Lichenoid papular eruption in a child. Frictional lichenoid dermatitis of childhood (FLDC)

Is frictional lichenoid dermatitis a minor variant of atopic dermatitis or a photodermatosis

“…Our primary hypothesis was that FLE is probably triggered and caused by sunlight and UV radiation. The marked aggravation in months with a high UV index as compared to winters has been reported in all studies[ 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 ] and is evidenced by the consistent use of “summer” aggravation in most studies [ Table 1 ]. We have statistically confirmed a correlation between the number of cases month wise with the UV index [ Table 4 ] which suggests that FLE is more common in the summer months.…”

“…[ 20 ] The recurrence of the dermatoses is probably a reason for their referral to dermatologists. [ 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 ] It was originally believed that friction is the probable cause[ 2 4 6 ] but this is probably a “nebulous”[ 6 ] and inconsistent finding. In our series, [ Table 2 ] friction had no role to play.…”

“…The purported relation to atopic dermatitis is not consistent and this is largely restricted to one study. [ 8 ] Other authors believe that it may be related to an underlying atopic state[ 5 6 8 9 ] and its label as a minor manifestation of AD[ 8 ] was probably as the diagnostic criterion used did not have the requisite sensitivity or specificity. [ 20 21 ] In fact in the study by Patrizi et al .,[ 8 ] the authors admit that it is difficult to confirm that FLE is a morphological variant of AD.…”

“…[ 20 21 ] This is important as this makes our analysis of the correlation of AD in relation to FLE more accurate than previous studies. [ 5 6 8 9 ] There are numerous arguments that suggest that FLE is unrelated to AD. Firstly most diagnostic criterion focus on minor criterions like FLE, which probably are unrelated to AD[ 20 21 ] The sites that are affected are usually the extensors[ 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 ] as opposed to the predominant flexural distribution in AD.…”

“…Firstly most diagnostic criterion focus on minor criterions like FLE, which probably are unrelated to AD[ 20 21 ] The sites that are affected are usually the extensors[ 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 ] as opposed to the predominant flexural distribution in AD. [ 17 ] FLE is largely asymptomatic[ 2 ] and importantly the summer or spring aggravation[ 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 ] is against the conventional aggravation of AD in winter months. Though various studies have found that a proportion of cases are either overt “atopics” or predisposed to “atopy”,[ 5 6 8 9 ] in our study only 17.2% of FLE cases were diagnosed as AD.…”