The characteristics and impact of pruritus in adult dermatology patients: A prospective, cross-sectional study.

BACKGROUND: Pruritus often accompanies chronic skin diseases, exerting considerable burden on many areas of patient functioning; this burden and the features of pruritus remain insufficiently characterized. OBJECTIVE: To investigate characteristics, including localization patterns, and burden of pruritus in patients with chronic dermatoses. METHODS: We recruited 800 patients with active chronic skin diseases. We assessed pruritus intensity, localization, and further characteristics. We used validated questionnaires to assess quality of life, work productivity and activity impairment, anxiety, depression, and sleep quality. RESULTS: Nine out of every 10 patients had experienced pruritus throughout their disease and 73% in the last 7 days. Pruritus often affected the entire body and was not restricted to skin lesions. Patients with moderate to severe pruritus reported significantly more impairment to their sleep quality and work productivity, and they were more depressed and anxious than control individuals and patients with mild or no pruritus. Suicidal ideations were highly prevalent in patients with chronic pruritus (18.5%) and atopic dermatitis (11.8%). CONCLUSIONS: Pruritus prevalence and intensity are very high across all dermatoses studied; intensity is linked to impairment in many areas of daily functioning. Effective treatment strategies are urgently required to treat pruritus and the underlying skin disease.

Acetylcholine-induced whealing in cholinergic urticaria - What does it tell us?

BACKGROUND: Cholinergic urticaria (CholU) is characterized by the occurrence of itchy wheals induced by sweating. Intradermal injections of acetylcholine (ACh) have been proposed to help with diagnosing CholU and subgrouping of patients, but controlled studies are largely missing. OBJECTIVE: To compare the rates of positive ACh test results in well characterized CholU patients and controls and to identify clinical features of CholU linked to ACh reactivity. METHODS: Acetylcholine was injected intradermally into 38 CholU patients and 73 matched healthy controls. Wheal and flare skin responses were assessed after 15 and 30 min and correlated with clinical features of CholU. RESULTS: At 15 min after intradermal injections of ACh, wheal and flare responses were significantly more frequent in CholU patients than healthy controls, wheals: 34 % vs.15% (P = 0.028); flares: 50 % vs.18 % (P <0.001). Also, wheals were 37 % and flares 172 % larger and of longer duration in CholU patients than in healthy controls (both P < 0.01). CholU patients with ACh-induced wheals (ACh+) had larger flare but not wheal responses in response to histamine than those without (ACh-; P = 0.011). Also, ACh-induced wheal responses were significantly correlated with sweating (r = 0.54, P = 0.046) in CholU patients. Finally, wheal responses lasted longer in ACh+ than in ACh- patients (P = 0.03). CONCLUSION: Intradermal ACh testing does not allow for the identification of CholU patients due to its low sensitivity. ACh-induced wheals, in patients with CholU, is linked to sweating and longer lasting symptoms. Intradermal ACh testing is an interesting tool for mechanistic studies in CholU.

Sensitization against skin resident fungi is associated with atopy in cholinergic urticaria patients.

BACKGROUND: Cholinergic urticaria (CholU) is a common type of chronic inducible urticaria, characterized by small itchy wheals that appear upon physical exercise or passive warming. Malassezia globosa, a skin resident fungus, has been identified as an antigen that induces mast cell/basophil degranulation and wheal formation through specific IgE, in Japanese patients with atopic dermatitis and CholU. In this study we aimed in assessing the rate of IgE sensitizations against skin resident fungi in European CholU patients. METHODS: We assessed serum IgE levels to Malassezia furfur, Candida albicans and Trichophyton mentagrophytes using routine lab testing and Malassezia globosa using a newly established ELISA. We correlated the results to wheal formation and other clinical features. RESULTS: Four patients (of 30 tested) had elevated levels of IgE against Malassezia furfur and Candida albicans and two had elevated levels of IgE against Trichophyton mentagrophytes. Four sera (of 25 tested) had elevated levels of IgE to the Malassezia globosa antigen supMGL_1304. Sensitization to one skin fungus was highly correlated with sensitization to the other tested fungi. We saw highly significant correlations of sensitization to supMGL_1304 with wheal size in the autologous sweat skin test (rs = 0.7, P = 0.002, n = 19), the Erlangen atopy score (rs = 0.5, P = 0.03, n = 19), total IgE serum levels (rs = 0.5, P = 0.04, n = 19) and a positive screen for IgE against common airborne/inhalant allergens s (sx1; rs = 0.54, P = 0.02, n = 19). CONCLUSIONS: Sensitization to skin resident fungi including Malassezia globosa is uncommon in European CholU patients, but is associated with atopy and pronounced wheal formation upon dermal contact with their own sweat.Trial registration German Clinical Trials Registry DRKS-ID: DRKS00004277.