A pocket-sized disposable device for testing the integrity of sensation in the outpatient setting

Comparing the Ipswich Touch Test (IpTT) and 10gm-SMWF (10-gm Semmes-Weinstein mono-filament) in Indian population subset with type 2 diabetes mellitus to detect diabetes neuropathy

BACKGROUND

Diabetic neuropathy diagnosis involves invasive procedures like nerve biopsy and nerve conduction studies which are seldom available at rural health centers. The Ipswich Touch Test (IpTT) is one test that can be performed by the caregiver and it's simple to perform.

AIM

This study was aimed to compare the validity of the IpTT and 10gm-SMWF (10-gm Semmes-Weinstein mono-filament) test with the vibration perception threshold (VPT) using biothesiometer.

METHODS

Two hundred patients with type 2 diabetes, between the age of 30 and 50 years, were included in the study. The neuropathy assessment was performed by biothesiometer, 10gm-SMWF test, and IpTT. Taking VPT(> 25 V) as the gold standard; the sensitivity and specificity of IpTT and 10gm-SMWF are calculated and compared to each other.

RESULTS

On comparing with the VPT, the 10gm-SMWF test had a sensitivity of 94.7% and specificity of 85.7%, and the IpTT had a sensitivity of 91.9% and specificity of 85.7%. 10gm-SMWF test (Kappa value 0.733) had better agreement with VPT than IpTT (Kappa value 0.675). On Spearman's correlation, the 10gm-SMWF test and the IpTT had r values of 0.738 and 0.686 respectively (P = 0.000).

CONCLUSION

10gm-SMWFis a better test to diagnose neuropathy than the IpTT; but in the absence of 10gm-SMWFs, the IpTT is an ideal alternative. IpTT can be performed in a bedside or chairside setting in the absence of a professional health care provider who can screen patients for neuropathy and alert the physician of an impending complication where amputation can be avoided.

Screening for the loss of protective sensation in people without a history of diabetic foot ulceration: validation of two simple tests in India

The ability of the Ipswich touch test (IpTT) and Vibratip^TM to detect loss of protective sensation (LOPS) was tested against a neurothesiometer in an outpatient diabetic population without a history for ulceration. Our results support the use of the IpTT as a screening tool for LOPS, but not of Vibratip^TM.

The short-term prognosis of diabetic foot ulceration is independent of nutritional status at admission

Diabetic foot ulcers are one of the complications of diabetes. Malnutrition is one of the risk factors for wounds but, on the other hand, diabetic foot ulceration may promote malnutrition. In this single-centre retrospective study we evaluated the frequency of malnutrition at first admission and the severity of foot ulceration. We demonstrated that malnutrition at admission correlated with duration of hospitalisation and with death rate rather than with the risk of amputation. Our data challenged the concept that protein-energy deficiency may worsen the prognosis of diabetic foot ulcers. Nevertheless, it is still important to screen nutritional status at baseline and during the follow-up in order to start specific nutritional support therapy as soon as possible in order to reduce morbidity/mortality related to malnutrition.

The Performance and Interrater Agreement of Vibration Perception for the Diagnosis of Loss of Protective Sensation in People With Diabetes Mellitus

This study examined the performance of VibraTip for the diagnosis of loss of protective sensation (LOPS) and the interrater agreement of different neurological modalities performed by 3 health care professionals, a consultant diabetologist, a diabetes specialist nurse, and a podiatrist. Diagnosis of LOPS was based on 10-g Semmes Weinstein monofilament testing performed by a consultant diabetologist (reference method), while examination with a 128-Hz tuning form was also performed. The performance of VibraTip for the diagnosis of LOPS was examined using the receiver operating characteristic curves analysis. Interrater agreement was determined by weighted kappa (κ) statistics. Diagnosis of LOPS (%) was 37.5%. Receiver operating characteristic curve analysis showed that VibraTip examination versus 10-g monofilament, both performed by a consultant, could diagnose LOPS (P < .001). Sensitivity, specificity, positive predictive value, and negative predictive value of VibraTip versus 10-g monofilament, both performed by a consultant (value, 95% confidence interval), was 0.705 (0.591-0.803), 0.836 (0.758-0.897), 0.733 (0.642-0.808), and 0.816 (0.757-0.863), respectively. The interrater agreement among the health care professionals for 10-g monofilament, VibraTip, and 128-Hz tuning fork in neurological assessment was good with κ > 0.61. VibraTip can be used as a screening tool for the detection of LOPS. There was good overall agreement in the results of neurological examination using 10-g monofilament, 128-Hz tuning fork, and VibraTip among health care professionals.

