Structure and mechanism of homoserine kinase: prototype for the GHMP kinase superfamily

BACKGROUND

Homoserine kinase (HSK) catalyzes an important step in the threonine biosynthesis pathway. It belongs to a large yet unique class of small metabolite kinases, the GHMP kinase superfamily. Members in the GHMP superfamily participate in several essential metabolic pathways, such as amino acid biosynthesis, galactose metabolism, and the mevalonate pathway.

RESULTS

The crystal structure of HSK and its complex with ADP reveal a novel nucleotide binding fold. The N-terminal domain contains an unusual left-handed betaalphabeta unit, while the C-terminal domain has a central alpha-beta plait fold with an insertion of four helices. The phosphate binding loop in HSK is distinct from the classical P loops found in many ATP/GTP binding proteins. The bound ADP molecule adopts a rare syn conformation and is in the opposite orientation from those bound to the P loop-containing proteins. Inspection of the substrate binding cavity indicates several amino acid residues that are likely to be involved in substrate binding and catalysis.

CONCLUSIONS

The crystal structure of HSK is the first representative in the GHMP superfamily to have determined structure. It provides insight into the structure and nucleotide binding mechanism of not only the HSK family but also a variety of enzymes in the GHMP superfamily. Such enzymes include galactokinases, mevalonate kinases, phosphomevalonate kinases, mevalonate pyrophosphate decarboxylases, and several proteins of yet unknown functions.

Incidence Rates, Household Infection Risk, and Clinical Characteristics of SARS-CoV-2 Infection Among Children and Adults in Utah and New York City, New York

IMPORTANCE

Data about the risk of SARS-CoV-2 infection among children compared with adults are needed to inform COVID-19 risk communication and prevention strategies, including COVID-19 vaccination policies for children.

OBJECTIVE

To compare incidence rates and clinical characteristics of SARS-CoV-2 infection among adults and children and estimated household infection risks within a prospective household cohort.

DESIGN, SETTING, AND PARTICIPANTS

Households with at least 1 child aged 0 to 17 years in selected counties in Utah and New York City, New York, were eligible for enrollment. From September 2020 through April 2021, participants self-collected midturbinate nasal swabs for reverse transcription-polymerase chain reaction testing for SARS-CoV-2 and responded to symptom questionnaires each week. Participants also self-collected additional respiratory specimens with onset of COVID-19-like illness. For children unable to self-collect respiratory specimens, an adult caregiver collected the specimens.

MAIN OUTCOMES AND MEASURES

The primary outcome was incident cases of any SARS-CoV-2 infection, including asymptomatic and symptomatic infections. Additional measures were the asymptomatic fraction of infection calculated by dividing incidence rates of asymptomatic infection by rates of any infection, clinical characteristics of infection, and household infection risks. Primary outcomes were compared by participant age group.

RESULTS

A total of 1236 participants in 310 households participated in surveillance, including 176 participants (14%) who were aged 0 to 4 years, 313 (25%) aged 5 to 11 years, 163 (13%) aged 12 to 17 years, and 584 (47%) 18 years or older. Overall incidence rates of SARS-CoV-2 infection were 3.8 (95% CI, 2.4-5.9) and 7.7 (95% CI, 4.1-14.5) per 1000 person-weeks among the Utah and New York City cohorts, respectively. Site-adjusted incidence rates per 1000 person-weeks were similar by age group: 6.3 (95% CI, 3.6-11.0) for children 0 to 4 years, 4.4 (95% CI, 2.5-7.5) for children 5 to 11 years, 6.0 (95% CI, 3.0-11.7) for children 12 to 17 years, and 5.1 (95% CI, 3.3-7.8) for adults (≥18 years). The asymptomatic fractions of infection by age group were 52%, 50%, 45%, and 12% among individuals aged 0 to 4 years, 5 to 11 years, 12 to 17 years, and 18 years or older, respectively. Among 40 households with 1 or more SARS-CoV-2 infections, the mean risk of SARS-CoV-2 infection among all enrolled household members was 52% (range, 11%-100%), with higher risks in New York City compared with Utah (80% [95% CI, 64%-91%] vs 44% [95% CI, 36%-53%]; P < .001).

