Characterizing Pruritus in Autoimmune Connective Tissue Diseases

October 2019 | Volume 18 | Issue 10 | Original Article | 995 | Copyright © October 2019

Yahya Argobi MD FAAD,a,b Gideon P. Smith MD MPH PhDb

aKing Khalid University, Abha, Saudi Arabia

bDepartment of Dermatology, Massachusetts General Hospital, Boston, MA 

Abstract
Background: Autoimmune connective tissue diseases (ACTDs) are a broad range of diseases featured by immune dysregulation, and often have multisystem involvement with prominent skin manifestations. Pruritus is one of the most common symptoms in these diseases, with significant impact on the quality of life of patients.

Objective: To characterize the frequency, location, severity, and timing relative to disease onset of pruritus in different ACTDs.

Methods: A chart review of all patients seen in the Rheumatology-Dermatology clinic at Massachusetts General Hospital. Results: Itch was a troubling symptom in 83% of dermatomyositis (DM), 61% of systemic lupus erythematosus (SLE), 59% of Sjogren syndrome (SJO), 22% of systemic sclerosis (SSc), and 60% of mixed connective tissue disease. In DM and SLE, itch paralleled the course of inflammatory skin manifestations in 83% and 45%, respectively. Itch in DM is more intense and more treatment resistant in 12% vs 1% in SLE. In contrast, itch in SSc and SJO tended to occur later in the disease course, 86% vs 42%, respectively.

Conclusion: Itch is common in all ACTDs and often under-evaluated and under treated. Pruritus is more common and more severe in DM than in SLE. Treatment of pruritus in ACTDs can be challenging, and sometimes multi-modal therapy is warranted.

J Drugs Dermatol. 2019;18(10):995-998.

INTRODUCTION

Autoimmune connective tissue diseases (ACTDs) are a broad range of diseases, the most common being systemic lupus erythematosus (SLE), dermatomyositis (DM), systemic sclerosis (SSc), Sjogren syndrome (SJO), and mixed connective tissue disease (MCTD), featured by immune dysregulation and often have multisystem involvement. Although these diseases are commonly primarily managed by rheumatologists, they often have prominent skin manifestations. Pruritus is one of the most common skin-symptoms in ACTDs and can be severe with significant impact on the quality of life of patients.1-2 A prospective study conducted to compare clinical characteristics of DM between 2 tertiary medical centers in the United States and Singapore showed that itch was the most common initial symptom among both populations, representing 63% and 80% of patients in the United States and Singapore, respectively.3 However, little is known about the absolute and relative differences in pruritus between ACTDs. Pruritus itself is just a symptom and understanding the pattern of pruritus in each disease may help us identify different etiologies and therefore give different treatment targets to alleviate the symptom.

METHODS

This study was designed to characterize the frequency, location, severity, and timing relative to disease onset of pruritus in different autoimmune connective tissue diseases (ACTDs), to identify if these characteristics can be related to potentially different etiologies of itch and suggest the most appropriate intervention for pruritus in the different conditions, and to examine the frequency with which pruritus is evaluated and treated in ACTDs in standard vs specialty sub-clinic care.

We performed a retrospective chart review of all patients seen at the Rheumatology-Dermatology (Rheum-Derm) clinic at Massachusetts General Hospital, Boston, MA between November 2012 and December 2017. The study was reviewed and approved by Partners IRB (protocol # 2014P001562). Chart review was by the first author. Location of itch was extracted from patient HPI and therapy from the assessment and plan. Patients included in the study were those with a confirmed diagnosis of DM, SLE, SJO, SSc or MCTD by independent board-certified rheumatologists in consultation with board-certified dermatologist specifically trained in this area. Patients with a different diagnosis, such as systemic vasculitis, sarcoid, psoriasis, etc., were not included in our analysis. We also reviewed the evaluation and treatment for itch for this patient set in the visit-documentation of rheumatology, dermatology, or referring physicians, preceding their visit in rheum-derm.

RESULTS

Of 1486 visits and 734 patients, 197 patients fit our criteria. The mean age was 51 years (range, 16–94), and 80% of the sample was female. Of the 197 patients with ACTDs, 57% complained of pruritus during our initial clinic visit (Table 1). Rheumatologists documented pruritus in only 1% of the patients they referred whereas dermatologists documented pruritus in 94% of patients they referred. Itch differed in frequency, location, timing