Suspension and resumption of kidney transplant programmes during the COVID-19 pandemic: perspectives from patients, caregivers and potential living donors - a qualitative study

Many countries have suspended kidney transplantation programmes during the COVID‐19 pandemic because of concerns for patient safety and the shortage of healthcare resources. This study aimed to describe patient, family member and potential donor perspectives on the suspension and resumption of kidney transplant programmes due to COVID‐19. We conducted seven online focus groups involving 31 adult kidney transplant candidates (n = 22), caregivers (n = 4) and potential donors (n = 5). Transcripts were analysed thematically. We identified five themes: cascading disappointments and devastation (with subthemes of shattering hope, succumbing to defeat, regret and guilt); helplessness and vulnerability (fear of declining health, confronted by the threat of and change in dialysis, disconnected from health care, susceptibility to infective complications); stress from uncertainty (confusion from conflicting information, unable to forward plan), exacerbating burdens (incurring extra financial costs, intensifying caregiver responsibilities), and sustaining health through the delay (protecting eligibility, relying on social support, adapting to emerging modalities of care). During the suspension of kidney transplantation programmes, patients felt medically vulnerable because of declining health, susceptibility to infection and reduced access to care. There is a need to address health vulnerabilities, disappointment, uncertainty and additional burdens arising from the suspension of kidney transplantation programmes.

Correlation between computed tomography volumetry and nuclear medicine split renal function in live kidney donation: a single-centre experience

BACKGROUND

Potential live renal donors undergo both renal computed tomography angiogram (CTA) and nuclear imaging dimercaptosuccinic acid (DMSA) scans. Each kidney's renal function and vascular anatomy influences the choice of donor side. Although DMSA measures differential blood flow, it is a surrogate for renal function and nephron mass. Computed tomography techniques can provide volumetry information. The aim of this study was to determine the relationship between measured split renal volumes on computed tomography versus renal volumes derived from DMSA split function in live donors.

METHODS

Prospective data of live kidney donors assessed at a single Australian centre from 2014 to 2017 were reviewed. All patients had pre-operative CTA and DMSA imaging. Renal volume was determined via semi-automated software calculation from CTA three-dimensional image reconstructions by one investigator. Measured split renal volume was compared against calculated renal volume using measured DMSA split function (percentage split function multiplied by total renal volume).

RESULTS

Fifty-three patients were included in the study. Split renal volumes on three-dimensional CTA images correlate to calculated split volumes determined from DMSA (Pearson coefficient 0.95 for right renal volume, 0.95 for left). The decision of which kidney to remove can be achieved with CTA only. Omitting a DMSA scan would reduce the radiation load by 0.70 mSv (35 chest X-rays) and potential cost saving of AU$1062.00 per donor.

CONCLUSION

CTA technology allows accurate assessment of renal volumes that correlate well with DMSA split function. Avoiding a DMSA scan results in cost and radiation reduction in the assessment of a live kidney donor.

Infectious Disease Transmission in Solid Organ Transplantation: Donor Evaluation, Recipient Risk, and Outcomes of Transmission

In 2016, the Transplantation Society of Australia and New Zealand, with the support of the Australian Government Organ and Tissue authority, commissioned a literature review on the topic of infectious disease transmission from deceased donors to recipients of solid organ transplants. The purpose of this review was to synthesize evidence on transmission risks, diagnostic test characteristics, and recipient management to inform best-practice clinical guidelines. The final review, presented as a special supplement in Transplantation Direct, collates case reports of transmission events and other peer-reviewed literature, and summarizes current (as of June 2017) international guidelines on donor screening and recipient management. Of particular interest at the time of writing was how to maximize utilization of donors at increased risk for transmission of human immunodeficiency virus, hepatitis C virus, and hepatitis B virus, given the recent developments, including the availability of direct-acting antivirals for hepatitis C virus and improvements in donor screening technologies. The review also covers emerging risks associated with recent epidemics (eg, Zika virus) and the risk of transmission of nonendemic pathogens related to donor travel history or country of origin. Lastly, the implications for recipient consent of expanded utilization of donors at increased risk of blood-borne viral disease transmission are considered.

