Prenatal pathology in mucopolysaccharidoses: a comparison with postnatal cases.

Morphologic data from four fetal cases of mucopolysaccharidoses (2 MPS 1 H, 1 MPS 2, 1 MPS 3 A) are compared with six postnatal observations (2 MPS 1 H, 1 MPS 1 H- 1S, 1 MPS 2, 1 MPS 3A, 1 MPS 3C) and to age-matched controls. Since most of the lesions are difficult to analyze in fetuses by light microscopy, standard electron microscopic techniques have been used to check the structure of representative levels in the nervous system and visceral organs. The following conclusions are drawn in this comparative study: (1) prenatal MPS cases are already affected at an early fetal age; (2) in affected fetuses, the intraneuronal storage is much more severe in the more mature neurons, e.g., anterior horn cells, spinal ganglionic, and myenteric neurons; and (3) fetal types cannot be individualized by morphologic techniques, any more than the postnatal MPS 1, 2, and 3 cases.