Evaluation of C1q Status and Titer of De Novo Donor-Specific Antibodies as Predictors of Allograft Survival

De novo donor-specific antibodies (dnDSAs) that develop after renal transplantation are independent predictors of allograft loss. However, it is unknown if dnDSA C1q status or titer at the time of first detection can independently predict allograft loss. In a consecutive cohort of 508 renal transplant recipients, 70 developed dnDSAs. Histologic and clinical outcomes were correlated with the C1q assay or dnDSA titer. C1q positivity correlated with dnDSA titer (p < 0.01) and mean fluorescence intensity (p < 0.01) and was more common in class II versus class I dnDSAs (p < 0.01). C1q status correlated with tubulitis (p = 0.02) and C4d status (p = 0.03) in biopsies at the time of dnDSA development, but not T cell-mediated rejection (TCMR) or antibody-mediated rejection (ABMR). De novo DSA titer correlated with Banff g, i, t, ptc, C4d scores, TCMR (p < 0.01) and ABMR (p < 0.01). Post-dnDSA graft loss was observed more frequently in recipients with C1q-positve dnDSA (p < 0.01) or dnDSA titer ≥ 1:1024 (p ≤ 0.01). However, after adjustment for clinical phenotype and nonadherence in multivariate models, neither C1q status nor dnDSA titer were independently associated with allograft loss, questioning the utility of these assays at the time of dnDSA development.

Multiple Cardioembolic Strokes Caused by Caseous Calcification of the Mitral Annulus

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Mitral annular calcification (MAC) is a common echocardiographic finding, estimated at around 14%, and occurs especially in elderly women.

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Caseous calcification of the mitral annulus (CCMA) is a rare subvariant of MAC, with an echocardiographic prevalence of 0.6% and necropsy prevalence of about 2.3%.

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CCMA, just like MAC, is believed to be associated with a high calcium score, coronary artery disease, aortic valve disease, atrial fibrillation, and hypertension.

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CCMA can be confused echocardiographically with infective endocarditis, tumors, and cysts.

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The decision for surgical treatment of CCMA is based on clinical judgment with factors such as valvular dysfunction and/or the propensity for stroke.

A Controlled Trial of Iron Therapy in Sideropenia

It has been shown that there is a high incidence of latent iron deficiency (sideropenia) in the female population. To assess the role of this deficiency as a cause of symptoms a double blind trial of iron and placebo therapy was carried out on 20 sideropenic women presenting with symptoms.

The incidence of all the symptoms studied fell and there was no significant difference between iron and placebo in producing improvement.

A significant rise in haemoglobin level occurred only in response to iron therapy and this was reversed on cessation of iron. No significant changes in haemoglobin occurred in response to the placebo.

It has been concluded that while iron has no specific effect on the symptoms associated with sideropenia, it will produce a significant rise in haemoglobin level, reverse biochemical defects and, in a minority, prevent development of iron deficiency anaemia.

Knee surgery and its evidence base

INTRODUCTION

Evidence driven orthopaedics is gaining prominence. It enables better management decisions and therefore better patient care. The aim of our study was to review a selection of the leading publications pertaining to knee surgery to assess changes in levels of evidence over a decade.

METHODS

Articles from the years 2000 and 2010 in The Knee, the Journal of Arthroplasty, Knee Surgery, Sports Traumatology, Arthroscopy, the Journal of Bone and Joint Surgery (American Volume) and the Bone and Joint Journal were analysed and ranked according to guidelines from the Centre for Evidence-Based Medicine. The intervening years (2003, 2005 and 2007) were also analysed to further define the trend.

RESULTS

The percentage of high level evidence (level I and II) studies increased albeit without reaching statistical significance. Following a significant downward trend, the latter part of the decade saw a major rise in levels of published evidence. The most frequent type of study was therapeutic.

CONCLUSIONS

Although the rise in levels of evidence across the decade was not statistically significant, there was a significant drop and then rise in these levels in the interim. It is therefore important that a further study is performed to assess longer-term trends. Recent developments have made clear that high quality evidence will be having an ever increasing influence on future orthopaedic practice. We suggest that journals implement compulsory declaration of a published study's level of evidence and that authors consider their study designs carefully to enhance the quality of available evidence.

Simulation as a set-up for technical proficiency: can a virtual warm-up improve live fibre-optic intubation?

BACKGROUND

Fibre-optic intubation (FOI) is an advanced technical skill, which anaesthesia residents must frequently perform under pressure. In surgical subspecialties, a virtual 'warm-up' has been used to prime a practitioner's skill set immediately before performance of challenging procedures. This study examined whether a virtual warm-up improved the performance of elective live patient FOI by anaesthesia residents.