Peripheral Neuropathy in Diabetes Mellitus: Pathogenetic Mechanisms and Diagnostic Options

Diabetic neuropathy (DN) is one of the main microvascular complications of both type 1 and type 2 diabetes mellitus. Sometimes, this could already be present at the time of diagnosis for type 2 diabetes mellitus (T2DM), while it appears in subjects with type 1 diabetes mellitus (T1DM) almost 10 years after the onset of the disease. The impairment can involve both somatic fibers of the peripheral nervous system, with sensory-motor manifestations, as well as the autonomic system, with neurovegetative multiorgan manifestations through an impairment of sympathetic/parasympathetic conduction. It seems that, both indirectly and directly, the hyperglycemic state and oxygen delivery reduction through the vasa nervorum can determine inflammatory damage, which in turn is responsible for the alteration of the activity of the nerves. The symptoms and signs are therefore various, although symmetrical painful somatic neuropathy at the level of the lower limbs seems the most frequent manifestation. The pathophysiological aspects underlying the onset and progression of DN are not entirely clear. The purpose of this review is to shed light on the most recent discoveries in the pathophysiological and diagnostic fields concerning this complex and frequent complication of diabetes mellitus.

Interprofessional Validation of the Ipswich Touch Test in Adults With Diabetes: The Canadian Experience

OBJECTIVES

Diabetes can lead to loss of protective sensation (LOPS) in the feet. Identifying LOPS requires use of screening tests, such as the standard monofilament test (SMT) and the Ipswich Touch Test (IpTT). The aim of this validation study was to compare the SMT (criterion) with the IpTT (new test).

METHODS

Each participant was randomly tested using the SMT, IpTT and Neuropathy Disability Score to identify LOPS. Sixteen health-care providers assessed 8 participants in randomized order using a specific protocol.

RESULTS

The IpTT, compared with the SMT, demonstrated a specificity of 100% for all raters and a mean sensitivity of 93.8% for LOPS. Kappa coefficient was 0.97 for SMT and 0.83 for IpTT.

CONCLUSIONS

The IpTT can be used by health-care providers as an effective tool for screening for LOPS in people with diabetes. This study validated the IpTT to the SMT in identifying LOPS.

Application of the Ipswich Touch Test for diabetic peripheral neuropathy screening: a systematic review and meta-analysis

OBJECTIVE

Diabetic peripheral neuropathy (DPN) is one of the most important risk factors of diabetic foot ulcers, and early screening and treatment of DPN are crucial. The Ipswich Touch Test (IPTT) is a new method for screening for DPN and, compared with traditional methods, is more simple to operate and requires no equipment. However, the screening accuracy of IPTT in patients with DPN has not been well characterised. We aim to conduct a systematic review and meta-analysis to characterise the sensitivity and specificity of IPTT compared with traditional methods and to understand the potential screening value of IPTT.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

PubMed, Embase, Cochrane Library, Web of Science, China National Knowledge Infrastructure, Wanfang, Chinese Biomedical Literature Database up to 16 April 2020.

METHODS

Stata V.15.1 software was used for analysis, and the screening value of IPTT in DPN was described using 10 g monofilament (10g-MF), neuropathy disability scores (NDS), Pin prick, 128 Hz tuning fork, and ankle reflex as reference standards. Sensitivity, specificity and other measures of accuracy of IPTT for screening DPN were pooled based on a quality effects model. The protocol was registered with PROSPERO (42020168420).

RESULTS

Of the 441 records retrieved, 7 studies were evaluated for the screening value of IPTT. Five studies with 10g-MF as the reference standard were included in the meta-analysis, and the pooled sensitivity and specificity were 0.77 (95％CI 0.69-0.84) and 0.96(95％CI 0.93-0.98), respectively, and the area under curve was 0.897. Compared with vibration perception threshold, IPTT showed a sensitivity between 0.76 and 1, and a specificity between 0.90 and 0.97. Compared with NDS, IPTT showed a sensitivity between 0.53 and 1, and a specificity between 0.90 and 0.97. Compared with Pin prick, IPTT showed a sensitivity and specificity of 0.8 and 0.88, respectively. Compared with 128 Hz tuning fork, IPTT showed a sensitivity and specificity of 0.4 and 0.27, respectively. Compared with ankle reflex, IPTT had a sensitivity of 0.2 and a specificity of 0.97.

