NeuroLearn NeuroHelp Metabolic @ Lysosomal storage disorders, classification
Background Gross Pathology Histopathology & Immunohistochemistry
BACKGROUND AND CLINICAL INFORMATION:
Head
Summary:
Gangliosides are present mainly in gray matter nuclei but not in any
significant amount in myelin. Gangliosidoses are due to failure in removing N-acetylgalactose
from the complex molecule during degradation.
Peripheral blood:
GM2 gangliosidosis (all)- no vavuolated lymphocytes.
GM1-gangliosidosis, infantile:
Numerous bold vacuoles in lymphocytes, abnormal
eosinophils.
GM1-gangliosidosis, juvenile: No vacuolated lymphocytes, although a few may be
seen.
Biochemistry:
GM2-gangliosidosis:
Hexaminidase
deficiency or deficiency of its activator proteins. Symptoms due to either
of the deficiency are similar.
GM1-gangliosidosis:
Deficient b-galactosidase
activity leading to accumulation of GM1-gangliosides.
HISTOPATHOLOGY AND IMMUNOHISTOCHEMISTRY:
Head
Histology:
Changes
in GM1- and GM2 gangliosidosis are similar.
There are ballooned neurons. In paraffin sections, PAS positive glial cells
but not neurons. In frozen sections, ballooned neurons are PAS+, Sudan black +,
and Luxol fast blue +. No LM changes in fetus up to 20 weeks of gestation. EM
can detect changes in fetus as young as 12 weeks of gestation.
NeuroLearn NeuroHelp Metabolic For Comment: KarMing-Fung@ouhsc.edu
Background Gross Pathology Histopathology & Immunohistochemistry