A Type 1 Diabetes Genetic Risk Score Predicts Progression of Islet Autoimmunity and Development of Type 1 Diabetes in Individuals at Risk

OBJECTIVE

We tested the ability of a type 1 diabetes (T1D) genetic risk score (GRS) to predict progression of islet autoimmunity and T1D in at-risk individuals.

RESEARCH DESIGN AND METHODS

We studied the 1,244 TrialNet Pathway to Prevention study participants (T1D patients' relatives without diabetes and with one or more positive autoantibodies) who were genotyped with Illumina ImmunoChip (median [range] age at initial autoantibody determination 11.1 years [1.2-51.8], 48% male, 80.5% non-Hispanic white, median follow-up 5.4 years). Of 291 participants with a single positive autoantibody at screening, 157 converted to multiple autoantibody positivity and 55 developed diabetes. Of 953 participants with multiple positive autoantibodies at screening, 419 developed diabetes. We calculated the T1D GRS from 30 T1D-associated single nucleotide polymorphisms. We used multivariable Cox regression models, time-dependent receiver operating characteristic curves, and area under the curve (AUC) measures to evaluate prognostic utility of T1D GRS, age, sex, Diabetes Prevention Trial-Type 1 (DPT-1) Risk Score, positive autoantibody number or type, HLA DR3/DR4-DQ8 status, and race/ethnicity. We used recursive partitioning analyses to identify cut points in continuous variables.

RESULTS

Higher T1D GRS significantly increased the rate of progression to T1D adjusting for DPT-1 Risk Score, age, number of positive autoantibodies, sex, and ethnicity (hazard ratio [HR] 1.29 for a 0.05 increase, 95% CI 1.06-1.6; P = 0.011). Progression to T1D was best predicted by a combined model with GRS, number of positive autoantibodies, DPT-1 Risk Score, and age (7-year time-integrated AUC = 0.79, 5-year AUC = 0.73). Higher GRS was significantly associated with increased progression rate from single to multiple positive autoantibodies after adjusting for age, autoantibody type, ethnicity, and sex (HR 2.27 for GRS >0.295, 95% CI 1.47-3.51; P = 0.0002).

CONCLUSIONS

The T1D GRS independently predicts progression to T1D and improves prediction along T1D stages in autoantibody-positive relatives.

Efficacy of a new collection procedure for preventing bacterial contamination of whole-blood donations

BACKGROUND

Transfusion-related bacterial contamination is a serious problem. The introduction of bacteria into donations at the collection stage seems frequent, despite well-conducted phlebotomy site preparation. Additional preventive measures are required.

STUDY DESIGN AND METHODS

The aim of this study was to assess the potential efficacy of excluding the first 15 mL of blood to reduce the bacterial contamination of donations. A special device allowed the aseptic collection of two samples at the beginning of donation: S1 (first 15 mL) and S2 (next 15 mL). Bacteriologic cultures of S1 and S2 were performed by using an automated system. The procedure's efficacy was measured by the proportion of positive donations in S1 that were then negative in S2.

RESULTS

S1 and/or S2 were positive in 76 (2.2%) of 3385 donations. In about three-fourths of the culture-positive donations, contamination was detected in the first 15-mL sample only. Gram-positive cocci accounted for 81 percent of species, gram-positive bacilli for 14 percent, and gram-negative bacilli for 5 percent. The new procedure would have prevented the introduction of bacteria in 55 donations, reducing to 0.6 percent the risk of contamination from the first 15 mL collected.

CONCLUSION

Although the final effect on blood component bacterial contamination rates cannot be derived from the study, excluding the first 15 mL of blood may reduce the rate of bacterial contamination in donations.

Emergency and surgery services of primary hospitals in the United Republic of Tanzania

OBJECTIVE

The primary objective was to evaluate the capacity of first-referral health facilities in Tanzania to perform basic surgical procedures. The intent was to assist in planning strategies for universal access to life-saving and disability-preventing surgical services.

DESIGN

Cross-sectional survey.

SETTING

First-referral health facilities in the United Republic of Tanzania.

PARTICIPANTS

48 health facilities.

MEASURES

The WHO Tool for Situational Analysis to Assess Emergency and Essential Surgical Care was employed to capture a health facility's capacity to perform basic surgical (including obstetrics and trauma) and anaesthesia interventions by investigating four categories of data: infrastructure, human resources, interventions available and equipment. The tool queried the availability of eight types of care providers, 35 surgical interventions and 67 items of equipment.

