Significance of antithyroid antibodies and other auto-antibodies in Saudi patients with chronic urticaria. Possible parameters in predicting chronic over three years disease

Prevalence, Clinical Manifestations, Treatment, and Clinical Course of Chronic Urticaria in Elderly: A Systematic Review

Purpose

Data specific to the epidemiology, clinical features, and management of chronic urticaria (CU) in the geriatric population remain limited and not well understood. We aim to systematically review the prevalence, clinical manifestations, treatment, and clinical course of elderly patients with CU.

Patients and methods

Original articles that included data of elderly (aged >60 years) with CU that were published until February 2021 were searched in PubMed, Scopus, and Embase using predfefined search terms. Related articles were evaluated according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses recommendations.

Results

Among the included 85 studies and 1,112,066 elderly CU patients, most (57.4%) were women. The prevalence of elderly CU in the general population ranged from 0.2–2.8%, and from 0.7–33.3% among all CU patients. Compared to adult CU, elderly CU patients had a higher percentage of wheal alone (73.9%), and lower rate of positive autologous serum skin test and atopy. Gastrointestinal diseases were the most common comorbidity (71.9%), and there was a high rate of malignancies and autoimmune diseases. Second generation H₁-antihistamines were commonly used, and achievement of complete control was most often reported. Omalizumab was prescribed in 59 refractory patients, and a significant response to treatment was reported in most patients. The treatment of comorbidities also yielded significant improvement in CU.

Conclusion

Elderly CU was found to be different from adult CU in both clinical and laboratory aspects. H₁- antihistamines are effective as first-line therapy with minimal side-effects at licensed doses. Treatment of secondary causes is important since the elderly usually have age-related comorbidities.

Chronic urticaria and thyroid autoimmunity: a meta-analysis of case-control studies

PURPOSE

Autoimmunity has been implicated in some patients with idiopathic chronic urticaria (CU). Because of the frequency of autoimmune thyroid diseases, their association with CU deserves special attention. We tested both the existence and the extent of an association between thyroid autoimmunity and CU.

METHODS

A thorough search of PubMed, Scopus, Web of Science, and Cochrane databases was performed. Studies reporting the positivity rate for anti-thyroperoxidase antibodies (TPOAbs) in people with (cases) and without CU (controls) were included. Quality of the studies was assessed by the Newcastle-Ottawa Scale. Between-study heterogeneity was assessed by Cochrane Q and I2 tests, and the odds ratio (OR) for TPOAbs positivity was combined using random-effects models.

RESULTS

Nineteen studies provided information about TPOAbs positivity on 14,351 patients with CU and 12,404 controls. The pooled estimate indicated a more than fivefold increased risk of exhibiting TPOAbs positivity in the group with CU (pooled OR 5.18, 95% CI 3.27, 8.22; P < 0.00001). Correction for publication bias had a negligible effect on the overall estimate (pooled adjusted OR: 4.42, 95% CI 2.84, 6.87, P < 0.0001). Between‑study heterogeneity was established (I2 = 62%, Pfor heterogeneity = 0.0002) and when, according to meta‑regression models, a sensitivity analysis was restricted to the 16 studies with the highest quality scores, the OR for TPOAbs positivity rose to 6.72 (95% CI 4.56, 9.89; P < 0.00001) with no significant heterogeneity (I2 = 31%, Pfor heterogeneity = 0.11).

CONCLUSIONS

Patients with CU have a five-to-nearly sevenfold higher risk of displaying TPOAbs positivity. All patients with CU may well be offered a screening for thyroid autoimmunity.

Autoimmune comorbidity in chronic spontaneous urticaria: A systematic review

BACKGROUND AND OBJECTIVE

Numerous autoimmune diseases (AIDs) have been linked to chronic spontaneous urticaria (CSU). Here, we provide the first extensive and comprehensive evaluation of the prevalence of AIDs in patients with CSU and vice versa.

METHODS

A Pubmed and Google Scholar search was performed to identify studies reporting the prevalence of various AIDs in CSU and vice versa published before April 2017.

