Isolated Hydronephrosis and Urinary Tract Infection by Two Years of Age: A Population-Based Study

OBJECTIVE

To evaluate the risk for urinary tract infection (UTI) in infants with isolated hydronephrosis (IH).

STUDY DESIGN

A retrospective, population-based study including all infants insured by Clalit Health Services (CHS) and followed from birth to age 2 years in 3 regions of central Israel. Infants were divided into 3 groups based on electronic medical record (EMR) diagnoses by age 6 months: 1) control - no urological diagnosis; 2) IH; and 3) "complicated urological diagnosis" (CUD): any additional nephrological/urological diagnosis with/without HN. The primary outcome was a diagnosis of UTI in the first two years of life.

RESULTS

The cohort included 340,619 infants (52% male): 333,920 controls group, 4,369 with IH, and 2,331 with CUD. IH was associated with a higher risk for UTI compared with controls (17% vs. 4%, p<0.001). UTI risk for a male with IH was higher than for a female in the control group (12.6% vs 6.5%, p< 0.001). In a multivariable logistic regression analysis, both IH (OR 7.04, 95% CI: 6.46-7.66) and CUD (OR 14.9, 95% CI: 13.6-16.4) were independently associated with UTI.

CONCLUSION

Infants with IH are at a higher risk for UTI in the first 2 years of life, supporting the recommendation for a high index of suspicion for UTI in this population.

A Nuphar lutea plant active ingredient, 6,6'-dihydroxythiobinupharidine, ameliorates kidney damage and inflammation in a mouse model of chronic kidney disease

Chronic Kidney Disease (CKD) associated complications are associated with increased inflammation through the innate immune response, which can be modulated with anti-inflammatory agents. An active ingredient derived from the Nuphar lutea aquatic plant, 6,6'-dihydroxythiobinupharidine (DTBN) has anti-inflammatory properties, mainly through the inhibition of NF-κB. We tested the effects of DTBN on mice with CKD. After preliminary safety and dosing experiments, we exposed 8 weeks old male C57BL/6J mice to adenine diet to induce CKD. Control and CKD animals were treated with IP injections of DTBN (25 μg QOD) or saline and sacrificed after 8 weeks. Serum urea and creatinine were significantly decreased in CKD-DTBN Vs CKD mice. Kidney histology showed a decrease in F4/80 positive macrophage infiltration, damaged renal area, as well as decreased kidney TGF-β in CKD-DTBN Vs CKD mice. Kidney inflammation indices (IL-1β, IL-6 and P-STAT3) were significantly decreased in CKD-DTBN as compared to CKD mice. DTBN treatment showed no apparent damage to tissues in control mice, besides a decrease in weight gain and mild hypoalbuminemia without proteinuria. Thus, DTBN significantly improved renal failure and inflammation indices in CKD mice. Therefore, this and similar substances may be considered as an additional treatment in CKD patients.

The Vital Role of Clinical Examination in Unmasking Bell's Palsy: Beyond Pattern Recognition

While multiple sclerosis (MS) commonly manifests with optic nerve involvement, it can also masquerade as diverse cranial nerve (CN) palsies. We present the case of a young male initially diagnosed with Bell's palsy based on unilateral facial nerve paralysis. Despite the presence of typical clinical features, the patient's evaluation took an unexpected turn. Subsequent brain MRI revealed demyelinating lesions, ultimately confirming the diagnosis of MS. This case underscores the importance of maintaining vigilance in diagnosing atypical presentations of MS, illustrating how meticulous evaluation and neuroimaging play pivotal roles in uncovering underlying pathologies when conventional diagnoses such as Bell's palsy raise uncertainties.

Incremental hemodialysis in pediatric patients

BACKGROUND

Incremental hemodialysis follows the concept of adjusting dialysis dose according to residual kidney function. Data on incremental hemodialysis in pediatric patients is lacking.

METHODS

We conducted a retrospective analysis of children initiating hemodialysis between January 2015 and July 2020 in a single tertiary center, comparing the characteristics and outcomes of those who commenced with incremental hemodialysis vs with conventional thrice-weekly regimen.

RESULTS

Data on forty patients, 15 (37.5%) on incremental hemodialysis and 25 (63%) on thrice-weekly hemodialysis were analyzed. No differences in age, estimated glomerular filtration rate and metabolic parameters were noted between groups at baseline, but there were more males (73 vs 40%, p = 0.04), more patients with congenital anomalies of kidney and urinary tract (60 vs 20%, p = 0.01), higher urine output (2.5 ± 1 vs 1 ± 0.8 ml/kg/h, p < 0.001), lower use of antihypertensive medications (20 vs 72%, p = 0.002) and lower prevalence of left ventricular hypertrophy (6.7 vs 32%, p = 0.003) in the incremental hemodialysis group vs thrice-weekly hemodialysis. During follow up, 5 (33%) incremental hemodialysis patients were transplanted, 1 (7%) remained on incremental hemodialysis at 24 months, and 9 (60%) transitioned to thrice-weekly hemodialysis at a median (IQR) time of 8.7 (4.2, 11.8) months. At last follow up, fewer patients who initiated incremental hemodialysis had left ventricular hypertrophy (0 vs 32%, p = 0.016) and urine output < 100 ml/24 h (20 vs 60%, p = 0.02) compared to thrice-weekly hemodialysis, with no significant differences in metabolic or growth parameters.

CONCLUSION

Incremental hemodialysis is a viable option for initiating dialysis in selected pediatric patients, that may help improve patients' quality of life and reduce dialysis burden without compromising clinical outcome.

Beneficiary Effects of Colchicine on Inflammation and Fibrosis in a Mouse Model of Kidney Injury

INTRODUCTION

Low-grade inflammation is seen in many chronic illnesses, including chronic kidney disease (CKD). We have recently reported on beneficiary effects of anti-inflammatory treatment in the interleukin (IL-) 1 pathway on anemia as well as CKD extent in a mouse model. Colchicine has been shown to have beneficiary effects in several inflammatory conditions through various mechanisms, including inhibition of tubulin polymerization as well as caspase-1-mediated IL-1 activation.

METHODS

Kidney injury (KI) was induced by administering an adenine diet to 8-week-old C57BL/6J mice treated with colchicine (Col) (30 µg/kg) or saline injections for 3 weeks, generating 4 groups: C, Ccol, KI, and KIcol.

RESULTS

KI animals had an increase in inflammation indices in the blood (neutrophils), liver, and kidneys (uromodulin, IL-6, pSTAT3). Increased kidney tubulin polymerization and caspase-1 in KI, as well as kidney Mid88 and IRAK4 (downstream of IL-1), were inhibited in KIcol. Kidney macrophage and polymorphonuclear infiltration (positive for F4/80 and MPO, respectively), the percentage of fibrotic area, and TGFβ mRNA levels were lower in KIcol versus KI.

