(Invited) Point-of-Care Based System Development for Urolithiasis Recurrence Prevention

Abstract

Point-of-care (POC) based system becomes more important for aging society and modern life. In Taiwan or globally, most of patients who have a history of urinary stone, the chance of recurrence is about 70 – 80% within 7 years. So, the cost of urinary stone treatment consumes a significant percent of health care insurance. A platform for measuring key parameters of morning spot urine (random urine) to predict the onset of urolithiasis was implemented in this study. This research presents a POC test system developed for urolithiasis recurrence prevention. The system can be used to assist a patient in assessing the condition of his urinary system through urine quality indicators pH, Ca2+, uric acid, conductivity, color and crystallization, etc. Several major types of sensors were used to monitor core parameters in human’s urine. Ion Sensitive Field Effect Transistor and Extended Gate Field Effect Transistor potentiometric-type sensors are used for pH and Ca2+ monitoring, the enzyme based two or three-electrode amperometric type sensor is used for urine’s uric acid sensing, and the self-developed electrodes are used for conductivity measuring. The wireless based prototype with these sensors and CMOS readout circuits were integrated and tested in the laboratory and clinically. In this research, the integrated circuit designs for sub-sensing system implementation were fabricated through TSMC 0.35um and 0.18um CMOS processes. The test results on key parameters monitored by the proposed prototype and fabricated integrated circuits show an acceptable and promising performance referred to corresponding commercial meters for individual parameter sensing. In addition, the prototype system with blue tooth transceiver was developed for wireless communication. Through the data analysis and risk assessment made by urologists, this system can provide a regular urine quality monitoring to patients with urinary stone, the eating and life styles can be consulted or adjusted according to the data base collected from the proposed system and patient individually. The development of this POCT platform will be also useful for improving the life quality of patient with urolithiasis, extending applications in aging societies and reducing an unnecessary cost of health care insurance. Figure 1