Persistent C-peptide is associated with reduced hypoglycaemia but not HbA1c in adults with longstanding Type 1 diabetes: evidence for lack of intensive treatment in UK clinical practice?

AIMS: Most people with Type 1 diabetes have low levels of persistent endogenous insulin production. The Diabetes Control and Complications Trial showed that close to diagnosis preserved endogenous insulin was associated with lower HbA1c , hypoglycaemia and complication rates, when intensively treated. We aimed to assess the clinical impact of persistent C-peptide on rate of hypoglycaemia and HbA1c in those with long duration (> 5 years) Type 1 diabetes. METHODS: We conducted a cross-sectional case-control study of 221 people (median age 24 years) with Type 1 diabetes. We confirmed ongoing endogenous insulin secretion by measuring C-peptide after a mixed-meal tolerance test. We compared self-reported hypoglycaemia (n = 160), HbA1c , insulin dose and microvascular complications (n = 140) in those with preserved and low C-peptide. RESULTS: Stimulated median (IQR) C-peptide was 114 (43, 273) pmol/l and < 3 (< 3, < 3) pmol/l in those with preserved and low C-peptide respectively. Participants with preserved C-peptide had lower reported monthly rates of hypoglycaemia, with 21% fewer symptomatic episodes, 5.9 vs. 7.5 [incidence rate ratio (IRR) 0.79, P = 0.001], and 65% fewer asymptomatic episodes, 1.0 vs. 2.9 (IRR 0.35, P < 0.001). Those with preserved C-peptide had a lower insulin dose (0.68 vs. 0.81 units/kg, P = 0.01) but similar HbA1c (preserved 69 vs. low 67 mmol/mol, P = 0.06). CONCLUSIONS: Adults with Type 1 diabetes and preserved endogenous insulin production receiving usual care in the UK have lower daily insulin doses and fewer self-reported hypoglycaemic episodes, but no difference in HbA1c . This is consistent with non-intensive treatment in previous studies, and suggests a need to consider therapy intensification to gain full benefit of preserved endogenous insulin.

Random non-fasting C-peptide: bringing robust assessment of endogenous insulin secretion to the clinic.

BACKGROUND: Measuring endogenous insulin secretion using C-peptide can assist diabetes management, but standard stimulation tests are impractical for clinical use. Random non-fasting C-peptide assessment would allow testing when a patient is seen in clinic. METHODS: We compared C-peptide at 90 min in the mixed meal tolerance test (sCP) with random non-fasting blood C-peptide (rCP) and random non-fasting urine C-peptide creatinine ratio (rUCPCR) in 41 participants with insulin-treated diabetes [median age 72 (interquartile range 68-78); diabetes duration 21 (14-31) years]. We assessed sensitivity and specificity for previously reported optimal mixed meal test thresholds for severe insulin deficiency (sCP < 200 pmol//l) and Type 1 diabetes/inability to withdraw insulin (< 600 pmol//l), and assessed the impact of concurrent glucose. RESULTS: rCP and sCP levels were similar (median 546 and 487 pmol//l, P = 0.92). rCP was highly correlated with sCP, r = 0.91, P < 0.0001, improving to r = 0.96 when excluding samples with concurrent glucose < 8 mmol//l. An rCP cut-off of 200 pmol//l gave 100% sensitivity and 93% specificity for detecting severe insulin deficiency, with area under the receiver operating characteristic curve of 0.99. rCP < 600 pmol//l gave 87% sensitivity and 83% specificity to detect sCP < 600 pmol//l. Specificity improved to 100% when excluding samples with concurrent glucose < 8 mmol//l. rUCPCR (0.52 nmol/mmol) was also well-correlated with sCP, r = 0.82, P < 0.0001. A rUCPCR cut-off of < 0.2 nmol/ mmol gave sensitivity and specificity of 83% and 93% to detect severe insulin deficiency, with area under the receiver operating characteristic curve of 0.98. CONCLUSIONS: Random non-fasting C-peptide measures are strongly correlated with mixed meal C-peptide, and have high sensitivity and specificity for identifying clinically relevant thresholds. These tests allow assessment of C-peptide at the point patients are seen for clinical care.

