Clinical and epidemiological features of pityriasis lichenoides in children

Introduction. According to current concepts, lichenoid pityriasis (LP) is classified as a parapsoriasis with a benign course. The disease is diagnosed in childhood and adolescence, most often in males. Studying the structure and prevalence of LP, as well as risk factors influencing the onset and progression of the acute and chronic forms of the disease in children, is highly relevant.
Objective. To analyze the clinical and epidemiological characteristics and risk factors influencing the onset of LP in children.
Materials and methods. A single-center prospective observational study was conducted. The study included data from 130 children undergoing outpatient treatment and observation at the Moscow Scientific and Practical Center of Dermatovenereology and Cosmetology from January 2022 to March 2025. Statistical analysis methods were used: the χ² test and calculation of odds ratios (OR) with a 95 % confidence interval (CI).
Results. A consistent upward trend in the incidence of LP has been observed in the Moscow pediatric population in recent years. No statistically significant differences in the incidence of acute LP depending on gender and age were found. Males in the 7–14-year age group were more susceptible to developing LP (63.8%). A high diagnostic error rate (33.1%) was observed. Statistically significant risk factors were identified: climate change for acute LP (OR = 66.25), and seasonality for chronic LP (OR = 81.14). Herpes infections were diagnosed 1.6 times more often in patients with acute LP than in those with chronic LP (χ² 7.980; p = 0.092). Herpesvirus infection is a significant risk factor for the development of acute LP.
Conclusion. Pityriasis lichenoides et varioliformis acuta (PLEVA) and chronic pityriasis lichenoides are rare and understudied diseases. The conducted analysis of statistical data forms demonstrated a trend of increasing incidence, indicating the need to identify risk factors for the onset and progression of PL, providing timely medical care, and preventing complications. The duration of the disease depends on the speed of establishing a final diagnosis a definitive diagnosis, necessitating the development of a diagnostic algorithm.

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