Multifactorial causes of chronic itch in diabetes: More than just neuropathy

BACKGROUND

Chronic pruritus is common in patients with diabetes though its pathophysiology is unknown and difficult to pinpoint given the multi-system manifestations of diabetes. Herein, we aim to evaluate the severity of chronic itch in patients with diabetes and its association with glycaemic control, microvascular complications and quality of life.

METHODS

We conducted a retrospective study of 105 adults with diabetes evaluated by a dermatologist at a tertiary care centre in Mexico City. Degree of chronic pruritus and its impact on quality of life as well as laboratory, clinical and demographic data were collected. Patients without chronic pruritus (n = 62) were compared to those with chronic pruritus (n = 43). The latter cohort was further stratified by itch severity, and characteristics of their itch were quantified.

RESULTS

Neuropathy and loss of protective sensation were more common in patients with chronic pruritus, compared to those without chronic pruritus (p = 0.007 and p = 0.001, respectively). Anxiety and depression were more common in individuals with chronic pruritus (p = 0.009), and these group reported higher effect of pruritus on their quality of life (p < 0.0001). The most common sites of itch were the head, back and arms. Among patients with chronic itch, increasing itch severity was associated with decreasing eGFR (p = 0.080).

CONCLUSIONS

The underlying cause of chronic itch in patients with diabetes is likely multifactorial and owing to microvascular complications such as neuropathy and nephropathy. Better understanding of the causes of itch in these patients can allow for more targeted treatment, leading to improved quality of life.

[Eczema herpeticum in a patient with atopic dermatitis, carrying r501x and 2282del4 filaggrin null mutations]

Eczema herpeticum is an acute dermatoses caused by herpes simplex virus type 1 in atopic dermatitis patients, and is considered a dermatology emergency. Eczema herpeticum occurs in less than 3% of atopic patients. We report a patient with a history of atopic dermatitis who presented to an emergency department with eczema herpeticum. He was admitted and treated with antiviral medications with good outcome. We investigated filaggrin null mutations in the patient and his family and correlate them with the severity of the disease. We present the first Mexican patient with eczema herpeticum, atopic dermatitis and the presence of R501 X and 2282del4 filaggrin null mutations.

α-Synuclein inclusions in the skin of Parkinson's disease and parkinsonism

Objective

The presence in the brain of α-synuclein containing Lewy neurites, or bodies, is the histological hallmark of Parkinson's disease (PD). The discovery of α-synuclein aggregates in nerve endings of the heart, digestive tract, and skin has lent support to the concept of PD as a systemic disease. Our goals were, first, to demonstrate the presence of α-synuclein inclusions in the skin and, second, to detect quantitative differences between patients with PD and atypical parkinsonism (AP).

Methods

Skin biopsies were taken from 67 patients and 20 controls. The biopsies underwent immunohistochemistry (IHC) and immunofluorescence (IF) testing for α-synuclein, whereupon its presence was quantified as the percentage of positive cells. Patients were divided into those with PD and those with AP. AP patients included AP with neurodegenerative disease (proteinopathies) and secondary AP.

Results

Sixty-seven patients (34 with PD) and 20 controls were recruited. In the PD group, α-synuclein was detected in 58% of the cells in the spinous cell layer (SCL), 62% in the pilosebaceous unit (PSU), and 58% in the eccrine glands (EG). The AP-proteinopathies group showed 7%, 7%, and 0% expression of α-synuclein, respectively. No expression was found in the skin of the control group.

Conclusions

The expression of α-synuclein in the skin was relatively high in the PD group, scarce in AP, and null for the individuals in the control group. While these findings require further confirmation, this minimally invasive technique may aid in the improvement of the accuracy of PD diagnoses.

[The skin and the endocrine system]

The skin is an organ closely related to the endocrine system. The endocrine system has an important role in the skin development and its normal physiology. Skin, pilosebaceous unit, eccrine, and apocrine sweat glands have hormonal receptors and are targets of hormones. On the other hand, the skin synthesizes a variety of hormones and thus it may be considered as an endocrine organ. This article is an overview of the effects of some hormones on the skin.