Psychiatric morbidity in children with KCNJ11 neonatal diabetes.

AIMS: Mutations in the KCNJ11 gene, which encodes the Kir6.2 subunit of the pancreatic KATP channel, cause neonatal diabetes. KCNJ11 is also expressed in the brain, and ~ 20% of those affected have neurological features, which may include features suggestive of psychiatric disorder. No previous studies have systematically characterized the psychiatric morbidity in people with KCNJ11 neonatal diabetes. We aimed to characterize the types of psychiatric disorders present in children with KCNJ11 mutations, and explore their impact on families. METHODS: The parents and teachers of 10 children with neonatal diabetes due to KCNJ11 mutations completed the Strengths and Difficulties Questionnaire and the Development and Wellbeing Assessment. Strengths and Difficulties Questionnaire scores were compared with normative data. Diagnoses from the Development and Wellbeing Assessment were compared with known clinical diagnoses. RESULTS: Strengths and Difficulties Questionnaire scores indicated high levels of psychopathology and impact. Psychiatric disorder(s) were present in all six children with the V59M or R201C mutation, and the presence of more than one psychiatric disorder was common. Only two children had received a formal clinical diagnosis, with a further one awaiting assessment, and the coexistence of more than one psychiatric disorder had been missed. Neurodevelopmental (attention deficit hyperactivity disorder and autism) and anxiety disorders predominated. CONCLUSIONS: Systematic assessment using standardized validated questionnaires reveals a range of psychiatric morbidity in children with KCNJ11 neonatal diabetes. This is under-recognized clinically and has a significant impact on affected children and their families. An integrated collaborative approach to clinical care is needed to manage the complex needs of people with KCNJ11 neonatal diabetes.

Tumor diameter accurately predicts perioperative outcomes in T1 renal cancer treated with robot-assisted partial nephrectomy.

PURPOSE: To compare diameter as a continuous variable with categorical R.E.N.A.L. nephrometry score (RNS) in predicting surgical outcomes of robotic partial nephrectomy (RPN). METHODS: We retrospectively reviewed consecutive patients receiving RPN at our institution between July 2007 and June 2014 (n = 286). Three separate multivariate analyses were performed to assess the relationship between RNS components (R = radius, E = endophyticity, N = nearness to collecting system, L = location relative to polar lines), total RNS, and diameter as a continuous variable with operating time, warm ischemia time (WIT), and estimated blood loss (EBL). Each linear regression model's quality of fit to the data was assessed with coefficients of determination (R 2). RESULTS: Continuous tumor diameter and total RNS were each significantly correlated to operative time, EBL, and WIT (p < 0.001). Categorical R related to operative time (R = 2 vs. R = 1, p = 0.001; R = 3 vs. R = 1, p = 0.001) and WIT (R = 2 vs. R = 1, p = 0.003; R = 3 vs. R = 1, p = 0.016), but not to EBL. For each of these outcomes, diameter outperformed both R and total RNS, as assessed by R 2. Age, body mass index, Charlson Comorbidity Index, and anterior versus posterior location did not correlate with surgical outcomes. CONCLUSIONS: In this series of RPN from a high-volume center, surgical outcomes more closely related to tumor diameter than RNS. While RNS provides surgeons a standardized tool for preoperative planning of renal masses, tumor size may be employed as a more familiar measurement when counseling patients on potential outcomes.

Early predictive biomarkers for postpartum depression point to a role for estrogen receptor signaling.

