Buffy Coat DNA Methylation Profile Is Representative of Methylation Patterns in White Blood Cell Types in Normal Pregnancy

Background: We aimed to assess the extent to which the buffy coat DNA methylome is representative of methylation patterns in constitutive white blood cell (WBC) types in normal pregnancy. Methods: A comparison of differential methylation of buffy coat DNA vs DNA isolated from polymorphonuclear (PMN) and lymphocytic fractions was performed for each blood sample obtained within 24 h prior to delivery from 29 normotensive pregnant women. Methylation profiles were obtained using an Illumina Human Methylation 450 BeadChip and CHaMP bioinformatics pipeline. A subset of differentially methylated probes (DMPs) showing discordant methylation were further investigated using statistical modeling and enrichment analysis. Results: The smallest number of DMPs was found between the buffy coat and the PMN fraction (2.96%). Pathway enrichment analysis of the DMPs identified biological pathways involved in the particular leukocyte lineage, consistent with perturbations during isolation. The comparisons between the buffy coat and the isolated fractions as a group using linear modeling yielded a small number of probes (∼29,000) with discordant methylation. Demethylation of probes in the buffy coat compared to derived cell lines was more common and was prevalent in shelf and open sea regions. Conclusion: Buffy coat is representative of methylation patterns in WBC types in normal pregnancy. The differential methylations are consistent with perturbations during isolation of constituent cells and likely originate in vitro due to the physical stress during cell separation and are of no physiological relevance. These findings help the interpretation of DNA methylation profiling in pregnancy and numerous other conditions.

The association of microhematuria with mesangial hypercellularity, endocapillary hypercellularity, crescent score and renal outcomes in immunoglobulin A nephropathy

BACKGROUND

Microhematuria is common in immunoglobulin A nephropathy (IgAN). However, current prognostication is based on proteinuria and mesangial hypercellularity, endocapillary hypercellularity, segmental sclerosis, tubulointerstitial fibrosis and crescent (MEST-C) scores.

METHODS

In this retrospective study, we evaluated whether MEST-C score components are associated with the presence of microhematuria at biopsy and whether the degree of microhematuria during follow-up is associated with change in estimated glomerular filtration rate (eGFR), after adjusting for clinical and histological parameters. We identified 125 patients with biopsy-proven IgAN and MEST-C scoring who were not on immunosuppressive therapy at biopsy. Microhematuria was defined as ≥3 red blood cells (RBCs)/high-power field (hpf).

RESULTS

Of the 125 patients, 97 had microhematuria at baseline and were more likely to have M1, E1 and C ≥ 1 lesions (P < 0.05 for all) compared with patients without microhematuria. Of the 125 patients, 72 had follow-up data available. An increase in the degree of microhematuria was significantly associated with an eGFR decline of -0.81 mL/min/1.73 m2 [95% confidence interval (CI) -1.44 to -0.19, P = 0.01], after adjusting for follow-up time, proteinuria and T score. Severe microhematuria (≥21 RBCs/hpf) was associated with an even larger decline in eGFR (-3.99 mL/min/1.73 m2; 95% CI -6.9411 to -1.0552, P = 0.008), after similar adjustments.

CONCLUSION

Degree of microhematuria during follow-up is an independent predictor of eGFR decline after adjusting for clinical and histological parameters. Therefore, monitoring the degree of microhematuria as well as proteinuria is important when evaluating patients with IgAN. Additional studies using improvement in microhematuria as a primary surrogate outcome are needed.

How accurate are citations of frequently cited papers in biomedical literature?

Citations are an important, but often overlooked, part of every scientific paper. They allow the reader to trace the flow of evidence, serving as a gateway to relevant literature. Most scientists are aware of citations' errors, but few appreciate the prevalence of these problems. The purpose of the present study was to examine how often frequently cited papers in biomedical scientific literature are cited inaccurately. The study included an active participation of the first authors of included papers; to first-hand verify the citations accuracy. Findings from feasibility study, where we reviewed 1540 articles containing 2526 citations of 14 most cited articles in which the authors were affiliated with the Faculty of Medicine University of Belgrade, were further evaluated for external confirmation in an independent verification set of articles. Verification set included 4912 citations identified in 2995 articles that cited 13 most cited articles published by authors affiliated with the Mayo Clinic Division of Nephrology and Hypertension. A citation was defined as being accurate if the cited article supported or was in accordance with the statement by citing authors. At least one inaccurate citation was found in 11 and 15% of articles in the feasibility study and verification set, respectively, suggesting that inaccurate citations are common in biomedical literature. The most common problem was the citation of nonexistent findings (38.4%), followed by an incorrect interpretation of findings (15.4%). One-fifth of inaccurate citations were due to chains of inaccurate citations. Based on these findings, several actions to reduce citation inaccuracies have been proposed.