CONCLUSIONS

IPTT shows a high degree of agreement with other commonly used screening tools for DPN screening. It can be used clinically, especially in remote areas and in primary medical institutions, and by self-monitoring patients. More high-quality studies are needed to assess and promote more effective screening practices.

PROSPERO REGISTRATION NUMBER

Registration Number is CRD (42020168420).

Comparison of Clinical Tests for Peripheral Diabetic Neuropathy in a Type 1 Diabetes Cohort

OBJECTIVE

To examine the performance and agreement of 5 modalities for testing sensory neuropathy against a neurothesiometer among Hispanic patients with type 1 diabetes (T1D) in an outpatient setting.

METHODS

A cross-sectional study was conducted at a tertiary reference center in Mexico City. Sensitivity, specificity, predictive values, and likelihood ratios were calculated using a VibraTip device, 128 Hz tuning fork, and the Semmes-Weinstein 5.07/10 g monofilament test, Ipswich touch test (IpTT), and pinprick test (PPT). The VPT obtained using a neurothesiometer was used as the standard. Agreement between tests was calculated using kappa coefficients.

RESULTS

Our study included 78 patients (156 examinations), of whom 56.4% were females. The mean age was 38.2 ± 13.0 years, and the mean body mass index was 24.6 ± 4.8 kg/m². The best sensitivity was found for IpTT and VibraTip (89.7% and 79.3%, respectively), while the PPT and IpTT had the highest positive predictive values (94.4% and 92.9%, respectively). The highest kappa coefficients were obtained for the IpTT vs neurothesiometer (kappa coefficient [κ] = 0.893, P < .001), followed by VibraTip vs neurothesiometer (κ = 0.782, P < .001). The VibraTip vs IpTT also had a substantial agreement (κ= 0.713, P < .001).

CONCLUSION

Our findings demonstrated that the IpTT had the best diagnostic performance and agreement compared with the standard in this cohort of Hispanic patients with T1D. The IpTT is a useful, simple test for diabetic neuropathy screening. These findings support its inclusion in future guidelines for diabetic foot examination.

Diabetic neuropathy in children and youth: New and emerging risk factors

Pediatric neuropathy attributed to metabolic dysfunction is a well-known complication in children and youth with type 1 diabetes. Moreover, the rise of obesity and in particular of type 2 diabetes may cause an uptick in pediatric neuropathy incidence. However, despite the anticipated increase in neuropathy incidence, pathogenic insights and strategies to prevent or manage neuropathy in the setting of diabetes and obesity in children and youth remain unknown. Data from adult studies and available youth cohort studies are providing an initial understanding of potential diagnostic, management, and preventative measures in early life. This review discusses the current state of knowledge emanating from these efforts, with particular emphasis on the prevalence, clinical presentation, diagnostic approaches and considerations, and risk factors of neuropathy in type 1 and type 2 diabetes in children and youth. Also highlighted are current management strategies and recommendations for neuropathy in children and youth with diabetes. This knowledge, along with continued and sustained emphasis on identifying and eliminating modifiable risk factors, completing randomized controlled trials to assess effectiveness of strategies like weight loss and exercise, and enhancing awareness to support early detection and prevention, are pertinent to addressing the rising incidence of neuropathy associated with diabetes and obesity in children and youth.

Evaluation of the accuracy of vibration sense with VibraTip™ as a tool to determine the level of anesthesia following subarachnoid block and its correlation with the pinprick sensation

BACKGROUND AND AIMS

Assessment of level of anesthesia after subarachnoid block (SAB) is essential. We aimed to evaluate the efficacy of vibration sense as a criteria to determine the level of surgical anesthesia.

METHOD AND MATERIALS

The study included patients, scheduled for various surgeries under SAB. The baseline values of vibration sense perception using VibraTip™, motor power using the modified Bromage scale, and sensory block by pinprick method were recorded preoperatively and at 5 and 7 min after administration of SAB. The correlation between vibration sense, loss of pinprick sensation, and level of anesthesia were assessed.