BACKGROUND: Postpartum depression (PPD) affects approximately 13% of women and has a negative impact on mother and infant, hence reliable biological tests for early detection of PPD are essential. We aimed to identify robust predictive biomarkers for PPD using peripheral blood gene expression profiles in a hypothesis-free genome-wide study in a high-risk, longitudinal cohort. METHOD: We performed a genome-wide association study in a longitudinal discovery cohort comprising 62 women with psychopathology. Gene expression and hormones were measured in the first and third pregnancy trimesters and early postpartum (201 samples). The replication cohort comprised 24 women with third pregnancy trimester gene expression measures. Gene expression was measured on Illumina-Human HT12 v4 microarrays. Plasma estradiol and estriol were measured. Statistical analysis was performed in R. RESULTS: We identified 116 transcripts differentially expressed between the PPD and euthymic women during the third trimester that allowed prediction of PPD with an accuracy of 88% in both discovery and replication cohorts. Within these transcripts, significant enrichment of transcripts implicated that estrogen signaling was observed and such enrichment was also evident when analysing published gene expression data predicting PPD from a non-risk cohort. While plasma estrogen levels were not different across groups, women with PPD displayed an increased sensitivity to estrogen signaling, confirming the previously proposed hypothesis of increased sex-steroid sensitivity as a susceptibility factor for PPD. CONCLUSIONS: These results suggest that PPD can be robustly predicted in currently euthymic women as early as the third trimester and these findings have implications for predictive testing of high-risk women and prevention and treatment for PPD.

Urinary C-peptide creatinine ratio detects absolute insulin deficiency in Type 2 diabetes.

AIMS: To determine the prevalence and clinical characteristics of absolute insulin deficiency in long-standing Type 2 diabetes, using a strategy based on home urinary C-peptide creatinine ratio measurement. METHODS: We assessed the urinary C-peptide creatinine ratios, from urine samples taken at home 2 h after the largest meal of the day, in 191 insulin-treated subjects with Type 2 diabetes (diagnosis age ≥45 years, no insulin in the first year). If the initial urinary C-peptide creatinine ratio was ≤0.2 nmol/mmol (representing absolute insulin deficiency), the assessment was repeated. A standardized mixed-meal tolerance test with 90-min stimulated serum C-peptide measurement was performed in nine subjects with a urinary C-peptide creatinine ratio ≤ 0.2 nmol/mmol (and in nine controls with a urinary C-peptide creatinine ratio >0.2 nmol/mmol) to confirm absolute insulin deficiency. RESULTS: A total of 2.7% of participants had absolute insulin deficiency confirmed by a mixed-meal tolerance test. They were identified initially using urinary C-peptide creatinine ratio: 11/191 subjects (5.8%) had two consistent urinary C-peptide creatinine ratios ≤ 0.2 nmol/mmol; 9 of these 11 subjects completed a mixed-meal tolerance test and had a median stimulated serum C-peptide of 0.18 nmol/l. Five of these 9 had stimulated serum C-peptide <0.2 nmol/l and 9/9 subjects with urinary C-peptide creatinine ratio >0.2 had endogenous insulin secretion confirmed by the mixed-meal tolerance test. Compared with subjects with a urinary C-peptide creatinine ratio >0.2 nmol/mmol, those with confirmed absolute insulin deficiency had a shorter time to insulin treatment (median 2.5 vs. 6 years, P=0.005) and lower BMI (25.1 vs. 29.1 kg/m(2) , P=0.04). Two out of the five patients with absolute insulin deficiency were glutamic acid decarboxylase autoantibody-positive. CONCLUSIONS: Absolute insulin deficiency may occur in long-standing Type 2 diabetes, and cannot be reliably predicted by clinical features or autoantibodies. Absolute insulin deficiency in Type 2 diabetes may increase the risk of hypoglycaemia and ketoacidosis, as in Type 1 diabetes. Its recognition should help guide treatment, education and management. The urinary C-peptide creatinine ratio is a practical non-invasive method to aid detection of absolute insulin deficiency, with a urinary C-peptide creatinine ratio > 0.2 nmol/mmol being a reliable indicator of retained endogenous insulin secretion.

Tumor markers in metastatic breast cancer subtypes: frequency of elevation and correlation with outcome.

