PMC5968237_01
Clinical features. a, b At 10 years of age. Hyper- or hypo-pigmented plaques around the right thigh (a) and shin (b). c At 14 years of age. Atrophic macules and pigmentations with slight subcutaneous tissue reduction around the right knee.
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F1
Examination revealed confluent hyper- or hypo-pigmented plaques that extended from the right thigh to the ankle without non-pitting edema (Fig. 1a, b) and a 4-cm diameter hypo-pigmented plaque on the left lower abdomen. At 14 years of age, atrophic macules with mild subcutaneous tissue reduction remained on his right leg (Fig. 1c).
Histopathological findings. a Skin biopsy. Fibrosis with thickened collagen bundles in the dermis and superficial subcutis (hematoxylin and eosin stain; original magnification x40). b Light microscopy examination of kidney biopsy. Mild mesangial hypercellularity and large blue-stained hyaline deposits in the afferent arteriole (arrow) (Mallory-Azan stain; original magnification x400). c Immunofluorescence microscopy examination of kidney biopsy. Diffuse linear capillary wall deposits (immunofluorescence stain using antiserum to IgG; original magnification x200). d, e Electron microscopy examination of renal glomeruli. Large electron-dense deposits in the afferent arteriole at the vascular pole (original magnification x500 in d and x1,500 in e).
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F2
A skin biopsy specimen showed vacuolization of the basement membrane, perivascular inflammatory infiltration, and fibrosis with thickened collagen bundles in the dermis and superficial subcutis (Fig. 2a). Large hyaline deposits were seen in the afferent arteriole of the vascular poles in 3 glomeruli (Fig. 2b). Immunofluorescence microscopy documented linear staining along the glomerular capillary walls for immunoglobulin (Ig)G (2+), IgM (2+), C3 (2+), and IgA (1+) (Fig. 2c). However, electron microscopy (EM) did not show immune deposits either in mesangial areas or capillary walls, and revealed large electron-dense deposits (EDD) in the afferent arteriole, which corresponded to the hyaline deposits observed by light microscopy (Fig. 2d, e).
The clinical course. Skin, articular, and renal manifestations appeared successively. Skin and articular manifestations improved before the renal findings disappeared.
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F3
The urinary findings disappeared approximately 5 years after the first observed manifestation (Fig. 3).