CONCLUSIONS

Colchicine inhibited tubulin polymerization and caspase-1 activation and attenuated kidney inflammation and fibrosis in a mouse model of adenine-induced KI. Given its reported safety profile for long-term anti-inflammatory therapy without increasing infection tendency, it may serve as novel therapeutic approach in CKD.

Serologic response to COVID-19 infection or vaccination in pediatric kidney transplant recipients compared to healthy children

BACKGROUND

Differences in serologic response to COVID-19 infection or vaccination were reported in adult kidney transplant recipients (KTR) compared to non-immunocompromised patients. This study aims to compare the serologic response of naturally infected or vaccinated pediatric KTR to that of controls.

METHODS

Thirty-eight KTR and 42 healthy children were included; aged ≤18 years, with a previously confirmed COVID-19 infection or post COVID-19 vaccination. Serological response was measured by anti-spike protein IgG antibody titers. Response post third vaccine was additionally assessed in KTR.

RESULTS

Fourteen children in each group had previously confirmed infection. KTR were significantly older and developed a 2-fold higher antibody titer post-infection compared to controls [median (interquartile range [IQR]) age: 14.9 (7.8, 17.5) vs. 6.3 (4.5, 11.5) years, p = 0.02; median (IQR) titer: 1695 (982, 3520) vs. 716 (368, 976) AU/mL, p = 0.03]. Twenty-four KTR and 28 controls were vaccinated. Antibody titer was lower in KTR than in controls [median (IQR): 803 (206, 1744) vs. 8023 (3032, 30,052) AU/mL, p < 0.001]. Fourteen KTR received third vaccine. Antibody titer post booster in KTR reached similar levels to those of controls post two doses [median (IQR) 5923 (2295, 12,278) vs. 8023 (3034, 30,052) AU/mL, p = 0.37] and to KTR post natural infection [5282 AU/mL (2583, 13,257) p = 0.8].

CONCLUSION

Serologic response to COVID-19 infection was significantly higher in KTR than in controls. Antibody level in KTR was higher in response to infection vs. vaccination, contrary to reports in the general population. Response to vaccination in KTR reached levels comparable to controls only after third vaccine.

Idiopathic infantile hypercalcemia in children with chronic kidney disease due to kidney hypodysplasia

BACKGROUND

Idiopathic infantile hypercalcemia (IIH) etiologies include pathogenic variants in CYP24A1, leading to increased 1,25(OH)₂ D, hypercalciuria and suppressed parathyroid hormone (PTH), and in SLC34A1 and SLC34A3, leading to the same metabolic profile via increased phosphaturia. IIH has not been previously described in CKD due to kidney hypodysplasia (KHD).

METHODS

Retrospective study of children with bilateral KHD and simultaneously tested PTH and 1,25(OH)₂D, followed in a tertiary care center between 2015 and 2021.

RESULTS

Of 295 screened patients, 139 had KHD, of them 16 (11.5%) had IIH (study group), 26 with normal PTH and any 1,25(OH)₂D were controls. There were no differences between groups' gender, obstructive uropathy rate and baseline eGFR. Study patients were younger [median (IQR) age: 5.2 (3.2-11.3) vs. 61 (13.9-158.3) months, p < 0.001], had higher 1,25(OH)₂D (259.1 ± 91.7 vs. 156.5 ± 46.4 pmol/l, p < 0.001), total calcium (11.1 ± 0.4 vs. 10.7 ± 0.3 mg/dl, p < 0.001), and lower phosphate standard deviation score (P-SDS) [median (IQR): - 1.4 (- 1.9, - 0.4) vs. - 0.3 (- 0.8, - 0.1), p = 0.03]. During 12 months of follow-up, PTH increased among the study group (8.8 ± 2.8 to 22.7 ± 12.4 pg/ml, p < 0.001), calcium decreased (11 ± 0.5 to 10.3 ± 0.6 mg/dl, p = 0.004), 1,25(OH)₂D decreased (259.5 ± 91.7 to 188.2 ± 42.6 pmol/l, p = 0.1), P-SDS increased [median (IQR): - 1.4 (- 1.9, - 0.4) vs. - 0.3 (- 0.9, 0.4), p = 0.04], while eGFR increased. Five of 9 study group patients with available urine calcium had hypercalciuria. Five patients had nephrocalcinosis/lithiasis. Genetic analysis for pathogenic variants in CYP24A1, SLC34A1 and SLC34A3 had not been performed.

CONCLUSIONS

Transient IIH was observed in infants with KHD, in association with hypophosphatemia, resembling SLC34A1 and SLC34A3 pathogenic variants' metabolic profile. A higher resolution version of the Graphical abstract is available as Supplementary information.

Dialysis in Israeli Children between 1990 and 2020: Trends and International Comparisons

BACKGROUND

Childhood kidney failure is a rare condition with worldwide clinical variability. We used a nationwide multicenter analysis to study the pretransplant course of the entire Israeli pediatric kidney failure population over 30 years.

METHODS

In this nationwide, population-based, historical cohort study, we analyzed medical and demographic data of all children treated with KRT and reported to the Israeli kidney failure registry in 1990-2020. Statistical analysis was performed with incidence rate corrected for age, ethnicity, and calendar year, using the appropriate age-related general population as denominator.

RESULTS

During the last 30 years, childhood incidence of kidney failure decreased. Average incidence in 2015-2019 was 9.1 cases per million age-related population (pmarp). Arab and Druze children exhibited higher kidney failure incidence rates than Jewish children (18.4 versus 7.0 cases pmarp for minorities versus Jews). The most common kidney failure etiologies among Arab and Jewish children were congenital anomalies of the kidney and urinary tract (approximately 27%), followed by cystic kidney diseases among Arab children (13%) and glomerulonephritis among Jewish children (16%). The most common etiology among Druze children was primary hyperoxaluria type 1 (33%). Israel's national health insurance provides access to primary health care to all citizens. Accordingly, waiting time for deceased-donor transplantation was equal between all ethnicities. Living-donor kidney transplantation rates among minority populations remained low in comparison with Jews over the entire study period. Although all patient groups demonstrated improvement in survival, overall survival rates were mainly etiology dependent.

CONCLUSIONS

In Israel, Arab and Druze children had a higher incidence of kidney failure, a unique etiological distribution, and a lower rate of living-donor kidney transplantations compared with Jewish children.