BACKGROUND: Little is known about the correlations between tumor markers (TMs), breast cancer subtypes, site(s) of metastasis and prognosis. METHODS: Women diagnosed with metastatic breast cancer were included. Breast cancer subtypes were defined as LuminalA, LuminalB, LuminalHer2, Her2, Basal and non-Basal triple negative (TN). Levels of elevation of TM values [cancer antigen 15-3 (CA 15-3), carcinoembryonic antigen (CEA) and cancer antigen 125 (CA 125)] among the subtypes were analyzed. Site(s) of metastasis and outcomes were captured. RESULTS: Eight hundred and ten patients were included. Luminal subtypes were associated with an elevation in at least one TM: 90.8% of LuminalHer2+, 90% of LuminalB and 88.6% of LuminalA. TMs were less frequently elevated in Basal (74.1%) and non-Basal TN (71.4%) cases (P < 0.001). CA 15-3 was the most frequently elevated TM. The incidence of TM elevation did not differ between patients with solitary versus multiple metastatic sites. Breast cancer-specific survival (BCSS) was significantly worse for patients with elevated TMs (P = 0.001). CONCLUSIONS: TM elevation of CA 15-3, CEA and/or CA 125 was documented in the majority of patients with metastatic breast cancer with CA 15-3 occurring most commonly. Luminal subtypes expressed elevated TMs significantly more frequently compared with the non-Luminal groups. TM elevation was not different between the different sites of metastasis. Overall, elevated TMs predicted a worse BCSS.

Validation of a single-sample urinary C-peptide creatinine ratio as a reproducible alternative to serum C-peptide in patients with Type 2 diabetes.

AIMS: Serum C-peptide can be used in Type 2 diabetes as a measure of endogenous insulin secretion, but practicalities of collection limit its routine clinical use. Urine C-peptide creatinine ratio is a non-invasive alternative that is stable for at least 3 days at room temperature in boric acid preservative. We aimed to assess the utility of urine C-peptide creatinine ratio in individuals with Type 2 diabetes as an alternative to serum C-peptide. METHODS: We assessed, in 77 individuals with Type 2 diabetes, the reproducibility of, and correlations between, fasting and postprandial urine C-peptide creatinine ratio and serum C-peptide, and the impact of renal impairment (estimated glomerular filtration rate < 60 ml min(-1) 1.73 m(-2)) on these correlations. RESULTS: Urine C-peptide creatinine ratio was at least as reproducible as serum C-peptide [fasting coefficient of variation mean (95% CI): 28 (21-35)% vs. 38 (26-59)% and 2-h post-meal 26 (18-33)% vs. 27 (20-34)%. Urine C-peptide creatinine ratio 2 h post-meal was correlated with stimulated serum C-peptide, both the 2-h value (r = 0.64, P < 0.001) and the 2-h area under the C-peptide curve (r = 0.63, P < 0.001). The association seen was similar in patients with and without moderate renal impairment (P = 0.6). CONCLUSIONS: In patients with Type 2 diabetes, a single urine C-peptide creatinine ratio is a stable, reproducible measure that is well correlated with serum C-peptide following meal stimulation, even if there is moderate renal impairment. Urine C-peptide creatinine ratio therefore has potential for use in clinical practice in the assessment of Type 2 diabetes.

The impact of insulin administration during the mixed meal tolerance test.

AIMS: The mixed meal tolerance test is the gold standard measure of endogenous insulin secretion. Practical issues limit the routine clinical use of this test, including omitting insulin prior to the ingestion of a high-carbohydrate liquid mixed meal, which can result in marked hyperglycaemia. We aimed to assess whether insulin omission is necessary during the mixed meal tolerance test and whether fasting C-peptide was a practical alternative to the test. METHODS: Ninety-one adults with insulin-treated diabetes (Type 1 n = 56, Type 2 n = 35) underwent two mixed meal tolerance tests; one standard without insulin and one with the patient's usual morning insulin. RESULTS: The 90-min serum C-peptide was highly correlated in the standard mixed meal tolerance test and the test with insulin (r = 0.98, P < 0.0001). There was a 20% reduction in the peak C-peptide value when insulin was given {test with insulin [0.39 (0.01-1.16) vs. test without insulin 0.48 (0.01-1.36) nmol/l, P = 0.001]}, but the original serum C-peptide cut-off for significant endogenous insulin secretion (≥ 0.2 nmol/l) still correctly classified 90/91 patients (98% sensitivity/100% specificity). Fasting serum C-peptide was highly correlated to 90-min serum C-peptide during the test (r = 0.97, P < 0.0001). A fasting serum C-peptide ≥ 0.07 nmol/l was the optimal cut-off (100% sensitivity and 97% specificity) for significant endogenous insulin secretion (defined as 90-min stimulated serum C-peptide ≥ 0.2 nmol/l). CONCLUSIONS: Insulin omission may not always be necessary during a mixed meal tolerance test and fasting serum C-peptide may offer a practical alternative in insulin-treated patients.