CONCLUSIONS AND RELEVANCE

In this study, children had similar incidence rates of SARS-CoV-2 infection compared with adults, but a larger proportion of infections among children were asymptomatic.

Archaeal shikimate kinase, a new member of the GHMP-kinase family

Shikimate kinase (EC 2.7.1.71) is a committed enzyme in the seven-step biosynthesis of chorismate, a major precursor of aromatic amino acids and many other aromatic compounds. Genes for all enzymes of the chorismate pathway except shikimate kinase are found in archaeal genomes by sequence homology to their bacterial counterparts. In this study, a conserved archaeal gene (gi1500322 in Methanococcus jannaschii) was identified as the best candidate for the missing shikimate kinase gene by the analysis of chromosomal clustering of chorismate biosynthetic genes. The encoded hypothetical protein, with no sequence similarity to bacterial and eukaryotic shikimate kinases, is distantly related to homoserine kinases (EC 2.7.1.39) of the GHMP-kinase superfamily. The latter functionality in M. jannaschii is assigned to another gene (gi591748), in agreement with sequence similarity and chromosomal clustering analysis. Both archaeal proteins, overexpressed in Escherichia coli and purified to homogeneity, displayed activity of the predicted type, with steady-state kinetic parameters similar to those of the corresponding bacterial kinases: K(m,shikimate) = 414 +/- 33 microM, K(m,ATP) = 48 +/- 4 microM, and k(cat) = 57 +/- 2 s(-1) for the predicted shikimate kinase and K(m,homoserine) = 188 +/- 37 microM, K(m,ATP) = 101 +/- 7 microM, and k(cat) = 28 +/- 1 s(-1) for the homoserine kinase. No overlapping activity could be detected between shikimate kinase and homoserine kinase, both revealing a >1,000-fold preference for their own specific substrates. The case of archaeal shikimate kinase illustrates the efficacy of techniques based on reconstruction of metabolism from genomic data and analysis of gene clustering on chromosomes in finding missing genes.

Structural basis for the catalysis and substrate specificity of homoserine kinase

Homoserine kinase (HSK), the fourth enzyme in the aspartate pathway of amino acid biosynthesis, catalyzes the phosphorylation of L-homoserine (Hse) to L-homoserine phosphate, an intermediate in the production of L-threonine, L-isoleucine, and in higher plants, L-methionine. The high-resolution structures of Methanococcus jannaschii HSK ternary complexes with its amino acid substrate and ATP analogues have been determined by X-ray crystallography. These structures reveal the structural determinants of the tight and highly specific binding of Hse, which is coupled with local conformational changes that enforce the sequestration of the substrate. The delta-hydroxyl group of bound Hse is only 3.4 A away from the gamma-phosphate of the bound nucleotide, poised for the in-line attack at the gamma-phosphorus. The bound nucleotides are flexible at the triphosphate tail. Nevertheless, a Mg(2+) was located in one of the complexes that binds between the beta- and gamma-phosphates of the nucleotide with good ligand geometry and is coordinated by the side chain of Glu130. No strong nucleophile (base) can be located near the phosphoryl acceptor hydroxyl group. Therefore, we propose that the catalytic mechanism of HSK does not involve a catalytic base for activating the phosphoryl acceptor hydroxyl but instead is mediated via a transition state stabilization mechanism.

Distribution and molecular analysis of Lyme disease spirochetes, Borrelia burgdorferi, isolated from ticks throughout California