Age-Related Differences in Socio-demographic and Behavioral Determinants of HIV Testing and Counseling in HPTN 043/NIMH Project Accept

Youth represent a large proportion of new HIV infections worldwide, yet their utilization of HIV testing and counseling (HTC) remains low. Using the post-intervention, cross-sectional, population-based household survey done in 2011 as part of HPTN 043/NIMH Project Accept, a cluster-randomized trial of community mobilization and mobile HTC in South Africa (Soweto and KwaZulu Natal), Zimbabwe, Tanzania and Thailand, we evaluated age-related differences among socio-demographic and behavioral determinants of HTC in study participants by study arm, site, and gender. A multivariate logistic regression model was developed using complete individual data from 13,755 participants with recent HIV testing (prior 12 months) as the outcome. Youth (18-24 years) was not predictive of recent HTC, except for high-risk youth with multiple concurrent partners, who were less likely (aOR 0.75; 95% CI 0.61-0.92) to have recently been tested than youth reporting a single partner. Importantly, the intervention was successful in reaching men with site specific success ranging from aOR 1.27 (95% CI 1.05-1.53) in South Africa to aOR 2.30 in Thailand (95% CI 1.85-2.84). Finally, across a diverse range of settings, higher education (aOR 1.67; 95% CI 1.42, 1.96), higher socio-economic status (aOR 1.21; 95% CI 1.08-1.36), and marriage (aOR 1.55; 95% CI 1.37-1.75) were all predictive of recent HTC, which did not significantly vary across study arm, site, gender or age category (18-24 vs. 25-32 years).

Four-dimensional Fano toric complete intersections

We find at least 527 new four-dimensional Fano manifolds, each of which is a complete intersection in a smooth toric Fano manifold.

Cattle methane emission and pasture carbon dioxide balance of a grazed grassland

Grasslands constitute a major land use globally and are a potential sink of atmospheric carbon dioxide (CO). They are also an important habitat for wildlife and a source of feed that supports ruminant livestock production. However, the presence of ruminants grazing these grasslands is also a source of methane (CH) that contributes to buildup of greenhouse gases in the atmosphere. Our study measured enteric CH from 40 confined heifers in 1-ha paddocks using a dispersion model and CO exchange from an adjacent grassland site using a micrometeorological technique. The study was conducted at a mixed prairie grassland located in southern Alberta, Canada. The mean (standard error) CH emission was 189 (± 6) g animal d over four campaigns (over a 3-yr period). The daily averaged CO exchange from the grassland peaked at +2.2 g m h (sink) in early July and declined to negative values (source) in mid-August. Annually, the grazed grassland was either a net sink for carbon (C) at +40 kg C ha or a small source at -7 kg C ha depending on a cattle stocking density of 0.1 or 0.2 animals ha, respectively. However, in basing the exchange on CO equivalence (CO), both stocking densities resulted in the grazed grassland being a source of greenhouse gas of -9 or -338 kg CO ha y. This study illustrates the need to consider the cattle CH emissions and the stocking density when evaluating the environmental sustainability of grazed grasslands.

Disseminated microsporidiosis with Encephalitozoon species in a renal transplant recipient

To our knowledge, 5 cases of disseminated microsporidiosis with Encephalitozoon species have been reported worldwide in transplant recipients. George et al. present the first such case in Australia, to be reported and treated with good clinical recovery.

Technical note: Can the sulfur hexafluoride tracer gas technique be used to accurately measure enteric methane production from ruminally cannulated cattle?

An experiment was conducted to determine whether using ruminally cannulated cattle affects the estimate of enteric methane (CH(4)) emissions when using the sulfur hexafluoride (SF(6)) tracer technique with samples taken from a head canister. Eleven beef cattle were surgically fitted with several types of ruminal cannula (2C, 3C, 3C+washer, 9C; Bar Diamond, Parma, ID). The 2C and 3C models (outer and inner flanges with opposite curvature) had medium to high leakage, whereas the 9C models (outer and inner flanges with the same curvature) provided minimum to moderate leakage of gas. A total of 48 cow-day measurements were conducted. For each animal, a permeation tube containing sulfur hexafluoride (SF(6)) was placed in the rumen, and a sample of air from around the nose and mouth was drawn through tubing into an evacuated canister (head canister). A second sample of air was collected from outside the rumen near the cannula into another canister (cannula canister). Background concentrations were also monitored. The methane (CH(4)) emission was estimated from the daily CH(4) and SF(6) concentrations in the head canister (uncorrected). The permeation SF(6) release rate was then partitioned based on the proportion of the SF(6) concentration measured in the head vs. the cannula canister. The CH(4) emissions at each site were calculated using the two release rates and the two CH(4):SF(6) concentration ratios. The head and cannula emissions were summed to obtain the total emission (corrected). The difference (corrected - uncorrected) in CH4 emission was attributed to the differences in CH(4):SF(6) ratio at the 2 exit locations. The proportions of CH(4) and SF(6) recovered at the head were greater (P < 0.001) for the 9C cannulas (64% and 66%) compared with the other cannulas, which were similar (P > 0.05; 2C, 6% and 4%; 3C, 17% and 15%; 3C+washer, 19% and 14%). Uncorrected CH(4) emissions were ± 10% of corrected emissions for 53% of the cow-day measurements. Only when more than 80% of the SF(6) escaped via the rumen did the difference between the uncorrected and corrected CH(4) emissions exceed 20%. We concluded that using cannulated cattle introduces more variability into the SF(6) technique used with a head canister, a technique that is already highly variable. Thus, use of cannulated animals is not recommended when using the SF(6) technique with head canister. However, if cannulated cattle are used, the cannulas need to be tight-fitting to minimize leakage, and large animal numbers are needed to overcome the additional variability.