Outcomes of emergency laparoscopy in the elderly.

INTRODUCTION: This paper assessed the association between operative approach and postoperative in-hospital mortality in elderly patients undergoing emergency abdominal surgery. Patients undergoing emergency laparotomy have high morbidity and mortality rates. One-third of patients requiring emergency surgery are over 75 years old, and their in-hospital mortality rate exceeds 17%. Fewer than 20% of emergency abdominal operations in the UK are attempted laparoscopically, and only 10% are completed laparoscopically. Little is known about how laparoscopic emergency surgery in the elderly might affect outcomes. METHODS: An observational UK study was performed using the prospectively maintained National Emergency Laparotomy Audit (NELA) database. Operative approach, NELA risk-prediction score and in-hospital mortality were recorded. The effect of operative approach on in-hospital mortality was analysed, both on a national basis and in a high-volume laparoscopic centre. RESULTS: A total of 47,667 patients were included in the study, of whom 15,068 were over 75 years of age. Nationally, surgery was completed by the laparoscopic approach in 7.8% of patients aged over 75; both crude mortality (9.2%) and risk-adjusted mortality (7.1%) were significantly reduced (p<0.0001). In our unit, surgery was completed laparoscopically in 48.4% of patients aged over 75; both crude mortality (6.6%) and risk-adjusted mortality (3.3%) were significantly reduced (p<0.0001). CONCLUSION: Laparoscopy in emergency surgery has been shown in this study to significantly reduce in-hospital mortality in elderly patients and should be embraced in every centre dealing with emergency abdominal surgery.

Urine C-peptide creatinine ratio is an alternative to stimulated serum C-peptide measurement in late-onset, insulin-treated diabetes.

AIMS: Serum C-peptide measurement can assist clinical management of diabetes, but practicalities of collection limit widespread use. Urine C-peptide creatinine ratio may be a non-invasive practical alternative. The stability of C-peptide in urine allows outpatient or community testing. We aimed to assess how urine C-peptide creatinine ratio compared with serum C-peptide measurement during a mixed-meal tolerance test in individuals with late-onset, insulin-treated diabetes. METHODS: We correlated the gold standard of a stimulated serum C-peptide in a mixed-meal tolerance test with fasting and stimulated (mixed-meal tolerance test, standard home meal and largest home meal) urine C-peptide creatinine ratio in 51 subjects with insulin-treated diabetes (diagnosis after age 30 years, median age 66 years, median age at diagnosis 54, 42 with Type 2 diabetes, estimated glomerular filtration rate > 60 ml min(-1) 1.73 m(-2) ). RESULTS: Ninety-minute mixed-meal tolerance test serum C-peptide is correlated with mixed-meal tolerance test-stimulated urine C-peptide creatinine ratio (r = 0.82), urine C-peptide creatinine ratio after a standard breakfast at home (r = 0.73) and urine C-peptide creatinine ratio after largest home meal (r = 0.71). A stimulated (largest home meal) urine C-peptide creatinine ratio cut-off of 0.3 nmol/mmol had a 100% sensitivity and 96% specificity (area under receiver operating characteristic curve = 0.99) in identifying subjects without clinically significant endogenous insulin secretion (mixed-meal tolerance test-stimulated C-peptide < 0.2 nmol/l). In detecting a proposed serum C-peptide threshold for insulin requirement (stimulated serum C-peptide < 0.6 nmol/l), a stimulated (largest home meal) urine C-peptide creatinine ratio cut-off of 0.6 nmol/mmol had a sensitivity and specificity of 92%. CONCLUSION: In patients with insulin-treated diabetes diagnosed after age 30 years, urine C-peptide creatinine ratio is well correlated with serum C-peptide and may provide a practical alternative measure to detect insulin deficiency for use in routine clinical practice.