RESULTS

The concordance correlation coefficient between the pinprick and vibration sense at 5 min and 7 min showed poor strength of agreement with Pearson ρ (precision) being 0.4192 at 5 min and 0.4701 at 7 min.

CONCLUSION

Vibration sense serves as a reliable indicator to assess the level of surgical anesthesia following SAB. Vibration sense testing with VibraTip™along with motor power assessment can be used as a tool for assessment of level of block. There is a poor correlation between level of vibration sense and pinprick.

Facial erythema detects diabetic neuropathy using the fusion of machine learning, random matrix theory and self organized criticality

Rubeosis faciei diabeticorum, caused by microangiopathy and characterized by a chronic facial erythema, is associated with diabetic neuropathy. In clinical practice, facial erythema of patients with diabetes is evaluated based on subjective observations of visible redness, which often goes unnoticed leading to microangiopathic complications. To address this major shortcoming, we designed a contactless, non-invasive diagnostic point-of-care-device (POCD) consisting of a digital camera and a screen. Our solution relies on (1) recording videos of subject's face (2) applying Eulerian video magnification to videos to reveal important subtle color changes in subject's skin that fall outside human visual limits (3) obtaining spatio-temporal tensor expression profile of these variations (4) studying empirical spectral density (ESD) function of the largest eigenvalues of the tensors using random matrix theory (5) quantifying ESD functions by modeling the tails and decay rates using power law in systems exhibiting self-organized-criticality and (6) designing an optimal ensemble of learners to classify subjects into those with diabetic neuropathy and those of a control group. By analyzing a short video, we obtained a sensitivity of 100% in detecting subjects diagnosed with diabetic neuropathy. Our POCD paves the way towards the development of an inexpensive home-based solution for early detection of diabetic neuropathy and its associated complications.

A review of the current evidence on the sensitivity and specificity of the Ipswich touch test for the screening of loss of protective sensation in patients with diabetes mellitus

Aims

To evaluate the sensitivity and specificity of the Ipswich touch test for the screening of loss of protective sensation in patients with diabetes mellitus based on the current literature.

Methods

Three electronic databases were searched for eligible studies that investigated the sensitivity and specificity of the Ipswich touch test. Methodological quality was assessed using the QUADAS-2 tool.

Results

Five studies that reported the sensitivity and specificity of the Ipswich touch test were included. When compared to the 10 g monofilament, the sensitivity ranges from 51 to 83.3% and the specificity ranges from 96.4 to 98%. When compared to the vibration perception test ≥25 V, Ipswich touch test sensitivity ranges from 76 to 100% and specificity ranges from 90 to 96.6%.

Conclusions

The Ipswich touch test has a high specificity in screening for loss of protective sensation in the feet of patients with diabetes mellitus. It is a useful test to be included in diabetic foot screenings, especially when other sensory tools are not available. However, more rigorous studies need to be conducted as there is currently only a limited pool of research evidence to substantiate it as a screening tool for loss of protective sensation in the diabetic foot.

The Diagnostic Utility of VibraTip for Distal Symmetrical Polyneuropathy in Type 2 Diabetes Mellitus

INTRODUCTION

The aim of this study was to assess the performance of VibraTip, a device used to test a person's vibration perception during routine checks for peripheral neuropathy, against two thresholds of the Neuropathy Disability Score (NDS) for diagnosing distal symmetrical polyneuropathy (DSPN) in patients with type 2 diabetes mellitus (T2DM).

METHODS

One hundred consecutive subjects with T2DM were enrolled in the study, of whom 54 were men. The mean age was 62.3 years, and the mean T2DM duration was 12.6 years. VibraTip was used at one foot site (on the pulp of the hallux; protocol A) and at three foot sites (pulp of the hallux and first and third metatarsal head; protocol B). NDS thresholds of  ≥ 3 and ≥ 6 were used to establish the diagnosis of DSPN.

RESULTS

Against the NDS ≥ 3 threshold, VibraTip showed a very high sensitivity (91.3%) and negative predictive value (NPV) (92%) and a high specificity (85.2%) with protocol A, and a very high sensitivity (95.6%) and NPV (96.1%) and a very high specificity (90.7%) with protocol B. Against the NDS ≥ 6 threshold, VibraTip showed a very high sensitivity (100%) and NPV (100%) and a very high specificity (95.2%) with protocol A, and very high sensitivity (100%) and NPV (100%) and very high specificity (96.8%) with protocol B.

