Difficulties in screening for peripheral neuropathies in children with diabetes

AIMS

To assess the diagnostic utility of a novel abbreviated monofilament test in comparison with the tuning fork test to detect diabetic peripheral neuropathy in children.

METHODS

A total of 88 children with Type 1 diabetes mellitus were screened for diabetic peripheral neuropathy using the monofilament test and the tuning fork. Nerve conduction studies were performed according to the 'gold standard' for neuropathy. We assessed the diagnostic utility and inter-rater agreement of the two screening methods.

RESULTS

A total of 43 (49%) children (aged 6-18 years) had at least one abnormal nerve conduction study result. Diagnostic utility and inter-rater agreement were very low for both screening methods. The monofilament test yielded a sensitivity of 18% and a specificity of 80%. The tuning fork yielded a sensitivity of 0% and a specificity of 98%.

CONCLUSION

The present study found that an abbreviated monofilament test has low diagnostic utility for the detection of early diabetic peripheral neuropathy because of its low reliability. The problem of reliability needs to be more thoroughly addressed in order to improve the screening procedures in diabetes management in childhood and adolescence.

Impact of intraoperative hypotension and blood pressure fluctuations on early postoperative delirium after non-cardiac surgery

INTRODUCTION

Postoperative delirium is common in older patients. Despite its prognostic significance, the pathophysiology is incompletely understood. Although many risk factors have been identified, no reversible factors, particularly ones potentially modifiable by anaesthetic management, have been identified. The goal of this prospective cohort study was to investigate whether intraoperative hypotension was associated with postoperative delirium in older patients undergoing major non-cardiac surgery.

METHODS

Study subjects were patients >65 years of age, undergoing major non-cardiac surgery, who were enrolled in an ongoing prospective observational study of the pathophysiology of postoperative delirium. Intraoperative blood pressure was measured and predefined criteria were used to define hypotension. Delirium was measured by the Confusion Assessment Method on the first two postoperative days. Data were analysed using t-tests, two-sample proportion tests and ordered logistic regression multivariable models, including correction for multiple comparisons.

RESULTS

Data from 594 patients with a mean age of 73.6 years (sd 6.2) were studied. Of these 178 (30%) developed delirium on day 1 and 176 (30%) on day 2. Patients developing delirium were older, more often female, had lower preoperative cognitive scores, and underwent longer operations. Relative hypotension (decreases by 20, 30, or 40%) or absolute hypotension [mean arterial pressure (MAP)<50 mm Hg] were not significantly associated with postoperative delirium, nor was the duration of hypotension (MAP<50 mm Hg). Conversely, intraoperative blood pressure variance was significantly associated with postoperative delirium.

DISCUSSION

These results showed that increased blood pressure fluctuation, not absolute or relative hypotension, was predictive of postoperative delirium.

Qualitative and quantitative evaluation of rigid and deformable motion correction algorithms using dual-energy CT images in view of application to CT perfusion measurements in abdominal organs affected by breathing motion

OBJECTIVE

To compare six different scenarios for correcting for breathing motion in abdominal dual-energy CT (DECT) perfusion measurements.

METHODS

Rigid [RRComm(80 kVp)] and non-rigid [NRComm(80 kVp)] registration of commercially available CT perfusion software, custom non-rigid registration [NRCustom(80 kVp], demons algorithm) and a control group [CG(80 kVp)] without motion correction were evaluated using 80 kVp images. Additionally, NRCustom was applied to dual-energy (DE)-blended [NRCustom(DE)] and virtual non-contrast [NRCustom(VNC)] images, yielding six evaluated scenarios. After motion correction, perfusion maps were calculated using a combined maximum slope/Patlak model. For qualitative evaluation, three blinded radiologists independently rated motion correction quality and resulting perfusion maps on a four-point scale (4 = best, 1 = worst). For quantitative evaluation, relative changes in metric values, R(2) and residuals of perfusion model fits were calculated.