Performance of a dispersion model to estimate methane loss from cattle in pens

Accurate measurements of enteric methane (CH(4)) emissions from cattle (Bos taurus) are necessary to improve emission coefficients used in national emissions inventories, and to evaluate mitigation strategies. Our study was conducted to evaluate a novel approach that allowed near continuous CH(4) measurement from beef cattle confined in pens. The backward Lagrangian Stochastic (bLS) dispersion technique was used in conjunction with global position system (GPS) information from individual animals, to evaluate CH(4) emissions from pens of cattle. The dispersion technique was compared to estimates of CH(4) production using the SF(6) tracer technique. Sixty growing beef cattle were fed a diet containing 60% barley silage (dry matter basis) supplemented with either barley (Hordeum vulgare L.) grain or corn (Zea mays L.) distillers dried grains. The results show that daily CH(4) emissions were about 7% lower for the dispersion technique than for the tracer technique (185 vs. 199 g CH(4) animal(-1) d(-1)). The precision of the dispersion technique, relative to the SF(6) tracer technique, expressed by the Pearson coefficient was 0.76; the relative accuracy given by the concordance coefficient was 0.69. The bLS dispersion technique was able to detect differences (P < 0.05) due to diet and has the added advantage of measuring the pattern of CH(4) production during the 24-h period, with emissions ranging from 161 to 279 g CH(4) animal(-1) d(-1). Configuring the cattle as point sources resulted in more accurate CH(4) emissions than assuming a uniform area release from the pen surface. The results indicate that the bLS dispersion technique using cattle as point sources can be used to accurately measure enteric CH(4) from cattle and to evaluate the impact of dietary mitigation strategies.

Nasal decolonization of Staphylococcus aureus with mupirocin: strengths, weaknesses and future prospects

Staphylococcus aureus in the nose is a risk factor for endogenous staphylococcal infection. UK guidelines recommend the use of mupirocin for nasal decolonization in certain groups of patients colonized with methicillin-resistant S. aureus (MRSA). Mupirocin is effective at removing S. aureus from the nose over a few weeks, but relapses are common within several months. There are only a few prospective randomized clinical trials that have been completed with sufficient patients, but those that have been reported suggest that clearance of S. aureus from the nose is beneficial in some patient groups for the reduction in the incidence of nosocomial infections. There is no convincing evidence that mupirocin treatment reduces the incidence of surgical site infection. New antibiotics are needed to decolonize the nose because bacterial resistance to mupirocin is rising, and so it will become less effective. Furthermore, a more bactericidal antibiotic than mupirocin is needed, on the grounds that it might reduce the relapse rate, and so clear the patient of MRSA for a longer period of time than mupirocin.

Quantifying ammonia emissions from a cattle feedlot using a dispersion model

Livestock manure is a significant source of ammonia (NH3) emissions. In the atmosphere, NH3 is a precursor to the formation of fine aerosols that contribute to poor air quality associated with human health. Other environmental issues result when NH3 is deposited to land and water. Our study documented the quantity of NH3 emitted from a feedlot housing growing beef cattle. The study was conducted between June and October 2006 at a feedlot with a one-time capacity of 22,500 cattle located in southern Alberta, Canada. A backward Lagrangian stochastic (bLS) inverse-dispersion technique was used to calculate NH3 emissions, based on measurements of NH3 concentration (open-path laser) and wind (sonic anemometer) taken above the interior of the feedlot. There was an average of 3146 kg NH3 d(-1) lost from the entire feedlot, equivalent to 84 microg NH3 m(-2) s(-1) or 140 g NH3 head(-1) d(-1). The NH3 emissions correlated with sensible heat flux (r2 = 0.84) and to a lesser extent the wind speed (r2 = 0.56). There was also evidence that rain suppressed the NH3 emission. Quantifying NH3 emission and dispersion from farms is essential to show the impact of farm management on reducing NH3-related environmental issues.