Previous studies describing the occurrence and molecular characteristics of Lyme disease spirochetes, Borrelia burgdorferi, from California have been restricted primarily to isolates obtained from the north coastal region of this large and ecologically diverse state. Our objective was to look for and examine B. burdorferi organisms isolated from Ixodes pacificus ticks collected from numerous regions spanning most parts of California where this tick is found. Thirty-one isolates of B. burgdorferi were examined from individual or pooled I. pacificus ticks collected from 25 counties throughout the state. One isolate was obtained from ticks collected at Wawona Campground in Yosemite National Park, documenting the occurrence of the Lyme disease spirochete in an area of intensive human recreational use. One isolate from an Ixodes neotomae tick from an additional county was also examined. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis, immunoblot analysis, agarose gel electrophoresis, Southern blot analysis, and the polymerase chain reaction were used to examine the molecular and genetic determinants of these uncloned, low-passage-number isolates. All of the isolates were identified as B. burgdorferi by their protein profiles and reactivities with monoclonal and polyclonal antibodies, and all the isolates were typed by the polymerase chain reaction as North American-type spirochetes (B. burgdorferi sensu stricto). Although products of the ospAB locus were identified in protein analyses in all of the isolates, several isolates contained deleted forms of this locus that would result in the expression of chimeric OspA-OspB proteins. The analysis of OspC demonstrated that this protein was widely conserved among the isolates but was also quite variable in its molecular mass and the amount of it that was expressed.

Attitudes Toward COVID-19 Illness and COVID-19 Vaccination among Pregnant Women: A Cross-Sectional Multicenter Study during August-December 2020

OBJECTIVE

The aim of the study was to evaluate pregnant women's attitudes toward COVID-19 illness and vaccination and identify factors associated with vaccine acceptability.

STUDY DESIGN

This was a cross-sectional survey among pregnant women enrolled in a prospective COVID-19 cohort study in Salt Lake City, UT, Birmingham, AL, and New York, NY, from August 9 to December 10, 2020. Women were eligible if they were 18 to 50 years old and <28 weeks of gestation. Upon enrollment, women completed surveys regarding concerns about COVID-19 illness and likelihood of getting COVID-19 vaccine if one were available during pregnancy. Vaccine acceptability was defined as a response of "very likely" or "somewhat likely" on a 4-point Likert scale. Factors associated with vaccine acceptability were assessed with multivariable logistic regression.

RESULTS

Of 939 pregnant women eligible for the main cohort study, 915 (97%) consented to participate. Among these 915 women, 39% self-identified as White, 23% Black, 33% Hispanic, and 4% Other. Sixty-two percent received an influenza vaccine last season. Seventy-two percent worried about getting sick with COVID-19. If they were to get sick, 92% worried about harm to their pregnancy and 80% about harm to themselves. Only 41% reported they would get a vaccine. Of women who were unlikely to get vaccinated, the most frequently cited concern was vaccine safety for their pregnancy (82%). Non-Hispanic Black and Hispanic women had lower odds of accepting a vaccine compared with non-Hispanic White women (adjusted odds ratios [aOR] 0.4, 95% CI 0.2-0.6 for both). Receipt of influenza vaccine during the previous season was associated with higher odds of vaccine acceptability (aOR 2.1, 95% CI 1.5-3.0).

CONCLUSION

Although most pregnant women worried about COVID-19 illness, <50% were willing to get vaccinated during pregnancy. Racial and ethnic disparities in plans to accept COVID-19 vaccine highlight the need to prioritize strategies to address perceived barriers among groups at high risk for COVID-19.

KEY POINTS

· Less than half of pregnant patients stated they would get a COVID-19 vaccine.. · Protecting their baby was the most common reason for acceptance and refusal of the COVID-19 vaccine.. · Patients of minority race/ethnicity and those without prior influenza vaccination were less likely to accept the COVID-19 vaccine..

Observations of the global epidemiology of COVID-19 from the prepandemic period using web-based surveillance: a cross-sectional analysis

Background

Scant data are available about global patterns of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spread and global epidemiology of early confirmed cases of COVID-19 outside mainland China. We describe the global spread of SARS-CoV-2 and characteristics of COVID-19 cases and clusters before the characterisation of COVID-19 as a pandemic.

Methods

Cases of COVID-19 reported between Dec 31, 2019, and March 10, 2020 (ie, the prepandemic period), were identified daily from official websites, press releases, press conference transcripts, and social media feeds of national ministries of health or other government agencies. Case characteristics, travel history, and exposures to other cases were abstracted. Countries with at least one case were classified as affected. Early cases were defined as those among the first 100 cases reported from each country. Later cases were defined as those after the first 100 cases. We analysed reported travel to affected countries among the first case reported from each country outside mainland China, demographic and exposure characteristics among cases with age or sex information, and cluster frequencies and sizes by transmission settings.

