Acute rheumatism in children in its relation to heart disease.

Date:
1927
Catalogue details

Licence: Public Domain Mark

Credit: Acute rheumatism in children in its relation to heart disease. Source: Wellcome Collection.

    29/114 (page 17)
    streptococci obtained from sources quite unconnected with rheumatic infection.”’ The above examples are fairly representative and I think they suffice to justify the opinion, expressed at the beginning of this section of my report, that the inseolo gia evidence is conflicting and inconclusive. The main fact which emerges, as it seems to me, is that a definite answer may be returned to one question. Does viridans from rheumatic fever produce in the rabbit lesions which are clearly distinguishable from rabbit lesions caused by streptococci obtained from other sources? No. This is an important conclusion from the experimental work. It does not invalidate the claim of viridans but it helps to clear the ground. There is no use in attempting to push the claims of this organism by this particular method of attack. I do not think that resemblance or dissimilarity between certain myocardial lesions in the rabbit and Aschoff’s nodules can be regarded as a matter of any importance. Production of either acute or chronic arthritis in the rabbit means nothing. Such conditions may be caused by bacteria, belonging to the streptococcal and to other species, which have no relationship whatever with acute rheumatism. Serological Analysis of S. viridans. The tendency of the present day is to resort to serological methods for the precise identification of bacterial types. It is therefore natural to enquire whether the strains of wiridans which are thought to bear a causal relationship to acute rheumatism possess some serological characteristics which will distinguish them from strains not associated with this disease. This is a highly important subject, but perhaps it is not realised in. all quarters that it is extremely complicated. Organisms which are now called Streptococcus viridans are very common and are widely distributed. Search has been made —and is still being pursued—for a rational classification of them into types or sub-groups by means of serological analysis of their antigens. Results, so far, are not encouraging ; in fact it is not at present clear whether serological identification of these organisms is going to prove of much general utility. The nature of the difficulties will be readily understood in the light of what is already known about the serological classification of pneumococci. Types I, IJ and III are reasonably straight- forward,. but then there is a big residue, called Group IV, the members of which not only differ from the three “ fixed ”’ types but are heterogeneous amongst themselves. It is true that a certain amount of sub-grouping is possible within Group IV, but there always remain a number of individualistic strains which will not fallinto line. S. viridans, collectively, resembles the serological “scrap heap” of pneumococci called Group IV ;. indeed, the