RESULTS

For motion-corrected images, mean ratings differed significantly [NRCustom(80 kVp) and NRCustom(DE), 3.3; NRComm(80 kVp), 3.1; NRCustom(VNC), 2.9; RRComm(80 kVp), 2.7; CG(80 kVp), 2.7; all p < 0.05], except when comparing NRCustom(80 kVp) with NRCustom(DE) and RRComm(80 kVp) with CG(80 kVp). NRCustom(80 kVp) and NRCustom(DE) achieved the highest reduction in metric values [NRCustom(80 kVp), 48.5%; NRCustom(DE), 45.6%; NRComm(80 kVp), 29.2%; NRCustom(VNC), 22.8%; RRComm(80 kVp), 0.6%; CG(80 kVp), 0%]. Regarding perfusion maps, NRCustom(80 kVp) and NRCustom(DE) were rated highest [NRCustom(80 kVp), 3.1; NRCustom(DE), 3.0; NRComm(80 kVp), 2.8; NRCustom(VNC), 2.6; CG(80 kVp), 2.5; RRComm(80 kVp), 2.4] and had significantly higher R(2) and lower residuals. Correlation between qualitative and quantitative evaluation was low to moderate.

CONCLUSION

Non-rigid motion correction improves spatial alignment of the target region and fit of CT perfusion models. Using DE-blended and DE-VNC images for deformable registration offers no significant improvement.

ADVANCES IN KNOWLEDGE

Non-rigid algorithms improve the quality of abdominal CT perfusion measurements but do not benefit from DECT post processing.

De novo membranous nephropathy in renal allograft associated with antibody-mediated rejection and review of the literature

A 71-year-old woman with unknown renal failure etiology received living donor transplantation had normal graft function for many years. At 11 years from transplantation, she developed nephrotic syndrome. Allograft biopsy showed membranous nephropathy (MN) and C4d positivity in the peritubular capillaries, suggestive of antibody-mediated rejection. At the time of nephrosis onset, she had new donor-specific antibody positivity. The case is unusual in that the diagnosis of de novo MN is based on evidence that she had antibody-mediated rejection. De novo MN remains relatively uncommon; we have reviewed the literature on this diagnosis.

Vacuolar H+-ATPase is down-regulated by the angiogenesis-inhibitory pigment epithelium-derived factor in metastatic prostate cancer cells

The Vacuolar H+-ATPases (V-ATPases), a multi-subunits nanomotor present in all eukaryotic cells resides in the endomembranes of exocytotic and endocytotic pathways. Plasmalemmal V-ATPases have been shown to be involved in tumor cell metastasis. Pigment epithelium-derived factor (PEDF), a potent endogenous inhibitor of angiogenesis, is down-regulated in prostate cancer cells. We hypothesized that the transduction of PEDF in prostate cancer cells will down-regulate V-ATPase function; that in turn will decrease the expression of the V-ATPase accessory protein ATP6ap2 and a-subunit isoforms that target V-ATPase to the cell surface. To test these hypotheses, we used the human androgen-sensitive prostate cancer cells LNCaP, and its castration-refractory-derivative CL1 that were engineered to stably co-express the DsRed Express Fluorescent Protein with or without PEDF. To determine if PEDF down-regulates the function of V-ATPase, we measured the rate of proton fluxes (JH+) of the cytosolic and endosome/lysosome compartments. The mRNA levels for subunit-a isoforms and the ATP6ap2 were measured using quantitative reverse transcription-PCR. The results showed that PEDF expression decreased the rate of JH+ in metastatic CL1 cells without affecting JH+ in non-metastatic LNCaP cells, when studying pH(cyt). Interestingly, PEDF did not affect JH+ in endosomes/lysosomes either in metastatic cells or in non-metastatic cells. We also showed that PEDF significantly decreases the levels of a4 isoform and ATP6ap2 in metastatic CL1 cells, without affecting the levels of a4 isoform in the non-metastatic LNCaP cells. These data identify PEDF as a novel regulator of V-ATPase suggesting a new way by which PEDF may inhibit prostate tumor growth.