Clinical frailty and its effect on the septuagenarian population after emergency laparotomy.

INTRODUCTION: The UK has an ageing population with an increased prevalence of frailty in the over 70s. Emergency laparotomy for acute intra-abdominal pathology is increasingly offered to this population. This can challenge decision making and information given to patients should not only be based on mortality outcomes but on relative expected quality of life and change to frailty syndromes. MATERIALS AND METHODS: This was a single site National Emergency Laparotomy Audit (NELA)-based retrospective cohort audit for consecutive cases in the septuagenarian population assessing mortality, length of stay outcome and subjective postoperative functioning. Follow-up was conducted between one and two years postoperatively to determine this. RESULTS: Some 153 patients were identified throughout the single site NELA database. Median age was 79 years with a ratio of 1.7 men to women. Median rate of all-cause mortality was 35.3% at the median follow-up of 19 months. Median time from admission to death was 120 days. Of those who had died by the time of follow-up, significant preoperative indicators included clinical frailty scale (p < 0.0001), preoperative P-POSSUM (mortality). At follow-up, 35% responded to a quality of life follow-up. This revealed a decline in mid-term physical functioning, lower energy, higher fatigue and reduction in social functioning. There was also an increase in pre- and postoperative clinical frailty scale score. CONCLUSION: In the septuagenarian-plus population it is important to consider not only risk stratification with mortality scoring (P-POSSUM or NELA-adjusted risk), but to take into account frailty. Postoperative rehabilitation and careful recovery is paramount. Where possible, during the counselling and consent for emergency laparotomy, significant postoperative long-term deterioration in physical, emotional and social function should be considered.

Geographic disparities in performance of pediatric polysomnography to diagnose obstructive sleep apnea in a universal access health care system.

BACKGROUND: Diagnostic polysomnography (PSG) is recommended prior to adenotonsillectomy (AT) for children with obstructive sleep apnea (OSA) and certain high-risk characteristics, but resource limitations often prevent this practice. OBJECTIVE: We performed a population-based assessment of children across Ontario, Canada to describe and quantify disparities in PSG. METHODS AND MATERIALS: This retrospective cohort study was performed using provincial health administrative data held at ICES. We identified children 0-10 years old who underwent PSG and AT between 2009 and 2018, and those with a PSG within 18 months prior to and/or 12 months following AT. We calculated the odds of PSG prior to/following AT after adjustment for demographics, medical comorbidities, geographic and socioeconomic characteristics. Our main predictor was driving time/distance to the nearest pediatric sleep centre ascertained using spatial analysis and geographic information systems. RESULTS: We identified 27,837 children <10 years old who underwent AT for OSA in Ontario. Only 12.8% had a PSG within 18 months prior and 5.7% had a PSG within 12 months following AT. Shorter driving time/distance, older age, male sex and certain comorbidities were associated with increased odds of PSG. CONCLUSION: Only a small proportion of children in our cohort underwent PSG prior to or following AT surgery despite universal access to healthcare. This study suggests a need to increase overall PSG access, particularly for those living distant from existing pediatric sleep centres. Future studies could determine if increased PSG testing in 'underserviced areas' would reduce overall surgery rates and/or improve health outcomes.

Clinical outcomes after increasing bladder outlet resistance without augmentation cystoplasty in neurogenic bladder.

