Exploring variations in recommended first-choice therapy for complicated urinary tract infections in males: Insights from outpatient settings across age, race, and ethnicity

INTRODUCTION

There are known disparities in the treatment of infectious diseases. However, disparities in treatment of complicated urinary tract infections (UTIs) are largely uninvestigated.

OBJECTIVES

We characterized UTI treatment among males in Veterans Affairs (VA) outpatient settings by age, race, and ethnicity and identified demographic characteristics predictive of recommended first-choice antibiotic therapy.

METHODS

We conducted a national, retrospective cohort study of male VA patients diagnosed with a UTI and dispensed an outpatient antibiotic from January 2010 through December 2020. Recommended first-choice therapy for complicated UTI was defined as use of a recommended first-line antibiotic drug choice regardless of area of involvement (ciprofloxacin, levofloxacin, or sulfamethoxazole/trimethoprim) and a recommended duration of 7 to 10 days of therapy. Multivariable models were used to identify demographic predictors of recommended first-choice therapy (adjusted odds ratio [aOR] > 1).

RESULTS

We identified a total of 157,898 males diagnosed and treated for a UTI in the outpatient setting. The average antibiotic duration was 9.4 days (±standard deviation [SD] 4.6), and 47.6% of patients were treated with ciprofloxacin, 25.1% with sulfamethoxazole/trimethoprim, 7.6% with nitrofurantoin, and 6.6% with levofloxacin. Only half of the male patients (50.6%, n = 79,928) were treated with recommended first-choice therapy (first-line drug choice and appropriate duration); 77.6% (n = 122,590) were treated with a recommended antibiotic choice and 65.9% (n = 104,070) with a recommended duration. Age 18-49 years (aOR 1.07, 95% confidence interval [CI] 1.03-1.11) versus age ≥65 years was the only demographic factor predictive of recommended first-choice therapy.

CONCLUSIONS

Nearly half of the patients included in this study did not receive recommended first-choice therapies; however, racial and ethnic disparities were not identified. Underutilization of recommended first-choice antibiotic therapy in complicated UTIs continues to be an area of focus for antimicrobial stewardship programs.

Advancements in Novel Live Biotherapeutic Products for Clostridioides difficile Infection Prevention

The profound impact of the human microbiome on health and disease has captivated the interest of clinical and scientific communities. The human body hosts a vast array of microorganisms collectively forming the human microbiome, which significantly influences various physiological processes and profoundly shapes overall well-being. Notably, the gut stands out as an exceptional reservoir, harboring the most significant concentration of microorganisms, akin to an organ in itself. The gut microbiome's composition and function are influenced by genetics, environment, age, underlying conditions, and antibiotic usage, leading to dysbiosis and pathogenesis, such as Clostridioides difficile infection (CDI). Conventional CDI treatment, involving antibiotics like oral vancomycin and fidaxomicin, fails to address dysbiosis and may further disrupt gut microbial communities. Consequently, emerging therapeutic strategies are focused on targeting dysbiosis and restoring gut microbiota to advance CDI therapeutics. Fecal microbiota transplantation (FMT) has demonstrated remarkable efficacy in treating recurrent CDI by transferring processed stool from a healthy donor to a recipient, restoring gut dysbiosis and enhancing bacterial diversity. Moreover, 2 newer Food and Drug Administration (FDA)-approved live biotherapeutic products (LBP), namely, Fecal Microbiota Live-JSLM and Fecal Microbiota Spores Live-BRPK, have shown promise in preventing CDI recurrence. This review explores the role of the gut microbiota in preventing and treating CDI, with an emphasis on gut-based interventions like FMT and fecal microbiota-based products that hold potential for gut restoration and prevention of CDI recurrence. Understanding the microbiome's impact on CDI prevention and treatment offers valuable insights for advancing future CDI therapeutics.