Pigment epithelium-derived factor expression prolongs survival and enhances the cytotoxicity of low-dose chemotherapy in castration-refractory prostate cancer

There is currently no cure for advanced castration-refractory prostate cancer (CRPC) despite the recent approval of several new therapeutic agents. We report here the anti-tumor effect of the angio-inhibitory pigment epithelium-derived factor (PEDF) in the metastatic LNCaP-derivative CRPC CL1 model and explore PEDF anti-neoplasic efficacy in combination with low-dose chemotherapy. Androgen-sensitive LNCaP and CRPC PC3 cell lines were examined as comparison. Using a retroviral expression system, we showed that PEDF limited the proliferation of all prostatic cell lines tested; an effect attributed to interleukin 8 (IL8)-CXCR1/IL8RA inhibition. PEDF also reduced the number and size of 3D tumor spheroids in vitro, but only induced cell differentiation in CRPC spheroids. Similarly, PEDF inhibited the migration of CRPC cells suggesting both anti-proliferative and anti-migratory functions. In vivo, PEDF decreased by 85% and 65% the growth of subcutaneous (s.c.) PC3 and CL1 tumors, respectively. In the CL1 orthotopic model, tumor intake with lethal metastases was found in all animals; nevertheless, PEDF prolonged the median survival of tumor-bearing mice (95% confidence interval: 53±0.001 to 57±1 days). Accordingly, PEDF delayed the emergence of skeletal-related event in intra-tibial xenografts. Next, we evaluated low-dose docetaxel (DTX; 5, 1, 0.5 mg/kg) or cyclophosphamide (CTX; 10–20 mg/kg) on established s.c. PC3 tumors that conditionally express PEDF anti-tumoral epitope/NT3. Although NT3–DTX-5 mg/kg combination was inefficient, NT3–DTX-1 mg/kg and -0.5 mg/kg inhibited by 95% and 87.8%, respectively, tumor growth compared with control and induced tumor stasis. Both NT3–CTX combinations were advantageous. Inversely, PEDF–DTX-5 mg/kg and PEDF–CTX-10 mg/kg delayed the most CL1 tumor growth (15, 11 and 5 days for PEDF–DTX-5 mg/kg, PEDF–CTX-10 mg/kg and single treatments, respectively) with elevated apoptosis and serum thrombospondin-1 as possible mechanism and marker, respectively. As well, both PEDF–CTX-10 mg/kg and PEDF–DTX-5 mg/kg prolonged significantly the survival of tumor-bearing mice compared with single treatments. Metastases were reduced in PEDF–DTX-5 mg/kg compared with other treatments, suggesting that PEDF–DTX delayed metastases formation. Our results advocate that PEDF/low-dose chemotherapy may represent a new therapeutic alternative for CRPC.

[Metaanalysis to estimate the expected drop out-rates reported in clinical trials on cataract surgery]

BACKGROUND

A realistic sample size calculation is crucial to achieve significant results in clinical trials. As an expected drop out-rate has to be included in the sample size calculation, current practice consists in the presumption of drop out-rates published in previous similar investigations. This approach may, however, result in severely over- or under-estimated sample sizes. Therefore this meta-analysis sought to aggregate the drop out-rates from published clinical trial reports on cataract surgery to derive a quantitative suggestion for the planning of future clinical trials.

METHODS

The data collection was a complete review of all prospective and retrospective studies in five journals of the years 2002-2012; trial-wise recall rates of subjects at follow-up 3, 6, 12, and 24 months after recruitment were documented. The primary endpoint of the meta-analysis was the reported drop out-rates after 6 months. 95 % confidence intervals were calculated for each trial, respectively; a median drop out-rate was estimated including its 95 % confidence interval. The drop-out-rate estimates were furthermore stratified by design characteristics of the reported studies.

RESULTS

For randomised clinical trials on cataract surgery, the median drop out-rate increased during the follow-up period of 24 months from 4 % at three months to 17 % at 24 months after recruitment; for the six-month drop out-rate a median drop-out rate of 3 % (95 % CI 0 %; 14 %) was estimated.