Findings

Among the first case reported from each of 99 affected countries outside of mainland China, 75 (76%) had recent travel to affected countries; 60 (61%) had travelled to China, Italy, or Iran. Among 1200 cases with age or sex information, 874 (73%) were early cases. Among 762 early cases with age information, the median age was 51 years (IQR 35–63); 25 (3%) of 762 early cases occurred in children younger than 18 years. Overall, 21 (2%) of 1200 cases were in health-care workers and none were in pregnant women. 101 clusters were identified, of which the most commonly identified transmission setting was households (76 [75%]; mean 2·6 cases per cluster [range 2–7]), followed by non-health-care occupational settings (14 [14%]; mean 4·3 cases per cluster [2–14]), and community gatherings (11 [11%]; mean 14·2 cases per cluster [4–36]).

Interpretation

Cases with travel links to China, Italy, or Iran accounted for almost two-thirds of the first reported COVID-19 cases from affected countries. Among cases with age information available, most were among adults aged 18 years and older. Although there were many clusters of household transmission among early cases, clusters in occupational or community settings tended to be larger, supporting a possible role for physical distancing to slow the progression of SARS-CoV-2 spread.

Funding

None.

Primary urethral carcinoma: A Surveillance, Epidemiology, and End Results data analysis identifying predictors of cancer-specific survival

Objectives

Primary urethral carcinoma (PUC) is rare, accounting for <1% of genitourinary malignancies. Current knowledge regarding is founded upon tertiary care centers reporting their experiences. We aim to identify factors predictive of outcomes using a nationwide registry database.

Materials and Methods

The Surveillance, Epidemiology, and End Results-18 registries database was queried for cases of PUC ranging between 2004 and 2010. To identify PUC cases, ICD-O site code C68.0 was used as a filter, hence identifying PUC with histologic subtypes including urothelial carcinoma (UC), squamous cell carcinoma (SCC), and adenocarcinoma (AC). Tumor characteristics were compared using log-rank analysis, and survival outcomes were compared using Cox proportional hazards models.

Results

A total of 419 PUC cases were identified, 250 (59.7%) male and 169 (40.3%) female patients. The most common histology in men was UC (134, 53.6%), followed by SCC (87, 34.8%) and AC (29, 11.6%). The most common histology in women was AC (79, 46.7%), followed by SCC (43, 25.4%) and UC (42, 24.9%). Log-rank analysis illustrated significant difference in cancer-specific survival (CSS) for T-stage, N-stage, M-stage, and stage of PUC with all histological variants combined (P < 0.001). Multivariate Cox proportional hazards model demonstrated that stage and age were significant for survival, with a risk ratio of 1.033 (95% confidence interval [CI], 1.020-1.046)/year of increased age (P < 0.001) and 3.71 (95% CI, 2.72-5.05) for patients with regional or distant spread.

Conclusions

Knowledge of patient and tumor characteristics that influences survival is paramount in dictating management. The present study illustrates that age and stage are factors significantly associated with CSS in PUC.

Multicenter evaluation of the MicroScan Rapid Gram-Negative Identification Type 3 Panel

The accuracy and performance of the revised MicroScan Rapid Gram-Negative Identification Type 3 Panel (Dade MicroScan Inc., West Sacramento, Calif.) were examined in a multicenter evaluation. The revised panel database includes data for 119 taxa covering a total of 150 species, with data for 12 new species added. Testing was performed in three phases: the efficacy, challenge, and reproducibility testing phases. A total of 405 fresh and stock gram-negative isolates comprising 54 species were tested in the efficacy phase; 96.8% of these species were identified correctly in comparison to the identification obtained either with the API 20E system (bioMérieux Vitek, Hazelwood, Mo.) or by the conventional tube method. The number of correctly identified isolates in the challenge phase, including new species added to the database, was 221 of 247, or 89.5%, in comparison to the number correctly identified by the conventional tube method. A total of 465 isolates were examined for intra- and interlaboratory identification reproducibility and gave an agreement of 464 of 465, or 99.8%. The overall reproducibility of each individual identification test or substrate was 14,373 of 14,384, or 99.9%. The new Rapid Gram-Negative Identification Type 3 Panel gave accurate and highly reproducible results in this multiple-laboratory evaluation.