INTRODUCTION: Patients with neurogenic bladder (NGB) and urinary incontinence (UI) due to low bladder outlet resistance may require bladder neck procedures (BNPs) to achieve continence. These patients may also have reduced bladder capacity and or elevated detrusor storage pressures that require augmentation cystoplasty (AC). AC is not without complications that include risks for bladder rupture, urolithiasis, urinary tract infections and metabolic issues. Avoidance of AC would be helpful in patients with neurogenic urinary incontinence that have safe bladder parameters in the setting of low bladder outlet resistance. OBJECTIVE: To determine if pre-operative urodynamics could select children with NGBs and UI for isolated BNPs without AC. Additionally we sought to determine the safety of BNPs without AC and future need of AC with long-term follow-up. STUDY DESIGN: This is an IRB-approved retrospective analysis of all patients undergoing BNPs for management of neurogenic UI over a 17-year period. We separated these BNP patients into two groups: No AC + BNP (Group 1) vs. AC + BNP (Group 2). Our primary analyses focused on postoperative outcomes for patients in Group 1. Outcomes assessed included additional surgical procedures, urodynamic changes, development of CKD, new hydronephrosis (HDN) and vesicoureteral reflux (VUR). Secondary analysis included the timeline for the development of any bladder deterioration that necessitated AC in Group 1. RESULTS: 93 patients underwent BNP at a mean age of 10.8 years. Thirty did not have AC at the time of surgery (Group 1). These children had larger (p < 0.001) and more compliant (p < 0.001) bladders than Group 2 having simultaneous augmentation. At 6 years mean follow-up in Group 1 patients, three developed new reflux and three had new hydronephrosis. Nine (30%) had additional continence procedures. Twelve required (40%) AC at a mean of 23 months after the initial BNP. No patients had AC after 5 years. Detrusor end filling pressure increased 14.8 cm H2O (p = 0.028) and expected bladder capacity decreased 26.1% (p = 0.005) after isolated BNP. DISCUSSION: We found that from our cohort of patients who had normal bladder compliance and normal/near normal expected capacity preoperatively 40% required subsequent AC. We were unable to find pre-operative clinical parameters which predicted failure or conversion to AC. We found that 43.3% of our BNP without AC patients had no subsequent invasive procedures with mean 6-year follow-up. We found that none of our patients developed any degree of CKD. Finally, we found that the majority of patients that converted to AC after their BNP did so within the first 2 years after their initial BNP and no patients required augmentation 5 years post their initial BNP. This data validates that these patients require very strict follow up, particularly in the first 5 years after surgery. CONCLUSIONS: BNP without AC is safe in only a few selected patients with NGB. Despite preoperative selection, there are significant changes in bladder dynamics and 40% required subsequent augmentation. Bladder deterioration occurs early and generally in the first 2 years. Since there are no apparent reliable pre-operative variables predicting the need for subsequent AC, parents should be counseled regarding vigilant post-operative follow-up.

Impaired preneoplastic changes and liver tumor formation in tumor necrosis factor receptor type 1 knockout mice.

Hepatic stem cells (oval cells) proliferate within the liver after exposure to a variety of hepatic carcinogens and can generate both hepatocytes and bile duct cells. Oval cell proliferation is commonly seen in the preneoplastic stages of liver carcinogenesis, often accompanied by an inflammatory response. Tumor necrosis factor (TNF), an inflammatory cytokine, is also important in liver regeneration and hepatocellular growth. The experiments reported here explore the relationship among the TNF inflammatory pathway, liver stem cell activation, and tumorigenesis. We demonstrate that TNF is upregulated during oval cell proliferation induced by a choline-deficient, ethionine-supplemented diet and that it is expressed by oval cells. In TNF receptor type 1 knockout mice, oval cell proliferation is substantially impaired and tumorigenesis is reduced. Oval cell proliferation is impaired to a lesser extent in interleukin 6 knockout mice and is unchanged in TNF receptor type 2 knockout mice. These findings demonstrate that TNF signaling participates in the proliferation of oval cells during the preneoplastic phase of liver carcinogenesis and that loss of signaling through the TNF receptor type 1 reduces the incidence of tumor formation. The TNF inflammatory pathway may be a target for therapeutic intervention during the early stages of liver carcinogenesis.

Evaluation of surgical outcome scores according to ISGPS definitions in patients undergoing pancreatic resection.

