Perfusion pressure flow study in the upper urinary tract

Hydronephrosis with an undetermined pathology is a common condition detected in imaging studies. In urological clinical practice, it is a persistent dilemma to predict whether this condition will progress to result in the deterioration of renal function. Perfusion pressure flow study of the upper urinary tract, known as the Whitaker test, provides an alternative diagnostic tool for solving this condition. Perfusion pressure flow study has been criticized for its invasiveness, nonphysiological approach, and inconsistency in predicting outcomes. However, it continues to be used to evaluate difficult or equivocal cases and to provide an objective assessment of the upper urinary tract.     

Dynamic LVOT Obstruction and Aortic Stenosis in the Same Patient: A Case of Challenging Doppler Hemodynamics

We present a patient with both dynamic left ventricular outflow tract obstruction and valvular aortic stenosis. The aortic valve was calcified, and velocities and gradients measured by continuous‐wave Doppler met standard criteria for severe aortic stenosis. The increased subvalvular velocities invalidated assumptions of the simplified Bernoulli equation; correction using the longer form of the Bernoulli equation suggested a lower but still significant gradient. The complex shape of the subvalvular spectral Doppler envelope indicated supranormal systolic function and dynamic left ventricular outflow obstruction. Left heart catheterization with an end‐hole catheter was required to determine the subvalvular and valvular components of the obstruction.     

Intervention for arch obstruction after the Norwood procedure: Prevalence,associated factors,and practice variability

Objective

Arch obstruction after the Norwood procedure is common and contributes to mortality. We determined the prevalence, associated factors, and practice variability of arch reintervention and assessed whether arch reintervention is associated with mortality.

Development of an IgG-Fc fusion COVID-19 subunit vaccine,AKS-452

AKS-452 is a biologically-engineered vaccine comprising an Fc fusion protein of the SARS-CoV-2 viral spike protein receptor binding domain antigen (Ag) and human IgG1 Fc (SP/RBD-Fc) in clinical development for the induction and augmentation of neutralizing IgG titers against SARS-CoV-2 viral infection to address the COVID-19 pandemic. The Fc moiety is designed to enhance immunogenicity by increasing uptake via Fc-receptors (FcγR) on Ag-presenting cells (APCs) and prolonging exposure due to neonatal Fc receptor (FcRn) recycling. AKS-452 induced approximately 20-fold greater neutralizing IgG titers in mice relative to those induced by SP/RBD without the Fc moiety and induced comparable long-term neutralizing titers with a single dose vs. two doses. To further enhance immunogenicity, AKS-452 was evaluated in formulations containing a panel of adjuvants in which the water-in-oil adjuvant, Montanide™ ISA 720, enhanced neutralizing IgG titers by approximately 7-fold after one and two doses in mice, including the neutralization of live SARS-CoV-2 virus infection of VERO-E6 cells. Furthermore, ISA 720-adjuvanted AKS-452 was immunogenic in rabbits and non-human primates (NHPs) and protected from infection and clinical symptoms with live SARS-CoV-2 virus in NHPs (USA-WA1/2020 viral strain) and the K18 human ACE2-trangenic (K18-huACE2-Tg) mouse (South African B.1.351 viral variant). These preclinical studies support the initiation of Phase I clinical studies with adjuvanted AKS-452 with the expectation that this room-temperature stable, Fc-fusion subunit vaccine can be rapidly and inexpensively manufactured to provide billions of doses per year especially in regions where the cold-chain is difficult to maintain.     