RESULTS

The 48 facilities surveyed served 18.6 million residents (46% of the population). Supplies for basic airway management were inconsistently available. Only 42% had consistent access to oxygen, and only six functioning pulse oximeters were located in all facilities surveyed. 37.5% of facilities reported both consistent running water and electricity. While very basic interventions (suturing, wound debridement, incision and drainage) were provided in nearly all facilities, more advanced life-saving procedures including chest tube thoracostomy (30/48), open fracture management (29/48) and caesarean section delivery (32/48) were not consistently available.

CONCLUSIONS

Based on the results in this WHO country survey, significant gaps exist in the capacity for emergency and essential surgical services in Tanzania including deficits in human resources, essential equipment and infrastructure. The information in this survey will provide a foundation for evidence-based decisions in country-level policy regarding the allocation of resources and provision of emergency and essential surgical services.

The French haemovigilance system

Haemovigilance was part of the reform of the French transfusion system. The haemovigilance network is now operational with approximately 4600 transfusion incidents reported annually. Immediate incidents observed within 8 days after transfusion account for 85% of the reports. A cause cannot be identified in 41% of these, usually concerning minor clinical incidents with transient fever and/or shivers. An allergic reaction is described in 31% of transfusion reactions. Immunological conflicts account for 18% and bacteria associated transfusion reactions for 6%. The importance of bacteria associated transfusion reactions, the first identified cause of death associated with transfusion is one of the findings of haemovigilance. Improvement in the haemovigilance systems aims at obtaining better descriptions of transfusion incidents, standardisation of severity and imputability assessment and definitions of denominators such as the actual number of recipients. Delayed incidents will ultimately provide a true vision of post transfusion immunisation and infection The improvement of haemovigilance now considered as part of transfusion medicine practice is a continuous process.

Multivariate analysis of determinants of bacterial contamination of whole-blood donations

BACKGROUND AND OBJECTIVES

Introduction of bacteria into blood components at the collection stage seems to be a frequent occurrence. We therefore assessed determinants of bacterial contamination of whole-blood donations to gain insight into contamination mechanisms and direct prevention.

MATERIALS AND METHODS

A cross-sectional study was carried out on donors accepted for whole-blood donation in four French blood banks. Each blood bank used its own two-stage procedure for phlebotomy site preparation. Contamination was identified by culturing two 15-ml samples (collected aseptically at the outset of donation) in a BacT/Alert 240 system. Determinants were assessed by logistic regression analysis.

RESULTS

Bacterial contamination, mainly by skin flora, occurred in 76 (2.2%) out of 3385 donations. Significant determinants were as follows: the blood bank (odds ratio [OR] range = 3.0-5.6, P < 0.001); lack of repetition of scrub (OR = 2.7, P = 0.032); and donor age > 35 years (OR = 1.8, P = 0.036).

CONCLUSION

Systematic scrub repetition should be implemented to reduce bacterial contamination by skin flora at the collection stage. Further research is required to clarify the role of different antiseptic agents and of donor age.

Effectiveness of contingent screening for placenta accreta spectrum disorders based on persistent low-lying placenta and previous uterine surgery

OBJECTIVES

Maternal mortality related to placenta accreta spectrum (PAS) disorders remains substantial when diagnosed unexpectedly at delivery. The aim of this study was to evaluate the effectiveness of a routine contingent ultrasound screening program for PAS.

METHODS

This was a retrospective study of data obtained between 2009 and 2019, involving two groups: a screening cohort of unselected women attending for routine mid-trimester ultrasound assessment and a diagnostic cohort consisting of women referred to the PAS diagnostic service with a suspected diagnosis of PAS. In the screening cohort, women with a low-lying placenta at the mid-trimester assessment were followed up in the third trimester, and those with a persistent low-lying placenta (i.e. placenta previa) and previous uterine surgery were referred to the PAS diagnostic service. Ultrasound assessment by the PAS diagnostic service consisted of two-dimensional grayscale and color Doppler ultrasonography, and women with a diagnosis of PAS were usually managed with conservative myometrial resection. The final diagnosis of PAS was based on a combination of intraoperative clinical findings and histopathological examination of the surgical specimen.