METHODS

Clinical anaesthesia yr 1 and 2 (CA1 and CA2) residents were recruited to perform elective asleep oral FOI. Residents either underwent a 5 min, guided warm-up (using a bronchoscopy simulator) immediately before live FOI on patients with predicted normal airways or performed live FOI on similar patients without the warm-up. Subjects were timed performing FOI (from scope passing teeth to viewing the carina) and were graded on a 45-point skill scale by attending anaesthetists. After a washout period, all subjects were resampled as members of the opposite cohort. Multivariate analysis was performed to control for variations in previous FOI experience of the residents.

RESULTS

Thirty-three anaesthesia residents were recruited, of whom 22 were CA1 and 11 were CA2. Virtual warm-up conferred a 37% reduction in time for CA1s (mean 35.8 (SD 3.2) s vs. 57 (SD 3.2) s, P<0.0002) and a 26% decrease for CA2s (mean 23 (SD 1.7) s vs. 31 (SD 1.7) s, P=0.0118). Global skill score increased with warm-up by 4.8 points for CA1s (mean 32.8 (SD 1.2) vs. 37.6 (SD 1.2), P=0.0079) and 5.1 points for CA2s (37.7 (SD 1.1) vs. 42.8 (SD 1.1), P=0.0125). Crossover period and sequence did not show a statistically significant association with performance.

CONCLUSIONS

Virtual warm-up significantly improved performance by residents of FOI in live patients with normal airway anatomy, as measured both by speed and by a scaled evaluation of skills.

Rates and determinants of progression to graft failure in kidney allograft recipients with de novo donor-specific antibody

Understanding rates and determinants of clinical pathologic progression for recipients with de novo donor-specific antibody (dnDSA), especially subclinical dnDSA, may identify surrogate endpoints and inform clinical trial design. A consecutive cohort of 508 renal transplant recipients (n = 64 with dnDSA) was studied. Recipients (n = 388) without dnDSA or dysfunction had an eGFR decline of -0.65 mL/min/1.73 m(2) /year. In recipients with dnDSA, the rate eGFR decline was significantly increased prior to dnDSA onset (-2.89 vs. -0.65 mL/min/1.73 m(2) /year, p < 0.0001) and accelerated post-dnDSA (-3.63 vs. -2.89 mL/min/1.73 m(2) /year, p < 0.0001), suggesting that dnDSA is both a marker and contributor to ongoing alloimmunity. Time to 50% post-dnDSA graft loss was longer in recipients with subclinical versus a clinical dnDSA phenotype (8.3 vs. 3.3 years, p < 0.0001). Analysis of 1091 allograft biopsies found that dnDSA and time independently predicted chronic glomerulopathy (cg), but not interstitial fibrosis and tubular atrophy (IFTA). Early T cell-mediated rejection, nonadherence, and time were multivariate predictors of IFTA. Independent risk factors for post-dnDSA graft survival available prior to, or at the time of, dnDSA detection were delayed graft function, nonadherence, dnDSA mean fluorescence intensity sum score, tubulitis, and cg. Ultimately, dnDSA is part of a continuum of mixed alloimmune-mediated injury, which requires solutions targeting T and B cells.

Vitamin D, asthma prevalence and asthma exacerbations: a large adult population-based study

BACKGROUND

The impact of low vitamin D status on asthma, asthma morbidity and control is unclear. We aimed to investigate in adults the associations between serum 25-hydroxyvitamin D level and prevalent asthma as well as asthma exacerbations.

METHODS

A cohort of Israeli adults aged 22-50 years with documented vitamin D status were extracted from Clalit Health Services (HMO) between July 1, 2008 and July 1, 2012. Among this population, those with physician-diagnosed asthma and asthma exacerbations were identified. Asthma exacerbations were defined as any of the following: prescription for oral corticosteroids, >5 prescriptions for short acting beta agonists and more than four visits to a physician for asthma. Logistic regression models assessed the associations between vitamin D and both asthma and asthma exacerbations.

RESULTS

Approximately 308 000 members with at least one vitamin D measurement were included in the cohort. Among them, 6.9% (21 237) had physician-diagnosed asthma vs 5.7% in the general population. Serum 25-OHD levels across both groups were similar. However, among those with vitamin D deficiency, the odds of having an exacerbation were 25% greater compared to those with levels in the normal range. This association remained significant after controlling for known confounders.

CONCLUSION

While there was no significant association between vitamin D status and physician-diagnosed asthma, there was a strong association with asthma exacerbations. The presented evidence supports vitamin D screening in the subgroup of asthmatics that are uncontrolled and experience recurrent exacerbations.