Important Clues for the Diagnosis of Anti-LGI1-Antibody Autoimmune Encephalitis: A Case Report

Anti-leucine-rich-glioma-inactivated 1 (LGI1) antibody autoimmune encephalitis is a rare autoimmune encephalitis. We present a 68-year-old female patient who initially presented with episodic confusion, hallucinations, behavioral changes, and unexplained hyponatremia. History was also remarkable for intermittent abnormal movement affecting the left upper extremity and face. She was initially thought to be suffering from dementia and was discharged home. However, progressive symptoms led to her second admission, where evidence of autonomic dysfunction with episodic bradycardia and persistent symptomatic orthostatic hypotension were evident. Generalized cortical hyperexcitability and subclinical seizures were seen. Diagnosis of LGI1 encephalitis was confirmed with a positive Anti-LGI1 antibody in the cerebrospinal fluid, and treatment with intravenous immunoglobulin and steroids improved her cognitive function. This case helps to highlight important features that should raise early clinical suspicion of LGI1 encephalitis, including unexplained progressive hyponatremia, autonomic dysfunction, and frequent refractory seizures. This can lead to earlier recognition of this condition, where earlier implementation of immunosuppressive therapy is linked to better clinical outcomes and brain structural preservation.

Cefepime-Induced Neurotoxicity Can Be Confused With Neuroleptic Malignant Syndrome, Catatonia and Serotonin Syndrome: A Case Report

Cefepime is a commonly used antibiotic. However, cefepime-induced neurotoxicity (CIN) is less commonly recognized. We describe a 75-year-old female on sertraline and risperidone who has been on cefepime for 28 days for treatment of osteomyelitis and presented with mutism, generalized rigidity, hyperreflexia, generalized stimulus-induced myoclonus, and reactive dilated pupils and found to have developed acute kidney injury. Although the diagnosis of serotonin syndrome (SS) and neuroleptic malignant syndrome (NMS) was suggested initially, the clinical picture was more compatible with CIN. Hemodialysis was suggested but gradual improvement in renal function allowed for gradual neurological recovery. This case highlights the importance of considering CIN in those who have been on Cefepime and present with altered mental status, especially in the appropriate clinical context and presence of risk factors. The overlap in clinical presentation between CIN, SS, NMS, and Catalonia may lead to a diagnostic challenge. Myoclonus seems to be characteristic of CIN and serves as a good clue to hint toward the diagnosis. This case helps to display the similarities and differences in the clinical presentation of these entities and therefore helps avoid confusion and prevents unnecessary therapeutic interventions.

Desvenlafaxine As the Main Possible Culprit in Triggering Reversible Cerebral Vasoconstriction Syndrome: A Case Report

Reversible cerebral vasoconstriction syndrome (RCVS) is not an uncommon condition. It should be suspected in young patients with new onset headaches and neurologic deficits. We report a 38-year-old male patient with a history of depression on desvenlafaxine for two years and no other triggering factor who was diagnosed with RCVS confirmed by cerebral angiogram. Discontinuation of the medication and calcium channel blockers initiation led to rapid clinical improvement. The diagnosis was further confirmed by angiographic improvement two months later. Although the association of selective serotonin reuptake inhibitors (SSRI)/ serotonin norepinephrine reuptake inhibitors (SNRI) with RCVS has been reported frequently, desvenlafaxine is a much less reported trigger, with only nine cases in total. In contrast to prior reported cases where the time from exposure to onset of RCVS was weeks to months, the time interval, in this case, was two years. This case report aims to support previous literature in suggestion of this association.

Risk factors for childhood chronic kidney disease: a population-based study

BACKGROUND

The population-based prevalence and risk factors of childhood chronic kidney disease (CKD) are not well-defined. We ascertained childhood CKD epidemiology and perinatal risk factors, based on a large computerized medical record database that covers most of southern Israel's population.

METHODS

Pre- and post-natal records of 79,374 eligible children (with at least one serum creatinine test) born during 2001-2015 were analyzed. "Ever-CKD" was defined as ≥ 2 estimated glomerular filtration rate (eGFR) values < 60 ml/min/1.73 m² beyond age 2 years, more than 3 months apart. The last CKD status was determined on March 2019.

RESULTS

Of 82 (0.1%) patients with ever-CKD, 35 (42.7%) had their first abnormal eGFR identified already at age 2 years. In multiple logistic regression analysis, congenital anomalies of kidney and urinary tract (CAKUT)-related diagnoses, glomerulopathy, maternal oligohydramnios, small for gestational age, prematurity (under 34 weeks), post-term delivery, and small for gestational age at birth were significant risk factors for ever-CKD (odds ratio (95% confidence interval): 44.34(26.43-74.39), 64.60(32.42-128.70), 5.54(3.01-10.19), 2.02(1.25-3.28), 4.45(2.13-9.28), 2.96(1.28-6.86 and 2.02(1.25-3.28), respectively). Seventy children with ever-CKD (85.4%) had a depressed eGFR (< 90 ml/min/1.73 m²) on the last assessment (current-CKD), yielding a prevalence of 882/million.

CONCLUSIONS

CKD is more prevalent among children in southern Israel than previously reported, even after excluding those with aborted-CKD. Prenatal conditions increase the risk to develop CKD in childhood. Graphical abstract A higher resolution version of the Graphical abstract is available as Supplementary information.

MO527: The Active Ingredient in the Nuphar Lutea Plant, 6,6′: Dihydroxythiobinupharidine (DTBN) Ameliorates Kidney Fibrosis, Inflammation and Anemia in a Mouse Model of Chronic Kidney Disease (CKD)

BACKGROUND AND AIMS

EPO resistance and iron deficiency in CKD-related anemia are associated with an increase in inflammatory cytokines associated with the innate immune response, such as IL-6, IL-1 and TNF-α. Recently (Bandach et al. Sci Reports 2021) we reported that kidney fibrosis and anemia of CKD can be worsened or relieved when IL1 effects are enhanced or inhibited respectively.

The Water lily (Nuphar lutea) plant has been widely used as a traditional remedy for the treatment of rheumatism, scars, pain and more. Gopas, Golan-Goldhirsh et al. (Cancer Biology Therapy 2009) extracted an active ingredient from the family of nupharidines: 6,6′-Dihydroxythiobinupharidine (DTBN), which showed anti-inflammatory properties, mainly through the inhibition of NF-κB. The purpose of this study was to test the effects of DTBN in a mouse model of CKD-associated anemia.

METHOD

8 weeks old male C57BL/6 mice were divided into three groups: control, CKD (induced by adenine diet) and CKD-DTBN. CKD groups were injected with saline-DMSO or 30 µg DTBN, every 2 days and sacrificed after 3 weeks from dietary intervention.

RESULTS

Serum urea and kidney TGFβ mRNA were significantly decreased in CKD- DTBN versus CKD. Kidney histology in CKD mice showed macrophage infiltration and renal fibrosis, which was ameliorated in CKD-DTBN.

