokine/chemokine production

Intravenous anti-D is often used in the treatment of autoimmune thrombocytopenic purpura (AITP), but little is known about its mechanisms of action. To investigate anti-D's potential in vivo mechanism(s) of action, a small group (N = 7) of children with chronic AITP was studied. The children initially received either 25 or 50 microg/kg of WinRho-SD in a four-cycle cross-over trial, and peripheral blood samples from the first and third cycles were assessed for cytokine levels at pre-treatment, 3 hr, 1 day, and 8 days post-treatment. Results showed that platelet counts significantly increased in all the children by day 8 post-treatment. Analysis of serum by ELISA showed that there was a significant but transient rise in both pro- and anti-inflammatory cytokine/chemokine levels (e.g., IL1RA, IL6, GM-CSF, MCP-1 alpha, TNF-alpha and MCP-1) by 3 hr post-treatment in both cycles which returned to baseline levels by 8 days post-treatment. These results suggest that anti-D administration may initially activate the RES in the form of cytokine/chemokine secretion, which is subsequently followed by an increase in platelet counts. It is possible that the induced cytokine/chemokine storm may have an effect on several physiological processes such as those mediating either adverse effects or potentially RES phagocytic activity.

Platelet activation and hypercoagulability following treatment with porcine factor VIII (HYATE:C)

Activation of platelets and coagulation in vivo was studied in nine patients with hemophilia A and inhibitors to human Factor VIII, prior to and following treatment with porcine Factor VIII (PFVIII; HYATE:C). In addition, six hemophiliac patients were similarly studied after treatment with recombinant Factor VIII (rFVIII). Platelet activation was also examined in vitro using porcine von Willebrand factor (PvWF)-enriched and PvWF-depleted fractions obtained by fractionation of PFVIII. Coagulation was assessed by measuring the concentrations of plasma prothrombin fragment 1+2 concentrations (prothrombinase generation) and Factor Xa-ATIII. Patients treated with PFVIII had significantly increased numbers of circulating platelets expressing CD62 and CD63 (markers of platelet activation) and annexin V (marker of platelet procoagulant activity) compared to patients treated with rFVIII; the former patients also demonstrated an increase in plasma coagulability after therapy. In in vitro experiments it was observed that the platelet-activating and procoagulant capacity of PFVIII resided in the PvWF-enriched fraction, and the same was true for the plasma hypercoagulability following exposure of platelets to PFVIII. These results support the hypothesis that PFVIII-induced platelet activation provides a mechanism for enhancing hemostasis, separate from, and additional to, that due to increased circulating Factor VIII, and it is due to residual PvWF in the PFVIII preparation.

Concurrent measurement of the survival of two populations of rabbit platelets labeled with either two PKH lipophilic dyes or two concentrations of biotin

BACKGROUND

To avoid radioisotopic labeling and permit comparison of the survival of two platelet populations concurrently in one animal, we compared simultaneous recoveries and survival times of homologous rabbit platelets labeled in vitro with the lipophilic dyes PKH26 (red fluorescing) and PKH67 (green fluorescing) and with two levels of biotin (low, 1 microg/ml; high, 10 microg/ml).

METHODS

Blood samples were drawn up to 96 h postinfusion and analyzed by flow cytometry. Biotin-labeled samples were incubated with phycoerythrin-streptavidin before analysis.

RESULTS

Recovery of PKH26-labeled platelets at 1 h was lower (37.5%) than that of PKH67-labeled platelets (47.3%; P < 0.001). Platelet survival times were 62.4 and 61.9 h. Recoveries at 1 h of platelets labeled with two levels of biotin were similar (86.6% and 84.6%) and greater than those of PKH-labeled platelets (P < 0.001). Survival of platelets labeled with biotin did not differ (low, 83.3 h; high, 85.2 h) and was longer than for PKH-labeled platelets (P < 0.01). Labeling methods did not activate platelets (measured by P-selectin expression), nor did they affect platelet responses to adenosine diphosphate (ADP), collagen, or thrombin.

CONCLUSIONS

Labeling with two levels of biotin is superior to labeling with PKH dyes, and is useful for measuring concurrently the survival of two differing platelet populations.

IVIg inhibits reticuloendothelial system function and ameliorates murine passive-immune thrombocytopenia independent of anti-idiotype reactivity

Although the mechanism of action of intravenous immunoglobulin (IVIg) in treating antibody-dependent thrombocytopenia remains unclear, most studies have suggested that IVIg blocks the function of Fc receptors in the reticuloendothelial system (RES) and/or the protective effect may be due to the presence of variable region-reactive (anti-idiotype) antibodies within IVIg. We evaluated the effect of IVIg on platelet counts in a murine model of passively induced immune thrombocytopenia (PIT). Although IVIg was unable to neutralize the binding of two platelet-specific monoclonal antibodies to their target antigens either in vivo or in vitro, it was able to prevent PIT as well as ameliorate pre-established PIT mediated by these antibodies. IVIg adsorbed against the antibody used to induce thrombocytopenia or endogenous murine immunoglobulin also protected against PIT, indicating that antibodies with anti-idiotype activity present in IVIg are not necessary for its effective treatment of PIT. IVIg significantly blocked the ability of the RES to clear antibody-sensitized red blood cells. F(ab')2 fragments of IVIg, which are unable to block the RES but retain the idiotypic regions, were ineffective at protecting mice from PIT. Our data suggest that IVIg exerts its rapid effect by inhibiting RES function and that anti-idiotype interactions are not required.

