The Impact of Vitamin A Deficiency on Tuberculosis Progression.

BACKGROUND: Although previous studies have shown that vitamin A deficiency is associated with incident tuberculosis (TB) disease, the direction of the association has not been established. We investigated the impact of vitamin A deficiency on TB disease progression. METHODS: We conducted a longitudinal cohort study nested within a randomized clinical trial among HIV-infected patients in Haiti. We compared serial vitamin A levels in individuals who developed TB disease to controls matched on age, gender, follow-up time, and time to antiretroviral therapy initiation. We also evaluated histopathology, bacterial load, and immune outcomes in TB infection in a guinea pig model of dietary vitamin A deficiency. RESULTS: Among 773 participants, 96 developed incident TB during follow-up, 62.5% (60) of whom had stored serum samples obtained 90-365 days before TB diagnosis. In age- and sex- adjusted and multivariate analyses, respectively, incident TB cases were 3.99 times (95% confidence interval [CI], 2.41 to 6.60) and 3.59 times (95% CI, 2.05 to 6.29) more likely to have been vitamin A deficient than matched controls. Vitamin A-deficient guinea pigs manifested more extensive pulmonary pathology, atypical granuloma morphology, and increased bacterial growth after experimental TB infection. Reintroduction of dietary vitamin A to deficient guinea pigs after established TB disease successfully abrogated severe disease manifestations and altered cellular immune profiles. CONCLUSIONS: Human and animal studies support the role of baseline vitamin A deficiency as a determinant of future TB disease progression.

Large reduction in opioid prescribing by a multipronged behavioral intervention after major urologic surgery.

BACKGROUND: Surgeons play a pivotal role in combating the opioid crisis that currently grips the United States. Changing surgeon behavior is difficult, and the degree to which behavioral science can steer surgeons toward decreased opioid prescribing is unclear. METHODS: This was a single-institution, single-arm, pre- and postintervention study examining the prescribing of opioids by urologists for adult patients undergoing prostatectomy or nephrectomy. The primary outcome was the quantity of opioids prescribed in oral morphine equivalents (OMEs) after hospital discharge. The primary exposure was a multipronged behavioral intervention designed to decrease opioid prescribing. The intervention had 3 components: 1) formal education, 2) individual audit feedback, and 3) peer comparison performance feedback. There were 3 phases to the study: a pre-intervention phase, an intervention phase, and a washout phase. RESULTS: Three hundred eighty-two patients underwent prostatectomy, and 306 patients underwent nephrectomy. The median OMEs decreased from 195 to 19 in the prostatectomy patients and from 200 to 0 in the nephrectomy patients (P < .05 for both). The median OMEs prescribed did not increase during the washout phase. Prostatectomy patients discharged with opioids had higher levels of anxiety than patients discharged without opioids (P < .05). Otherwise, prostatectomy and nephrectomy patients discharged with and without opioids did not differ in their perception of postoperative pain management, activity levels, psychiatric symptoms, or somatic symptoms (P > .05 for all). CONCLUSIONS: Implementing a multipronged behavioral intervention significantly reduced opioid prescribing for patients undergoing prostatectomy or nephrectomy without compromising patient-reported outcomes.

Bladder underactivity induced by prolonged pudendal afferent activity in cats.

The purpose of this study was to determine the effects of pudendal nerve stimulation (PNS) on reflex bladder activity and develop an animal model of underactive bladder (UAB). In six anesthetized cats, a bladder catheter was inserted via the urethra to infuse saline and measure pressure. A cuff electrode was implanted on the pudendal nerve. After determination of the threshold intensity (T) for PNS to induce an anal twitch, PNS (5 Hz, 0.2 ms, 2 T or 4 T) was applied during cystometrograms (CMGs). PNS (4-6 T) of 30-min duration was then applied repeatedly until bladder underactivity was produced. Following stimulation, control CMGs were performed over 1.5-2 h to determine the duration of bladder underactivity. When applied during CMGs, PNS (2 T and 4 T) significantly (P < 0.05) increased bladder capacity while PNS at 4 T also significantly (P < 0.05) reduced bladder contraction amplitude, duration, and area under contraction curve. Repeated application of 30-min PNS for a cumulative period of 3-8 h produced bladder underactivity exhibiting a significantly (P < 0.05) increased bladder capacity (173 ± 14% of control) and a significantly (P < 0.05) reduced contraction amplitude (50 ± 7% of control). The bladder underactivity lasted more than 1.5-2 h after termination of the prolonged PNS. These results provide basic science evidence supporting the proposal that abnormal afferent activity from external urethral/anal sphincter could produce central inhibition that underlies nonobstructive urinary retention (NOUR) in Fowler's syndrome. This cat model of UAB may be useful to investigate the mechanism by which sacral neuromodulation reverses NOUR in Fowler's syndrome.