A significant improvement in inflammation indices (blood lymphocytes, kidney and liver IL-6 and p-STAT3, liver CRP), as well as kidney immunoreactive NF-κB and F4\80, which were increased in CKD, were decreased in CKD-DTBN. CKD anemia indices (hemoglobin, hematocrit and red blood cell (RBC) count) significantly improved in CKD-DTBN. Kidney HIF-2α and EPO mRNA were significantly decreased in both uremic groups, but was unchanged in CKD- DTBN versus CKD. However, serum iron and transferrin saturation significantly increased in CKD-DTBN versus CKD.

CONCLUSION

Uremic mice treated with DTBN show improvement in kidney fibrosis, inflammation and anemia indices. Thus, DTBN may be a novel therapeutic alternative for CKD and its complications.

EBV, CMV, and BK viral infections in pediatric kidney transplantation: Frequency, risk factors, treatment, and outcomes

BACKGROUND

Improved short- and long-term outcomes of kidney transplantation have been achieved over the past decades due to improved immunosuppression. This may have increased the risk for infections and, particularly, for the viral infections: cytomegalovirus (CMV), Epstein-Barr virus (EBV), and polyoma BK virus (BKV).

METHODS

A retrospective review of viremic CMV, EBV, and BKV infections in pediatric renal transplant recipients treated and followed by a national referral center over a 10-year period.

RESULTS

Sixty-seven patients (68% males) received 68 kidney grafts (62% from living donors) during the study period; the mean follow-up period was 5.2 ± 2.4 years. Twenty-seven viremic episodes were documented (CMV: 13, EBV: 6, BKV: 8) in 24 patients (35.2%). The median time (interquartile range) to viremia post-transplant was 11 (4-38) months. The viral infection rate was significantly higher in the years 2014-2015 than in previous years (61% vs. 29%, p = .017). Compared to patients who did not develop viremia, patients with viremias were younger at the time of transplantation, were more likely to receive thymoglobulin induction pre-transplant and to develop an acute rejection. Multiple logistic regression modeling identified transplant year and recipient's age as significant risk factors for viremia. Graft outcome and eGFR at the last follow-up was similar between patients who did and did not develop viremia.

CONCLUSIONS

Viral infections continue to be a major cause of morbidity in pediatric kidney transplant recipients. However, with close monitoring and prompt intervention, patient and renal outcomes remain favorable.

Psoriasis and Renal Disorders: A Large-Scale Population-Based Study in Children and Adults

Background

Psoriasis is a systemic disease with associated comorbidities. An association between renal diseases and psoriasis has previously been reported in adult patients, but little is known about renal diseases in pediatric patients.

Objective

To determine whether there is an association between psoriasis and renal comorbidities in adult and pediatric patients.

Methods

This cross-sectional study analyzed the database of the largest health care maintenance organization in Israel. Logistic regression was used to calculate odds ratios to compare 68,836 psoriatic patients and 68,836 controls with respect to renal comorbidities.

Results

In adults, an inverse association emerged between psoriasis and dialysis (OR, 0.69; 95% CI, 0.58–0.83) and kidney transplantation (OR, 0.60; 95% CI, 0.43–0.83), a positive association with other kidney diseases (OR, 1.09; 95% CI, 1.05–1.13), and no association between psoriasis and chronic kidney disease (OR, 1.03; 95% CI, 0.98–1.09). Comparing 9,127 pediatric patients and 9,478 controls, no association was found between psoriasis and renal comorbidities, chronic kidney disease (OR, 0.90; 95% CI, 0.33–2.48), dialysis (OR, 2.06; 95% CI, 0.19–22.69), kidney transplantation (OR, 0.34; 95% CI, 0.04–3.29), or other kidney diseases (OR, 0.98; 95% CI, 0.79–1.23), even after a multivariate analysis adjusting for putative confounders.

Conclusion

As opposed to adult patients, pediatric patients with psoriasis were not shown at risk of kidney diseases.

[RENAL TUBULAR DYSGENESIS SECONDARY TO MUTATIONS IN GENES ENCODING THE RENIN-ANGIOTENSIN SYSTEM]

Autosomal recessive renal tubular dysgenesis (RTD;OMIM: 267430) is a rare kidney disease secondary to mutations in genes encoding the renin-angiotensin system which have a role in renal tissue development during fetal life and in the maintenance of blood pressure and electrolyte balance. The disease is characterized by oligohydramnios, prematurity, neonatal renal failure, hypotension and abnormalities in cranial bone development. Nearly all affected individuals die either in-utero or within the first few days of life, although a few long term survivors were reported during the last decade. We describe the management of 5 newborns diagnosed with RTD in pregnancy who survived the neonatal period, four of them belong to an extended Bedouin family. In 4/5 patients we identified a mutation in angiotensin converting enzyme (ACE) gene. Variable presentation was noticed in the patients, starting with peritoneal dialysis and extreme low blood pressure treated with vasopressors and plasma infusions and ending with no symptoms. Currently, the patients are 5-20 years old with variable stages of chronic kidney disease. In conclusion, the spectrum of RTD is wider than previously reported. Prompt diagnosis is necessary for optimal decision-making by families and physicians. Intensive treatment of low blood pressure in the postnatal period is critical for their survival and better prognosis.

Clinical Outcomes and Antibody Response in COVID-19-Positive Pediatric Solid Organ Transplant Recipients

We describe the clinical and laboratory manifestations and outcomes of 25 pediatric solid organ transplant recipients who tested positive for severe acute respiratory coronavirus-2. Twenty-one (84%) developed a mild disease; 22 of 23 (96%) had a positive serologic response. Two patients (8%), both kidney transplant recipients with additional comorbidities, developed a severe disease. The findings emphasize the need for close monitoring of this population.

[NEPHROTIC SYNDROME RECURRENCE POST-RENAL TRANSPLANTATION: 10 YEARS' EXPERIENCE AT SCHNEIDER CHILDREN'S MEDICAL CENTER IN ISRAEL]

INTRODUCTION

A total of 30-50% of pediatric patients presenting with steroid resistant nephrotic syndrome (SRNS) will reach end stage renal disease (ESRD). In patients with primary SRNS, the risk of post-transplant recurrence is around 60% with poor graft outcomes. In the past decade new treatment modalities have emerged in an attempt to improve graft outcomes.

AIMS

To describe the clinical experience at the Schneider Children's Medical Center in Israel in treating children with post-transplant recurrent SRNS in the past decade, and compare its results to a similar study conducted at the same center in previous years.

