Pre-existing diabetes is a risk factor for increased rates of cellular rejection after kidney transplantation: an observational cohort study

AIM

To investigate whether people with diabetes have an elevated risk of kidney allograft rejection in a well characterized clinical cohort in the setting of contemporary immunosuppression.

METHODS

We conducted a retrospective cohort study including all kidney allograft recipients at a single centre between 2007 and 2015, linking clinical, biochemical and histopathological data from electronic patient records.

RESULTS

Data were analysed for 1140 kidney transplant recipients. The median follow-up was 4.4 years post-transplantation, and 117 of the kidney transplant recipients (10.2%) had diabetes at time of transplantation. Kidney allograft recipients with vs without diabetes were older (53 vs 45 years; P<0.001) and more likely to be non-white (41.0% vs 26.4%; P=0.001). Kidney allograft recipients with vs without diabetes had a higher risk of cellular rejection (19.7% vs 12.4%; P=0.024), but not of antibody-mediated rejection (3.4% vs 3.7%; P=0.564). Graft function and risk of death-censored graft loss were similar in the two groups, but kidney allograft recipients with diabetes had a higher risk of death and overall graft loss than those without diabetes. In a Cox regression model of non-modifiable risk factors at time of transplantation, diabetes was found to be an independent risk factor for cellular rejection (hazard ratio 1.445, 95% CI 1.023-1.945; P=0.042).

CONCLUSIONS

Kidney allograft recipients with diabetes at transplantation should be counselled regarding their increased risk of cellular rejection but reassured regarding the lack of any adverse impact on short-to-medium term allograft function or survival.

Qualitative release assessment to estimate the likelihood of henipavirus entering the United Kingdom

The genus Henipavirus includes Hendra virus (HeV) and Nipah virus (NiV), for which fruit bats (particularly those of the genus Pteropus) are considered to be the wildlife reservoir. The recognition of henipaviruses occurring across a wider geographic and host range suggests the possibility of the virus entering the United Kingdom (UK). To estimate the likelihood of henipaviruses entering the UK, a qualitative release assessment was undertaken. To facilitate the release assessment, the world was divided into four zones according to location of outbreaks of henipaviruses, isolation of henipaviruses, proximity to other countries where incidents of henipaviruses have occurred and the distribution of Pteropus spp. fruit bats. From this release assessment, the key findings are that the importation of fruit from Zone 1 and 2 and bat bushmeat from Zone 1 each have a Low annual probability of release of henipaviruses into the UK. Similarly, the importation of bat meat from Zone 2, horses and companion animals from Zone 1 and people travelling from Zone 1 and entering the UK was estimated to pose a Very Low probability of release. The annual probability of release for all other release routes was assessed to be Negligible. It is recommended that the release assessment be periodically re-assessed to reflect changes in knowledge and circumstances over time.

Assessing the risks of West Nile virus-infected mosquitoes from transatlantic aircraft: implications for disease emergence in the United Kingdom

The number of West Nile virus (WNV)-infected mosquitoes aboard aircraft from the United States that arrive in the United Kingdom each summer was determined using a quantitative risk assessment. In the worst-case scenario, when WNV levels in mosquitoes are high (at epidemic levels) the probability of at least one WNV-infected mosquito being introduced into the United Kingdom was predicted to be 0.99. During these periods, a mean of 5.2 infected mosquitoes were estimated to be aboard flights from the United States to the United Kingdom during May to October, with 90% certainty that the exact value lies between one and ten mosquitoes. Heathrow airport was predicted to receive the majority of the infected mosquitoes (72.1%). Spatial analysis revealed the region surrounding Heathrow satisfies the criteria for potential WNV exposure as both WNV-competent mosquitoes and susceptible wild bird species are present. This region is, therefore, recommended for targeted, risk-based surveillance of WNV-infected mosquitoes in addition to an increased awareness of the risks to horses, birds and humans.

Impact of climate change on risk of incursion of Crimean-Congo haemorrhagic fever virus in livestock in Europe through migratory birds

AIMS

To predict the risk of incursion of Crimean-Congo haemorrhagic fever virus (CCHFV) in livestock in Europe introduced through immature Hyalomma marginatum ticks on migratory birds under current conditions and in the decade 2075-2084 under a climate-change scenario.