Methane emissions from beef cattle: Effects of monensin, sunflower oil, enzymes, yeast, and fumaric acid

Methane emitted from the livestock sector contributes to greenhouse gas (GHG) emissions. Understanding the effects of diet on enteric methane production can help refine GHG emission inventories and identify viable GHG reduction strategies. Our study focused on measuring methane and carbon dioxide emissions, total-tract digestibility, and ruminal fermentation in growing beef cattle fed a diet supplemented with various additives or ingredients. Two experiments, each designed as a 4 x 4 Latin square with 21-d periods, were conducted using 16 Holstein steers (initial BW 311.6 +/- 12.3 kg). In Exp. 1, treatments were control (no additive), monensin (Rumensin, Elanco Animal Health, Indianapolis, IN; 33 mg/kg DM), sunflower oil (400 g/d, approximately 5% of DMI), and proteolytic enzyme (Protex 6-L, Genencor Int., Inc., CA; 1 mL/kg DM). In Exp. 2, treatments were control (no additive), Procreatin-7 yeast (Prince Agri Products, Inc., Quincy, IL; 4 g/d), Levucell SC yeast (Lallemand, Inc., Rexdale, Ontario, Canada; 1 g/d), and fumaric acid (Bartek Ingredients Inc., Stoney Creek, Ontario, Canada; 80 g/d). The basal diet consisted of 75% barley silage, 19% steam-rolled barley grain, and 6% supplement (DM basis). Four large chambers (two animals per chamber) were equipped with lasers and infrared gas analyzers to measure methane and carbon dioxide, respectively, for 3 d each period. Total-tract digestibility was determined using chromic oxide. Approximately 6.5% of the GE consumed was lost in the form of methane emissions from animals fed the control diet. In Exp. 1, sunflower oil decreased methane emissions by 22% (P = 0.001) compared with the control, whereas monensin (P = 0.44) and enzyme had no effect (P = 0.82). However, oil decreased (P = 0.03) the total-tract digestibility of NDF by 20%. When CH(4) emissions were corrected for differences in energy intake, the loss of GE to methane was decreased by 21% (P = 0.002) using oil and by 9% (P = 0.09) using monensin. In Exp. 2, Procreatin-7 yeast (P = 0.72), Levucell SC yeast (P = 0.28), and fumaric acid (P = 0.21) had no effect on methane emissions, although emissions as a percentage of GE intake were 3% (non-significant, P = 0.39) less for steers fed Procreatin-7 yeast compared with the control. This study demonstrates that sunflower oil, ionophores, and possibly some yeast products can be used to decrease the GE lost as methane from cattle, but fiber digestibility is impaired with oil supplementation.

Effects of a behavioural intervention to reduce acquisition of HIV infection among men who have sex with men: the EXPLORE randomised controlled study

BACKGROUND

Effective interventions are needed to prevent acquisition of HIV infection in men who have sex with men. To date, no behavioural interventions specifically for this risk group have been tested with HIV infection as the primary outcome.

METHODS

This multisite two-group randomised controlled phase IIb trial tested the efficacy of a behavioural intervention in preventing HIV infection among 4295 men who have sex with men. The experimental intervention consisted of ten one-on-one counselling sessions followed by maintenance sessions every 3 months. The standard condition was twice-yearly Project RESPECT individual counselling. Twice-yearly follow-up visits included testing for HIV antibody and assessment of behavioural outcomes.

FINDINGS

The rate of acquisition of HIV infection was 18.2% (95% CI -4.7 to 36.0) lower in the intervention group than the standard group. Adjustment for baseline covariates attenuated the intervention effect to 15.7% (-8.4 to 34.4). The effect was more favourable in the first 12-18 months of follow-up. The occurrence of unprotected receptive anal intercourse with HIV-positive and unknown-status partners was 20.5% (10.9 to 29.0) lower in the intervention than in the standard group.

INTERPRETATION

The results from the primary analyses allow us to rule out that the experimental intervention is associated with a 35% lower rate of HIV acquisition than in the standard group. The overall estimate of a difference of 18.2%, more favourable estimates of effect in the first 12-18 months, and similar effects on risk behaviours suggest that prevention of HIV infection among men who have sex with men by a behavioural intervention is feasible. Further work should be done to develop more effective interventions.

