Chronic Pruritis Research Articles

Treating Chronic Pruritus: Are We at the Threshold of a Breakthrough?

Chronic pruritis, characterized by persistent itchiness lasting more than six weeks, affects up to 15% of the population, significantly impairing quality of life. Despite its prevalence and impact, there is an absence of FDA-approved medications specifically for the treatment of chronic pruritus, highlighting a significant unmet need in dermatology. Advancements in dermatologic medications, however, including the development of biologics and Janus kinase (JAK) inhibitors, signal potential breakthroughs in pruritus management through a radically different mechanism of action that focuses on their effect on the nervous system. Currently, the most commonly utilized treatments for pruritis are sedating antihistamines, which have been largely ineffective for non-histamine-induced itch, underscoring the necessity for novel approaches. This editorial reviews key studies and clinical trials with a particular focus on cases of prurigo nodularis, where itch serves as the primary pathology rather than just a symptom. The effectiveness of dupilumab in phase III trials for treating prurigo nodularis, independent of its effects on dermatitis or atopic background, alongside the success of JAK inhibitors in managing chronic idiopathic pruritus, indicates a shift towards therapies that directly and specifically target itch nerve pathways instead of indirectly via immune system modulation or sedation. These developments suggest that significant progress may be on the horizon for treating chronic itch, providing hope for those suffering from pruritis, the number one cause of misery in dermatology.

A novel anti-pruritic: Topical co-administration of high molecular weight hyaluronan (HMWH) with protamine, a transdermal transport enhancer.

Pruritis, the sensation of itch, is produced by multiple substances, exogenous and endogenous, that sensitizes specialized sensory neurons (pruriceptors and pruri-nociceptors). Unfortunately, many patients with acute and chronic pruritis obtain only partial relief when treated with currently available treatment modalities. We recently demonstrated that the topical application of high molecular weight hyaluronan (HMWH), when combined with vehicles containing transdermal transport enhancers, produce potent long-lasting reversal of nociceptor sensitization associated with inflammatory and neuropathic pain. In the present experiments we tested the hypothesis that the topical formulation of HMWH with protamine, a transdermal transport enhancer, can also attenuate pruritis. We report that this topical formulation of HMWH markedly attenuates scratching behavior at the nape of the neck induced by serotonin (5-hydroxytryptamine, 5-HT), in male and female rats. Our results support the hypothesis that topical HMWH in a transdermal transport enhancer vehicle is a strong anti-pruritic.

Mycosis Fungoides

Mycosis fungoides, also known as cutaneous T-Cell lymphoma, is a rare hematologic malignancy characterized by cutaneous involvement. There is significant variability in dermatologic presentation in early stages and often atypical pathology findings on biopsy that often make early diagnosis quite challenging. Here we present a case of an elderly patient who presented with chronic pruritis and cutaneous T-Cell Lymphoma involving the entire body, currently managed with a combination of phototherapy and anti-pruritic topical medications.

A monocentric, single-group study to evaluate the effect of pramoxine containing moisturizing cream in participants with pruritis

Objectives: The objective of the study was to evaluate the effectiveness of a blend of moisturising cream with anesthetic agent for the treatment of pruiritis. Materials and Methods: A prospective, single-group, and single-center trial to assess the efficacy and acceptability of moisturizing cream in patients with pruritis was carried out. The study included patients who were diagnosed at least once at one site with chronic pruritis with dryness, chronic itch for more than 6 weeks (H/o Itch every day), and itch score on visual analogue scale (VAS) (mild-to-moderate – equal to or <7 on VAS). P = 0.05 or lower indicated statistical significance. Results: A total of 32 patients were included in the study. Following the application of moisturizing cream, the percentage reduction in pruritis severity ranged from 26.3% at 3 min to 66.9% at 8 h. The mean itch score at baseline was 5.922 ± 0.908, while at 3 min, it was 4.366 ± 2.034. At 8-h post-application, it was 2.781 ± 1.460. The P-value for all the itch scores after application of the moisturizing cream right from 3-min to 8-h post-application was 0.001 which is highly significant. Conclusion: In patients with chronic pruritis, moisturizing cream with pramoxine as the topical local anesthetic significantly decreased the mean itch score. The onset of action began as soon as 3 min after application, and over the course of 8 h, a noticeable decrease in the severity of pruritis was seen in this study. The cream was well tolerated with no adverse effects in this study.