CONCLUSIONS

The diagnostic performance of VibraTip is very high in patients with T2DM, rendering it a very useful device as a screening tool, particularly for the exclusion of DSPN. VibraTip performs very well at both NDS thresholds, but particularly well at the NDS ≥ 6 threshold. There appears to be no need to examine sites other than the hallux site with Vibratip.

Diabetic peripheral neuropathy: advances in diagnosis and strategies for screening and early intervention

Diabetic peripheral neuropathy (DPN) is a common complication of both type 1 and 2 diabetes. It is a leading cause of lower-limb amputation and disabling neuropathic pain. Amputations in patients with diabetes have a devastating effect on quality of life and are associated with an alarmingly low life expectancy (on average only 2 years from the amputation). Amputation also places a substantial financial burden on health-care systems and society in general. With the introduction of national diabetes eye screening programmes, the prevalence of blindness in working-age adults is falling. This is not the case, however, with diabetes related amputations. In this Review, we appraise innovative point-of-care devices that enable the early diagnosis of DPN and assess the evidence for early risk factor-based management strategies to reduce the incidence and slow the progression of DPN. We also propose a framework for screening and early multifactorial interventions as the best prospect for preventing or halting DPN and its devastating sequelae.

Comparing the Diagnostic Accuracy of Simple Tests to Screen for Diabetic Peripheral Neuropathy: Protocol for a Cross-Sectional Study

Background

Various tests are used to detect diabetic peripheral neuropathy by assessing sense perception in the feet. Tests vary in terms of time and resources required. Simple tests are those that can be conducted quickly and easily in primary care without laboratory equipment. There are some limitations to these simple tests, an example being the variable amplitude of the 128 Hz tuning fork. A new test, VibraTip (McCallan Medical, UK), might be a valuable alternative as it emits a consistent amplitude and may offer improved diagnostic accuracy.

Objective

The aims of this study are to estimate the diagnostic accuracy of the VibraTip device for diabetic peripheral neuropathy against the reference standard of sural nerve conduction velocity measurement, and to assess whether the VibraTip offers superior diagnostic accuracy to other routine tests based on vibration or touch.

Methods

The study will prospectively recruit adults with type 2 diabetes who are due to attend a routine follow-up clinic. A cross-sectional study design will be employed to assess the diagnostic accuracy of 5 standard index tests for peripheral neuropathy, including VibraTip. The reference test will be sural nerve conduction velocity measurement.

Results

Funding is being sought to conduct this research. The outcomes assessed will be the diagnostic accuracy of the 5 index tests against sural nerve conduction velocity measurement, including sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, and negative likelihood ratio. Receiver operating characteristic curves will be constructed and compared for each test.

Conclusions

This study will be the first within-study comparison of 5 simple tests for screening diabetic peripheral neuropathy and will address uncertainties in the potential benefits of using VibraTip in comparison with the other tests.

Early detection of neuropathy in leprosy: a comparison of five tests for field settings

Background

Early detection and treatment of neuropathy in leprosy is important to prevent disabilities. A recent study showed that the Nerve Conduction Studies (NCS) and Warm Detection Thresholds (WDT) tests can detect leprosy neuropathy the earliest. These two tests are not practical under field conditions, however, because they require climate-controlled rooms and highly trained staff and are expensive. We assessed the usefulness of alternative test methods and their sensitivity and specificity to detect neuropathy at an early stage.

Methods

Through a literature search we identified five alternative devices that appeared user-friendly, more affordable, portable and/or battery-operated: the Neuropad®, Vibratip™, NC-Stat®DPNCheck™, NeuroQuick and the Thermal Sensibility Tester (TST), assessing respectively sweat function, vibration sensation, nerve conduction, cold sensation and warm sensation. In leprosy patients in Bangladesh, the posterior tibial and sural nerves that tested normal for the monofilament test and voluntary muscle test were assessed with the NCS and WDT as reference standard tests. The alternative devices were then tested on 94 nerves with abnormal WDT and/or NCS results and on 94 unaffected nerves. Sensitivity and specificity were the main outcomes.