METHODS AND RESULTS

A spatial risk map of Europe comprising 14 282 grid cells (25 × 25 km) was constructed using three data sources: (i) ranges and abundances of four species of bird which migrate from sub-Saharan Africa to Europe each spring, namely Willow warbler (Phylloscopus trochilus), Northern wheatear (Oenanthe oenanthe), Tree pipit (Anthus trivialis) and Common quail (Coturnix coturnix); (ii) UK Met Office HadRM3 spring temperatures for prediction of moulting success of immature H. marginatum ticks and (iii) livestock densities. On average, the number of grid cells in Europe predicted to have at least one CCHFV incursion in livestock in spring was 1·04 per year for the decade 2005-2014 and 1·03 per year for the decade 2075-2084. In general with the assumed climate-change scenario, the risk increased in northern Europe but decreased in central and southern Europe, although there is considerable local variation in the trends.

CONCLUSIONS

The absolute risk of incursion of CCHFV in livestock through ticks introduced by four abundant species of migratory bird (totalling 120 million individual birds) is very low. Climate change has opposing effects, increasing the success of the moult of the nymphal ticks into adults but decreasing the projected abundance of birds by 34% in this model.

SIGNIFICANCE AND IMPACT OF THE STUDY

For Europe, climate change is not predicted to increase the overall risk of incursion of CCHFV in livestock through infected ticks introduced by these four migratory bird species.

Operation Hernia to Ghana

Inguinal hernia repair and Caesarian section are the two most commonly occurring operations in Africa. Trained surgeons are few, distances between hospitals are large and strangulated hernia is the most common cause of intestinal obstruction. Numerous deaths and cases of permanent disability occur because patients with inguinal hernias requiring elective or urgent surgery are not properly cared for, or they do not actually reach hospital. Operation Hernia was a humanitarian mission between the European Hernia Society and the Plymouth-Takoradi (Ghana) Link conceived specifically to treat and teach groin hernia surgery in the Western region of Ghana.

Some issues in resolution of diagnostic tests using an imperfect gold standard

As a subject's true disease status is seldom known with certainty, it is necessary to compare the performance of new diagnostic tests with those of a currently accepted but imperfect 'gold standard'. Errors made by the gold standard mean that the sensitivity and specificity calculated for the new test are biased, and do not correctly estimate the new method's sensitivity and specificity. The traditional approach to this problem was 'discrepant resolution', in which the subjects for whom the two methods disagreed were subjected to a third 'resolver' test. Recent work has pointed out that this does not automatically solve the problem. A sounder approach goes beyond the discordant test results and tests at least some of the subjects with concordant results with the resolver also. This leaves some issues unresolved. One is the basic question of the direction of biases in various estimators. We point out that this question does not have a simple universal answer. Another issue, if one is to test a sample of the subjects with concordant results rather than all cases, is how to compute estimates and standard errors of the measures of test performance, notably sensitivity and specificity of the test method relative to the resolver. Expressions for these standard errors are given and illustrated with a numeric example. It is shown that using just a sample of subjects with concordant results may lead to great savings in assays. The design issue of how many concordant cells to test depends on the numbers of concordants and discordants. The formulae given show how to evaluate impact of different choices for these numbers and hence settle on a design that gives the required precision of estimates.

Epidemiology, etiology, and impact of traveler's diarrhea in Jamaica

CONTEXT

Traveler's diarrhea (TD) can incapacitate travelers. Characteristics of TD could be helpful in identifying individuals who might benefit from a vaccine against TD.

OBJECTIVE

To determine epidemiology, etiology, and impact of TD in Jamaica. Design Two-armed, cross-sectional survey conducted between March 1996 and May 1997.

SETTING

Sangster International Airport and 10 hotels in Montego Bay area, Jamaica.

SUBJECTS

To investigate epidemiology and impact, 30369 short-term visitors completed a questionnaire just before boarding their homebound aircrafts. To investigate etiology, 322 patients (hotel guests) with TD provided stool samples.

MAIN OUTCOME MEASURES

Attack and incidence rates of reported diarrhea and of classically defined TD (> or =3 unformed stool samples in 24 hours and > or =1 accompanying symptom), incapacity, risk factors, and etiology.

RESULTS

The attack rate for diarrhea was 23.6% overall, with 11.7% having classically defined TD. For a mean duration of stay of 4 to 7 days, the incidence rate was 20.9% (all TD) and 10.0% (classic TD). Among airport respondents, the incapacity lasted a mean of 11.6 hours. Less than 3% of all travelers avoided potentially high-risk food and beverages. The most frequently detected pathogens were enterotoxigenic Escherichia coli, Rotavirus, and Salmonella species.

CONCLUSIONS

A realistic plan for reducing TD is needed. Preventive measures such as the improvement of hygienic conditions at the destination, and/or the development of vaccines against the most frequent pathogens associated with TD may contribute toward achieving this goal.

