CHRONIC spontaneous urticaria (CSU) in systemic lupus erythematosus (SLE) was not linked to higher disease activity, but was associated with distinct clinical and laboratory risk factors.
Systemic Lupus Erythematosus with Chronic Spontaneous Urticaria
A multicenter retrospective study evaluated epidemiologic features of SLE comorbid with CSU, the relationship between CSU onset and
lupus disease activity, and potential risk factors for this comorbidity
pattern. Investigators analyzed 40 patients with SLE and CSU alongside
160 age matched and sex matched SLE controls without CSU.
To assess whether CSU tracked with lupus activity, the authors compared Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) scores
before and after CSU onset within the SLE-CSU cohort using a Wilcoxon
signed rank test. They also compared disease activity at SLE onset
between groups using the Mann-Whitney U test, and evaluated differences
in activity grading, manifestations, laboratory findings, and treatments
using χ2 testing. Univariate and multivariate logistic regression were
used to identify independent predictors of CSU occurrence in SLE.
Chronic Spontaneous Urticaria Did Not Signal Higher Lupus Activity
Within the SLE-CSU group, CSU occurrence did not correspond to an
increase in SLEDAI scores, suggesting that CSU was not a reliable marker
of heightened systemic lupus erythematosus activity in this cohort. The
authors emphasize that clinicians should avoid assuming flare level
disease based on CSU alone, and instead interpret urticaria in the broader context of clinical findings and laboratory data.
Risk Factors Linked to SLE With CSU
In univariate comparisons, several variables differed between
systemic lupus erythematosus patients with CSU and those without CSU,
including cylindruria, elevated IgM, elevated IgA, elevated IgG,
serositis, mucosal ulcers, and anti-Pm-Scl antibodies. In multivariate
analysis, four factors remained independently associated with CSU
occurrence in systemic lupus erythematosus: cylindruria (OR 6.152),
elevated IgA (OR 7.598), elevated IgG (OR 3.252), and mucosal ulcers (OR
3.838).
The findings suggest that SLE with CSU may reflect specific
comorbidity patterns and immune laboratory profiles rather than higher
global disease activity. In practice, systemic lupus erythematosus
patients presenting with CSU may warrant targeted evaluation for these
associated features, particularly urinary findings, immunoglobulin
elevations, and mucosal involvement.