METHODS

A retrospective chart review was conducted. Data regarding demographic characteristics, clinical course and treatment modalities of patients with post-transplant recurrent SRNS were extracted from patients' charts.

RESULTS

Eight patients with post-transplant recurrent SRNS were identified. Median age at initial nephrotic syndrome presentation was 4 (range: 0.8-15) years. Median time to reach ESRD was 43 (range: 12-132) months. All patients were treated with plasmapheresis, seven patients were treated with Rituximab. Low-density lipoprotein (LDL) apheresis, Ofatumumab and Abatacept were used in 1-2 patients each. Median follow-up time post-transplant was 47 (range: 15-93) months. Four patients (50%) responded to treatment, two achieved complete and two partial remission. Four patients reached ESRD within a median time of 24 (range: 12-84) months. Lower rates of acute tubular necrosis and immediate graft loss were observed during the last decade compared to previous years (37.5% vs. 64%; 0% vs. 28.6% respectively).

CONCLUSIONS

Post-transplant recurrence of SRNS continues to pose a significant treatment challenge. Similar to previous reports, only 50% of our patients responded to treatment while 50% were unresponsive to all treatment modalities and reached ESRD. Immediate post-operative management improved over the last decade, however long-term outcome continues to be grim. There is a need to better identify disease mechanisms that will allow us to tailor more effective treatment modalities to improve patients' outcome.

Growth Hormone and IGF1 Actions in Kidney Development and Function

Growth hormone (GH) exerts multiple effects on different organs including the kidneys, either directly or via its main mediator, insulin-like-growth factor-1 (IGF-1). The GH/IGF1 system plays a key role in normal kidney development, glomerular hemodynamic regulation, as well as tubular water, sodium, phosphate, and calcium handling. Transgenic animal models demonstrated that GH excess (and not IGF1) may lead to hyperfiltration, albuminuria, and glomerulosclerosis. GH and IGF-1 play a significant role in the early development of diabetic nephropathy, as well as in compensatory kidney hypertrophy after unilateral nephrectomy. Chronic kidney disease (CKD) and its complications in children are associated with alterations in the GH/IGF1 axis, including growth retardation, related to a GH-resistant state, attributed to impaired kidney postreceptor GH-signaling and chronic inflammation. This may explain the safety of prolonged rhGH-treatment of short stature in CKD.

Serological Response to the BNT162b2 COVID-19 mRNA Vaccine in Adolescent and Young Adult Kidney Transplant Recipients

BACKGROUND

Initial reports in adult kidney transplant recipients (KTR) indicate low immunogenicity after 2 doses of the BNT162b2 COVID-19 mRNA vaccine. We describe the immunogenicity of this vaccine compared to the serologic response in naturally infected COVID-19 positive adolescent and young adult KTR.

METHODS

For this prospective observational study, the study group included 38 KTR who received 2 doses of the tested vaccine, and the control group included 14 KTR who had a previous polymerase chain reaction-confirmed COVID-19 infection.

RESULTS

The mean age was 18 ± 3 y. Positive serologic responses were observed in 63% and 100% of the study and control groups, respectively (P = 0.01). Antibody titers were almost 30-fold higher in the control than the study group (median [interquartile range (IQR)]: 2782 [1908-11 000] versus 100.3 [4.7-1744] AU/mL, P < 0.001), despite the longer time from the COVID-19 infection to serologic testing compared to time from vaccination (median [IQR]: 157.5 [60-216] versus 37 [20.5-53] d, P = 0.011). Among vaccinated patients, higher proportions of those seronegative than seropositive were previously treated with rituximab (50% versus 8%, P = 0.01). Time from the second vaccine dose to serologic testing was longer in seropositive than seronegative patients (median [IQR]: 24.5 [15-40] versus 46 [27-56] d, P = 0.05). No patient developed symptomatic COVID-19 disease postvaccination.

CONCLUSIONS

The BNT162b2 COVID-19 mRNA vaccine yielded higher positive antibody response in adolescent and young adult KTR than previously reported for adult KTR. Antibody titers after vaccination were significantly lower than following COVID-19 infection. Longer time may be required to mount appropriate humoral immunity to vaccination in KTR.

Incidence of Impaired Kidney Function Among Adolescent Patients Hospitalized With Anorexia Nervosa

IMPORTANCE

Anorexia nervosa (AN) is a common psychiatric disorder associated with electrolyte imbalances and impaired kidney function, but their incidence and association with disease severity are unknown.

OBJECTIVE

To analyze kidney function in patients with AN and its association with body mass index (BMI) and physiologic parameters of disease severity.

DESIGN, SETTING, AND PARTICIPANTS

Single-center retrospective case-control study of recently hospitalized patients with a diagnosis of AN according to International Classification of Diseases, Ninth Revision. All patients were aged 9 to 18 years and hospitalized in the general pediatric ward between 2010 and 2019. BMI and estimated glomerular filtration rate (eGFR) were compared with age- and sex-matched controls hospitalized with other diagnoses.

MAIN OUTCOMES AND MEASURES

Impaired kidney function was defined as eGFR less than 90 mL/min/1.73 m2. Association between eGFR, BMI, minimal heart rate, and free triiodothyronine (T3) levels were determined using logistic regression.

RESULTS

A total of 395 patients were included in the study group (81.6% were female; mean [SD] age, 14.6 [2.2] years; median BMI percentile, 12.3 [IQR, 0.9-42.0]). Impaired kidney function was found in 36.8% (146 of 395). Mean (SD) eGFR decreased during hospitalization in the group with kidney function impairment (admission: 83 [10.9] mL/min/1.73 m2; nadir: 79.1 [8.5] mL/min/1.73 m2; latest: 97.7 [15.7] mL/min/1.73 m2; P < .001). Mean (SD) serum creatinine (SCr) to BMI ratio was higher in both anorexia groups compared with controls in impaired kidney function (4.9% [1.0%]), non-impaired kidney function (3.55% [0.84%]); and control groups (2.8 [1.1%]) (P < .001). There was no difference in admission BMI between anorexia groups with and without kidney function impairment. Mean (SD) free T3 levels (3.5 [0.2] pmol/L vs 4.08 [1.2] pmol/L; P < .001) and mean (SD) minimal heart rate (44 [11] beats per min vs 56 [16] beats per min; P < .001) were lower and hospital stay was longer (median, 13 [IQR, 6-21] days vs 8 [IQR, 4-19] days; P = .03) in the impaired kidney function group. The highest correlation was found between minimal heart rate and minimal eGFR (R = 0.53; P < .001).

CONCLUSIONS AND RELEVANCE

Impaired kidney function in patients with AN is common and transiently worsens during hospitalization. SCr values probably underestimate the degree of kidney function impairment in AN. Results of this study found that patients with impaired kidney function had worse anorexia severity parameters unrelated to admission BMI. Therefore, kidney function impairment may be a better marker of anorexia severity.