Atmospheric ammonia, volatile fatty acids, and other odorants near beef feedlots

Intensive livestock operations can release odorous gases from stored or land-applied manure. We measured concentrations of dust and 14 odor-causing gases at increasing distances from four feedlots near Lethbridge, southern Alberta, Canada. Concentration was determined from the amount of total dust or gas accumulated in the sampIers, and the volume of air sampled. Adjacent the feedlots, the maximum concentration of many volatile fatty acids exceeded reported odor detection thresholds; the maximum ammonia concentration was close to the threshold. Ammonia and butyric acid approached or exceeded their individual odor thresholds as far as 200 m downwind of the feedlots. Highest concentrations were measured adjacent to land where manure was being applied. None of the odorant concentrations exceeded their irritation threshold. There was a positive relationship between ammonia concentration and odor intensity as well as dry deposition. Much of the emitted ammonia was deposited to soil immediately downwind, enough to supply all the nitrogen needed for crop growth. Odorant concentrations declined sharply with distance, though measurable odor occasionally persisted to 1 km from the feedlot, beyond the minimum separation guidelines (Alberta) for a single residential dwelling. The weekly averaged total suspended particulates (> 5 microm) were below the Alberta guideline criterion except for one period. Differences among feedlots in odorant plume concentrations were partly related to the stocking density of feedlots, which presumably affects manure moisture and amount of volatiles within the pens.

A review of research on the structure, process and outcome of liaison mental health services

Liaison mental health services (LMHS) developed originally to address the mental health needs of people with physical illnesses in general hospitals and more recently to work also with people with mental health problems presenting at non-mental health services. The purpose of the present paper was to review empirical research on the structure, process and outcome of liaison mental health services using systematic review methods. Following a comprehensive search strategy, the authors reviewed 48 papers published between 1975 and 2001. There is an extensive international literature on LMHS, much of which describes the structure and process of liaison work. Studies evaluating the outcomes of liaison mental health services are fewer, and handicapped by methodological flaws, some of which are serious enough to cast doubts on the reported results. Professionals and clients value LMHS. LMHS based in accident and emergency (A & E) departments appear to ease the burden of general A & E staff, help clients access mental health services and reduce re-admission rates of people with mental health problems. There is little evidence supporting one model of configuring LMHS over another.

Effect of diet on odorant emissions from cattle manure

Ammonia loss from livestock manure is of special concern because it contributes to odour, can impact non-targeted environments through atmospheric deposition, and represents a potential loss of available nitrogen in manure used as fertilizer for crop growth. Our study investigated the effect of three barley-based diets on manure composition and the emissions of ammonia and volatile fatty acids (VFA) from beef feedlot manure. The results of our study suggest that the metabolizable protein requirements of heavyweight feedlot cattle (400 to 550 kg) were met when finished on a barley grain and barley silage diet [12.9% crude protein (CP)]. Therefore, the ability to reduce total N content of manure or manipulate the route of N excretion is limited, unless lower protein ingredients, such as corn silage or cereal straw, were incorporated into the diet to lower the basal diet CP concentration. There was no relationship between protein level and animal weight gain in our study. There was a positive relationship (P < 0.05) between level of intake protein and ammonium-N content of the surface-sampled pen manure. However, chamber data suggested that the higher ammonium-N content of manure did not translate to any significant difference in ammonia emissions, although the lowest emission rate for surface manure coincided with the lowest protein level. There was also no significant difference in VFA emission related to diet treatments. Key words: Ammonia, volatile fatty acid, odour intensity, cattle, manure, diet

Segmental infarction with graft dysfunction: an emerging syndrome in renal transplantation?

BACKGROUND

Segmental allograft infarction is a poorly characterized complication following renal transplantation. The present study was undertaken with the goal of defining the incidence, clinical characteristics, pathogenesis, and prognosis of this entity.

METHODS

A retrospective study was performed, reviewing the renal scans performed on all renal transplant recipients at our institution, from January 1997 to January 2000. Segmental infarction was diagnosed on the basis of a significant elevation in lactate dehydrogenase (>500 U/l) together with a photopenic perfusion defect. In these patients, graft characteristics, operative details, clinical course, and long-term outcomes were evaluated.

RESULTS

Segmental infarction was identified in 13 of 277 consecutive renal transplant recipients (4.7%). In nine recipients the onset of infarction occurred within 24 h after transplantation. All received marginal grafts, and in five recipients the transplant operation was complicated by major blood loss. Eight of these recipients exhibited primary non-function, or developed dialysis-dependent renal failure after the onset of infarction. In four patients, the onset of infarction occurred after 24 h (35 h to 10 days). One recipient demonstrated primary non-function, and renal function deteriorated after the onset of infarction in the remaining three. Overall, long-term graft function was impaired. Two allografts never functioned, and six recipients had nadir creatinine clearances below 60 ml/min.