Pudendal Nerve Block by Low-Frequency (≤1 kHz) Biphasic Electrical Stimulation.

OBJECTIVES: To test the hypothesis that poststimulation block of nerve conduction can be achieved by low-frequency (≤1 kHz) biphasic stimulation (LFBS). MATERIALS AND METHODS: A tripolar cuff electrode was placed around the pudendal nerve in cats to deliver LFBS (1 kHz, 500 Hz, and 100 Hz). Two bipolar hook electrodes were placed central and distal to the cuff electrode to induce external urethral sphincter (EUS) contractions. A catheter was inserted into the urethra to record EUS contraction pressure. Pudendal nerve block by LFBS was confirmed by the failure of the central hook electrode stimulation to induce EUS contractions, while the distal hook electrode stimulation still induced contractions. RESULTS: Pudendal nerve conduction was completely blocked by LFBS at different frequencies (1 kHz, 500 Hz, and 100 Hz) after terminating LFBS. The post-LFBS block induced at the minimal stimulation intensity and duration was fully reversible within the same time period (10-15 min on average) for the three frequencies. However, the stimulation duration to induce block significantly (p < 0.05) increased from 23 ± 8 sec to 95 ± 14 sec when frequency increased from 100 Hz to 1 kHz. CONCLUSION: This study discovered that LFBS (≤1 kHz), like high-frequency (≥5 kHz) biphasic stimulation (HFBS), can induce poststimulation block. The result provides support for the theory that biphasic stimulation waveforms block axonal conduction by changing intracellular and extracellular ion concentrations. The post-LFBS block provides the opportunity to develop new neuromodulation devices for clinical applications where initial nerve firing is acceptable.

Superficial peroneal neuromodulation of nonobstructive urinary retention in cats.

AIMS: To determine if superficial peroneal nerve stimulation (SPNS) can improve nonobstructive urinary retention (NOUR). METHODS: In α-chloralose anesthetized cats, NOUR was induced by repetitive application (4-16 times) of 30-minute tibial nerve stimulation (TNS: 5 Hz frequency, 0.2 ms pulse width) at 4 to 6 times threshold intensity (T) for inducing toe twitches. SPNS (1 Hz, 0.2 ms) at 2 to 4 times threshold intensity (T) for inducing posterior thigh muscle contractions was applied either continuously (SPNSc) during a cystometrogram (CMG) or during voiding (SPNSv) by a surgically implanted cuff electrode or by skin surface electrodes to determine if the stimulation reduced NOUR induced by prolonged TNS. RESULTS: During control CMGs, efficient (86.4% ± 5.5%) voiding occurred with a postvoid residual (PVR) volume equal to 14.9% ± 6.2% of control bladder capacity. NOUR elicited by prolonged TNS significantly (P < .05) increased bladder capacity to 168.6% ± 15.5% of control, reduced voiding efficiency to 30.4% ± 4.8%, and increased PVR to 109% ± 9.2% of control. Using the implanted cuff electrode, SPNSc and SPNSv significantly (P < .05) increased voiding efficiency to 66.7% ± 7.4% and 65.0% ± 5.9%, respectively, and reduced PVR to 52.2% ± 11.4% and 64.3% ± 11.6%, respectively. SPNSc but not SPNSv significantly (P < .05) reduced bladder capacity to 133.4% ± 15% of control. Transcutaneous SPNSv but not SPNSc also significantly (P < .05) reversed the TNS-induced NOUR responses. CONCLUSIONS: This study shows that SPNS is effective in reversing NOUR induced by prolonged TNS. Transcutaneous SPNS provides the opportunity to develop a noninvasive neuromodulation therapy for NOUR to treat more patients than current sacral neuromodulation therapy.

Using a Multi-pronged Behavioral Intervention to Standardize Antibiotic Prophylaxis at the Time of Foley Catheter Removal After Radical Prostatectomy.

OBJECTIVE: To identify antibiotic prescribing patterns at the time of foley catheter removal after radical prostatectomy and implement a multi-pronged behavioral intervention to standardize antibiotic use. METHODS: This was a single-institution study examining the prescribing of antibiotics at the time of foley catheter removal after radical prostatectomy. Pre-intervention data were collected retrospectively to establish baselines for antibiotic prescribing, patient characteristics, and urinary tract infection rates. A single dose of an oral antibiotic taken at the time of foley catheter removal was recommended as the standard antibiotic protocol. A multi-pronged behavioral intervention was used to encourage compliance with our protocol. Adherence to the protocol, quantity of antibiotics prescribed, and rate of urinary tract infection were recorded prospectively. Durability of the intervention was evaluated during a post-intervention phase. RESULTS: A total of 416 patients and 6 surgeons were included in the study. Accordance with the standardized antibiotic protocol was 59% in the pre-intervention phase and 91% in the intervention phase (P = .03). No patients in the intervention or post-intervention phase were prescribed more than one dose of an antibiotic. The rate of urinary tract infection did not differ across the study phases. CONCLUSION: Implementation of a multi-pronged behavioral intervention resulted in a high rate of surgeon compliance with a standardized antibiotic protocol. This led to a significant reduction in antibiotic use with no change in the rate of urinary tract infection after foley catheter removal after radical prostatectomy.