Use of granulocyte colony-stimulating factor (G-CSF) in patients receiving myelosuppressive chemotherapy for the treatment of cancer. Provincial Systemic Treatment Disease Site Group

GUIDELINE QUESTIONS

1) Does G-CSF reduce the incidence of important adverse clinical outcomes due to infections in patients with cancer treated with myelosuppressive therapy? 2) Does G-CSF allow maintenance of the chemotherapy dose with the goal of improving survival?

OBJECTIVE

To evaluate the evidence for the role of G-CSF in patients receiving myelosuppressive chemotherapy for the treatment of cancer.

OUTCOMES

Clinical outcomes reflecting events that may affect quality of life and/or resource utilization (e.g., rates and duration of hospitalization, antibiotic use); outcomes reflecting the effect of treatment on infection rates, tumour response and survival and those related to the biological effect of G-CSF.

PERSPECTIVE (VALUES)

Evidence was selected, reviewed and synthesized by members of the Provincial Systemic Treatment Disease Site Group (DSG) of the Cancer Care Ontario Practice Guidelines Initiative. Drafts of this document have been circulated and reviewed by members of the Systemic Treatment DSG. The DSG comprises medical oncologists, pharmacists, supportive care personnel and administrators. Evaluation by clinicians was considered in the final practice guideline. Community representatives did not participate in the development of this report but will in future reports. Guidelines approval does require participation by community representatives.

QUALITY OF EVIDENCE

Two published guidelines and an update of one guideline were identified. Ten eligible randomized controlled trials published in English were included.

BENEFITS

A meta-analysis of data from 8 trials showed that the odds of experiencing febrile neutropenia with G-CSF were significantly reduced (odds ratio 0.38; 95% confidence interval [CI] 0.27 to 0.52; p < 0.00001). G-CSF reduced the risk of febrile neutropenia by 34% (risk ratio 0.66; 95% CI 0.51 to 0.86; p = 0.0015). The use of G-CSF was associated with a significant reduction in antibiotic usage and days spent in hospital in 2 trials and had no effect in the other 4 in which it was measured. Five trials reported no difference in overall median survival, with 2 small trials detecting a significant increase related to G-CSF. However, further research is necessary to confirm these results.

HARMS

The toxic effects of G-CSF are relatively mild. The most consistent clinical symptom attributed to G-CSF is bone pain, reported in incidence rates ranging from 20% to 50% in 3 trials. Except for one case, reported bone pain was mild.

PRACTICE GUIDELINE

In cancer patients receiving myelosuppressive chemotherapy, granulocyte colony-stimulating factor (G-CSF) may be beneficial for some patients. If a reduction in the number of febrile neutropenic episodes, or in the duration of such episodes, is expected to improve quality of life, then G-CSF is a reasonable treatment option for selected patients. A clear justification for the use of G-CSF should be stated. If the objective of using G-CSF is to maintain dose intensity of antitumour agents, then G-CSF can be recommended where reduction in dose intensity has been shown in randomized controlled trials to reduce survival or disease-free survival. Although the evidence is weaker, the Systemic Treatment DSG would support the practice endorsed by other guidelines (American Society of Clinical Oncology, Ontario Drug Benefit Plan) and would recommend G-CSF for patients receiving potentially curative chemotherapy: i) as primary prophylaxis; that is, where dose reductions below a specified level are required because of a known high risk of febrile neutropenia, or ii) as secondary prophylaxis in patients receiving chemotherapy of established efficacy who have suffered a prior serious episode of febrile neutropenia due to the same chemotherapy regimen. The exact cut-off for dose reductions is unknown at this time and ought to be left to the judgement of the clinician. In general, the use of G-CSF for dose reductions lower than 20% is not recommended. (ABSTRACT TRUNCATED)

Effects of chronic exposure to sublethal concentrations of lead acetate on heme synthesis and immune function in red-tailed hawks

Red-tailed hawks were exposed to sublethal levels of lead acetate for periods of 3 or 11 weeks. Alterations in the heme biosynthetic pathway were demonstrated after the first week of exposure to 0.82 mg lead per kilogram body weight per day. Activity of erythrocyte porphobilinogen synthase (aminolevulinic acid dehydratase) was depressed significantly and did not return to normal levels until 5 weeks after the termination of lead treatments. A rapid and relatively brief increase in erythrocyte free protoporphyrin and a slower but more prolonged increase in its zinc complex were also demonstrated with exposure to this dose of lead for 3 weeks. Less substantial decreases in hematocrit and hemoglobin levels occurred but only in the longer experiment with exposure to higher lead levels. Short term, low level lead exposure did not effect immune function significantly in the hawks, as measured by antibody titers to foreign red blood cells or by the mitogenic stimulation of T-lymphocytes. Increased lead exposure produced a significant decrease in the mitogenic response but had no effect on antibody titers.

