Patient Factors Affect Ergonomic Strain of Endoscopists During Colonoscopy.

INTRODUCTION: Endoscopic procedures place a great deal of muscular strain on providers, especially over the span of their careers. In this study we quantitatively analyzed the effects of patient factors such as age, body mass index, and sex on the ergonomics of endoscopists performing colonoscopies. METHODS: Surface electromyography (sEMG) was used to measure ergonomic strain of physicians while performing colonoscopies in several key muscle groups. The percent of the maximum voluntary contraction (%MVC) was used as a measure of muscular strain. Data was then analyzed based on the patient characteristics above. RESULTS: Endoscopists performing colonoscopies on female patients (n = 47) experienced significantly higher ergonomic strain in their right trapezius and right posterior forearm muscle groups when compared to colonoscopies performed on males (n = 35) (%MVC R-trapezius: Male: 8.2; Female: 8.9; p = 0.048); (%MVC R-posterior forearm: Male: 10.4; Female: 11.6; p = 0.0006). Operators experienced greater strain in the same muscle groups when performing colonoscopies on patients with BMI ≤ 25 (n = 25) when compared to patients with BMI > 25 (n = 57) (%MVC R-trapezius: BMI < 25: 9.7; BMI ≥ 25: 8.2; p = 0.0002); (%MVC R-posterior forearm: BMI < 25: 11.9; BMI ≥ 25: 10.8; p = 0.0001). CONCLUSION: Physicians experienced greater ergonomic strain when performing colonoscopies on female patients and on patients with a BMI < 25. We believe that these factors potentially impact the tortuosity of the colon and therefore influence the difficulty of navigating the endoscope. These results may aid physicians in gauging the anticipated difficulty of colonoscopies based on patient factors. Increased awareness of their posturing and ergonomics during challenging cases will alleviate musculoskeletal injuries in the long run.

Successful Treatment of Epstein-Barr Virus-Induced Necrotizing Retinitis with Intravitreous Ganciclovir, Foscarnet, and Methotrexate.

This is a report of an immunocompromised 49-year-old renal transplant patient with Epstein-Barr virus (EBV)-induced necrotizing retinitis (NR). The patient with NR underwent diagnostic vitrectomy. Polymerase chain reaction (PCR) testing of the vitreous fluid was positive for EBV (25,000 IU/mL) and negative for all other organisms. The patient was treated with intravitreous ganciclovir and foscarnet. After only mild clinical improvement in retinitis and an increased quantitative EBV PCR (69,000 IU/mL), intravitreous methotrexate was added to the aforementioned intravitreous antiviral injections. After eight rounds of ganciclovir/foscarnet and three injections of methotrexate, the NR resolved, the quantitative EBV PCR decreased to 29 IU/mL, and the patient's visual acuity improved. To our knowledge, this is only the second case report to demonstrate efficacy of intravitreous methotrexate in an immunocompromised patient with EBV-induced NR. Intravitreous methotrexate combined with ganciclovir and foscarnet may be an effective treatment strategy for patients with PCR-positive EBV-induced NR that does not respond to conventional antiviral therapy.

Fungus packs a punch in the gut.

The impact of intestinal fungi on host physiology and their mechanisms of interaction are incompletely understood. In a recent issue of Cell, Leonardi et al. (2022) showed that mucosal fungi induce intestinal Th17 cells to produce IL-22 and IL-17A. IL-22 acts on the gut epithelium to protect barrier integrity, whereas IL-17 acts on IL-17RA+ neurons to enhance sociability.

An amygdala circuit that suppresses social engagement.

Innate social behaviours, such as mating and fighting, are fundamental to animal reproduction and survival1. However, social engagements can also put an individual at risk2. Little is known about the neural mechanisms that enable appropriate risk assessment and the suppression of hazardous social interactions. Here we identify the posteromedial nucleus of the cortical amygdala (COApm) as a locus required for the suppression of male mating when a female mouse is unhealthy. Using anatomical tracing, functional imaging and circuit-level epistatic analyses, we show that suppression of mating with an unhealthy female is mediated by the COApm projections onto the glutamatergic population of the medial amygdalar nucleus (MEA). We further show that the role of the COApm-to-MEA connection in regulating male mating behaviour relies on the neuromodulator thyrotropin-releasing hormone (TRH). TRH is expressed in the COApm, whereas the TRH receptor (TRHR) is found in the postsynaptic MEA glutamatergic neurons. Manipulating neural activity of TRH-expressing neurons in the COApm modulated male mating behaviour. In the MEA, activation of the TRHR pathway by ligand infusion inhibited mating even towards healthy female mice, whereas genetic ablation of TRHR facilitated mating with unhealthy individuals. In summary, we reveal a neural pathway that relies on the neuromodulator TRH to modulate social interactions according to the health status of the reciprocating individual. Individuals must balance the cost of social interactions relative to the benefit, as deficits in the ability to select healthy mates may lead to the spread of disease.