Utilizing a Questionnaire to Implement a Risk-based Antibiotic Prophylaxis Protocol for Transrectal Prostate Biopsy.

OBJECTIVE: To develop and evaluate a risk-based antibiotic prophylaxis protocol for patients undergoing transrectal prostate biopsy. METHODS: We created a risk-based protocol for antibiotic prophylaxis before transrectal prostate biopsy. Patients were screened for infection risk-factors with a self-administered questionnaire. The protocol was implemented from January 1, 2020 to March 31, 2020. We compared patient risk-factors, antibiotic regimens, and 30-day infection rates for patients undergoing transrectal prostate biopsies during the intervention and for a 3-month period before the intervention. RESULTS: There were 116 prostate biopsies in the preintervention group and 104 in the intervention group. Although there was no significant difference in the number of high-risk patients between the 2 groups (48% vs 55%; P = .33), the percentage of patients treated with augmented prophylaxis decreased from 74% to 45% (P = 0.03). The duration of antibiotic administration and the median number of doses prescribed also decreased significantly. Despite significant decreases in antibiotic use, there were no differences in infection rates (5% vs 5%; P = .90) or sepsis rates (1% vs 2%; P = .60). CONCLUSION: We developed a risk-based protocol for prophylactic antibiotics before prostate biopsy. The protocol was associated with less antibiotic use but did not lead to an increase in infectious complications.

Opioid-Free Ureteroscopy: Are Academic Urologists Lagging Behind Private Practice?

OBJECTIVE: To examine overall trends in opioid prescribing after ureteroscopy and compared opioid use between private and academic practice settings. We also analyzed the potential for spillover effect from an unrelated opioid-reduction initiative for major oncologic surgery. METHODS: We conducted a retrospective chart review of all ureteroscopies performed within our system at four distinct time points from 2016-2019. We recorded the type and number of opioid pills prescribed and calculated oral morphine equivalents. Analysis included comparison between community and academic hospitals as well as pre- and post-initiative. RESULTS: 555 patients undergoing ureteroscopy and 29 attending surgeons were included in the analysis. The median prescription size per ureteroscopy decreased throughout the study period in both the private and academic settings. From 2016-2017, median oral morphine equivalents (OMEs) decreased from 60 to 0 in the private setting and remained at 0 for the duration of the study period. Opioid reduction in the academic setting lagged behind private practitioners but median OMEs did steadily decrease to 0 in 2019. No significant spillover effect was observed. CONCLUSION: Since 2016, opioid prescribing following ureteroscopy has decreased in both the private and academic practice settings. Notably, private practice urologists achieved a median of 0 opioids 2 years prior to academic urologists. These data suggest that, in some circumstances, academic institutions may have been slower to respond to the opioid epidemic.

Restoring both continence and micturition after chronic spinal cord injury by pudendal neuromodulation.

Neurogenic bladder management after spinal cord injury (SCI) is very challenging. Daily urethral catheterization is most commonly used to empty the bladder, which causes frequent infections of the lower urinary tract. This study reports a novel idea to restore both continence and micturition after SCI by an implantable pudendal nerve stimulator (PNS). The PNS was surgically implanted in four cats with complete SCI at T9-T10 spinal level and tested weekly for 13-14 weeks under awake conditions. These chronic SCI cats consistently exhibited large residual bladder volumes (average 40-50 ml) due to their inability to void efficiently, while urine leakage also occurred frequently. The PNS which consisted of stimulating the pudendal nerve at 20-30 Hz to trigger a spinal reflex bladder contraction and at the same time blocking the pudendal nerves bilaterally with 10 kHz stimulation to relax the external urethral sphincter and reduce the urethral outlet resistance successfully induced highly efficient (average 80-100%), low pressure (<50 cmH2O) voiding. The PNS at 5 Hz also promoted urine storage by inhibiting reflex bladder activity and increasing bladder capacity. At the end of 14-week chronic testing, low pressure efficient voiding induced by PNS was further confirmed under anesthesia by directly measuring voiding pressure using a bladder catheter inserted through the bladder dome. This study demonstrated the efficacy and safety of the PNS in awake chronic SCI cats, suggesting that a novel neuroprosthesis can be developed for humans to restore bladder function after SCI by stimulating and/or blocking the pudendal nerves.