Clinical Epidemiology and Outcomes of Pediatric Musculoskeletal Infections

OBJECTIVES

To understand the epidemiology of acute hematogenous osteomyelitis and septic arthritis, including clinical and demographic features, microbiology, treatment approaches, treatment-associated complications, and outcomes.

STUDY DESIGN

Retrospective cohort study of 453 children with acute hematogenous osteomyelitis and/or septic arthritis from 2009 to 2015.

RESULTS

Among the 453 patients, 218 (48%) had acute hematogenous osteomyelitis, 132 (29%) had septic arthritis, and 103 (23%) had concurrent acute hematogenous osteomyelitis/septic arthritis. Treatment failure/recurrent infection occurred in 41 patients (9%). Patients with concurrent acute hematogenous osteomyelitis/septic arthritis had longer hospital stays, longer duration of antibiotic therapy, and were more likely to have prolonged bacteremia and require intensive care. Staphylococcus aureus was identified in 228 (51%) patients, of which 114 (50%) were methicillin-resistant S aureus. Compared with septic arthritis, acute hematogenous osteomyelitis and concurrent acute hematogenous osteomyelitis/septic arthritis were associated with higher odds of treatment failure (OR, 8.19; 95% CI, 2.02-33.21 [P = .003]; and OR, 14.43; 95% CI, 3.39-61.37 [P < .001], respectively). The need for more than 1 surgical procedure was also associated with higher odds of treatment failure (OR, 2.98; 95% CI, 1.18-7.52; P = .021). Early change to oral antibiotic therapy was not associated with treatment failure (OR, 0.64; 95% CI, 0.24-1.74; P = .386). Most (73%) medically attended treatment complications occurred while on parenteral therapy.

CONCLUSIONS

Musculoskeletal infections are challenging pediatric infections. S aureus remains the most common pathogen, with methicillin-resistant S aureus accounting for 25% of all cases. Concurrent acute hematogenous osteomyelitis/septic arthritis is associated with more severe disease and worse outcomes. Fewer treatment-related complications occurred while on oral therapy. Early transition to oral therapy was not associated with treatment failure.

Prevalence of Trichomonas vaginalis Infection Among US Males, 2013-2016

Background

Trichomoniasis results from adhesion of Trichomonas vaginalis to the mucous membrane of the urethra or vagina. It has been estimated to have a higher incidence rate than both gonorrhea and chlamydia combined. Although females can experience both clinical symptoms and obstetrical complications, male infections are largely asymptomatic and often unreported. We aim to estimate the prevalence of trichomoniasis in US males using the National Health and Nutrition Examination Survey (NHANES) database.

Methods

The NHANES database was queried for all men aged 18-59 years during the years 2013-2016. During these years, the survey included urine testing for trichomoniasis using transcription-mediated amplification. Information was also obtained regarding patient demographics and other sexually transmitted infections.

Results

Overall, 0.49% of men aged 18-59 years tested positive for trichomoniasis. The highest rate was seen in black men (3.6%). There was no significant association with trichomoniasis and age. Higher rates of infection were seen in smokers, those with herpes simplex virus type 2 (HSV-2) infection, men who had sex at an early age, those with less condom usage, and those with more lifetime sexual partners.

Conclusion

The rates of trichomonas infection in US males are lower than in women. Infections are strongly associated with black males, HSV-2 infection, and other factors known to increase rates of sexually transmitted infection. This information may be helpful for counseling, screening, and management of patients.

Incidence, Clinical Characteristics, and Risk Factors of SARS-CoV-2 Infection among Pregnant Individuals in the United States

BACKGROUND

Data about the risk of SARS-CoV-2 infection among pregnant individuals are needed to inform infection prevention guidance and counseling for this population.

