Quantitative determination of hexosamine in cardiac valves in the case of so-called serous endocarditis
Geiler, G.; Fischer, C.
Zentralblatt für Allgemeine Pathologie U. Pathologische Anatomie 121(4-5): 420-428
1977
ISSN/ISBN: 0044-4030 PMID: 919826 Document Number: 117512
Histochemical and immunhistochemical studies prove that serous endocarditis is not a serous inflammation, but mucoid valvular swelling due to an accumulation of acid glycosaminoglycans. Acid glycosaminoglycans were biochemically determined by a quantitative determination of the hexosamine content. A total of 84 hearts were examined, and their valves were classified into 4 groups (normal valves, valves showing mucoid swelling, valves with strongly marked mucoid swelling, valves showing mucoid swelling with regression due to formation of fibrous tissue). Hexosamine content was analyzed in dependence upon the results of macroscopic examinations. In 33 cases parallel histochemical examinations were made on the same heart valves in an effort to detect the presence of acid glycosaminoglycans. Mucoid valvular swelling, as judged from the hexosamine content, was due to a marked increase in acid glycosaminoglycans. The hexosamine content of cardiac valves with strongly marked mucoid swelling, was an average of 1.16 mg%. This was nearly twice as high as in normal valves. Histochemical results also correlated well with this finding. The origin of acid glycosaminoglycans and their synthesis by local connective tissue cells was discussed. Mucoid swellings were characterized in dependence on both the extent of the swelling and the local structural consequences. Large areas of swelling accompanied by damage to cellular and fibrous tissue was regarded as catabolic dystophy. Mucoid valvular swelling appears to be a location-dependent form of mucoid degeneration observed in connective tissue at other sites.