RESULTS

The prevalence of individual AIDs in CSU is increased (≥1% in most studies vs ≤1% in the general population). AIDs with relatively high prevalence in the general population are also quite common in CSU patients, whereas those with low prevalence remain a rare finding in CSU. The rates of comorbidity in most studies were ≥1% for insulin-dependent diabetes mellitus, rheumatoid arthritis (RA), psoriasis and celiac disease (CD), ≥2% for Graves' disease, ≥3% for vitiligo, and ≥5% for pernicious anemia and Hashimoto's thyroiditis. Organ-specific AIDs are more prevalent in CSU than systemic (multiorgan or non organ-specific) AIDs. >2% of CSU patients have autoimmune polyglandular syndromes encompassing autoimmune thyroid disease (ATD) and vitiligo or pernicious anemia. Antithyroid and antinuclear antibodies are the most prevalent AID-associated autoantibodies in CSU. >15% of CSU patients have a positive family history for AIDs. The prevalence of urticarial rash in AID patients is >1% in most studies. This rash is more prevalent in eosinophilic granulomatosis with polyangiitis, ATD, systemic lupus erythematosus, RA and CD.

CONCLUSIONS

CSU patients have an increased risk of AIDs, especially adult female patients and those with a positive family history and a genetic predisposition for AIDs, who should be screened for signs and symptoms of AIDs.

Comorbidity of chronic spontaneous urticaria and autoimmune thyroid diseases: A systematic review

Patients with chronic spontaneous urticaria (CSU) are widely held to often have other autoimmune disorders, including autoimmune thyroid disease. Here, we systematically evaluated the literature on the prevalence of thyroid autoimmunity in CSU and vice versa. There is a strong link between CSU and elevated levels of IgG antithyroid autoantibodies (AAbs), with most of a large number of studies reporting rates of ≥10%. Levels of IgG against thyroid peroxidase (TPO) are more often elevated in CSU than those of other IgG antithyroid AAbs (strong evidence). Levels of IgG antithyroid AAbs are more often elevated in adult patients with CSU than in children (strong evidence). Patients with CSU exhibit significantly higher levels of IgG antithyroid AAbs (strong evidence) and IgE-anti-TPO (weak evidence) than controls. Elevated IgG antithyroid AAbs in CSU are linked to the use of glucocorticoids (weak evidence) but not to disease duration or severity/activity, gender, age, or ASST response (inconsistent evidence). Thyroid dysfunction rates are increased in patients with CSU (strong evidence). Hypothyroidism and Hashimoto's thyroiditis are more common than hyperthyroidism and Graves' disease (strong evidence). Thyroid dysfunction is more common in adult patients with CSU than in children (strong evidence) and in female than in male patients with CSU (weak evidence). Urticaria including CSU is more prevalent in patients with thyroid autoimmunity than in controls (weak evidence). CSU can improve in response to treatment with levothyroxine or other thyroid drugs (strong evidence). Pathogenic mechanisms in CSU patients with thyroid autoimmunity may include IgE against autoantigens, immune complexes, and complement.

The prevalence of thyroid autoimmunity in patients with urticaria: a systematic review and meta-analysis

Thyroid autoimmunity is the most common organ-specific autoimmune disorder, which is characterized by the production of thyroid autoantibodies and lymphocytic infiltration into the thyroid. The majority cases of chronic urticaria have unknown (idiopathic) causes, with about 30-40 % possibly having an autoimmune substrate. Considering that autoimmune factors may be the common features of both thyroid autoimmunity and urticaria, it is likely that both entities may coexist within the same patient. A number of studies have investigated the association between thyroid autoimmunity and urticaria. However, most of these studies are relatively small sample size, the power achieved in those studies was not sufficient to detect whether there is an association between urticaria and thyroid autoimmunity. The aim of this study is to combine primary data from all relevant studies to produce reliable estimates of the associations between thyroid autoantibodies and urticaria. Literature databases were searched including Medline, Embase, Web of Science, Chinese Wanfang, and CBM databases from January 1980 to December 2013. A total of 14,203 urticaria cases and 12,339 non-urticaria controls were included in this study. From these data, the odds ratio (OR) with 95% confidence interval (95% CI) was calculated. The meta-analysis results showed that the prevalence of positive thyroid autoantibodies in patients with urticaria was higher than non-urticaria controls (TgAb: OR 6.55, 95% CI 3.19-13.42, P<0.00001, I2=67%; TmAb: OR 4.51, 95% CI 2.78-7.33, P<0.00001, I2=47%; TPOAb: OR 8.71, 95% CI 6.89-11.01, P<0.00001, I2=20%, respectively). The results of this meta-analysis suggested that patients with urticaria were more likely to have thyroid autoimmunity than the control groups.