CONCLUSIONS

The pathogenesis of segmental infarction appears to be multi-factorial, reflecting the combination of an initiating anatomic lesion and potentiating thrombogenic milieu. Segmental infarction typically occurs in the early postoperative period, and prompt diagnosis is difficult to obtain. In view of this, prophylactic heparin may be warranted for those at highest risk. There was no correlation between the infarct area and the graft function, and the long-term graft function is compromised out of proportion to the extent of parenchymal loss. This finding highlights the role of predisposing factors, particularly marginal graft quality, in determining the functional outcome. Segmental infarction may be more frequently encountered as cadaveric organ shortages encourage greater use of marginal donor kidneys.

National trends in condom use among at-risk heterosexuals in the united states

Based on national level surveys, we examined data relevant to the United States' overall effort to prevent the spread of HIV among heterosexual adults. We examined changes in condom use among at-risk heterosexuals over the past decade. The observed increases over time in condom use across all heterosexual at-risk population segments are consistent with the observed (declines) trends in HIV and syphilis in the 1990s. These results and findings from prior studies suggest that U.S. efforts to facilitate condom use and contain HIV and related sexually transmitted disease (STD)-cofactors among adult at risk heterosexuals was succeeding over most of the 1990s. The absence of national level behavioral trend data after 1996, and the ambiguities of HIV spread suggest some caution in projecting trends into this century. National and local efforts need to be directed at sustaining behavioral change and conducting more rigorous studies on population trends in HIV/STD-related behaviors/pathogens.

Positive and negative life events after counselling and testing: the Voluntary HIV-1 Counselling and Testing Efficacy Study

INTRODUCTION

The results of the Voluntary HIV-1 Counselling and Testing Efficacy Study support the efficacy and cost-effectiveness of HIV voluntary counselling and testing (VCT) for reducing risk behaviors in three developing countries.

METHODS

This report explores the social consequences of HIV VCT by examining the incidence of positive and negative life events at the first follow-up (an average of 7.3 months after recruitment). The incidence of positive and negative life events was compared between: (i) those who were randomly assigned to HIV VCT versus health information (HI); (ii) those who tested seronegative and those who tested seropositive; and (iii) those who disclosed their serostatus and those who did not.

RESULTS

The occurrence of most negative life events was rare (0--4%); positive life events were more common (17--39%). With few exceptions, those assigned to HIV VCT were no more likely to experience negative life events than those who were assigned to HI. For individuals, positive serostatus was associated with increased support from health professionals, the break-up of a marriage and being neglected or disowned by their family. Serodiscordant couples with an HIV-positive woman were most likely to report the break-up of a marriage (20 versus 0--7% for other groups) and the break-up of a sexual relationship (45 versus 22--38% for other groups). Disclosure was associated with strengthening of a sexual relationship except for HIV-seropositive women.

CONCLUSION

These findings, in combination with findings supporting the efficacy and cost-effectiveness of HIV VCT, support the dissemination of HIV VCT with appropriate support services in developing countries.

Hepatitis B vaccines: assessment of the seroprotective efficacy of two recombinant DNA vaccines

BACKGROUND

In universal vaccination programs, when there is no postvaccination sero-1 logic assessment of response, there must be confidence that the vaccines used provide a high degree of seroprotection.

OBJECTIVE

This parallel analysis of 2 recombinant hepatitis B vaccines (Engerix B and Recombivax/HB-Vax II) was conducted to review the seroprotective efficacy of each vaccine in defined populations.

METHODS

Clinical studies of the 2 vaccines published as manuscripts or conference abstracts in the public domain between January 1986 and April 1999 were identified retrospectively by unrestricted screening of journals through BIOSIS, MEDLINE, and EMBASE and the Internet. Unpublished or internal company data were excluded to maintain impartiality. The studies were reviewed and analyzed. The studies were not assessed for quality other than a judgment of their eligibility for inclusion in the analysis. The primary outcome measure was the proportion of subjects in defined populations who showed an early seroprotective response to currently licensed vaccination schedules. Summary statistical analyses of seroprotective response rates and 95% CIs were calculated for each vaccine for each population. Seroprotective response was defined by an anti-hepatitis B surface antigen titer > or =10 IU/L measured between 1 and 3 months after the final vaccination. Because the study was designed specifically to review published immunogenicity data, safety data were not assessed. The study was not designed to demonstrate superiority of one vaccine over the other.