Results

The NeuroQuick and the TST showed very good sensitivity and specificity. On the sural nerve, the NeuroQuick had both a sensitivity and a specificity of 86%. The TST had a sensitivity of 83% and a specificity of 82%. Both the NC-Stat®DPNCheck™ and Vibratip™ had a high specificity (88% and 100%), but a low sensitivity (16% and 0%). On the posterior tibial nerve, the NeuroQuick and the TST also showed good sensitivity, but the sensitivity was lower than for the sural nerve. The Neuropad® had a sensitivity of 56% and a specificity of 61%.

Conclusions

The NeuroQuick and TST are good candidates for further field-testing for reliability and reproducibility. The feasibility of production on a larger scale should be examined.

Electronic supplementary material

The online version of this article (doi:10.1186/s40249-017-0330-2) contains supplementary material, which is available to authorized users.

Screening tests for distal symmetrical polyneuropathy in Latin American patients with type 2 diabetes mellitus

OBJECTIVE

This cross sectional study intended to evaluate two bedside tests (Neuropad and VibraTip) as screening tools for distal symmetrical polyneuropathy (DSPN) in Latin American patients with type 2 diabetes mellitus (T2D).

SUBJECTS AND METHODS

Ninety-three Colombian patients diagnosed with T2D were recruited. Anthropometric variables, glycemic control parameters, lipid profile and renal function were assessed for each patient. DSPN was defined by a Michigan Neuropathy Screening Instrument (MNSI) clinical score greater than 2. Both Neuropad and Vibratip tests were applied to each patient. Contingency analyses were performed to evaluate the diagnostic power of both tools.

RESULTS

The prevalence of DSPN determined clinically by MNSI was 25.8%. DSPN in these patients was associated with age, worsening renal function, and insulin treatment. The sensitivity and specificity of the Neuropad test for DSPN was 66.6% and 63% respectively. Its negative predictive value (NPV) was 84.6%. The VibraTip test exhibited a sensitivity of 54.1% and specificity of 91.3%, with a NPV of 85.1%.

CONCLUSION

Neuropad and VibraTip are reliable screening tools for DSPN in Latin American population. VibraTip presents a considerable diagnostic power for DSPN in this population. Further studies regarding the cost-effectiveness of these tools in clinical practice are needed.

SUDOSCAN: A Simple, Rapid, and Objective Method with Potential for Screening for Diabetic Peripheral Neuropathy

Clinical methods of detecting diabetic peripheral neuropathy (DPN) are not objective and reproducible. We therefore evaluated if SUDOSCAN, a new method developed to provide a quick, non-invasive and quantitative assessment of sudomotor function can reliably screen for DPN. 70 subjects (45 with type 1 diabetes and 25 healthy volunteers [HV]) underwent detailed assessments including clinical, neurophysiological and 5 standard cardiovascular reflex tests (CARTs). Using the American Academy of Neurology criteria subjects were classified into DPN and No-DPN groups. Based on CARTs subjects were also divided into CAN, subclinical-CAN and no-CAN. Sudomotor function was assessed with measurement of hand and foot Electrochemical Skin Conductance (ESC) and calculation of the CAN risk score. Foot ESC (μS) was significantly lower in subjects with DPN [n = 24; 53.5(25.1)] compared to the No-DPN [77.0(7.9)] and HV [77.1(14.3)] groups (ANCOVA p<0.001). Sensitivity and specificity of foot ESC for classifying DPN were 87.5% and 76.2%, respectively. The area under the ROC curve (AUC) was 0.85. Subjects with CAN had significantly lower foot [55.0(28.2)] and hand [53.5(19.6)] ESC compared to No-CAN [foot ESC, 72.1(12.2); hand ESC 64.9(14.4)] and HV groups (ANCOVA p<0.001 and 0.001, respectively). ROC analysis of CAN risk score to correctly classify CAN revealed a sensitivity of 65.0% and specificity of 80.0%. AUC was 0.75. Both foot and hand ESC demonstrated strong correlation with individual parameters and composite scores of nerve conduction and CAN. SUDOSCAN, a non-invasive and quick test, could be used as an objective screening test for DPN in busy diabetic clinics, insuring adherence to current recommendation of annual assessments for all diabetic patients that remains unfulfilled.