COVID-19 and Sex Differences: Mechanisms and Biomarkers

Men are consistently overrepresented in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, and coronavirus disease 2019 (COVID-19) severe outcomes, including higher fatality rates. These differences are likely due to gender-specific behaviors, genetic and hormonal factors, and sex differences in biological pathways related to SARS-CoV-2 infection. Several social, behavioral, and comorbid factors are implicated in the generally worse outcomes in men compared with women. Underlying biological sex differences and their effects on COVID-19 outcomes, however, have received less attention. The present review summarizes the available literature regarding proposed molecular and cellular markers of COVID-19 infection, their associations with health outcomes, and any reported modification by sex. Biological sex differences characterized by such biomarkers exist within healthy populations and also differ with age- and sex-specific conditions, such as pregnancy and menopause. In the context of COVID-19, descriptive biomarker levels are often reported by sex, but data pertaining to the effect of patient sex on the relationship between biomarkers and COVID-19 disease severity/outcomes are scarce. Such biomarkers may offer plausible explanations for the worse COVID-19 outcomes seen in men. There is the need for larger studies with sex-specific reporting and robust analyses to elucidate how sex modifies cellular and molecular pathways associated with SARS-CoV-2. This will improve interpretation of biomarkers and clinical management of COVID-19 patients by facilitating a personalized medical approach to risk stratification, prevention, and treatment.

The prognostic importance of serum sodium levels at hospital discharge and one-year mortality among hospitalized patients

BACKGROUND

The optimal range of serum sodium at hospital discharge is unclear. Our objective was to assess the one-year mortality based on discharge serum sodium in hospitalized patients.

METHODS

We analyzed a cohort of hospitalized adult patients between 2011 and 2013 who survived hospital admission at a tertiary referral hospital. We categorized discharge serum sodium into five groups; ≤132, 133-137, 138-142, 143-147, and ≥148 mEq/L. We assessed one-year mortality risk after hospital discharge based on discharge serum sodium, using discharge sodium of 138-142 mEq/L as the reference group.

RESULTS

Of 55 901 eligible patients, 4.9%, 29.8%, 56.1%, 8.9%, 0.3% had serum sodium of ≤132, 133-137, 138-142, 143-147, and ≥148 mEq/L, respectively. We observed a U-shaped association between discharge serum sodium and one-year mortality, with nadir mortality in discharge serum sodium of 138-142 mEq/L. When adjusting for potential confounders, including admission serum sodium, one-year mortality was significantly higher in both discharge serum sodium ≤137 and ≥143 mEq/L, compared with discharge serum sodium of 138-142 mEq/L. The mortality risk was the most prominent in elevated discharge serum sodium of ≥148 mEq/L (HR 3.86; 95% CI 3.05-4.88), exceeding the risk associated with low discharge serum sodium of ≤132 mEq/L (HR 1.43; 95% CI 1.30-1.57).

CONCLUSION

The optimal range of serum sodium at discharge was 138-142 mEq/L. Both hypernatremia and hyponatremia at discharge were associated with higher one-year mortality. The impact on higher one-year mortality was more prominent in hypernatremia than hyponatremia.

Acute Interstitial Nephritis and Checkpoint Inhibitor Therapy

Background

The objective of this case cohort study was to describe our experience in the care of patients with immune checkpoint inhibitor–related acute interstitial nephritis (ICI-AIN) including rechallenge.

Methods

A descriptive case series of patients that received an ICI and had an AKI (defined as a ≥1.5-fold increase in serum creatinine) as an immune-related adverse event (irAE), with biopsy-proven or clinically suspected ICI-AIN from January 1, 2014 to December 1, 2018 at Mayo Clinic, Rochester. We studied details regarding diagnosis, clinical course, management, and outcomes of rechallenge of immunotherapy. Complete response (CR) was defined as return of kidney function back to baseline or <0.3 mg/dl above baseline creatinine; partial response (PR) was defined as creatinine >0.3 mg/dl from baseline, but less than twofold above the baseline by the end of steroid course.

Results

A total of 14 cases of biopsy-proven (35%) or clinically suspected (65%) ICI-AIN was identified. All patients had their ICI withheld and 12 patients received steroids. Steroid regimens were highly variable. The starting equivalent dose of prednisone was higher in those that had a CR versus a PR (median 0.77 mg/kg versus 0.66 mg/kg). Proton pump inhibitors (PPIs) were used in 11 patients and were stopped in eight (73%) patients at the time of the AKI event. A CR was seen in five (63%) of the eight patients who discontinued PPIs. Rechallenge was attempted in four of the 14 patients: three were successful with no recurrence of AKI, but one patient had recurrent AKI and fatal pneumonitis.

Conclusions

Careful review, withholding ICI and concomitant known AIN-inducing medications, along with prompt initial steroid management were the key in complete renal kidney recovery. A kidney biopsy should be strongly considered. Rechallenge of immunotherapy after a kidney irAE, although challenging, is possible and would need careful evaluation on an individual basis.