Is the prognosis of congenital single functioning kidney benign? A population-based study

BACKGROUND

We investigated the risk of kidney injury among adolescents with and without a congenital single functioning kidney (SFK).

METHODS

This retrospective study is based on a medical evaluation database of 17-year-old Israeli conscripts, born during 1989-1999. Those with congenital SFK diagnosis, verified by a pediatric nephrologist's review of the original military medical committee classifications, were compared to the rest of the cohort. Kidney injury (KI) was defined as proteinuria, high blood pressure (BP), or estimated glomerular filtration rate (eGFR) < 90 ml/min/1.73 m² prior to army recruitment. Risk factors for KI were examined using logistic regression.

RESULTS

Of 979,630 screened candidates, 353 were diagnosed with SFK. The yearly incidence of SFK gradually increased in the first years of the study, reaching a plateau in 1995 (5.5 ± 1.2/10,000 births/year). The male to female ratio was 2.7:1. Concomitant genital malformations were documented in 5.5% of those with SFK. KI was more prevalent in the SFK than the control group (42.2% vs. 23.5%, p < 0.001). All three components of KI were more common in the SFK than the control group: high BP (31.7% vs. 23.1%, p < 0.001), proteinuria (18.2% vs. 0.4%, p < 0.001), and eGFR <90 ml/min/1.73m² (12.0% vs 0.1%, p < 0.001). Multivariate analysis of the SFK group revealed associations of higher mean BMI, male sex, and smaller ultrasonographic kidney length with KI.

CONCLUSIONS

This large population-based study documents a significant risk for KI among adolescents with SFK. Obesity represents a major modifiable risk factor for KI, implicating the need for closer follow-up in this group during childhood.

A multichannel feature-based approach for longitudinal lung CT registration in the presence of radiation induced lung damage

Quantifying parenchymal tissue changes in the lungs is imperative in furthering the study of radiation induced lung damage (RILD). Registering lung images from different time-points is a key step of this process. Traditional intensity-based registration approaches fail this task due to the considerable anatomical changes that occur between timepoints. This work proposes a novel method to successfully register longitudinal pre- and post-radiotherapy (RT) lung computed tomography (CT) scans that exhibit large changes due to RILD, by extracting consistent anatomical features from CT (lung boundaries, main airways, vessels) and using these features to optimise the registrations. Pre-RT and 12 month post-RT CT pairs from fifteen lung cancer patients were used for this study, all with varying degrees of RILD, ranging from mild parenchymal change to extensive consolidation and collapse. For each CT, signed distance transforms from segmentations of the lungs and main airways were generated, and the Frangi vesselness map was calculated. These were concatenated into multi-channel images and diffeomorphic multichannel registration was performed for each image pair using NiftyReg. Traditional intensity-based registrations were also performed for comparison purposes. For the evaluation, the pre- and post-registration landmark distance was calculated for all patients, using an average of 44 manually identified landmark pairs per patient. The mean (standard deviation) distance for all datasets decreased from 15.95 (8.09) mm pre-registration to 4.56 (5.70) mm post-registration, compared to 7.90 (8.97) mm for the intensity-based registrations. Qualitative improvements in image alignment were observed for all patient datasets. For four representative subjects, registrations were performed for three additional follow-up timepoints up to 48 months post-RT and similar accuracy was achieved. We have demonstrated that our novel multichannel registration method can successfully align longitudinal scans from RILD patients in the presence of large anatomical changes such as consolidation and atelectasis, outperforming the traditional registration approach both quantitatively and through thorough visual inspection.

Genetic renal disease classification by hormonal axes

The kidneys, which regulate many homeostatic pathways, are also a major endocrinological target organ. Many genetic renal diseases can be classified according to the affected protein along such endocrinological pathways. In this review, we examine the hypothesis that a more severe phenotype is expected as the affected protein is located more distally along such pathways. Thus, the location of a defect along its endocrinological pathway should be taken into consideration, in addition to the mutation type, when assessing genetic renal disease severity.

In Silico Ventilation Within the Dose-Volume is Predictive of Lung Function Post-radiation Therapy in Patients with Lung Cancer

Lung cancer is a leading cause of death worldwide. Radiation therapy (RT) is one method to treat this disease. A common side effect of RT for lung cancer is radiation-induced lung damage (RILD) which leads to loss of lung function. RILD often compounds pre-existing smoking-related regional lung function impairment. It is difficult to predict patient outcomes due to large variability in individual response to RT. In this study, the capability of image-based modelling of regional ventilation in lung cancer patients to predict lung function post-RT was investigated. Twenty-five patient-based models were created using CT images to define the airway geometry, size and location of tumour, and distribution of emphysema. Simulated ventilation within the 20 Gy isodose volume showed a statistically significant negative correlation with the change in forced expiratory volume in 1 s 12-months post-RT (p = 0.001, R = - 0.61). Patients with higher simulated ventilation within the 20 Gy isodose volume had a greater loss in lung function post-RT and vice versa. This relationship was only evident with the combined impact of tumour and emphysema, with the location of the emphysema relative to the dose-volume being important. Our results suggest that model-based ventilation measures can be used in the prediction of patient lung function post-RT.

Hyperuricemia and gout caused by missense mutation in d-lactate dehydrogenase

Gout is caused by deposition of monosodium urate crystals in joints when plasma uric acid levels are chronically elevated beyond the saturation threshold, mostly due to renal underexcretion of uric acid. Although molecular pathways of this underexcretion have been elucidated, its etiology remains mostly unknown. We demonstrate that gout can be caused by a mutation in LDHD within the putative catalytic site of the encoded d-lactate dehydrogenase, resulting in augmented blood levels of d-lactate, a stereoisomer of l-lactate, which is normally present in human blood in miniscule amounts. Consequent excessive renal secretion of d-lactate in exchange for uric acid reabsorption culminated in hyperuricemia and gout. We showed that LDHD expression is enriched in tissues with a high metabolic rate and abundant mitochondria and that d-lactate dehydrogenase resides in the mitochondria of cells overexpressing the human LDHD gene. Notably, the p.R370W mutation had no effect on protein localization. In line with the human phenotype, injection of d-lactate into naive mice resulted in hyperuricemia. Thus, hyperuricemia and gout can result from the accumulation of metabolites whose renal excretion is coupled to uric acid reabsorption.

SOCS2 Silencing Improves Somatic Growth without Worsening Kidney Function in CKD

BACKGROUND

Growth hormone (GH) resistance in CKD is partly due to increased expression of SOCS2, a GH signaling negative regulator. In SOCS2 absence, body growth is exaggerated. However, GH overexpression in mice causes glomerulosclerosis. Accordingly, we tested whether lack of SOCS2 improves body growth, but accelerates kidney damage in CKD.