Preventing and treating foot complications associated with diabetes mellitus

Diabetes mellitus is associated with a series of macrovascular and microvascular changes that can manifest as a wide range of complications. Foot ulcerations affect ∼2-4% of patients with diabetes mellitus. Risk factors for foot lesions include peripheral and autonomic neuropathy, vascular disease and previous foot ulceration, as well as other microvascular complications, such as retinopathy and end-stage renal disease. Ulceration is the result of a combination of components that together lead to tissue breakdown. The most frequently occurring causal pathways to the development of foot ulcers include peripheral neuropathy and vascular disease, foot deformity or trauma. Peripheral vascular disease is often not diagnosed in patients with diabetes mellitus until tissue loss is evident, usually in the form of a nonhealing ulcer. Identification of patients with diabetes mellitus who are at high risk of ulceration is important and can be achieved via annual foot screening with subsequent multidisciplinary foot-care interventions. Understanding the factors that place patients with diabetes mellitus at high risk of ulceration, together with an appreciation of the links between different aspects of the disease process, is essential to the prevention and management of diabetic foot complications.

Distal Sensorimotor Neuropathy: Improvements in Diagnosis

Neurological complications of diabetes are common, affecting up to 50% of people with diabetes. In these patients, diabetic sensorimotor neuropathy (DSPN) is by far the most frequent complication. Detecting DSPN has traditionally been a clinical exercise that is based on signs and symptoms. However, the appearance of morphometric and neurophysiological techniques along with composite scoring systems and new screening tools has induced a paradigm change in the detection and stratification of DSPN and our understanding of its natural history and etiopathogenesis. These newer techniques have provided further evidence that changes in small nerve fiber structure and function precede large fiber changes in diabetes. Although useful, the challenge for the use of these new techniques will be their sensitivity and specificity when widely adopted and ultimately, their ability to demonstrate improvement when pathogenic mechanisms are corrected. Concurrently, we have also witnessed an emergence of simpler screening tools or methods that are mainly aimed at quicker detection of large fiber neuropathy in the outpatient setting. In this review, we have focused on techniques and tools that receive particular attention in the current literature, their use in research and potential use in the clinical environment.

ViibraTip for Testing Vibration Perception to Detect Diabetic Peripheral Neuropathy: A NICE Medical Technology Guidance

VibraTip™ was selected by the Medical Technologies Advisory Committee (MTAC) to undergo evaluation through the National Institute for Health and Care Excellence (NICE). VibraTip™ provides a vibratory stimulus for the purpose of detecting diabetic peripheral neuropathy (DPN) in patients with type 1 or 2 diabetes mellitus, and is intended to replace the current practice of using the 128 Hz tuning fork or 10 g monofilament (comparators). The sponsor (McCallan Medical) provided clinical and economic submissions which were evaluated by an External Assessment Centre (EAC). Of six diagnostic studies identified, the EAC considered that only one was directly relevant to the assessment. This study indicated VibraTip™ had a sensitivity of 0.79 (95 % CI 0.69-0.90) and specificity of 0.82 (95 % CI 0.74-0.90) for DPN using a neurothesiometer at 25 V as a reference standard. This was non-inferior to the comparators, but the sample size (n = 141) was too small to draw unequivocal conclusions and it is unclear how generalisable results were to clinical practice. The sponsor presented a de facto cost-minimisation model that in the base case showed minimal cost savings and, in sensitivity analysis which assumed diagnostic superiority of VibraTip™, showed large savings. The EAC appraised this model and concluded it was flawed as it was not evidence based and costs were likely to be unrealistic. The MTAC considered that the technology showed promise but decided the case for adoption was not proven, and therefore made a research recommendation as is reflected in NICE Medical Technology Guidance 22.

Utilizing the Ipswich Touch Test to simplify screening methods for identifying the risk of foot ulceration among diabetics: The Saudi experience

Our study demonstrates that Ipswich Touch Test is reliable and comparable to established standardized tests that identify the risk of foot ulceration among Saudi patients with diabetes mellitus. The simplicity of the test will assist in overcoming the barriers to screen for and detect the risk of foot ulceration.