Novel aspects of the current guideline for chronic pruritus

Chronic pruritus is still a major challenge for patients and treating doctors, as chronic pruritis mostly constitutes a difficult to treat symptom of different diseases. In this article we summarize the most recent changes of the current German guidelines on chronic pruritus and give practical recommendations for the diagnosis and therapy.

Assessment and classification of chronic pruritis and its relation to systemic diseases

Although pruritis might not be a serious condition with significant healthcare impacts, it is usually associated with an unpleasant sensation that leads to scratching the skin. It has been demonstrated that the severity of the condition is significantly variable and ranges between disabling and mild conditions. Chronic pruritis has been defined as the presence of daily itching for >6 months. In the present literature review, we have discussed the different approaches that have been previously indicated to assess and evaluate chronic pruritis, and the classification of the condition its relation to the different systemic diseases. The classification of chronic pruritis can be done using a clinical or an etiological diagnosis. The clinical diagnosis is usually based a primary skin condition, while the etiological diagnosis is based on the presence of different diseases that may be systematic, neurological, or psychiatric disorders. Accordingly, conducting a thorough examination is essential to establish a proper diagnosis before adequately managing the affected patients. Furthermore, the treatment of the underlying etiology should also be adequately considered for adequate management and enhanced prognosis.

Cell type-specific modulation of sensory and affective components of itch in the periaqueductal gray

Itch is a distinct aversive sensation that elicits a strong urge to scratch. Despite recent advances in our understanding of the peripheral basis of itch, we know very little regarding how central neural circuits modulate acute and chronic itch processing. Here we establish the causal contributions of defined periaqueductal gray (PAG) neuronal populations in itch modulation in mice. Chemogenetic manipulations demonstrate bidirectional modulation of scratching by neurons in the PAG. Fiber photometry studies show that activity of GABAergic and glutamatergic neurons in the PAG is modulated in an opposing manner during chloroquine-evoked scratching. Furthermore, activation of PAG GABAergic neurons or inhibition of glutamatergic neurons resulted in attenuation of scratching in both acute and chronic pruritis. Surprisingly, PAG GABAergic neurons, but not glutamatergic neurons, may encode the aversive component of itch. Thus, the PAG represents a neuromodulatory hub that regulates both the sensory and affective aspects of acute and chronic itch.

P484 Cobalt as the culprit: vitamin B12 supplementation as a trigger for chronic pruritis

P484 Cobalt as the culprit: vitamin B12 supplementation as a trigger for chronic pruritis

Hodgkin's Disease Presenting with Chronic Pruritis and Cutaneous Involvement.

Hodgkin's Disease Presenting with Chronic Pruritis and Cutaneous Involvement.

Gabapentin for the Treatment of Neurogenic Pruritis

Peripheral neurogenic pruritis is defined as localized itching in the absence of a rash and other known systemic or central nervous system diseases that cause pruritis. Effective treatment of this non-histamine-mediated pruritis is challenging. Here we present a case of neurogenic pruritis that responded to Gabapentin. Gabapentin 300-1200 mg daily was used to treat a patient with peripheral neurogenic pruritis. A 38 year-old white male was referred to the allergy/immunology clinic at Virginia Commonwealth University for chronic pruritis without rash not relieved by antihistamine therapy. A prior dermatology work-up included negative ANA, anti-thyroglobulin and anti-TPO titers, normal skin biopsy, normal ESR and normal CT exams of the chest, abdomen and pelvis. Prick skin testing was positive for environmental allergens. Patient was started on immunotherapy for environmental allergies; and on cyclosporine-A (150 mg daily) with only modest relief of pruritis. Permethrin and Ivermectin for presumed scabies also provided no relief. A short course of systemic steroids minimally reduced symptoms. In the allergy clinic, prior medications for pruritis were discontinued. Gabapentin was initiated at 300 mg daily, and increased to 900 mg daily. This dose was well tolerated and pruritis substantially improved. In a follow up visit 1 month later, patient's dose was escalated to 1200 mg PO daily which was well tolerated, resulting in only minimal residual pruritis. We believe this is the first reported case of spontaneous peripheral neurogenic pruritis that responded to Gabapentin. Further studies of Gabapentin for this condition as well as other forms of pruritis are warranted.