Elevated Interferon Alpha in the Serum of Laboratory Strains of Mice and Porcine Serum by ELISA

We examined Interferon (IFN)-Alpha and -Beta levels in pooled sera and individual bleeds from C57/Bl, Balb/C and CD-1 mice. 20 Individuals from each strain from two independent colonies were evaluated in commercial assays. The IFN-Beta ELISA detected IFN in 1 of the 60 individuals while the IFN-Alpha assay which detects all 14 subtypes measured IFN in 13 of 60. 5 individuals exhibited greater than 4 pg/ml of IFN-Alpha detected. Specificity was demonstrated by knockdown of the signal using non-biotinylated detection antibody. 14 of 54 porcine sera samples from 4 independent sources were positive for IFN alpha by an ELISA under development, and similar knock-down experiments suggest specificity. This is in contrast to human sera/plasma samples where less than 3% of healthy donor samples have quantifiable IFN-Alpha or -Beta above 0.5 pg/ml. This study may raise questions about the regulation of the IFN system in different species and the potential of these differences to affect experimental results in a variety of models.

Interferon-beta therapy increases concentration of soluble interferon alpha/beta receptor in multiple sclerosis patient serum. (P4156)

Interferon-beta is a frontline treatment for Multiple Sclerosis and yet the molecule’s mechanism of action in this disease is not fully understood. We have examined the serum/plasma concentrations of soluble Interferon alpha/beta receptor 2 (sIFNAR2) using a newly developed IFNAR2 ELISA in 35 normal human donors, 23 MS patients not on IFN therapy, and 29 MS patients on IFN therapy. Other biomarkers, IFN-beta, and Type I IFN activity were also assessed in most samples. In most patients receiving IFN-beta therapy, IFN beta mass as well as IFN bioactivity can be detected in the serum. Consistent with previous literature, IFN bioactivity is lower than that which would be predicted based on IFN beta mass. For patients on IFN-beta therapy, we observe that sIFNAR2 concentration is significantly (p=0.0001) higher than that in MS patients on IFN-free therapy and relative to normal donors (p=0.0007). Normal donor sIFNAR2 concentration does not significantly differ from that of MS patients on IFN-free therapy. These results expand upon previous literature which suggests that the mRNA encoding a soluble form of the IFN receptor is increased by long term IFN-beta therapy. Data from additional samples, potential mechanisms, and correlations to other biomarkers will be discussed.

Analysis of Type I and III interferon levels in the sera of normal and autoimmune donors. (101.37)

We have begun examining serum levels of Type I and III interferons in normal and autoimmune donors by ELISA and a Type I reporter gene activity assay to determine if there are expression pattern signatures of these diseases. Samples were obtained from normal donors and patients with Systemic Lupus Erythematosus, Rheumatoid Arthritis or Multiple Sclerosis and assayed for IFN-α), IFN-β, IFN-ω, and IFN. Normal controls had little detectable IFN-α, IFN-ω, or Type I IFN activity. Low levels of IFN-β were detected in 15% of the normal controls. Approximately 35% of the normal controls had detectable IFN-λ. In the Lupus samples, 45% had detectable IFN-α. IFN-ω and IFN-β were detected in 20 and 40%, respectively, of the Lupus samples. Overall, greater than 80% of the Lupus samples had detectable Type-I IFN. Rheumatoid arthritis samples may have elevated IFN-β and IFN-ω relative to normal controls, but not IFN-α. Multiples sclerosis samples had a slight tendency towards elevated IFN-β. A low percentage of Lupus and multiple sclerosis samples had detectable Type-I IFN activity by the reporter gene assay. None of the samples displayed significant differences in Type III IFN expression. Multiplex ELISA was used to examine a subset of the samples for cytokine profiles and in Lupus samples IL-13 was decreased. In arthritis samples IL-8 and IL-23 were elevated, while in Multiple Sclerosis samples IL-2, IL-4 and IL-10 were elevated. The implications of these results will be discussed.

The differential activity of interferon-α subtypes is consistent among distinct target genes and cell types