New vistas in the diagnosis of diabetic polyneuropathy

New modalities are now available to improve the diagnosis of diabetic polyneuropathy (DPN). The present review discusses the progress achieved in this area. First, the minimal diagnostic criteria have been better clarified. Moreover, there are now new bedside tests available, such as the indicator test Neuropad, NeuroQuick, Ipswich Touch Test (IpTT), Vibratip, NC-stat(®)/DPNCheck™ for automated nerve conduction study (NCS), tactile circumferential discriminator, steel ball-bearing, and SUDOSCAN(®), while more sophisticated modalities include skin biopsy and corneal confocal microscopy (CCM). Some tests can be used as screening tools, including primary care setting (Neuropad, IpTT, Vibratip, automated NCS), while others are more suitable for research, including evaluation of DPN in prospective studies (CCM, skin biopsy). Importantly, there is some evidence of earlier DPN diagnosis with the aid of some tests (Neuropad, skin biopsy, CCM). Further advantages provided by different tests are educational value and self-examination. Thus far, the potential of these tests has not been fully utilised. In particular, they have not been validated against standardised clinical examination scores in terms of predicting foot ulcers and amputations. Hence, it now remains to investigate the potential benefits from the widespread use of these tests for earlier and easier diagnosis of DPN in the everyday clinic.

Diabetic neuropathy and foot complications

Foot ulceration and Charcot neuroarthropathy (CN) are well recognized and documented late sequelae of diabetic peripheral, somatic, and sympathetic autonomic neuropathy. The neuropathic foot, however, does not ulcerate spontaneously: it is a combination of loss of sensation due to neuropathy together with other factors such as foot deformity and external trauma that results in ulceration and indeed CN. The commonest trauma leading to foot ulcers in the neuropathic foot in Western countries is from inappropriate footwear. Much of the management of the insensate foot in diabetes has been learned from leprosy which similarly gives rise to insensitive foot ulceration. No expensive equipment is required to identify the high risk foot and recently developed tests such as the Ipswich Touch Test and the Vibratip have been shown to be useful in identifying the high risk foot. A comprehensive screening program, together with education of high risk patients, should help to reduce the all too high incidence of ulceration in diabetes. More recently another very high risk group has been identified, namely patients on dialysis, who are at extremely high risk of developing foot ulceration; this should be preventable. The most important feature in management of neuropathic foot ulceration is offloading as patients can easily walk on active foot ulcers due to the loss of pain sensation. Infection should be treated aggressively and if there is any evidence of peripheral vascular disease, arteriography and appropriate surgical management is also indicated. CN often presents with a unilateral hot, swollen foot and any patient presenting with these features known to have neuropathy should be treated as a Charcot until this is proven otherwise. Most important in the management of acute CN is offloading, often in a total contact cast.

The pathway to foot ulceration in diabetes

It should now be possible to achieve a reduction in the incidence of foot ulceration and amputations as knowledge about pathways that result in both these events increases. However, despite the universal use of patient education and the hope of reducing the incidence of ulcers in high-risk patients, there are no appropriately designed large, randomized controlled trials actually confirming that education works. It has been recognized for some years that education as part of a multidisciplinary approach to care of the diabetic foot can help to reduce the incidence of amputations in certain settings. Ultimately, however, a reduction in neuropathic foot problems will only be achieved if we remember that the patients with neuropathic feet have lost their prime warning signal—pain—that ordinarily brings patients to their doctor. Very little training is offered to health care professionals as to how to deal with such patients. Much can be learned about the management of such patients from the treatment of individuals with leprosy: if we are to succeed, we must realize that with loss of pain there is also diminished motivation in the healing of and prevention of injury.

VibraTip® durability in clinical practice: how long does it last?

VibraTip® is a battery-powered, disposable, key fob-sized source of vibration used to assess the integrity of vibration perception. To find out how long the device lasts, the stability of its vibration output was measured in response to two usage patterns:-

in the first, VibraTip® was subject to 7000 half second activations separated by 2 second rests. This yielded fairly consistent frequency output for the first 6000 activations but an early reduction in amplitude over the first 1000 activations, steadying between 2000 and 6000 activations.

in the second, designed to mimic more closely real life clinical usage, runs of ten, half second activations at 2 second intervals were interspersed by 10 minute rests. The cycle was repeated 350 times in all with additional overnight rests to allow electrochemical recovery. VibraTip® performance under these conditions was highly consistent over at least the first 1500 activations, with very little change in vibration frequency even after 3500 discharges.

These results indicate that usage patterns markedly affect VibraTip® durability. Rests between ‘patients’ and overnight, characteristic of normal clinical activity, suggests that VibraTip® is likely to provide very consistent performance in the clinical arena for many months of routine use.