CONCLUSION

Drop out-rates in sample size calculations for clinical trials on cataract surgery were found to be over-estimated in general, ending up in the calculation of overly large patient numbers and thereby in both ethical and economic consequences. For randomised clinical trials on cataract surgery the median drop out-rate can be expected to be 5 % during a six-month follow-up and may rise up to 15 % during a 12-month trial period.

Inpatient-based intensive interdisciplinary pain treatment for highly impaired children with severe chronic pain: randomized controlled trial of efficacy and economic effects

Pediatric chronic pain, which can result in deleterious effects for the child, bears the risk of aggravation into adulthood. Intensive interdisciplinary pain treatment (IIPT) might be an effective treatment, given the advantage of consulting with multiple professionals on a daily basis. Evidence for the effectiveness of IIPT is scarce. We investigated the efficacy of an IIPT within a randomized controlled trial by comparing an intervention group (IG) (n=52) to a waiting-list control group (WCG) (n=52). We made assessments before treatment (PRE), immediately after treatment (POST), as well as at short-term (POST6MONTHS) and long-term (POST12MONTHS) follow-up. We determined a combined endpoint, improvement (pain intensity, disability, school absence), and investigated 3 additional outcome domains (anxiety, depression, catastrophizing). We also investigated changes in economic parameters (health care use, parental work absenteeism, subjective financial burden) and their relationship to the child's improvement. Results at POST showed that significantly more children in the IG than in the WCG were assigned to improvement (55% compared to 14%; Fisher P<.001; 95% confidence interval for incidence difference: 0.21% to 0.60%). Although immediate effects were achieved for disability, school absence, depression, and catastrophizing, pain intensity and anxiety did not change until short-term follow-up. More than 60% of the children in both groups were improved long-term. The parents reported significant reductions in all economic parameters. The results from the present study support the efficacy of the IIPT. Future research is warranted to investigate differences in treatment response and to understand the changes in economic parameters in nonimproved children.

[Men with type 2 diabetes and erectile dysfunction are a particular risk group for LUTS - results of the Witten Diabetes Survey]

INTRODUCTION

According to our data on 4 071 patients with type 2 diabetes, 65.5% of the men and 70.4% of the women complain of lower urinary tract symptoms (LUTS). That is twice as much as the normal population for the same age group. The most common symptom was overactive bladder (OAB). In patients with a diabetes-related complication such as retinopathy or nephropathy, the incidence for LUTS was about 20% higher than that in patients without complications, whereas in men with diabetes mellitus type 2 and erectile dysfunction (ED) the incidence for LUTS was 31.9% higher than without ED. We wanted to compare the incidence of LUTS in patients with type 2 diabetes and ED against patients without ED as well as women with type 2 diabetes.

RESULTS

Men with ED had a statistically significant longer history of diabetes, a higher HbA1c and increased serum creatinine compared to men without ED (p value <0.0001). The length of diabetes history was not statistically relevant compared to women with type 2 diabetes. However the HbA1c and serum creatinine were higher than those of the women from the data bank (p value <0.0001). Diabetic men with ED complained more often of urinary incontinence, urge incontinence and made more often use of incontinence pads (p value <0.0001). As for pollakisuria and nocturia the difference was not significant. 42.3% of type 2 diabetic patients with ED were diagnosed with OAB by their urologist or GP. That was significantly more than type 2 diabetic patients without ED and type 2 diabetic women (see graph). The same was true of stress incontinence, overflow incontinence and non-classified incontinence with the exception of faecal incontinence. Patients with type 2 diabetes and ED had to take drugs more often than type 2 diabetic men without ED and women with diabetes.

CONCLUSION

Amongst patients with type 2 diabetes, ED increases the risk of developing lower urinary tract disorders. Moreover it is connected with a higher HbA1c and a higher risk for LUTS, especially for OAB. The regular use of incontinence pads in every fourth patient with type 2 diabetes and erectile dysfunction demonstrates a high number of under-treated patients. Patients with type 2 diabetes and especially patients with type 2 diabetes AND erectile dysfunction represent a risk group that needs special attention and a special management plan from urologists and GPs.