AIMS: To evaluate the role of the Physiological and Operative Severity Score for the enUmeration of Mortality and Morbidity (POSSUM), the Portsmouth variant (p-POSSUM) and the Glasgow Prognostic Score (GPS) in predicting outcome after pancreatic surgery with reference to the International Study Group of Pancreatic Surgery (ISGPS) definitions of post-pancreatectomy complications. METHODS: All consecutive patients undergoing major pancreatic resection over a 32- month period were included. POSSUM, p-POSSUM and GPS score were calculated for each patient and correlated against the observed mortality and morbidity using the ISGPS definitions. RESULTS: The observed:expected ratios for POSSUM mortality, POSSUM morbidity and p-POSSUM mortality were 0.24 (p < 0.0001), 0.86 (p < 0.0001) and 0.79 (p = 0.09), respectively. POSSUM had a 'poor fit' with respect to predicting morbidity (χ(2) = 16.4, 8 d.f., p = 0.04). Multifactorial regression analysis revealed the GPS as an independent predictor of post-operative outcome (GPS 1, p = 0.03, OR 2.99, 95% CI 1.4-7.9, and GPS 2, p = 0.02, OR 4.3, 95% CI 1.8-15.5). CONCLUSION: POSSUM has a limited role as an outcome score in pancreatic resection. The GPS may be a novel alternative to POSSUM as a pre-operative predictor of outcome.

Postoperative management factors affect urinary retention following posterior spinal fusion for adolescent idiopathic scoliosis.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: This study investigates postoperative urinary retention (POUR) following posterior spinal fusion (PSF) for adolescent idiopathic scoliosis (AIS) and the effects of postoperative analgesia and mobility on retention. High opioid use and decreased postoperative mobility are proposed risk factors for retention in adults. There is a paucity of literature on POUR in the adolescent population undergoing surgery for AIS. The impact of pain control and mobility on POUR in these patients is unknown. METHODS: A retrospective cohort study was conducted of adolescents (11-18 years) undergoing elective PSF for AIS at a single institution (2012-2018). POUR was defined as the inability to void > 8 h after catheter removal. Possible risk factors for retention including opioid usage and ambulatory status at the time of catheter removal were assessed on univariate and binomial logistic regression analyses. RESULTS: One hundred and thirty-six patients were included, with 21 (15.4%) experiencing POUR. On the day of catheter removal, 24 patients had not attempted ambulation; these patients had 2.5 times higher rate of POUR than those who were walking (30% vs. 12%, p = 0.04). Patients who developed retention ambulated a mean threefold shorter distance than those without POUR (45 vs. 136 feet, p = 0.04). On binomial logistic regression, decreased ambulation distance was associated with retention (p = 0.038). While opioid use was not significant on univariate analysis, higher opioid use on the day of catheter removal predicted retention on logistic regression (p = 0.001). POUR resolved in all patients (median duration 0.5 days, range 0-12 days). CONCLUSIONS: The development of POUR after PSF for AIS affects one in six patients but resolves quickly. Non-ambulatory patients and patients who received large doses of opioids on the day of catheter removal were more likely to develop POUR. LEVEL OF EVIDENCE: III.

Intrathecal drug delivery in the era of nanomedicine.

Administration of substances directly into the cerebrospinal fluid (CSF) that surrounds the brain and spinal cord is one approach that can circumvent the blood-brain barrier to enable drug delivery to the central nervous system (CNS). However, molecules that have been administered by intrathecal injection, which includes intraventricular, intracisternal, or lumbar locations, encounter new barriers within the subarachnoid space. These barriers include relatively high rates of turnover as CSF clears and potentially inadequate delivery to tissue or cellular targets. Nanomedicine could offer a solution. In contrast to the fate of freely administered drugs, nanomedicine systems can navigate the subarachnoid space to sustain delivery of therapeutic molecules, genes, and imaging agents within the CNS. Some evidence suggests that certain nanomedicine agents can reach the parenchyma following intrathecal administration. Here, we will address the preclinical and clinical use of intrathecal nanomedicine, including nanoparticles, microparticles, dendrimers, micelles, liposomes, polyplexes, and other colloidalal materials that function to alter the distribution of molecules in tissue. Our review forms a foundational understanding of drug delivery to the CSF that can be built upon to better engineer nanomedicine for intrathecal treatment of disease.