Podcast

This article contains a podcast at https://www.asn-online.org/media/podcast/K360/2020_01_30_KID0000152019.mp3

Efficacy and safety profile of sunitinib as a first line treatment for advanced/metastatic clear-cell renal cell carcinoma: Pooled analysis of randomized controlled trials

e16067

Background: Metastatic clear-cell renal cell carcinoma (RCC) is largely incurable, and its treatment remains challenging. Sunitinib, a tyrosine kinase inhibitor, is one of the current standard-of-care options for treatment-naïve patients with metastatic RCC. Despite the proven efficacy of Sunitinib, prolonged treatment with some tyrosine kinase inhibitors (TKIs) has been associated with significant adverse events (AEs). Therefore, we aimed to calculate the exact efficacy in addition to the prevalence of all AEs of Sunitinib in a pooled analysis from all available randomized controlled trials (RCTs). Methods: A comprehensive electronic database search was conducted for all RCTs comparing the clinical outcomes and adverse events of Sunitinib versus all other available treatments for treatment-naïve advanced/metastatic clear-cell renal cell carcinoma. We then calculated the pooled outcomes and prevalence of the most common reported side effects of Sunitinib. All statistical analyses were performed using R Statistical Software v3.4.0 (R Foundation, Vienna, Austria). Results: We included 8 RCTs, with a total of 4106 patients. The mean age was62, with 66.44% males.The efficacy of Sunitinib was reported as 3 main outcomes: Median progression free survival at 10.73 [7.76, 13.7] months, median overall survival at 23.28 [16.74, 29.81] months and the estimated objective response rate at 25[13, 37] %. Any grade AEs were reported in 72% of patients with the following frequencies: fatigue 44%, diarrhea 38%, nausea 31%, hand-foot syndrome 30%, hypertension 27%, dysgeusia 25%, hypothyroidism25%, constipation 20%, stomatitis 20%, inflammation of the mucosa 18%, dyspepsia 16%, vomiting 14%, rash 12%, asthenia 11%, and epistaxis10%.Grade 3&4 (severe) AEs were reported in 52% of patients with the following frequencies: hypertension 9%, fatigue 8%, hand-foot syndrome 5%, asthenia 5%, diarrhea 4%, and inflammation of the mucosa 2%. Conclusions: Despite Sunitinib being one of the current standard treatments for patients with metastatic/advanced clear-cell RCC, with well-described efficacy, its safety profile is still concerning with a significant prevalence of reported grade 3-4 AEs of 52% of the treated patients in the included RCTs. These findings underscore the importance of the emergence of newer drugs and treatment plans for patients with metastatic RCC, not only to achieve similar or better clinical outcomes but also to decrease the percentage of grade 3-4 AEs.

Factors associated with short recurrence-free survival in completely resected colon cancer

Background: Several factors could affect disease recurrence in surgically resected colon cancer. While the role of certain factors such as cancer stage and grade is well established, the role of other factors (e.g., histological subtypes) is yet to be determined.

Objective:Therefore, we conducted a study to evaluate the impact of several factors in recurrence-free survival (RFS) in patients who were disease free following surgical resection of the colon cancer.

Design/Methods: Data were collected for patients with Stage I–III colon cancer who underwent complete surgical resection of the tumor between January 2010 and December 2015 in our institution. A total of 90 subjects met the inclusion criteria and were included in the study. The following factors were collected at the time of surgical resection of the colonic tumor: patient’s age, gender, colon cancer stage, grade and histological subtype, body mass index, hemoglobin A1c, and smoking history.

Results: A total of 28 patients (31%) developed recurrence and had a mean follow-up time of 19.8 months (range: 2–54.4 months). Median RFS was 54.4 months with a 5-year RFS of 49%. Advanced colonic cancer stage and mucinous histological subtype were associated with shorter RFS with an HR of 2.37, 95% CI = 1.38–4.06, and 95% CI = 1.02–5.90, respectively. Current smokers or those who quit less than 15 years earlier tended to have worse RFS with an HR of 2.47, 95% CI = 0.98–6.27.

Conclusion: Advanced colon cancer stage and mucinous histological subtype are independent risk factors for cancer recurrence and shorter RFS in completely resected colonic tumor.

Surveying Resident and Faculty Physician Knowledge, Attitudes, and Experiences in Response to Public Lead Contamination

Environmental health crises can appear anywhere and without warning. After research revealed a significant incidence of elevated pediatric blood lead levels following a water source change, Genesee County declared a public health emergency in Flint, Michigan. Hospital patients and family members began approaching Hurley Medical Center's physicians with questions regarding the health implications of the lead contamination. Many of the physicians voiced concerns about responding appropriately to patient needs and increasing demands for information. As a result, a Hurley research team decided to conduct an informal survey across training programs to determine the need for added education.Because of heightened patient anxiety, it was necessary for the timeline to progress quickly. In creating the survey, the team's objective was to assess resident and faculty physician knowledge, attitudes, and experiences concerning lead contamination. The results revealed a critical need for supplementary training. Therefore, Hurley embarked on an education campaign for its graduate medical education programs, benefiting physicians and patients alike.Patient and physician needs may change drastically following an environmental health emergency. It is the duty of medical centers to ensure their clinicians are well equipped to confront such threats. As prompt treatment is often a key to positive health outcomes, the authors stress the importance of acting quickly and suggest conducting informal surveys to identify gaps in physician knowledge. Likewise, the authors encourage medical educators nationwide to examine their environmental health curricula. It appears lead-contaminated water is not just a Flint problem but may have far-reaching implications for many cities.