RESULTS

In total, 57 179 women underwent routine mid-trimester fetal anatomy assessment, of whom 220 (0.4%) had a third-trimester diagnosis of placenta previa. Seventy-five of these women were referred to the PAS diagnostic service because of a history of uterine surgery, and 21 of 22 cases of PAS were diagnosed correctly (sensitivity, 95.45% (95% CI, 77.16-99.88%) and specificity, 100% (95% CI, 99.07-100%)). Univariate analysis demonstrated that parity ≥ 2 (odds ratio (OR), 35.50 (95% CI, 6.90-649.00)), two or more previous Cesarean sections (OR, 94.20 (95% CI, 22.00-656.00)) and placenta previa (OR, 20.50 (95% CI, 4.22-369.00)) were the strongest risk factors for PAS. In the diagnostic cohort, there were 173 referrals, with one false-positive and three false-negative diagnoses, resulting in a sensitivity of 96.63% (95% CI, 90.46-99.30%) and a specificity of 98.81% (95% CI, 93.54-99.97%).

CONCLUSIONS

A contingent screening strategy for PAS is both feasible and effective in a routine healthcare setting. When linked to a PAS diagnostic and surgical management service, adoption of such a screening strategy has the potential to reduce the maternal morbidity and mortality associated with this condition. However, larger prospective studies are necessary before implementing this screening strategy into routine clinical practice. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

The French haemovigilance system

Haemovigilance is a national system of surveillance and alarm, from blood collection to the follow-up of the recipients, gathering and analysing all untoward effects of blood transfusion in order to correct their cause and prevent recurrence. In France haemovigilance was created by law and notification of transfusion incidents is a legal obligation. The haemovigilance network associates local correspondents in each hospital and blood centre with regional co-ordinators and is centralised by the Agence Française du Sang. After 4 years the incident reporting rate is 2.3 per 1,000 allogeneic blood components transfused, justifying for example increased efforts in the prevention of bacteria-associated transfusion reactions, haemolytic transfusion reactions or vascular overload. However, haemovigilance still has to be strenghtened by improved information management or further progress in standardisation from one region to the other. The most important factor of success is collaboration between blood centres and hospitals. Haemovigilance clearly is the ultimate quality indicator of a transfusion service.

Radiocesium body burdens in immigrants to Israel from areas of the Ukraine, Belarus and Russia near Chernobyl

Of the 500,000 immigrants from the former Soviet Union who came to Israel during 1990-1993, about 100,000 are estimated to have come from radiocontaminated areas near Chernobyl. These people were subject to chronic uptake of environmental radiocesium over protracted periods. During October-November 1991, a joint Israeli-Canadian investigation measured radiocesium body burdens in immigrants to Israel from the Ukraine, Belarus, and the southern Russian republic in order to provide factual information on radiocesium levels to concerned immigrants and to relate the body burdens to the geographic area of residence before coming to Israel. Assessments were made of 137Cs body burdens in 1,228 volunteer men, women, and children. These measurements were accompanied by medical assessments based on clinical histories and examinations. Radiocesium levels were strongly dependent on the duration of residence in Israel, with the highest levels being found in the most recent immigrants. The maximum level, extrapolated back to the time of leaving the former Soviet Union, was estimated to be about 0.83 kBq (10.3 Bq kg-1). Of the most recent immigrants from the Kiev region (< 101 days in Israel), only 15% had back extrapolated body burdens > 50 Bq, whereas 53% of those coming from Gomel and other towns in the contaminated zones (> 3.7 x 10(10) Bq km-2 of radiocesium) had detectable levels > 50 Bq. People coming from the latter region had significantly higher body burdens as compared to those from the former, in accordance with the higher degree of ground radiocesium contamination reported for the latter region. Women and children showed considerably lower total radiocesium content in comparison to men. All radiocesium body burdens at the time of measurement were too low to be of health concern.

Clinical performance of a specific granulocyte colony stimulating factor ELISA to determine its concentration in follicular fluid as a predictor of implantation success during in vitro fertilization

This study aimed to demonstrate the clinical performance of an ultra-sensitive follicular fluid (FF) granulocyte colony stimulating factor (G-CSF) immunoassay to confirm previous work, indicating a correlation between FF G-CSF concentration and live birth potential of the corresponding embryo after in vitro fertilization. This study was a noninterventional, prospective, diagnostic clinical multicentric study conducted between August 2012 and January 2014 with 396 single embryo transfers (SETs) from 278 subjects. During oocyte retrieval, FF was individually collected. Embryo morphology and implantation success were evaluated. The implantation success rate in the high G-CSF group (32.3%) was higher than the overall rate (27.5%). Similarly, for embryos with optimal morphology, implantation success rates were highest among those in the high G-CSF concentration category (34.5%) compared with low (19.6%) and intermediate (29.8%) G-CSF concentration categories. Significant differences in mean G-CSF concentrations were observed between the study sites. To minimize bias, analyses were repeated using data from the center with the largest number of SETs. In alignment with the overall analysis, this center demonstrated a 43% greater probability of implantation for optimal embryos with high G-CSF compared to the general implantation rate among optimal embryos and a 327% increase compared with the implantation rate of optimal embryos with low G-CSF.

