Association of verrucous skin lesions and skin ulcers on the feet in patients with diabetic neuropathy

A smart wearable device for monitoring and self-management of diabetic foot: A proof of concept study

BACKGROUND AND OBJECTIVE

Diabetic foot is one of the important complications of diabetes, which is occurred due to the destructive parameters in different anatomical sites of feet. Management and monitoring of these parameters are very important to decrease or prevent foot ulcers. We aimed to develop a smart wearable device to monitor these parameters to prevent diabetic foot.

METHODS

Following literature review and expert panel discussions, we considered pressure, temperature and humidity to develop the system. During these sessions, we also developed the system architecture and determined the required technologies. We also developed a mobile application. Finally, all sensors were evaluated for accurate monitoring of pressure, temperature and humidity. A standard protocol was used to evaluate each of these sensors. To this end, five people (four with diabetes and one healthy person) participated. They did a series of movements including walking, sitting, and standing. We considered the pressure measured by Pedar system as the gold standard. Furthermore, we changed the environment temperature and humidity during several experiments and considered the environment temperature and humidity as gold standard. We compared the measured values by sensors with these gold standards.

RESULTS

The evaluation indicated the accurate performance of pressure, humidity and temperature sensors. Sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the system to provide alarms based on the pressure measured using Pedar were 100, 50, 92.5, 91.8, and 100 %, respectively. The performance of temperature sensors in smart shoes was confirmed by slight differences compared to thermometers. Relatively equal values of humidity measured by two sensors on the left and right feet and the increased difference with the environment humidity showed the exact humidity measured using these sensors.

CONCLUSION

This smart shoes monitors pressure, humidity, and temperature of patients' feet and sends this data to their smart phone by the Bluetooth module. Furthermore, it controls these parameters; as each of these parameters exceeds the defined threshold, alerts are given to patients for self-management.

Monitoring of external predisposing factors for Diabetic Foot: A literature review and physicians' perspectives

Background: Diabetic foot is one of the most important complications of diabetes caused by the existence of some destructive factors in different anatomical locations of feet. Management and monitoring of these factors are very important to decrease or avoid ulcerating lesions of the foot. The purpose of this study is to identify and introduce the predisposing factors and anatomical locations associated with these destructive factors. Methods: First, we conducted a comprehensive review of different databases to identify the factors and associated anatomical locations from the previous studies. Then, we designed a questionnaire and invited physicians and specialists to express their perspectives on these factors and locations. The data were analyzed using SPSS version 23. Frequency, percentage, mean and standard deviation of these variables were calculated. Results: Based on the literature review, four factors, including pressure, moisture and sweat, temperature, and acceleration were identified as factors destructive to the tissues of the diabetic foot and worsen ulcers. The view of specialists approved the results of the literature review. Besides, there was an insignificant difference between the results of the literature review and the specialists' view in terms of anatomical locations that need to be continuously monitored. Conclusion: Monitoring the pressure in heel, first metatarsal, and first metatarsal head; moisture and sweat under the fingers, hallux and heels as well as the temperature at the first metatarsal, first metatarsal head, and the third metatarsal head are important in preventing ulceration, destructing the foot tissue, and accelerating the treatment process.

Verrucous lesions arising in lymphedema and diabetic neuropathy: Elephantiasis nostras verrucosa or verrucous skin lesions on the feet of patients with diabetic neuropathy?

Verrucous skin lesions on the feet in diabetic neuropathy (VSLDN) develop in areas with sensory loss in diabetic patients. Although various types of chronic stimulation, such as pressure or friction, are considered an important factor in the development of such lesions, the precise pathogenesis of VSLDN remains obscure, and there is currently no established treatment for this disease. Here, we present a case of VSLDN on the dorsum of the right foot. However, because lymphedema was also observed at the same site, this lesion could also be diagnosed as elephantiasis nostras verrucosa arising in diabetic neuropathy. The lesion was successfully treated with a combination of elastic stocking and mixed killed bacterial suspension and hydrocortisone ointment, which suggested that VSLDN might have been exacerbated by the pre-existing lymphedema. Because various types of chronic stimulation can trigger VSLDN, treatment plans should be devised on a case-by-case basis. Therefore, it is important to investigate the presence of factors that can induce or exacerbate chronic inflammatory stimulation, such as lymphedema in our case, in each patient with VSLDN.