METHODS

We prospectively followed a cohort of pregnant individuals during August 2020-March 2021 at three U.S. sites. The three primary outcomes were incidence rates of any SARS-CoV-2 infection, symptomatic infection, and asymptomatic infection, during pregnancy during periods of SARS-CoV-2 circulation. Participants self-collected weekly mid-turbinate nasal swabs for SARS-CoV-2 RT-PCR testing, completed weekly illness symptom questionnaires, and submitted additional swabs with COVID-19-like symptoms. An overall SARS-CoV-2 infection incidence rate weighted by population counts of women of reproductive age in each state was calculated.

RESULTS

Among 1098 pregnant individuals followed for a mean of 10 weeks, nine percent (99/1098) had SARS-CoV-2 infections during the study. Population weighted incidence rates of SARS-CoV-2 infection were 10.0 per 1,000 (95% confidence interval [CI] 5.7-14.3) person-weeks for any infection, 5.7 per 1,000 (95% CI 1.7-9.7) for symptomatic infections, and 3.5 per 1,000 (95% CI 0-7.1) for asymptomatic infections. Among 96 participants with SARS-CoV-2 infection and symptom data, the most common symptoms were nasal congestion (72%), cough (64%), headache (59%), and change in taste or smell (54%); 28% had measured or subjective fever. The median symptom duration was 10 days (IQR6-16 days).

CONCLUSION

Pregnant individuals had a 1% risk of SARS-CoV-2 infection per week. Study findings provide information about SARS-CoV-2 infection risk during pregnancy to inform counseling for pregnant individuals about infection prevention practices, including COVID-19 vaccination.

Renal cell carcinoma and brain metastasis: Questioning the dogma of role for cytoreductive nephrectomy

INTRODUCTION

Renal cell carcinoma (RCC) brain metastasis is generally viewed as poor prognostic features and often excludes patients from cytoreductive nephrectomy or participation in clinical trials. We aim to evaluate patients presenting with brain metastasis and their outcomes.

METHODS

Surveillance Epidemiology and End Results-18 registries database was queried for all patients with metastatic RCC from 2010 to 2014. Patients with renal cancer as their only malignancy were included. Information was available for metastatic disease to bone, liver, lung, and brain. Patients were then further stratified into those with isolated brain metastases and those with additional metastasis to other sites as well. Overall survival was compared between groups using logrank analysis.

RESULTS

A total of 6,667 patients were identified with metastatic RCC. Among them, 775 (12.1%) had brain metastasis at time of diagnosis. Of these patients with brain metastasis, 152 (20.4%) had isolated brain metastasis. Only 23.8% of all patients with brain metastasis underwent cytoreductive nephrectomy, compared to 40.8% of patients with isolated brain metastasis. Patients with brain and other metastasis and brain metastasis only treated by cytoreductive nephrectomy exhibited a median survival of 11 and 33 months, respectively. Those patients who did not undergo cytoreductive nephrectomy experienced a median survival of 4 and 5 months, respectively.

CONCLUSION

It appears that selected patients with brain metastasis may experience durable long-term survival. This information may be beneficial for patient counseling, surgical planning, and consideration for inclusion in clinical trials.

Clinical and Patient-reported Outcomes of 1-sided Anterior Urethroplasty for Long-segment or Panurethral Strictures

OBJECTIVE

To evaluate clinical and patient-reported urinary and sexual outcomes after a long-segment stricture repair using the 1-sided urethral dissection, penile invagination, and dorsal buccal mucosa graft onlay technique described by Kulkarni et al.

METHODS

Patients from 4 institutions after single-stage repairs for long-segment urethral strictures (>8 cm) from January 2002 to April 2016 were reviewed. Technique described by Kulkarni et al was used in all cases. Clinical outcomes included uroflowmetry (Qmax) and post-void residuals. Patient-reported outcome measures included International Prostate Symptom Score survey, Sexual Health Inventory for Men, Male Sexual Health Questionnaire, and Global Response Assessment questionnaire to measure voiding, sexual, ejaculatory symptoms, and overall improvement, respectively.