RESULTS

A total of 181 clinical studies representing 32,904 vaccinated subjects were reviewed and analyzed, of whom 24,277 had been vaccinated with Engerix B and 8627 vaccinated with Recombivax/ HB-Vax II. Seroprotection was achieved in 20,060 subjects (95.8%) with Engerix B and in 7774 subjects (94.3%) with Recombivax/HB-Vax II in the normal population vaccinated according to currently licensed 3-dose schedules. In a subgroup analysis, response rates in health care workers were 6492 subjects (94.5%) for Engerix B and 3245 subjects (92.2%) for Recombivax/HB-Vax II. Children and adolescents (1-19 years) showed the highest response rates to vaccination (4612 [98.6%], Engerix B; 2292 [98.9%], Recombivax/HB-Vax II). A total of 2875 infants (<1 year) (95.8%) achieved seroprotection with Engerix B; 701 (88.5%) achieved seroprotection with Recombivax/ HB-Vax II.

CONCLUSIONS

Hepatitis B vaccination programs using either Engerix B or Recombivax/HB-Vax II can achieve high seroprotective response rates, particularly in childhood and adolescence. Ideally, younger populations should be a primary target in current universal vaccination programs.

Voluntary counseling, testing, and referral for HIV: new technologies, research findings create dynamic opportunities

Programs for voluntary counseling and testing (VCT) for HIV play an increasingly important role in comprehensive prevention and care strategies. New technological advancements and behavioral interventions can improve the effectiveness of VCT as a tool for preventing new HIV infections and helping HIV-positive individuals access appropriate care. With growing consensus that early access to HIV therapy increases its effectiveness, and that individuals diagnosed with HIV reduce risk behavior, VCT has become integral to the continuum of HIV primary care. However, federal funding of VCT has declined, with concomitant decreases in numbers of people being tested. An estimated 200,000 people in the United States remain unaware that they are HIV positive, and many at-risk individuals do not seek out standard HIV counseling and testing services. To increase the acceptability and effectiveness of VCT, the authors recommend that VCT programs employ outreach programs offering anonymous testing to reach those at heightened risk of HIV infection, and to make rapid use of new technologies and counseling strategies to improve the reach and efficacy. Given the important role that VCT can play in both prevention and early treatment, the authors recommend significant increases in federal support.

Cost-effectiveness of voluntary HIV-1 counselling and testing in reducing sexual transmission of HIV-1 in Kenya and Tanzania

BACKGROUND

Access to HIV-1 voluntary counselling and testing (VCT) is severely limited in less-developed countries. We undertook a multisite trial of HIV-1 VCT to assess its impact, cost, and cost-effectiveness in less-developed country settings.

METHODS

The cost-effectiveness of HIV-1 VCT was estimated for a hypothetical cohort of 10000 people seeking VCT in urban east Africa. Outcomes were modelled based on results from a randomised controlled trial of HIV-1 VCT in Tanzania and Kenya. Our main outcome measures included programme cost, number of HIV-1 infections averted, cost per HIV-1 infection averted, and cost per disability-adjusted life-year (DALY) saved. We also modelled the impact of targeting VCT by HIV-1 prevalence of the client population, and the proportion of clients who receive VCT as a couple compared with as individuals. Sensitivity analysis was done on all model parameters.

FINDINGS

HIV-1 VCT was estimated to avert 1104 HIV-1 infections in Kenya and 895 in Tanzania during the subsequent year. The cost per HIV-1 infection averted was US$249 and $346, respectively, and the cost per DALY saved was $12.77 and $17.78. The intervention was most cost-effective for HIV-1-infected people and those who received VCT as a couple. The cost-effectiveness of VCT was robust, with a range for the average cost per DALY saved of $5.16-27.36 in Kenya, and $6.58-45.03 in Tanzania. Analysis of targeting showed that increasing the proportion of couples to 70% reduces the cost per DALY saved to $10.71 in Kenya and $13.39 in Tanzania, and that targeting a population with HIV-1 prevalence of 45% decreased the cost per DALY saved to $8.36 in Kenya and $11.74 in Tanzania.

INTERPRETATION

HIV-1 VCT is highly cost-effective in urban east African settings, but slightly less so than interventions such as improvement of sexually transmitted disease services and universal provision of nevirapine to pregnant women in high-prevalence settings. With the targeting of VCT to populations with high HIV-1 prevalence and couples the cost-effectiveness of VCT is improved significantly.

Cerebral white matter lesions in primary Sjögren's syndrome: a controlled study

OBJECTIVE

To determine the prevalence of neurological and magnetic resonance imaging (MRI) abnormalities in a well defined population of unselected patients with primary Sjögren's syndrome (SS) and age and sex matched healthy patients.

METHODS

Thirty patients with SS and 29 age and sex matched controls were examined by a neurologist and subsequently underwent MRI scanning with a 1.0 Tesla Siemens Impact MR scanner. Scans were graded by a neuroradiologist blinded to the clinical status of each subject. The number and location of white matter lesions > 3 mm in long axis (to exclude non-specific perivascular changes) were recorded for each subject.

