An ultrastructural study of lipodystrophia centrifugalis abdominalis infantilis, with special reference to fibrous long-spacing collagen

Lipodystrophia centrifugalis abdominalis infantilis (LCAI) in a 2.5-year-old Japanese girl is reported. Clinically she had a curved cu- taneous depression with a slightly elevated erythematous border on the left abdomen beyond the left groin. The regional lymph node was pal- pable. Histologic examination showed a decrease of the fat, an inflamma- tory infiltrate mainly composed of lymphocytes, and septal fibrosis in the subcutaneous tissue. Immunohistochemical analysis found that infiltrat- ing lymphocytes were mainly positive against CD4. Ultrastructurally nu- clei in the adipocytes were crescent shaped and located toward the pe- riphery of the cell. Some banded structures with a periodicity of 150 nm, and with intraperiodic bands, referred to as fibrous long-spacing collagen (FLSC), were observed in the septal area of the fatty tissue. These results indicated that FLSC was correlated with the breakdown of fibrillar colla- gens in LCAI.