Singhan T.M. Krishnan

Reduction in Diabetic Amputations Over 11 Years in a Defined U.K. Population: Benefits of multidisciplinary team work and continuous prospective audit

OBJECTIVE—To assess changes in diabetic lower-extremity amputation rates in a defined relatively static population over an 11-year period following the introduction of a multidisciplinary foot team. RESEARCH DESIGN AND METHODS—All diabetic patients with foot problems admitted to Ipswich Hospital, a large district general hospital, were identified by twice-weekly surveillance of all relevant in-patient areas and outcomes including amputations recorded. RESULTS—The incidence of major amputations fell 62%, from 7.4 to 2.8 per 100,000 of the general population. Total amputation rates also decreased (40.3%) but to a lesser extent due to a small increase in minor amputations. Expressed as incidence per 10,000 people with diabetes, total amputations fell 70%, from 53.2 to 16.0, and major amputations fell 82%, from 36.4 to 6.7. CONCLUSIONS—Significant reductions in total and major amputation rates occurred over the 11-year period following improvements in foot care services including multidisciplinary team work.

Reduction in diabetic amputations over eleven years in a defined UK population- Benefits of multidisciplinary team working and prospective audit.

OBJECTIVE—To assess changes in diabetic lower-extremity amputation rates in a defined relatively static population over an 11-year period following the introduction of a multidisciplinary foot team. RESEARCH DESIGN AND METHODS—All diabetic patients with foot problems admitted to Ipswich Hospital, a large district general hospital, were identified by twice-weekly surveillance of all relevant in-patient areas and outcomes including amputations recorded. RESULTS—The incidence of major amputations fell 62%, from 7.4 to 2.8 per 100,000 of the general population. Total amputation rates also decreased (40.3%) but to a lesser extent due to a small increase in minor amputations. Expressed as incidence per 10,000 people with diabetes, total amputations fell 70%, from 53.2 to 16.0, and major amputations fell 82%, from 36.4 to 6.7. CONCLUSIONS—Significant reductions in total and major amputation rates occurred over the 11-year period following improvements in foot care services including multidisciplinary team work.

Altered C-Fiber Function as an Indicator of Early Peripheral Neuropathy in Individuals With Impaired Glucose Tolerance

OBJECTIVE This study explored the importance of glycemic burden compared with features of the metabolic syndrome in the pathogenesis of diabetic neuropathy by comparing C-fiber function in people with type 1 diabetes to that in people with impaired glucose tolerance (IGT). RESEARCH DESIGN AND METHODS The axon reflex–elicited flare areas (LDIflares) were measured with a laser Doppler imager (LDI) in age-, height-, and BMI-matched groups with IGT (n = 14) and type 1 diabetes (n = 16) and in healthy control subjects (n = 16). RESULTS The flare area was reduced in the IGT group compared with the control (2.78 ± 1.1 vs. 5.23 ± 1.7 cm2, P = 0.0001) and type 1 diabetic (5.16 ± 2.3 cm2, P = 0.002) groups, whereas the flare area was similar in the type 1 diabetic and control groups. CONCLUSIONS This technique suggests that small-fiber neuropathy is a feature of IGT. The absence of similar small-fiber neuropathy in those with longstanding type 1 diabetes suggests that glycemia may not be the major determinant of small-fiber neuropathy in IGT.

Abnormal LDIflare but normal quantitative sensory testing and dermal nerve fiber density in patients with painful diabetic neuropathy.

OBJECTIVE—Abnormal small nerve fiber function may be an early feature of diabetic neuropathy and may also underlie painful symptoms. Methods for assessing small-fiber damage include quantitative sensory testing (QST) and determining intraepidermal nerve fiber density. We recently described a reproducible physiological technique, the LDIflare, which assesses small-fiber function and thus may reflect early dysfunction before structural damage. The value of this technique in painful neuropathy was assessed by comparing it with QST and dermal nerve fiber density (NFD). RESEARCH DESIGN AND METHODS—Fifteen healthy control subjects, 10 subjects with type 2 diabetes and painful neuropathy (PFN), and 12 subjects with type 2 diabetes and painless neuropathy (PLN) were studied. LDIflare and QST were performed on the dorsum of the foot, and dermal NFD was determined. RESULTS—Results of both large- and small-fiber quantitative sensory tests were abnormal in patients with PLN but not those with PFN compared with control subjects. Dermal NFD was also significantly reduced in the PLN group compared with control subjects (205.8 ± 165.3 vs. 424.9 ± 176.3 [mean ± SD]; P = 0.003) but not in the PFN group (307.6 ± 164.5). In contrast, the LDIflare (square centimeters) was reduced in both PFN (1.59 ± 0.41) and PLN (1.51 ± 0.56) groups compared with control subjects (4.38 ± 1.4) (P < 0.001 for both). NFD correlated significantly with the LDIflare (r = 0.57, P < 0.0001). CONCLUSIONS—The LDIflare demonstrated impaired small-fiber function in patients with PFN when other assessments revealed no abnormality. We believe that this method has potential diagnostic value, particularly because it is noninvasive, has excellent reproducibility, and correlates with NFD. Furthermore, it may have an important role in assessing preventative therapies in early neuropathy.

Neurovascular Factors in Wound Healing in the Foot Skin of Type 2 Diabetic Subjects: Response to Catrina and Brismar

OBJECTIVE Delayed wound healing in diabetic patients without large-vessel disease has been attributed to microvascular dysfunction, neuropathy, and abnormal cellular and inflammatory responses. The role of these abnormalities has mainly been examined in animal models. Few studies have been undertaken in diabetic patients, and those that have are limited due to analysis in wounds from chronic ulcers. In this study, we quantified the rate of wound healing in relation to skin neurovascular function and structure following a dorsal foot skin biopsy in type 2 diabetes. RESEARCH DESIGN AND METHODS Twelve healthy control subjects and 12 type 2 diabetic subjects with neuropathy but without macrovascular disease were studied. We quantified rate of wound healing and related it to skin microvascular function (laser Doppler imager [LDI](max)), blood vessel density, small nerve fiber function (LDI(flare)) and nerve fiber density, vascular endothelial growth factor (VEGF) and its receptor (FLK1), and hypoxia-inducible factor (HIF)-1alpha expression. RESULTS The rate of wound closure was identical between control subjects and diabetic patients despite a significant reduction in maximum hyperemia (LDI(max)), epidermal and dermal VEGF-A, and epidermal and dermal blood vessel VEGFR-2 expression as well as the neurogenic flare response (LDI(flare)) and dermal nerve fiber density. There was no significant difference in HIF-1alpha and dermal blood vessel density between control subjects and diabetic patients. CONCLUSIONS In conclusion, the results of this study suggest that wound closure in subjects with type 2 diabetes is not delayed despite significant alterations in neurovascular function and structure.