Studies on Trachoma
Authors: Weiss Charles , BOWERS GARVEY B. 
Published: January 2023

Discussion and Summary
The sera of 55 trachoma patients were tested against two strains of Bact. granulosis (Tu. 3.4 and MC) and 40 of these against strain 1R. Twenty-six “control” sera, obtained from miscellaneous patients, including types of conjunctivities and other diseases of the eye, as well as from normal persons and a variety of surgical cases, were also examined. Certain sera were found to agglutinate Bact. granulosis in dilutions of 1:4 to 1:100 which was the highest dilution tested.
The three strains of Bact. granulosis behaved somewhat differently in their agglutinability with patient's sera. Thus strain MC agglutinated with 17 out of 55 “trachoma” sera while strain Tu. 3.4 reacted with only 8, and strain 1R agglutinated with 6 out of 41. Sera which were allowed to age in the icebox were often reduced in agglutinin titer and occasionally gave negative results.
The results recorded in the tables indicate that in a general way agglutination of Bact. granulosis occurs more frequently in the sera of trachoma patients than that of normal individuals. The agglutination appears to occur to a higher dilution of serum from trachoma patients. Moreover, several points are of interest. Thus, serum 37, obtained from a Negro with normal conjunctivae, showed a high agglutinin titer (1:100 ++, table 2). It will be recalled that Testa (22) and others observed that full blooded Negroes are immune to trachoma. (This writer has suggested the use of Negro blood in the treatment of trachoma.) Patient 57, was suffering from a conjunctivitis of undiagnosed type at the time when her blood was taken, and being a nurses' assistant at the Presbyterian Hospital for Navajo Indians, she was constantly exposed to infection with trachoma. Her serum titer was 1:100+++.
An attempt was made to analyze the agglutination reactions of the “trachoma” sera with reference to the age, race and sex of the patient, the stage and duration of the disease, the presence of follicles or of conjunctival scars, of pannus or of mixed infections, but the total number of patients was insufficient to warrant any conclusions.
For the purpose of comparison, the literature on immunological reactions in other infections of the eye was reviewed. It was noted that, in general, these localized infections do not cause appreciable antibody production. Thus, Reis (23) observed that in infections on the conjunctiva due to the diplobacillus of Morax, the serum manifested no increased bacteriolytic or bacteriocidal properties. Likewise, the conjunctival secretions in this disease had no increased phagocytic activity. zur Nedden (24) similarly observed negative results in phagocytic experiments with conjunctival secretions due to the pneumococcus and to the Koch-Weeks bacillus. It is remarkable that even in a case of panophthalmitis due to a diplococcus, Bach (25) was unable to demonstrate specific agglutinins in the serum of the patient. It is only when the ocular infection is part of a generalized or systemic disease that serum antibodies are demonstrable. Thus, complement fixing antibodies were found by Reber and Lawrence (26) and by Edmund (27) in the serum of patients suffering with iritis of gonorrhoeal origin, while agglutinins in fairly high concentration (1:140 to 1:320) were observed by Vail (28) and by Dvorak (29) in patients having the oculo-glandular type of tularemia. Similarly, Pascheff (30) who described a new type of infectious conjunctivitis, due to a specific coccobacillus, observed an agglutinin titer of 1:2000. This disease is similar to tularemia in its glandular and febrile manifestations.