The “terra-firma-forme” dermatosis (TFFD) is a benign dermatosis with chronic development, affecting in particular children and teenagers. Often it is mistaken with dermatitis neglecta, an illness due to insufficient hygiene.
Nine patients, 7 girls and 2 boys aged 5 to 16 were consulted over a 12-month period, motivated by aesthetic embarrassment produced by maculous or brown papulous pigmentation located mainly on the anterior and lateral neck and retroauricular, and rarely on the presternal region, periumbilical and thigh regions.
The clinical aspect, the persistence of the pigmentation despite the washing with water and soap, and its disappearance with a 70° alcohol-soaked compression have established the diagnosis of terra-firma-forme dermatoses (TFFD).
TFFD is a common, but little-discussed, topic in specialty literature, which is why it is little known. Clinically it presents itself as pigmented macules or papules, sometimes hyperkeratotic, brownish, isolated or conflated, localized bilaterally and symmetrically, particularly on the anterior and lateral sides of the neck, the retroarticular region, ankles, the medial portion of the body. Histology is not necessary.
The specifity of TFFD consists in its persistence even with aggressive washing with water and soap, and the disappearance with repeated and pressed friction with a 70° alcohol or ether compression, the compression gaining a dirty appearance.