Laboratory Studies
Mutation analysis of the KIND1 gene can be performed.
Histologic Findings
Histopathologic examination of atrophic skin lesions in patients with Kindler syndrome reveals nonspecific features of poikiloderma. The epidermis is flattened and atrophic, edema is present at the dermoepidermal junction, and the basal layer shows focal vacuolization with basal cell degeneration. Other histologic features include a prominence of dermal capillaries, pigmentary incontinence, and, possibly, perivascular lymphocytic infiltrate.
Immunostaining with anti–kindlin-1 antibody is a new and useful diagnostic test in the assessment of suspected cases of Kindler syndrome; decreased staining of the epidermis of patients with Kindler syndrome is observed compared with controls. [7]
Electron microscopy shows reduplication and disruption of the lamina densa with attached anchoring fibrils along the dermoepidermal junction and cleft formation in the lamina lucida, suggestive of continual remodeling of the basement membrane zone. Ultrastructural studies of bullae in the skin of affected persons have demonstrated a coexistence of 3 levels of abnormal cleavage: (1) within or just above the basal layer of epidermis (intraepidermal), (2) within the lamina lucida (junctional), and (3) below the lamina densa (dermal).
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Images show the progression of lesions. A and B: At birth, acral blisters and erosions are present. C and D: At age 5 years, atrophy and reticulated erythema with dyschromic patches are noted. E and F: At age 7 years, progressive poikilodermatous changes with reticulated erythema and telangiectasia occur. G and H: At age 10 and 15 years, poikiloderma with telangiectasia and depigmentation are observed. Excoriations are due to pruritus. Reprinted from Yasukawa K, Sato-Matsumura KC, McMillan J, et al: Exclusion of COL7A1 mutation in Kindler syndrome. J Am Acad Dermatol 2002 Mar; 46(3): 447-50. Courtesy of the American Academy of Dermatology.