RESULTS

Seventy-three patients with a minimum of 12 months' follow-up were included. The mean age and stricture length were 56 (21-80) years and 13.6 (8-21) cm, respectively. At a mean follow-up of 44 (12-162) months, 9 of 73 (12%) strictures recurred. The mean baseline International Prostate Symptom Score of 23 (7-24) decreased to 10 (1-17) on follow-up (P <.001). Eight of 42 patients (21.4%) reported an increase, and 6 of 42 patients (14.3%) decreased in Sexual Health Inventory for Men following urethroplasty. Ejaculatory function on Male Sexual Health Questionnaire improved after urethroplasty from 8 preoperatively to 11 postoperatively (P <.004). All patients reported improvement after urethroplasty on Global Response Assessment questionnaire. Post-void dribbling and chordee occurred in 45% and 25% of patients, respectively.

CONCLUSION

Durable patency in most patients is demonstrated in this study. PROMs indicate an improvement in urinary function and moderate effect on sexual function. Transient penile chordee was evident in 25% of patients.

Comparison of survival for partial vs. radical nephrectomy in young patients with T1a renal cell carcinoma treated at commission on cancer-accredited facilities and influence of comorbidities on treatment choice

PURPOSE

There is a paucity of data comparing effects of partial nephrectomy (PN) vs. radical nephrectomy (RN) on overall survival in young patients. In this study, the National Cancer Database was used to evaluate the survival outcomes of those treated with PN and RN, and influence of comorbidities on surgical treatment (PN vs. RN) in young patients while accounting for Charlson-Deyo Comorbidity Score (CDCS).

MATERIALS AND METHODS

Patients between 20 and 44 years old (n = 9,849) surgically treated for pT1a renal cell carcinoma between 2004 and 2013 were identified from the National Cancer Database. Kaplan-Meier log-rank analysis and Cox proportional hazards model were performed to compare overall survival and calculate the hazard ratio between those undergoing RN and PN. Binary logistic regression was used to calculate odds ratios for receiving RN compared to PN. The effect measures in all models were adjusted for potential confounding factors.

RESULTS

After adjusting for comorbidities, PN offered an overall survival advantage over RN (P<0.001, hazard ratio = 0.464, 95% CI: 0.359-0.601) at a mean follow-up of 48.4 months (0-130.96), including young patients with no comorbidities (P<0.001). Compared to those with a CDCS = 0, patients were more likely to be treated with RN if they had a CDCS>1 (odds ratios = 2.049, 95% CI: 1.527-2.750).

CONCLUSIONS

Young patients treated with PN demonstrate an overall survival advantage. This survival advantage is observed after an early follow-up even in those without comorbidities. It is still not clear if the survival advantage seen is due to treatment itself or selection bias.

Hypoandrogenism is Prevalent in Males With Urethral Stricture Disease and is Associated with Longer Strictures

OBJECTIVE

To assess the association of hypoandrogenism (HA) with urethral stricture disease in a series of patients undergoing urethroplasty at 2 institutions. HA has recently been associated with increased urethral atrophy in artificial sphincter failures and decreased androgen receptors and periurethral vascularity. HA might be an etiologic factor in urethral stricture disease.

METHODS

We reviewed the charts in 202 men with anterior urethral strictures between 2011 and 2017. We excluded patients with radiation-induced stricture, previous prostatectomy, previous urethroplasty, pelvic fracture-related strictures, or those on testosterone replacement. We defined HA by a total testosterone of less than 300 ng/dL. We used as age-matched cohort from a national database (National Health and Nutrition Examination Survey), as a reference. Stricture characteristics, such as length, location, and etiology were compared in HA and eugonadal groups.

RESULTS

Of 202 men with anterior urethral strictures, we excluded 45. Of the remaining 157 patients, 115 (73%) had preoperative testosterone measurements. Overall, hypoandrogenism (HA) was found in 65 of 115 (57%) men in the urethral stricture group compared with 28% of age-matched men in the national database. Mean stricture length in HA and eugonadal men was 7.2 cm and 4.8 cm, respectively (P = .02).

CONCLUSION

HA may be more prevalent and associated with increased disease severity in men with anterior urethral strictures. The relationship between HA and stricture formation and its potential impact on therapeutic outcomes merit further prospective investigation.