Iron deficiency among incarcerated juvenile delinquents

A population of 163 incarcerated delinquents (126 males and 37 females aged 12-18 years) was studied to determine the prevalence of iron deficiency and to compare hemoglobin (Hgb), mean corpuscular volume (MCV), serum ferritin (SF), and erythrocyte protoporphyrin/hemoglobin (EP/Hgb) as predictors of response to iron therapy. Thirty-two percent of females and 6% of males had SF less than or equal to 12 ng/ml; 51% of females and 24% of males had SF less than or equal to 20 ng/ml. The mean SF was 17.7 ng/ml for females and 29.2 ng/ml for males. Of the 163 subjects, 53 were at risk for iron deficiency based on SF, Hgb, EP/Hgb, or MCV criteria. Twenty-one completed treatment with iron, and nine had greater than 1 g rise in Hgb. The following tests identified responders: SF less than or equal to 12 ng/ml-5/9; SF less than or equal to 20 ng/ml-9/9; Hgb less than or equal to third percentile-4/9; Hgb less than or equal to tenth percentile-7/9; MCV less than or equal to tenth percentile-2/9; EP/Hgb greater than or equal to 3.0 micrograms/g Hgb-2/9; EP/Hgb greater than or equal to 2.5 micrograms/g Hgb-4/9. Serum ferritin less than or equal to 20 ng/ml had a false positive rate of 57%; Hgb less than or equal to tenth percentile and EP/Hgb greater than or equal to 2.5 mu g/g Hgb had no false positives. The significance of the high prevalence of iron deficiency among a population of incarcerated adolescents is not clear.(ABSTRACT TRUNCATED AT 250 WORDS)

Bovine protoporphyria: the first nonhuman model of this hereditary photosensitizing disease

Protoporphyria, a photosensitizing disease documented only in humans, was transmitted as a recessive trait to seven female calves. Cutaneous lesions were extensive, and erythrocyte and fecal protoporphyrin concentrations exceeded by far those of human protoporphyria. Average ferrochelatase activity was decreased to one-half of normal in the liver of carriers, and to about one-tenth of normal in liver, kidney, heart, spleen, lung, and marrow of protoporphyrics.

Chromatography on Florisil in the quantitative estimation of urinary and other porphyrins

We describe the use of Florisil chromatography to purify and fractionate porphyrins into uro-, copro-, and protoporphyrins before their measurement by quantitative fluorometry. Porphyrinogens in fresh urine may be rapidly oxidized to porphyrins by chloranil, or slowly in weakly alkaline solution, before the sample is applied to the Florisil column. Aliquots of the separate ammoniacal eluates may be lyophilized for additional fractionation by direct thin-layer chromatographic analysis if desired. The behavior of delta-aminolevulinic acid, porphobilinogen, and other pyrrole compounds in this system is also described.

Chromatography on Florisil in the quantitative estimation of urinary and other porphyrins

We describe the use of Florisil chromatography to purify and fractionate porphyrins into uro-, copro-, and protoporphyrins before their measurement by quantitative fluorometry. Porphyrinogens in fresh urine may be rapidly oxidized to porphyrins by chloranil, or slowly in weakly alkaline solution, before the sample is applied to the Florisil column. Aliquots of the separate ammoniacal eluates may be lyophilized for additional fractionation by direct thin-layer chromatographic analysis if desired. The behavior of delta-aminolevulinic acid, porphobilinogen, and other pyrrole compounds in this system is also described.

Abortion: an open letter

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Canadian doctors have acted responsibly in confronting their several dilemmas

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At the family level

Most parents today are frightened by the idea that youth is hostile and powerful. In order to cope with their fear they become too permissive; they do not offer their children any guidelines and therefore give the impression of abandoning them. Parent education in the problems of adolescence (physical and mental) is a prerequisite for good "parenting", as is a sense of humour and a solid opinion of one's own, regardless of its popularity.

THE NORMAL BLOOD CHEMISTRY OF THE BEAVER (CASTOR CANADENSIS): A. PACKED-CELL VOLUME, SEDIMENTATION RATE, HEMOGLOBIN, ERYTHROCYTE DIAMETER, AND BLOOD CELL COUNTS

Packed-cell volume, sedimentation rate, hemoglobin, red blood cell count, white blood cell count, differential count, and red cell diameter have been determined on blood samples taken from 22 beavers. The various values obtained are in general comparable with those reported for the other rodents. Exceptions to this general agreement were noted in the much higher sedimentation rate and slightly larger red cell diameter of beaver blood.