Abstract
It has been known for a long time that there are certain exceptions to the common blood grouping. This was pointed out repeatedly by one of the writers 1 as well as by others. 2
It did not seem worth while to describe in detail some observations which we have made along this line since, at the present time, there is no practicable way of comparing such disconnected findings with similar ones of other workers and properly classifying them.
In our studies we have found instances of weak agglutination of a serum type I with another blood of the same type and recorded similar reactions with specimens of types II and III.
The reactions were chiefly observed at a temperature of about 15° C. or less. At higher temperatures they became gradually weaker and disappeared. Several times the clumps contained rouleaux.
The observation that at lower temperature atypical agglutinin reactions may occur between human bloods and sera of different individuals has already been described by Bialosuknia and L. Hirzfeld. 3 While the conclusion of these authors that the reactions are different from isoagglutination is questionable, they certainly gave a description of the fact. Similar phenomena were described in detail by Guthrie and Pessel 4 Although it is possible that an agglutination of this kind would not occur at body temperature yet the slight difference in the constitution of the blood might be sufficient to produce undesirable effects. Regarding the practical application, the observations suggest the use of direct cross tests before transfusion (in addition to typing); furthermore, it seems advisable to make these tests at low temperatures since in that way slight reactions may appear. This deduction has previously been made by Gutlirie and Pessel.
Difficulty may be experienced in distinguishing isoagglutination at low temperatures from autoagglutination since the latter is favored by decreasing temperature. 5
Get full access to this article
View all access options for this article.