Acute Page kidney immediately following blunt trauma to a solitary pediatric kidney

Page kidney refers to the occurrence of hypertension secondary to renal compression and is usually associated with a subcapsular or perinephric hematoma. It generally occurs weeks to months after the initial injury. We report on a case of Page kidney occurring acutely after Grade IV blunt renal trauma in a pediatric patient with a solitary kidney following a tobogganing accident. The child was initially managed conservatively and discharged after six days bed-rest. He re-presented post-injury Day 12 with recurrent hematuria, anemia, hypertension, and renal failure that required eventual, and successful, surgical exploration.

Incidence and seasonality of respiratory viruses among medically attended children with acute respiratory infections in an Ecuador birth cohort, 2011-2014

Background

Ecuador annually has handwashing and respiratory hygiene campaigns and seasonal influenza vaccination to prevent respiratory virus illnesses but has yet to quantify disease burden and determine epidemic timing.

Methods

To identify respiratory virus burden and assess months with epidemic activity, we followed a birth cohort in northwest Ecuador during 2011–2014. Mothers brought children to the study clinic for routine checkups at ages 1, 2, 3, 5, and 8 years or if children experienced any acute respiratory illness symptoms (e.g., cough, fever, or difficulty breathing); clinical care was provided free of charge. Those with medically attended acute respiratory infections (MAARIs) were tested for common respiratory viruses via real‐time reverse‐transcription polymerase chain reaction (rRT‐PCR).

Results

In 2011, 2376 children aged 1–4 years (median 35 months) were enrolled in the respiratory cohort and monitored for 7017.5 child‐years (cy). The incidence of respiratory syncytial virus (RSV) was 23.9 (95% CI 17.3–30.5), influenza 10.6 (2.4–18.8), adenoviruses 6.7 (4.6–28.0), parainfluenzas 5.0 (2.3–10.5), and rhinoviruses, bocaviruses, human metapneumoviruses, seasonal coronaviruses, and enteroviruses <3/100 cy among children aged 12–23 months and declined with age. Most (75%) influenza detections occurred April–September.

Conclusion

Cohort children frequently had MAARIs, and while the incidence decreased rapidly among older children, more than one in five children aged 12–23 months tested positive for RSV, and one in 10 tested positive for influenza. Our findings suggest this substantial burden of influenza occurred more commonly during the winter Southern Hemisphere influenza season.

Partial Adrenalectomy-Why Should it be Considered?

INTRODUCTION

When a biochemically active adrenal mass is found, surgery is usually recommended. While partial adrenalectomy is increasing in popularity for small adrenal masses, it is not clear which patients will benefit from adrenal sparing to preserve adrenal function in case of contralateral adrenal pathology. We reviewed the available literature to evaluate the frequency of bilaterality of adrenal involvement with most common primary adrenal tumors and the frequency of other pathologies potentially threatening the health of the adrenal gland.

METHODS

We reviewed the available PubMed® literature to evaluate the reported bilaterality of primary adrenal tumors, including hereditary and nonhereditary pheochromocytomas, aldosterone producing adenomas and cortisol producing adenomas, and identified 25 articles describing the frequency of bilaterality of adrenal masses. We also reviewed the literature to assess the etiologies of adrenal damage due to other pathological processes that may affect the adrenal gland in the life span of a patient and calculated the combined probability for adrenal damage.

RESULTS

Bilaterality of adrenal tumors in hereditary and nonhereditary diseases ranged from 4.25% to 80%. Hereditary pheochromocytomas were bilateral in up to 80% of cases while nonhereditary pheochromocytomas were bilateral in up to 25%. Aldosterone producing adenomas were bilateral in about 4% of cases while only case reports reported bilaterality in cortisol producing tumors. Additionally, review of other processes, such as infections, infiltrative etiologies, adrenal metastasis and others accounted for about a 1% chance of adrenal damage from all possible causes.

CONCLUSIONS

Partial adrenalectomy may be a valid option for patients with hereditary syndromes as there is an increased likelihood of disease in the contralateral gland. Pheochromocytomas followed by aldosterone producing adenomas appear to have the highest rate of bilateral involvement. Coupled with the possibility that an additional 1% of the population may have adrenals affected by various pathological processes, partial adrenalectomy in patients with metabolically active adrenal tumors should be considered.