Validation of the 5-D Itch Scale in Three Ethnic Groups and Exploring Optimal Cutoff Values Using the Itch Numerical Rating Scale

Background. Chronic pruritus is a common and distressing condition that has serious emotional and psychosocial consequences. Due to its subjective nature, self-report questionnaires are widely implemented as cost-effective measures to gauge the severity of chronic pruritus. The current study is aimed at validating the 5-D itch scale in three ethnic groups—Black, Asian, and Hispanic—with the well-validated Itch Numerical Rating Scale (NRS) and Worst Itch NRS (WI-NRS) and developing its cutoff value using receiver operating characteristics (ROC) and inspection of the area under the curve (AUC) across ethnic groups. At the same time, it is aimed at comparing the concurrent prevalence of itch and depression in these populations, who often form ethnic minorities in many countries. The current study addresses the knowledge gap of cultural adaptation of the 5-D pruritus scale for greater usage. Methods. Community samples of three ethnic groups were recruited from an online platform of Qualtrics and administered the self-report questionnaires of Itch-NRS, 5-D itch scale, and Patient Health Questionnaire-9 (PHQ-9) to measure their pruritus domains, itch intensity, depression screening, and its severity. Informed consent was obtained from all participants. Subgroup analysis was conducted, including concurrent validity and cutoff values compared between each ethnic group. Concurrent prevalence of itch and depression was evaluated using the cutoff value of Itch-NRS and PHQ-9. Result. A total of 2323 participants were included in the study. A significant positive correlation ( p < 0.001 ) was found between the Itch-NRS, WI-NRS, and 5-D itch scale. The cutoff value of the 5-D itch scale was established for the three ethnic groups using ROC, with a cutoff value of Itch-NRS as a reference. Conclusions. The 5-D itch scale has demonstrated sound psychometric properties in three ethnic groups and is closely related to Itch-NRS. The analysis of the cutoff value of the 5-D itch scale suggests that different cutoff values should be considered to reduce the inflation of pruritus severity.

Prurigo nodularis, prurigo chronica, new therapeutic options

Prurigo nodularis (PN) is a skin disease that develops on chronically itchy skin. There are various causes behind the chronic itch. Due to intensive research in recent years different mechanisms that can participate in the development of chronic pruritus have been discovered, opening up new therapeutic targets for treatment. Here we review the various mechanisms behind chronic pruritus and discuss the novel therapies for PN.

What Do We Know about Pruritus in Very Young Infants? A Literature Review

In infants, pruritus is frequently considered as absent because they do not scratch themselves. Because pruritus could induce severe adverse effects in this vulnerable population, we aimed to review existing evidence on the ability of young infants to experience itch and on how to assess itch-related discomfort in this population. A literature review was performed (Pubmed, Google Scholar). Neurological itch pathways are well described. Skin development starts early during gestation. At 34 weeks of gestation, skin is almost complete while skin adaptations occur after birth. Newborn skin is neurologically functional, including the ability for young infants to feel pain. Similarities and interactions between pain and pruritus support the hypothesis that infants could feel pruritus. However, the existence of pruritus in infants has never been evidenced. Many itchy conditions can affect them, suggesting non-negligible prevalence of infant pruritus among which atopic dermatitis (AD) is the most studied disease. Studies reported a negative impact of AD on children and their families. There is no existing validated method to assess pruritus in infants, although they may feel pruritus and chronic pruritus can lead to serious adverse effects. To appropriately diagnose pruritus appears of great interest among young infants. Development of a method is required to this aim.

Cannabinoids for the treatment of refractory neuropathic pruritus in amyotrophic lateral sclerosis: A case report

Background: Neuropathic symptoms have a wide variety of manifestations, ranging from pain to pruritus. Neuropathic pruritus is a type of chronic pruritus related to damaged small fibers. Cannabinoids have evidence to manage neuropathic symptoms. We present a case of refractory neuropathic pruritus that was successfully managed with the use of oral cannabinoids. Case presentation: A 60-year-old male with amyotrophic lateral sclerosis with ongoing pruritus despite the use of standard neuropathic therapies. Possible course of action: Sodium channel and N-methyl-D-aspartate receptor antagonists have evidence for neuropathic symptoms but can cause significant gastrointestinal side effects. Prescription cannabinoids such as nabiximol can be cost prohibitive to use in practice. Synthetic tetrahydrocannabinol products are dose limited by psychoactive side effects. Formulation of a plan: A balanced oral cannabinoid from a licensed producer was preferred as it has evidence for neuropathic symptoms and is generally well tolerated. Outcome: The patient showed improvement to his pruritus score from 7/10 to 3/10. There was initial increased sedation but tolerance developed quickly. Lessons learned from case: Cannabinoids are possibly safe and effective in management of neuropathic pruritus. View on research problems: Additional research is needed to establish efficacy and safety.