IFN-α proteins have been described to originate from 14 individual genes and allelic variants. However, the exceptional diversity of IFN-α and its functional impact are still poorly understood. To characterize the biological activity of IFN-α subtypes in relation to the cellular background, we investigated the effect of IFN-α treatment in primary fibroblasts and endothelial cells of vascular or lymphatic origin. The cellular response was evaluated for 13 distinct IFN-α proteins with respect to transcript regulation of the IFN-stimulated genes (ISGs) IFIT1, ISG15, CXCL10, CXCL11 and CCL8. The IFN-α proteins displayed a remarkably consistent potency in gene induction irrespective of target gene and cellular background which led to the classification of IFN-α subtypes with low (IFN-α1), intermediate (IFN-α2a, -4a, -4b, -5, -16, -21) and high (IFN-α2b, -6, -7, -8, -10, -14) activity. The differential potency of IFN-α classes was confirmed at the ISG protein level and the functional protection of cells against influenza virus infection. Differences in IFN activity were only observed at subsaturating levels of IFN-α proteins and did not affect the time course of ISG regulation. Cell-type specific responses were apparent for distinct target genes independent of IFN-α subtype and were based on different levels of basal versus inducible gene expression. While fibroblasts presented with a high constitutive level of IFIT1, the expression in endothelial cells was strongly induced by IFN-α. In contrast, CXCL10 and CXCL11 transcript levels were generally higher in endothelial cells despite a pronounced induction by IFN-α in fibroblasts. In summary, the divergent potency of IFN-α proteins and the cell-type specific regulation of individual IFN target genes may allow for the fine tuning of cellular responses to pathogen defense.

Sustained-release potassium chloride overdose

BACKGROUND

Although ingestion of sustained-release potassium supplements can cause life-threatening hyperkalemia in patients with abnormal renal function, only a few previous reports suggest that this may occur in patients with normal renal function. We report 2 cases of hyperkalemia in patients with normal renal function who developed hyperkalemia after ingesting sustained-release potassium preparations and describe the use of radiography and whole-bowel irrigation in their care.

CASE REPORTS

The first patient is a 50-year-old woman who ingested 100 K-Dur tablets (each tablet containing 750 mg KCl or 10 mEq potassium) in a suicide attempt 1 hour prior to presenting to the emergency department. She developed a peak serum potassium level of 9.7 mEq/L and had transient, potentially life-threatening electrocardiographic changes. The second patient was a 17-year-old man who ingested 20 to 30 Klor-Con tablets (each tablet containing 750 mg KCl or 10 mEq potassium) in a suicide attempt 10 hours prior to presentation. Although he developed a peak serum potassium level of 6.1 mEq/L, he had a persistently normal electrocardiogram. In both patients, the tablets were visualized on abdominal radiographs and the gastrointestinal tracts of both were successfully decontaminated using whole-bowel irrigation.

DISCUSSION

Although the sensitivity and specificity are unknown, the abdominal radiograph appears to be useful in detecting sustained-release potassium tablets. Whole-bowel irrigation as a primary method of gastrointestinal decontamination also appears to be effective although its use is not previously reported for sustained-release potassium overdoses.

Normal intrauterine pregnancy is unlikely in emergency department patients with either menstrual days > 38 days or beta-hCG > 3,000 mIU/mL, but without a gestational sac on ultrasonography

OBJECTIVE

To determine whether the absence of a gestational sac on transvaginal ultrasonography in patients with a quantitative beta-human chorionic gonadotropin (beta-hCG) > 3,000 mIU/mL and/or menstrual days > 38 excludes the diagnosis of a normal intrauterine pregnancy (IUP).

METHODS

A retrospective analysis was performed of ED patients evaluated from August 1991 to December 1994 at an urban teaching hospital. Patients presented with abdominal pain and/or vaginal bleeding and had a positive serum beta-hCG test. Patients who had transvaginal ultrasonographies performed during the ED visit that were read as indeterminate were reviewed. Menstrual days were determined by subtracting the date of the last normal menstrual period (LMP) from the ED visit date. ED beta-hCGs were quantified. Patients were excluded if the LMP or quantitative beta-hCG result was not available or if the final diagnosis could not be definitively determined.

RESULTS

248 patients met eligibility criteria; of these, 54 were excluded. Therefore, 194 patients were enrolled. Menstrual days ranged from 5 to 151, with a median of 54 days. Of 143 patients with menstrual days > 38 and no gestational sac by ultrasonography, only 4 (2.8%) had a final diagnosis of normal IUP. The menstrual days for the 4 normal IUPs were 39, 41, 42, and 59 days. beta-hCGs ranged from 19 to 151,926 mIU/mL, with a median of 2,410 mIU/mL. None of the 74 patients with a beta-hCG > 3,000 mIU/mL and no gestational sac by ultrasonography had a final diagnosis of normal IUP.

CONCLUSION

In patients with either a beta-hCG > 3,000 mIU/mL or menstrual days > 38 and no gestational sac by transvaginal ultrasonography, the likelihood of a normal IUP is low.

