LAUSR

To the Editor: I read with interest the recent article by Rosman et al, which assessed the prevalence data and clinical characterization of chronic urticaria in adolescents, by taking advantage of the medical records of the mandatory military medical screening in Israel. Based on thesemedical records of 1,108,833 consecutive 16-year-old conscripts undergoing military visits from 1996 until 2015, these authors retrieved data for 6617 adolescents (0.6% of the total) diagnosed with chronic spontaneous urticaria (CSU). According to the most updated definition, CSU is characterized by the ‘‘spontaneous appearance of wheals, angioedema or both for [6 weeks due to known ( for example, auto-reactivity that is the presence of mast cell-activating auto-antibodies) or unknown causes.’’ The authors stated they excluded all forms of inducible or secondary urticaria and described the comorbidities of CSU in their cohort of adolescents, without suggesting or discussing any pathophysiologic link or causal relationship between 2 associated clinical conditions. Indeed, for instance, the fact of being asthmatic does not exclude necessarily the diagnosis of CSU in a patient with chronic urticaria. However, it is equally true that the epidemiologic analysis and methodology of this study may not have afforded the authors the ability to always establish the precise diagnostic conclusions about the specific form of chronic urticaria in each affected patient. Therefore, inmy opinion, the yearly prevalence of 0.4% to 0.8% extrapolated by the authors may not refer to CSU only, because there is the possibility that other forms of chronic urticaria might be included as well in this count due to the study methodology. According to different studies, the prevalence of chronic urticaria in the pediatric population ranges from 0.1% up to 3%. Pediatric CSU is considered to be much less prevalent than in adults. Previous articles