Dermal elastic fibres in the inherited hypermobile disorders.
BACKGROUND
Elastic fibres in the inherited hypermobile disorders are probably abnormal on the inherited grounds. The abnormality may contribute for diagnosis and investigation of connective tissue biology.


OBJECTIVE
The abnormality will be specific for every disorders and disclosed in the age-dependent change when exposure-dependent change was excluded.


METHODS
Skin specimens from Ehlers-Danlos syndrome and hypermobile syndrome, Marfan syndrome, Osteogenesis imperfecta type I, homocysteinuria and normal controls are studied by routine electron microscopy. Age-dependent ultrastructural change of broad elastic fibres was evaluated in reticular dermis.


RESULTS
Age-dependent change was categorized in infantile, adolescent, adult and senile pattern. Infantile pattern showed normal ultrastructure. Degeneration was first found in adolescent pattern by disarrayed microfibrils and degenerate matrix. Degeneration proceeded in adult pattern and ended in senile pattern. Typical abnormality developed in adult pattern. Ehlers-Danlos syndrome and hypermobile syndrome showed no specific abnormality but the degeneration began earlier and was severer than the control. Marfan syndrome showed defects of microfibrils and matrix surface. Moth-eaten figure was characteristic. Osteogenesis imperfecta showed abnormal matrix and revealed homogenous bulges of matrix. Homocysteinuria was specified by numerous microfibrils on the matrix surface in infantile pattern.


CONCLUSIONS
Abnormality of elastic fibre was recognized in the reticular dermis of elbow. Ehlers-Danlos syndrome and hypermobile syndrome showed no specific abnormality but the degeneration was more intensive than the control. Abnormality of Marfan syndrome was degeneration of elastic microfibrils and matrix surface, Osteogenesis imperfecta was characterized by excess amount of matrix. Homocysteinuria revealed numerous microfibrils. Ultrastructural abnormality provided grounds for studies on histopathology and biology of elastic fibre.
Kobayasi
Takasi
T
Department of Dermatology, University of Copenhagen, Bispebjerg Hospital, D-92, Bispebjerg Bakke 23, Copenhagen NV DK-2400, Denmark. kobayasi@mail.dk
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D003238:Connective Tissue; D020405:Dermis / Q000378:metabolism; D004535:Ehlers-Danlos Syndrome / Q000378:metabolism; D004548:Elasticity; D004550:Elbow; D005260:Female; D006712:Homocystinuria / Q000235:genetics; D006801:Humans; D007223:Infant; D008382:Marfan Syndrome / Q000378:metabolism; D008854:Microscopy, Electron; D008875:Middle Aged; D010013:Osteogenesis Imperfecta / Q000235:genetics; D012867:Skin / Q000378:metabolism / Q000473:pathology*