Diabetic neuropathy

Body Mass Index and Parotidectomy Outcomes

Multiple specialties have demonstrated increased risk of certain postoperative complications in patients with an increased body mass index (BMI). The goal of this study was to understand the outcomes of patients undergoing parotidectomy with an increased BMI and to identify any other patient risk factors for postoperative complications. This study was a retrospective chart review of 432 patients. Patient variables collected included BMI, age, gender, history of diabetes mellitus, type of parotidectomy, and pathology. Outcomes reviewed included facial nerve weakness, hematoma or seroma formation, and wound infection. The results showed that BMI had no statistically significant effect on complications. However, patients undergoing a total parotidectomy, malignant pathology, and patients with a history of diabetes mellitus had significantly more postoperative facial weakness. In conclusion, BMI does not influence postoperative complications in patients undergoing parotidectomy. Patients with diabetes, those undergoing total parotidectomies, and patients with malignant pathology have significantly more facial weakness and should be counseled accordingly.

The efficacy of Jing Wan Hong ointment for nerve injury diabetic foot ulcer and its mechanisms

Jing Wan Hong ointment contains 30 kinds of Chinese herbs, with functions of activating blood circulation to disperse blood stasis, clearing heat, eliminating dampness, and reducing swelling by detoxification. Therefore, Jing Wan Hong ointment may facilitate the healing of ulcers. The aim of this study was to evaluate the efficacy and mechanisms of Jing Wan Hong ointment for healing diabetic foot ulceration in Wistar rats induced by streptozotocin and sciatic nerve damage. The results showed that Jing Wan Hong ointment had a marked effect on foot ulcers in diabetic rats induced by initial nerve injury. These effects were manifested by reducing the foot ulcer size and Wagner grade after seven days of treatment. The diabetic rats with foot ulcers were almost healed after 21 days of treatment. Moreover, the mechanisms of this effect seem to be dependent on increased expression of PDGF mRNA, but there was no influence on the expression of TGF-β, VEGF, and FLT-1 mRNA.

Retinoic acid increases tissue and plasma contents of nerve growth factor and prevents neuropathy in diabetic mice

BACKGROUND

Decreased production of nerve growth factor (NGF) may contribute to diabetic neuropathy; however, exogenous administration of NGF induces only a modest benefit. Retinoic acid (RA) promotes the endogenous expression of nerve growth factor and its receptor. We studied the effects of RA on diabetic neuropathy in mice with streptozotocin-induced diabetes.

MATERIAL AND METHODS

One hundred and twenty National Institutes of Health (NIH) albino mice randomly separated into three groups (A, n = 30; B, n = 30; C, n = 60). Diabetes mellitus was induced with streptozotocin in groups A and B. Animals from group A received a subcutaneous injection of 25 microl of mineral oil daily for 90 days, while those from group B received a subcutaneous injection of 20 mg kg(-1) of all trans RA. Animals from group C were taken as controls. At the end of the experiment, blood glucose and NGF levels (both in serum and sciatic nerve) were measured. Two behavioural tests were conducted in a blind fashion to detect abnormalities of thermal and nociceptive thresholds.

RESULTS

Contents of NGF in healthy untreated mice were 1490 +/- 190 pg mg(-1) in nerve and 113 +/- 67 pg mg(-1) in serum; in diabetic untreated mice the values were 697 +/- 219 pg mL(-1) in nerve and 55 +/- 41 pg mL(-1) in serum; and in diabetic mice treated with RA the values were 2432 +/- 80 pg mL(-1) in nerve and 235 +/- 133 pg mg(-1) in serum (P < 0.002). Ultrastructural evidence of nerve regeneration and sensitivity tests improved in diabetic mice treated with RA as compared with nontreated diabetic mice.

CONCLUSION

Our findings indicate that administration of RA increases serum and nerve contents of NGF in diabetic mice and suggest a potential therapeutic role for retinoic acid in diabetic patients.

Acquired peripheral neuropathy

The element of time is a crucial factor in the electrodiagnostic presentation of PN. The characteristic changes seen in various neuropathies evolve over time. If testing is performed very early in the course of the disease, abnormalities may not yet be present, in part, because the range of normal values for NCS parameters is broad. In addition, if the process is asymmetric, the affected nerves may not be sampled. Very late in the course of the disease, a multifocal process may appear diffuse and symmetric as the areas of focal involvement coalesce. A primarily, demyelinating process may begin to demonstrate secondary axonal involvement. In very severe neuropathies, it may become difficult to evoke any NCS responses to characterize the neuropathy. It is essential to place the electrodiagnostic findings within the context of the clinical progression to avoid drawing erroneous conclusions. Sometimes, the true nature of the neuropathy is clear only after sequential testing. The etiologic diagnoses of acquired polyneuropathy are vast. A well-crafted electrodiagnostic evaluation can categorize neuropathies into more specific diagnostic groups by identifying the descriptive diagnosis, significantly narrowing the list of possible etiologic diagnoses. Electrodiagnostic testing, which always starts with a pertinent history and physical examination, should always be viewed as a continuation and quantification of the physical examination. Only by knowing the extent and pattern of the clinical involvement is it possible to formulate a thorough electrodiagnostic evaluation. This knowledge is especially important in cases in which the presentation is multifocal, because the neuropathy can be missed entirely if the affected nerves are not evaluated. When evaluating a neuropathy, there are three important questions to answer: (1) Is the process diffuse or multifocal? (2) Is it demyelinating or axonal? (3) Does it predominantly involve the motor or sensory nerves? By assessing the neuropathy along these three axes, the large number of possible etiologic diagnoses becomes much more manageable.