BACKGROUND: Streptococcal tonsillitis has been implicated in psoriasis; however, few population studies have examined its role in the pediatric population.

OBJECTIVE: To investigate the association between tonsillitis and pediatric psoriasis METHODS: Data from the Danish National Birth Cohort were obtained on parentally reported psoriasis by age 11 years and history of tonsillitis at ages 6 - 18 months, 10 - 11 years, and (from hospital patient registry data) 0 - 11 years. We estimated odds ratios (ORs) and 95 % Confidence Intervals (CIs) of pediatric psoriasis using logistic regression analyses.

RESULTS: In total, 35 188 offspring were eligible for analyses. Tonsillitis at 6 - 18 months was not associated with pediatric psoriasis (adjusted OR 0.73, 95 % CIs 0.47-1.14), nor was recent tonsillitis at ages 10 - 11 years (adjusted OR 1.09, 95 % CI 0.81-1.47). However, recurrent tonsillitis between ages 10 - 11 was strongly associated with pediatric psoriasis (adjusted OR 2.28, 95 % CIs 1.17-4.48). Our results for streptococcal tonsillitis indicated a potential association (adjusted OR 2.12, 95 % CIs 0.86, 5.17).

LIMITATIONS: It was not possible to clarify the temporal relationship between tonsillitis and pediatric psoriasis CONCLUSION: Recurrent tonsillitis is of clinical relevance to pediatric psoriasis.