Development of A Rapid, Low-Cost Portable Detection Assay for Enterococci in Wastewater and Environmental Waters

Waterborne diseases are known as a leading cause of illness and death in both developing and developed countries. Several pathogens can be present in contaminated water, particularly waters containing faecal material; however, routine monitoring of all pathogens is not currently possible. Enterococcus faecalis, which is present in the microflora of human and animals has been used as a faecal indicator in water due to its abundance in surface water and soil. Accurate and fast detection methods are critical for the effective monitoring of E. faecalis in the environment. Although conventional and current molecular detection techniques provide sufficient sensitivity, specificity and throughput, their use is hampered by the long waiting period (1-6 days) to obtain results, the need for expensive laboratory equipment, skilled personnel, and cold-chain storage. Therefore, this study aimed to develop a detection system for E. faecalis that would be simple, rapid, and low-cost, using an isothermal DNA amplification assay called recombinase polymerase amplification (RPA), integrated with a lateral flow assay (LFA). The assay was found to be 100% selective for E. faecalis and capable of detecting rates as low as 2.8 × 10³ cells per 100 mL from water and wastewater, and 2.8 × 10⁴ cells per 100 mL from saline water. The assay was completed in approximately 30 min using one constant temperature (38 °C). In addition, this study demonstrated the quantitation of E. faecalis using a lateral flow strip reader for the first time, enhancing the potential use of RPA assay for the enumeration of E. faecalis in wastewater and heavily contaminated environmental waters, surface water, and wastewater. However, the sensitivity of the RPA-LFA assay for the detection of E. faecalis in tap water, saline water and in wastewater was 10-1000 times lower than that of the Enterolert-E test, depending on the water quality. Nevertheless, with further improvements, this low-cost RPA-LFA may be suitable to be used at the point-of-need (PON) if conjugated with a rapid field-deployable DNA extraction method.

The economic impact of flexible endoscopy in a large academic surgical department

BACKGROUND

There has been considerable controversy concerning the value added to a general surgery practice when flexible gastrointestinal endoscopy is incorporated. The purpose of this study was to assess the economic impact of flexible endoscopy performed by general surgeons in a large academic practice.

METHODS

A retrospective review of gross billing charges for a group practice of 11 surgeons over the fiscal year 1999 was performed at the Cleveland Clinic Foundation. The total billing for clinic visits and outpatient and inpatient surgical procedures was compiled, and the percentage attributable to flexible endoscopy was determined. Of the 11 surgeons, three had incorporated flexible endoscopy into their practice.

RESULTS

The three endosurgeons generated 33% of the total gross billing for the Department of General Surgery. Flexible endoscopy alone accounted for 12.2% of the total percentage of gross billings for the department. Meanwhile, this revenue was generated from only 8% of the workweek when performing flexible endoscopic procedures were performed.

CONCLUSION

Flexible endoscopy can contribute significantly to the financial productivity of the general surgeon.

Cost-effectiveness of ambulatory laparoscopic cholecystectomy

The merits of laparoscopic cholecystectomy include faster recovery, less postoperative pain, earlier return to work, and decreased cost. However, there are few economic data comparing laparoscopic cholecystectomy in an ambulatory versus overnight stay setting. In a 12-month period, 74 consecutive cholecystectomies were performed laparoscopically by one surgeon. The ambulatory group consisted of 36 patients who were discharged from the hospital the same day after a mean recovery time of 5 hours (range, 2.25-10.33). Of the remaining 38 patients, 19 were admitted after surgery on 23-hour observation status, and 19 were inpatients. The average hospital cost was significantly less in the ambulatory group than in the observation group, with an 11% mean reduction in cost per patient (P = 0.0061). No patient in either group was readmitted to the hospital within 30 days of surgery. Laparoscopic cholecystectomy can be performed safely in an outpatient setting. The cost savings of ambulatory care versus observation are clearly shown in this study.