Quantitative and qualitative assessment of human immunodeficiency virus type 1 (HIV-1)-specific CD4+ T cell immunity to gag in HIV-1-infected individuals with differential disease progression: reciprocal interferon-gamma and interleukin-10 responses

The human immunodeficiency virus type 1 (HIV-1)-specific CD4(+) T cell response was investigated in 33 untreated HIV-1-infected individuals, using highly sensitive ELISPOT assays and intracellular flow cytometry. The median frequencies of interferon (IFN)-gamma-producing HIV-1 gag-specific CD4(+) T cells did not correlate significantly with control of viral replication or progression. HIV-1 gag-specific interleukin (IL)-4-producing cells were rarely detected. Circulating frequencies of CD4(+) T cells constitutively producing IL-10, however, were significantly higher in individuals with progression or active replication. In 17 of 30 HIV-1-infected individuals, gag antigen was observed to induce IL-10 production from CD4(+) T cells. In 2 individuals, early treatment of acute HIV-1 infection "rescued" low to undetectable gag-specific IFN-gamma-producing CD4(+) T cell responses and dramatically down-regulated constitutive IL-10 production from circulating CD4(+) T cells. The detection of HIV-1-specific IL-10-inducing CD4(+) T cells in HIV-1-infected individuals suggests that HIV-1 may directly subvert specific immune responses by IL-10 induction.

Association between cholecystectomy and adenocarcinoma of the esophagus

BACKGROUND & AIMS

Barrett's esophagus, which is linked to adenocarcinoma of the esophagus, is associated with reflux of bile. Duodenogastric reflux is increased after cholecystectomy. This study aims to evaluate if cholecystectomy is associated with an increased risk of adenocarcinoma of the esophagus.

METHODS

A population-based cohort study of cholecystectomized patients in Sweden between 1965 and 1997 cross-linked with the Swedish Cancer Register.

RESULTS

Cholecystectomized patients had an increased risk of adenocarcinoma of the esophagus (standardized incidence ratio [SIR], 1.3; 95% confidence interval [CI], 1.0-1.8). Esophageal squamous-cell carcinoma was not found to be associated with cholecystectomy (SIR, 0.9; 95% CI, 0.7-1.1). Patients with gallstone disease on whom surgery was not performed did not have an increased risk of adenocarcinoma or squamous-cell carcinoma of the esophagus.

CONCLUSIONS

Cholecystectomy is associated with a moderately increased risk of adenocarcinoma of the esophagus, possibly by the toxic effect of refluxed duodenal juice on the esophageal mucosa. Further studies are needed regarding the link between bile reflux and esophageal carcinogenesis.

Phenotypic expression of tissue mosaicism in a 45,X/46,X,dicY(q11.2) female

We describe a girl who presented at the age of 11 years with short stature. She had female external genitalia and some clinical features of Turner syndrome. At laparotomy a uterus and Fallopian tubes and small gonad-like tissue masses in the region of the Fallopian fimbria were found. The tissue masses were removed and histological examination revealed no organized testicular or ovarian morphology. Remnants of Fallopian tubes, epididymis, and clusters of Leydig cells were seen but no Sertoli cells were found. Endocrine studies showed levels of sex hormones consistent with primary gonadal failure. G-banding analysis of 16 blood lymphocytes revealed the karyotype 46,X,dicY(q11.2) in all cells. Varying proportions of X and Y centromeres in blood lymphocytes, skin fibroblasts, and in the incompletely formed Wolffian and Müllerian duct derivatives were demonstrated by FISH. Molecular studies confirmed the absence of most of the long arm of the Y chromosome and an intact short arm. The SRY gene was shown to be present, but we presume that due to the mosaicism the dose was insufficient to allow normal testicular development.

Outcomes of HIV/AIDS case management in New York

The purpose of this study was to examine HIV case management (CM) outcomes in New York State. The results presented here are part of a larger study that explored: client needs identified during CM, success in arranging needs, other case managers used by the client, coordination between multiple case managers, client satisfaction with CM, and the correlation between health care costs and CM. This paper focuses on the linkage of clients with services. Twenty-eight agencies and 588 clients participated in the study. Each client's chart was reviewed; clients and case managers were interviewed. Almost 9,000 client needs were identified; 79.3% of these needs were for services. Over 72% of needed services were arranged for clients. However, of the services arranged, 12.9% were never utilized. Success in arranging services did not vary based on client demographics; client utilization of services, once arranged, varied based on only one demographic factor (clients who lived outside of New York City had higher utilization rates than those who lived in the city, p < or = 0.05). Services provided directly by the CM agency were arranged and utilized more frequently than services provided by another agency (p < or = 0.05). Medical needs were arranged and utilized at a higher rate-and legal needs at a lower rate-than other services, regardless of where the service was provided (p < or = 0.05). On average it took 2.3 months to arrange a service; however it took less time to arrange medical services and more time to arrange legal services (p < or = 0.05). Females, individuals whose mode of HIV transmission was heterosexual contact, clients whose children were living with them, the inadequately housed, and those without a high school diploma had significantly more needs than other clients (p < or = 0.05). Our study supports CM models that provide intensive services to women with children; the provision of multiple services, in addition to CM, within a single agency; and the need for case manager training on how to work with clients to increase service utilization.