Crystallization and preliminary crystallographic analysis of E. coli uridine 5'-diphospho-N-acetylenolpyruvylglucosamine reductase in two new crystal forms

Uridine 5'-diphospho-N-acetylenolpyruvylglucosamine reductase (MurB), the second enzyme in the peptidoglycan synthetic pathway of Escherichia coli, has been crystallized in two previously unreported forms, one orthorhombic and the other monoclinic. MurB (molecular mass 38 kDa) crystallizes in a range of conditions that utilize polyethylene glycol fractions as precipitants, and crystals can be grown with or without the enzyme's substrate, uridine 5'-diphospho-N-acetylenolpyruvylglucosamine. X-ray diffraction from crystals of the orthorhombic form extends to 2 A resolution and shows the symmetry and systematic absences of space group P2(1)2(1)2(1). These crystals show significant variations in cell dimensions at room temperature and at 100 K. A crystal used to collect a 2.0 A resolution data set at a synchrotron source showed cell dimensions at ca 100 K of a = 51.0, b = 79.3 and c = 87.1 A, indicating one molecule peroasymmetric unit. The monoclinic crystals scatter X-rays to 3.0 A resolution consistent with space group P2(1), unit-cell dimensions (ca 100 K) a = 50.7, b = 92.4, c = 85.5 A, and beta = 104 degrees, and two molecules per asymmetric unit. Mercury derivatives have been prepared with both orthorhombic and monoclinic forms, and efforts are underway to exploit these derivatives to determine the structure of this protein.

Refined solution structure of human profilin I

Profilin is a ubiquitous eukaryotic protein that binds to both cytosolic actin and the phospholipid phosphatidylinositol-4,5-bisphosphate. These dual competitive binding capabilities of profilin suggest that profilin serves as a link between the phosphatidyl inositol cycle and actin polymerization, and thus profilin may be an essential component in the signaling pathway leading to cytoskeletal rearrangement. The refined three-dimensional solution structure of human profilin I has been determined using multidimensional heteronuclear NMR spectroscopy. Twenty structures were selected to represent the solution conformational ensemble. This ensemble of structures has root-mean-square distance deviations from the mean structure of 0.58 A for the backbone atoms and 0.98 A for all non-hydrogen atoms. Comparison of the solution structure of human profilin to the crystal structure of bovine profilin reveals that, although profilin adopts essentially identical conformations in both states, the solution structure is more compact than the crystal structure. Interestingly, the regions that show the most structural diversity are located at or near the actin-binding site of profilin. We suggest that structural differences are reflective of dynamical properties of profilin that facilitate favorable interactions with actin. The global folding pattern of human profilin also closely resembles that of Acanthamoeba profilin I, reflective of the 22% sequence identity and approximately 45% sequence similarity between these two proteins.

Orientation of peptide fragments from Sos proteins bound to the N-terminal SH3 domain of Grb2 determined by NMR spectroscopy

NMR spectroscopy has been used to characterize the protein-protein interactions between the mouse Grb2 (mGrb2) N-terminal SH3 domain complexed with a 15-residue peptide (SPLLPKLPP-KTYKRE) corresponding to residues 1264-1278 of the mouse Sos-2 (mSos-2) protein. Intermolecular interactions between the peptide and 13C-15N-labeled SH3 domain were identified in half-reverse-filtered 2D and 3D NOESY experiments. Assignments for the protons involved in interactions between the peptide and the SH3 domain were confirmed in a series of NOESY experiments using a set of peptides in which different leucine positions were fully deuterated. The peptide ligand-binding site of the mGrb2 N-terminal SH3 domain is defined by the side chains of specific aromatic residues (Tyr7, Phe9, Trp36, Tyr52) that form two hydrophobic subsites contacting the side chains of the peptide Leu4 and Leu7 residues. An adjacent negatively charged subsite on the SH3 surface is likely to interact with the side chain of a basic residue at peptide position 10 that we show to be involved in binding. The peptide-binding site of the SH3 is characterized by large perturbations of amide chemical shifts when the peptide is added to the SH3 domain. The mGrb2 N-terminal SH3 domain structure in the complex is well-defined (backbone RMSD of 0.56 +/- 0.21 calculated over the backbone N, C alpha, and C atoms of residues 1-54). The structure of the peptide in the complex is less well-defined but displays a distinct orientation.(ABSTRACT TRUNCATED AT 250 WORDS)