RESULTS

There was a significant increase in lesions detected by MRI in SS patients versus controls (p = 0.02) including deep white matter lesions (p = 0.03) and subcortical white matter lesions (p = 0.02). The presence of white matter lesions did not correlate with serum IgG or rheumatoid factor levels, or with presence of anticardiolipin antibodies. No subjects had symptoms or signs of serious neurological disease including multiple sclerosis, and corpus callosal lesions commonly seen in multiple sclerosis were notably absent in this study.

CONCLUSION

Cerebral white matter lesions detected by MRI are more frequent in patients with primary SS than control subjects, yet do not appear to be associated with significant clinical manifestations. Although the pathological nature of these lesions is yet to be defined, their presence should not be over-interpreted.

Cutaneous necrosis from calcific uremic arteriolopathy

Calcific uremic arteriolopathy (calciphylaxis) is an uncommon complication of chronic renal failure that is associated with high morbidity and mortality. We report 16 patients (13 female) who presented between 1985 and 1996. All patients developed painful livido reticularis that progressed to cutaneous necrosis and ulceration (11 cases on the proximal extremities and five cases on the distal extremities). Two patients with predominately distal leg disease survived; the cause of death in the other 14 patients was sepsis (six patients), withdrawal from dialysis (three), cardiac arrest (three), and gastrointestinal hemorrhage (two). Mesenteric ischemia from intestinal vascular calcification occurred in two cases. Clinical factors identified included the use of warfarin therapy in seven cases and significant weight loss (>10% body weight) in seven cases in the 6 months preceding the development of calcific uremic arteriolopathy. Skin pathology was studied in 12 cases, with all showing calcific panniculitis and small vessel calcification. Electron microscopic spectral analysis of the mineral content of the calcific lesions in the subcutaneous tissue showed only calcium and phosphorous. In two cases, substitution of low molecular weight heparin for warfarin therapy resulted in clinical improvement. Current theories of pathogenesis and treatment are reviewed. This study confirms the high morbidity and mortality of calcific uremic arteriolopathy producing ischemic tissue necrosis while drawing attention to significant weight loss and warfarin therapy as risk factors for the development of ischemic tissue necrosis. Hyperbaric oxygen therapy warrants further study.

HLA class II phenotype controls diversification of the autoantibody response in primary Sjögren's syndrome (pSS)

The coexistence of anti-La (SS-B) and anti-Ro (SS-A) autoantibodies in pSS is probably explained by intermolecular spreading of autoimmunity toward different components of the La/Ro ribonucleoprotein (RNP). In order to evaluate the role of the HLA class II phenotype in controlling diversification of this autoantibody response, 80 patients with pSS were typed by polymerase chain reaction sequence-specific oligonucleotide (PCR-SSO) at the HLA class II loci DRB1, DQA1 and DQB1. Serum samples were examined for anti-La and anti-Ro by counterimmunoelectrophoresis and by ELISA using purified recombinant La and 60-kD Ro proteins. Patient sera were classified according to the extent of diversification of the anti-La, anti-Ro response including the presence or absence of precipitating anti-La antibodies. Immunogenic characteristics of these stratified groups were then studied. All patients with pSS, with or without autoantibodies to Ro and La, were found to have at least one of the HLA-DRB1 types DR2, DR3 or DR5. The HLA DR3-DQA1*0501-DQB1*02 (DR3-DQ2) haplotype was primarily associated with a diversified La/Ro RNP response containing precipitating autoantibodies to La (P<0.001); whereas the haplotype HLA DR2-DQA1*0102-DQB1*0602 (DR2-DQ1) was associated with a less diversified La/Ro RNP response containing non-precipitating (restricted epitope) anti-La autoantibodies (P<0.001). Anti-La-positive patients lacking both HLA-DR2 and HLA-DR3 all expressed the HLA-DQA1*0501 allele, which was present at increasing frequency with greater diversification of the anti-La/Ro autoantibody response. The association of distinct HLA haplotypes with different degrees of autoantibody diversification in patients with pSS suggests a model of HLA-restricted presentation of La/Ro peptide determinants to autoreactive helper T cells. We propose that non-precipitating anti-La responses are driven by limited intermolecular help from DR2-DQ1-restricted T helper cells recognizing Ro determinants. On the other hand, we speculate that the more diversified, precipitating anti-La responses obtain more efficient cognate T help from DR3-DQ2-restricted T helper cells recognizing La determinants, where HLA-DQA1*0501 may be a critical determinant for antigen presentation.