Transmission of HIV by transfusion of HIV-screened blood: the value of a national register. The 'Recipients' Study Group of the French Society of Blood Transfusion

A National Register of transfusion-transmitted infections was opened by the French Society of Blood Transfusion on 1 October, 1986. Out of 54 initially reported cases of HIV-infection, allegedly transmitted by blood components, further investigation could be completed in 33 cases. The transfusional origin of contamination was considered as established or probable in 28/33 cases, either because a potentially infectious unit was identified among those transfused to the recipient (23/28), or because the recipient was known to be seronegative before transfusion (5/28), or both (10/28). In 5/33 cases transfusion was considered as presumably responsible for contamination because no other risk factor was found in the recipient. Among the 33 documented cases of HIV-transmission by screened blood, 29 (88%) occurred between 1985 and 1987, and four (12%) during 1988. Out of 19 implicated donors later found seropositive, 16 belonged to a high-risk group for HIV-infection. The majority of HIV-infections occurred as a consequence of blood donation in the window period between contamination and the appearance of detectable antibodies in the donor's serum (11/19). In three instances, however, human and operational errors led to the release of seropositive units. We conclude that the main value of this Register is to provide a potential trend-indicator of transfusion-related infectious risks, to allow objective documentation of reported cases and to contribute to the improvement of blood transfusion practice.

How the bacterial plant pathogen Xanthomonas campestris pv. vesicatoria conquers the host

Abstract Xanthomonas campestris pv. vesicatoria (Xcv) is the causal agent of bacterial spot disease on pepper and tomato. Pathogenicity on susceptible plants and the induction of the hypersensitive reaction (HR) on resistant plants requires a number of genes, designated hrp, most of which are clustered in a 23-kb chromosomal region. Nine hrp genes encode components of a type III protein secretion apparatus that is conserved in Gram-negative plant and animal pathogenic bacteria. We have recently demonstrated that Xcv secretes proteins into the culture medium in a hrp-dependent manner. Substrates of the Hrp secretion machinery are pathogenicity factors and avirulence proteins, e.g. AvrBs3. The AvrBs3 protein governs recognition, i.e. HR induction, when bacteria infect pepper plants carrying the corresponding resistance gene Bs3. Intriguingly, the AvrBs3 protein contains eukaryotic signatures such as nuclear localization signals (NLS), and has been shown to act inside the plant cell. We postulate that AvrBs3 is transferred into the plant cell via the Hrp type III pathway and that recognition of AvrBs3 takes place in the plant cell nucleus.

Characterization of a human Y chromosome Pvu II repeated sequence

The human Y chromosome carries numerous copies of a tandemly repeated Pvu II sequence, 2.4 kb long. These sequences are specific to humans, and are present in a much smaller amount in the DNA of females. They are localized on the long arm of the Y chromosome. We have compared this sequence with the Hae III 2.1 kb Y-specific repeated sequence, already described.

Assessment of combined risk to pesticide residues through dietary exposure

Plant protection products (PPPs) are preparations intended to protect plants and their products including one or more active substances. The use of PPPs may cause direct or indirect risks. Residues that can remain in or on food might pose a danger to human health through consumption and acute or/and chronic exposure. Authorisation of active substances and PPPs are decided at European and national level, respectively. Risk assessment of dietary exposure to residues of PPPs is regulated by a very extensive legal framework, ensuring consumer safety. The review and evaluation of the residue section of active substance monographs and the dossiers for PPP authorisations within the French Agency for Food, Environmental and Occupational Health & Safety (ANSES) helped gain hands‐on experience on food risk assessment, as previewed in the framework of the European Food Risk Assessment Fellowship Programme (EU‐FORA). The programme also focused on the cumulative effects of acute exposure to pesticides in food on the human nervous system using probabilistic methodology and it was in continuation of the work carried out by ANSES and the regulated products department residue unit. Using the European Database for processing factors for pesticides in food was one of the main challenges in order to approach a more realistic scenario of exposure. The probabilistic methodology followed was used in accordance with the European Food Safety Authority harmonised guidance.