Cardiac-type total anomalous pulmonary venous return is not benign

ObjectiveThe objective of this study was to investigate the association between morphological variation and postsurgical pulmonary vein (PV) stenosis (PPVS) in patients with cardiac total anomalous pulmonary venous connection (TAPVC).MethodsThis single-center, retrospective study included 168 pediatric patients who underwent surgical repair of cardiac TAPVC from 2013 to 2019 (connection to the coronary sinus [CS], n = 136; connection directly to the right atrium [RA], n = 32). Three-dimensional computed tomography modeling and geometric analysis were performed to investigate the morphological features; their relevance to the PPVS was examined.ResultsThe connection type had no association with PPVS (CS type: 18% vs right atrial type: 19%; P = .89) but there was a higher incidence of PPVS in patients with a single PV orifice than > 1 orifice (P < .001). Confluence-to-total PV area ratio (hazard ratio, 4.78, 95% CI, 1.86-12.32; P = .001) and length of drainage route (hazard ratio, 1.22; 95% CI, 1.14-1.31; P < .001) had a 4- and 1-fold increase in the risk for PPVS in the CS type after adjustment for age and preoperative pulmonary venous obstruction. In the right atrial type, those with anomalous PV return to the RA roof were more likely to develop PPVS than to the posterior wall of the RA (P < .001).ConclusionsThe number of inter-junction PV orifice correlated with PPVS development in cardiac TAPVC. The confluence-to-total PV ratio, length of drainage route, and anomalous PV return to the RA roof are important predictors for PPVS. Morphological subcategorization in this clinical setting can potentially assist in surgical decision-making.     

Risk factors and management of stoma-related obstruction after laparoscopic colorectal surgery with diverting ileostomy

BackgroundStoma-related obstruction (SRO) is defined as small bowel obstruction occurring around the limbs of diverting ileostomy (DI). This study was aimed to investigate the incidence, risk factors, and management of SRO after laparoscopic colorectal surgery with DI creation.MethodsThis study included 155 patients who underwent laparoscopic colorectal surgery with DI creation for rectal cancer (n = 138), ulcerative colitis (UC) (n = 14), and familial adenomatous polyposis (FAP) (n = 3) between 2011 and 2019. Univariate and multivariate analyses were performed to identify the risk factors of SRO.ResultsThe incidence of SRO was 7.7% (n = 12), and it was significantly lower (P < 0.01) in patients with lower anterior resection or intersphincteric resection (4.3%) than in those with ileal-pouch anal anastomosis (IPAA) (35.2%). The multivariate analysis revealed that IPAA was independently associated with the development of SRO (P = 0.001; odds ratio, 9.4; 95% confidence interval, 2.5–35.4). Eleven of 12 patients (92%) with SRO required trans-stomal tube decompression, and 8 of those (67%) underwent early stoma closure.ConclusionIPAA was an independent risk factor of SRO in laparoscopic colorectal surgery with DI creation. Early stoma closure was needed in most cases of SRO.     

The practical assessment and management of bladder outflow obstruction

The initial management of bladder outflow obstruction typically related to benign prostatic hyperplasia (BPH) falls to a large extent within the remit of general practice. Referral onwards to secondary care typically arises following the failure to respond to conservative measures or when complications have supervened; the most significant of which is urinary retention. In the hospital setting, anaesthesia, constipation and immobility are the common precipitants. What follows is a practical guide to the management of these situations and provides an overview of the conservative, medical, minimally invasive and surgical treatments available.     

Prenatal Sonography in Suspected Proximal Gastrointestinal Obstructions: Diagnostic Accuracy and Neonatal Outcomes

BackgroundThe purpose of this study was to assess diagnostic accuracy and neonatal outcomes in fetuses with a suspected proximal gastrointestinal obstruction (GIO).MethodsAfter IRB approval, a retrospective chart review was conducted on prenatally suspected and/or postnatally confirmed cases of proximal GIO at a tertiary care facility (2012–2022). Maternal-fetal records were queried for presence of a double bubble ± polyhydramnios, and neonatal outcomes were assessed to calculate the diagnostic accuracy of fetal sonography.ResultsAmong 56 confirmed cases, the median birthweight and gestational age at birth were 2550 g [interquartile range (IQR) 2028–3012] and 37 weeks (IQR 34–38), respectively. There was one (2%) false-positive and three (6%) false-negatives by ultrasound. Double bubble had a sensitivity, specificity, positive predictive value, and negative predictive value for proximal GIO of 85%, 98%, 98%, and 83%, respectively. Pathologies included 49 (88%) with duodenal obstruction/annular pancreas, three (5%) with malrotation, and three (5%) with jejunal atresia. The median postoperative length of stay was 27 days (IQR 19–42). Cardiac anomalies were associated with significantly higher complications (45% vs 17%, p = 0.030).ConclusionsIn this contemporary series, fetal sonography has high diagnostic accuracy for detecting proximal gastrointestinal obstruction. These data are informative for pediatric surgeons in prenatal counseling and preoperative discussions with families.Level of EvidenceDiagnostic Study, Level III.