METHODS

Eight-week-old mutant SOCS2-deficient high growth (HG) and normal wild-type mice (N) underwent 5/6 nephrectomy (CKD) or sham operation (C) and were sacrificed after 12 weeks, generating 4 groups: C-N, C-HG, CKD-N, CKD-HG.

RESULTS

Somatic growth, inhibited in CKD-N, increased significantly in CKD-HG. Liver p-STAT5, a key intracellular signal of GH receptor (GHR) activation, was decreased in CKD-N but not in CKD-HG. Serum Cr as well as histopathological scores of renal fibrosis were similar in both CKD groups. Kidney fibrogenic (TGF-β and collagen type IV mRNA) and inflammatory precursors (IL6, STAT3, and SOCS3 mRNA) were similarly increased in C-HG, CKD-HG, and CKD-N versus C-N. Renal GHR mRNA was decreased in C-HG, CKD-HG, and CKD-N versus C-N. Kidney p-STAT5 was decreased in CKD-N but not elevated in CKD-HG.

CONCLUSIONS

CKD-related growth retardation is overcome by SOCS2 silencing, in association with increased hepatic STAT5 phosphorylation. Renal insufficiency is not worsened by SOCS2 absence, as kidney GHR and STAT5 are not upregulated. This may be due to elevated kidney proinflammatory cytokines and their mediators, phospho-STAT3 and SOCS3, which may counteract for the absence in SOCS2 and explain the renal safety of prolonged GH therapy in CKD.

An ancestral variant causing type I xanthinuria in Turkmen and Arab families is predicted to prevail in the Afro-Asian stone-forming belt

Classical xanthinuria is a rare autosomal recessive metabolic disorder characterized by lack of xanthine dehydrogenase activity that often manifests as xanthine urolithiasis and risk of drug toxicity. Variants in the XDH or HMCS gene underlie classical xanthinuria type I and type II, respectively. Here we present two Israeli Arab families affected by type I xanthinuria in whom a c.2164A>T (Lys722Ter) variant in the XDH gene, previously reported in a Turkish family of Turkmen origin, was identified. Analysis of polymorphic markers surrounding the variant site revealed common haplotypes spanning 0.6 Mbp shared by all three, and 1.7 Mbp shared by two of the studied families. By applying Bayesian methods to a simple model of crossover events through generations in the chromosomes carrying the variant, the most recent common ancestor of these families was found to be 179 (95% credible limit 70) generations old. The estimated antiquity of the variant, the historical genealogy of the affected families and the history and present day dispersion of their people strongly suggest prevalence of this variant in the Afro‐Asian stone‐forming belt. As far as we are aware, this is a first report of an ancient variant causing xanthinuria with potential wide geographical dispersion.

Prediction of a positive circumferential resection margin at surgery following neoadjuvant chemotherapy for adenocarcinoma of the oesophagus

Background

A positive circumferential resection margin (CRM) has been associated with higher rates of locoregional recurrence and worse survival in oesophageal cancer. The aim of this study was to establish if clinicopathological and radiological variables might predict CRM positivity in patients who received neoadjuvant chemotherapy before surgery for oesophageal adenocarcinoma.

Methods

Multivariable analysis of clinicopathological and CT imaging characteristics considered potentially predictive of CRM was performed at initial staging and following neoadjuvant chemotherapy. Prediction models were constructed. The area under the curve (AUC) with 95% confidence intervals (c.i.) from 1000 bootstrapping was assessed.

Results

A total of 223 patients were included in the study. Poor differentiation (odds ratio (OR) 2·84, 95 per cent c.i. 1·39 to 6·01) and advanced clinical tumour status (T3-4) (OR 2·93, 1·03 to 9·48) were independently associated with an increased CRM risk at diagnosis. CT-assessed lack of response (stable or progressive disease) following chemotherapy independently corresponded with an increased risk of CRM positivity (OR 3·38, 1·43 to 8·50). Additional CT evidence of local invasion and higher CT tumour volume (14 cm3) improved the performance of a prediction model, including all the above parameters, with an AUC (c-index) of 0·76 (0·67 to 0·83). Variables associated with significantly higher rates of locoregional recurrence were pN status (P = 0·020), lymphovascular invasion (P = 0·007) and poor response to chemotherapy (Mandard score 4-5) (P = 0·006). CRM positivity was associated with a higher locoregional recurrence rate, but this was not statistically significant (P = 0·092).

Conclusion

The presence of advanced cT status, poor tumour differentiation, and CT-assessed lack of response to chemotherapy, higher tumour volume and local invasion can be used to identify patients at risk of a positive CRM following neoadjuvant chemotherapy.

The enemy's gaze: Immersive virtual environments enhance peace promoting attitudes and emotions in violent intergroup conflicts

Perspective-taking is essential for improving intergroup relations. However, it is difficult to implement, especially in violent conflicts. Given that immersive virtual reality (VR) can simulate various points of view (POV), we examined whether it can lead to beneficial outcomes by promoting outgroup perspective-taking, even in armed conflicts. In two studies, Jewish-Israelis watched a 360° VR scene depicting an Israeli-Palestinian confrontation from different POVs–outgroup’s, ingroup’s while imagining outgroup perspective or ingroup’s without imagined perspective-taking. Participants immersed in the outgroup’s POV, but not those who imagined the outgroup’s perspective, perceived the Palestinians more positively than those immersed in the ingroup’s POV. Moreover, participants in the outgroup’s POV perceived the Palestinian population in general more favorably and judged a real-life ingroup transgression more strictly than those in the ingroup’s POV, even five months after VR intervention. Results suggest that VR can promote conflict resolution by enabling effective perspective-taking.

Eculizumab Safety: Five-Year Experience From the Global Atypical Hemolytic Uremic Syndrome Registry

Introduction

Eculizumab has transformed outcomes for patients with atypical hemolytic uremic syndrome (aHUS). Its efficacy and safety profile was well characterized in the clinical trial program. The long-term safety profile was not previously assessed or compared against nontreated patients in an observational registry setting.

Methods

The Global aHUS Registry recruits patients with clinical diagnoses of aHUS. This analysis includes baseline characteristics and targeted safety events from adult and pediatric patients who were "ever treated" versus "never treated" with eculizumab in the first 5 years of the registry, through January 26, 2017.

