1. Pathology of Mucin Jaroslava Dušková Inst. Pathol.,1st Med. Faculty, Charles Univ., Prague

2. Mucin glycosaminoglycans & glycoproteins u ground substance of mesenchymal tissue – hyaluronic acid, chondroitinsulphate… Source: fibroblasts Reg.: corticoids, thyroxin, vit. C….. u epithelial – hexosamins, sialic acid, fucose… Source: epithelia cells ( goblet, foveolar…) Reg.: external irritation, inborn defects - mucoviscidosis

3. Mucin - morphology Macroscopy: u gelatinous in larger deposits u catarrh Microscopy: u mucikarmine u alcian Blue u PAS (positive following amylase pretreatment)

4. Myxoid Degeneration Definition: accumulation of the glycosaminoglycans in the ground substance of the tissue

5. Myxoid Degeneration u hypothyroidism (exc. hyperthyr.) u Marfan´s syndroma (aorta, valves) u ganglion u floppy valve syndrome

6. Storage Diseases Def.: inborn errors of metabolism (mostly single gene abnormality) leading to an enzyme defect with subsequent accumulation of the substrate (& lack of the product) in tissues or organs

7. Epithelial Mucin - pathology u overproduction – acute inflammation „catarrh“ u decreased production – chronic inflammation with mucose atrophy u changed quality - mucoviscidosis u preserved production - neoplasms

8. Mucoviscidosis cystic fibrosis, fibrocystic disease u autosomal recessive 7th chromosome 2-5% heterozygotic carriers in the caucasian population u abnormal viscosity of mucin –disturbance of the membrane associated protein that serves as a calcium channel v increased concentration of chloride in sweat v decreased water content in excocrine secrets

9. Mucoviscidosis cystic fibrosis, fibrocystic disease Complications: – meconium ileus – steatorrhea – pancreatic fibrosis & cysts – bronchitis, bronchopneumonia, bronchiectasia – sterility

10. Epithelial Mucin - pathology Complications -1. u overproduction : – nonneoplastic cysts – neoplastic cysts – mucophagic granulomas u decreased production: – impaired trophic of the mucose – dysplastic changes

11. Epithelial Mucin - pathology Complications -2. u changed quality: – infection, cysts, scaring u preserved production in neoplasms: – aid for diagnosis