Disorders of Fat

Focal dermal defect: localized areas of atrophic skin with laxity or herniated appearance over trunk, thighs and arms, ± overlying skin depressed or macular

Normal epidermis, ↓ or absent elastic tissue in dermis with special stain (may appear normal on H&E), ± perivascular lymphocytes

May be primary (idiopathic) or secondary (infection, inflammatory cutaneous disorder or tumor)

Single to multiple well-demarcated oval hyperpigmented patches with slight depression on back (most common) in young adults and adolescents

{If linear following Blaschko’s lines → atrophoderma of Moulin}

Minimal change including flattening of rete ridges, basal layer with ↑ melanin, ↓ dermal thickness, ± perivascular infiltrate

Unclear if atypical atrophic form of morphea or separate entity; may be related to B. burgdorferi

Areas with diffuse fine wrinkling over trunk, upper arms and/or neck, ± preceding erythema

Normal epidermis, selective loss of elastic fibers in mid dermis

None

Dimple-like depression in follicular orifices consistent with ice-pick depressions on dorsal hands/feet or cheeks

Dilated pore ± with underlying atrophy, often ↓ elastic fibers

{If limited to cheeks → atrophoderma vermiculatum (Rombo syndrome, Nicolau- Balus syndrome)}

Bazex syndrome

Conradi-Hünermann- Happle syndrome

Skin-colored papules in heels with pressure (due to herniation of fat), disappears when weight removed

Fragmentation of dermal elastic tissue and herniation of fat into dermis

Normal variant