Results

Overall, 1321 patients (adult, n = 842; pediatric, n = 479; ever treated, n = 865; never treated, n = 456) were enrolled. A higher proportion of ever-treated versus never-treated adult and pediatric patients had renal, cardiovascular, pulmonary, central nervous system, gastrointestinal symptoms, and hepatic impairment. No differences in safety event rates between ever-treated and never-treated patients were observed, except serious infections in pediatric patients (5.15 versus 1.12 events/100 patient-years for ever- and never-treated patients, respectively). Deaths were more frequent in adult (4.7% and 9.9% of ever- and never-treated patients) compared with pediatric patients (1.8% of ever-treated patients; no deaths in never-treated patients).Three meningococcal infections were reported in ever-treated patients; 1 infection led to a fatal outcome.

Conclusion

In this large observational dataset covering 5 years of registry enrollment, no new safety concerns were identified for adult or pediatric eculizumab-treated patients with aHUS, confirming a positive benefit-risk profile in a real-world setting.

A novel SLC12A1 mutation in Bedouin kindred with antenatal Bartter syndrome type I

Four affected individuals of consanguineous kindred presented at infancy with an apparently autosomal recessive syndrome of polyuria and hypokalemic metabolic alkalosis, following maternal polyhydramnios and premature delivery, culminating in severe failure to thrive. Hypercalciuria, nephrocalcinosis, and hyperaldosteronism were further apparent as well as an unusual finding of intermittent hypernatremia. Additionally, all patients demonstrated variable micrognathia with upper respiratory airway abnormalities. As neither postnatal hyperkalemia nor permanent hearing deficits were shown, clinical assessment was consistent with antenatal Bartter syndrome (ABS) type I, which was never described before in the Israeli Bedouin population. Through genome-wide linkage analysis, we identified a single ∼3.3 Mbp disease-associated locus on chromosome 15q21.1, segregating within the pedigree. Whole-exome sequencing revealed a single novel homozygous missense mutation within this locus, in SLC12A1, encoding the Na-K-Cl cotransporter, NKCC2, in accordance with the clinical diagnosis. In this concise study, we report a novel missense mutation within the SLC12A1 gene, causing a severe form of ABS type I, the first to be described in Israeli Bedouins, with unusual clinical features of hypernatremia caused by nephrogenic diabetes insipidus and putatively related micrognathia with upper airway abnormalities .

Clinical Approach to Proximal Renal Tubular Acidosis in Children

Proximal renal tubular acidosis (pRTA) is an inherited or acquired clinical syndrome in which there is a decreased bicarbonate reclamation in the proximal tubule resulting in normal anion gap hyperchloremic metabolic acidosis. In children, pRTA may be isolated but is often associated with a general proximal tubular dysfunction known as Fanconi syndrome which frequently heralds an underlying systemic disorder from which it arises. When accompanied by Fanconi syndrome, pRTA is characterized by additional renal wasting of phosphate, glucose, uric acid, and amino acids. The most common cause of inherited Fanconi syndrome in the pediatric age group is cystinosis, a disease with therapeutic implications. In this article, we summarize the clinical presentation and differential diagnosis of pRTA and Fanconi syndrome and provide a practical approach to their evaluation in children.

The hypoxia inducible factor/erythropoietin (EPO)/EPO receptor pathway is disturbed in a rat model of chronic kidney disease related anemia

Objectives

Anemia is a known driver for hypoxia inducible factor (HIF) which leads to increased renal erythropoietin (EPO) synthesis. Bone marrow (BM) EPO receptor (EPOR) signals are transduced through a JAK2-STAT5 pathway. The origins of anemia of chronic kidney disease (CKD) are multifactorial, including impairment of both renal EPO synthesis as well as intestinal iron absorption. We investigated the HIF- EPO- EPOR axis in kidney, BM and proximal tibia in anemic juvenile CKD rats.

Methods

CKD was induced by 5/6 nephrectomy in young (20 days old) male Sprague-Dawley rats while C group was sham operated. Rats were sacrificed 4 weeks after CKD induction and 5 minutes after a single bolus of IV recombinant human EPO. An additional control anemic (C-A) group was daily bled for 7 days.

Results

Hemoglobin levels were similarly reduced in CKD and C-A (11.4 ± 0.3 and 10.8±0.2 Vs 13.5±0.3 g/dL in C, p<0.0001). Liver hepcidin mRNA was decreased in CA but increased in CKD. Serum iron was unchanged while transferrin levels were mildly decreased in CKD. Kidney HIF2α protein was elevated in C-A but unchanged in CKD. Kidney EPO protein and mRNA levels were unchanged between groups. However, BM EPO protein (which reflects circulating EPO) was increased in C-A but remained unchanged in CKD. BM and proximal tibia EPOR were unchanged in C-A but decreased in CKD. Proximal tibial phospho-STAT5 increased after the EPO bolus in C but not in CKD.

Conclusions

Compared to blood loss, anemia in young CKD rats is associated with inappropriate responses in the HIF-EPO-EPO-R axis: kidney HIF2α and renal EPO are not increased, BM and bone EPOR levels, as well as bone pSTAT5 response to EPO are reduced. Thus, anemia of CKD may be treated with additional therapeutic avenues beyond iron and EPO supplementation.

Impact of incremental circumferential resection margin distance on overall survival and recurrence in oesophageal adenocarcinoma

Background

Previous analyses of the oesophageal circumferential resection margin (CRM) have focused on the prognostic validity of two different definitions of a positive CRM, that of the College of American Pathologists (tumour at margin) and that of the Royal College of Pathologists (tumour within 1 mm). This study aimed to analyse the validity of these definitions and explore the risk of recurrence and survival with incremental tumour distances from the CRM.

Methods

This cohort study included patients who underwent resection for adenocarcinoma of the oesophagus between 2000 and 2014. Kaplan-Meier and Cox regression analyses were performed to determine the hazard ratio (HR) with 95 per cent confidence intervals for recurrence and mortality in CRM increments: tumour at the cut margin, extending to within 0·1-0·9, 1·0-1·9, 2·0-4·9 mm, and 5·0 mm or more from the margin.

Results

A total of 444 patients were included in the study. Kaplan-Meier and unadjusted analyses showed a significant incremental improvement in overall survival (P < 0·001) and recurrence (P for trend < 0·001) rates with increasing distance from the CRM. Tumour distance of 2·0 mm or more remained a significant predictor of survival on multivariable analysis (HR for risk of death 0·66, 95 per cent c.i. 0·44 to 1·00). Multivariable analysis of overall survival demonstrated a significant difference between a positive and negative CRM with the Royal College of Pathologists' definition (HR 1·37, 1·01 to 1·85), but not with the College of American Pathologists' definition (HR 1·22, 0·90 to 1·65).

Conclusion

This study demonstrated an incremental improvement in survival and recurrence rates with increasing tumour distance from the CRM.