Transcript Pathology of mucin

Pathology of Mucin
Jaroslava Dušková
Inst. Pathol. ,1st Med. Faculty,
Charles Univ., Prague
Mucin
glycosaminoglycans & glycoproteins
ground substance of mesenchymal tissue –
hyaluronic acid, chondroitinsulphate…
Source: fibroblasts
Reg.: corticoids, thyroxin, vit. C…..
 epithelial – hexosamins, sialic acid, fucose…
Source: epithelia cells ( goblet, foveolar…)
Reg.: external irritation, inborn defects mucoviscidosis

Mucin - morphology
Macroscopy:

gelatinous in larger deposits
 catarrh
Microscopy:
 mucikarmine
 alcian Blue
 PAS (positive following amylase pretreatment)
Myxoid Degeneration
Definition:
accumulation
of the glycosaminoglycans
in the ground substance
of the tissue
Myxoid Degeneration




hypothyroidism (exc. hyperthyr.)
Marfan´s syndroma (aorta, valves)
ganglion
floppy valve syndrome
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
Epithelial Mucin - pathology

overproduction – acute inflammation
„catarrh“

decreased production – chronic
inflammation with mucose atrophy


changed quality - mucoviscidosis
preserved production - neoplasms
Mucoviscidosis
cystic fibrosis, fibrocystic disease

autosomal recessive 7th chromosome
2-5% heterozygotic carriers in the caucasian
population

abnormal viscosity of mucin
– disturbance of the membrane associated
protein that serves as a calcium channel


increased concentration of chloride in sweat
decreased water content in excocrine secrets
Mucoviscidosis
cystic fibrosis, fibrocystic disease
Complications:
–
–
–
–
meconium ileus
steatorrhea
pancreatic fibrosis & cysts
bronchitis, bronchopneumonia,
bronchiectasia
– sterility
Epithelial Mucin - pathology
Complications -1.

overproduction :
–
–
–

nonneoplastic cysts
neoplastic cysts
mucophagic granulomas
decreased production:
–
–
impaired trophic of the mucose
dysplastic changes
Epithelial Mucin - pathology
Complications -2.

changed quality:
–
infection, cysts, scaring

preserved production in neoplasms:
–
aid for diagnosis