Biomedical subjects
Publications and source records attributed to J Schachter.
Fifty cat scratch disease patients were tested for antibodies against candidate etiological agents, with inconclusive results. Future research should emphasize new viral isolation methods to discover the elusive agent.
In two villages in southern Tunisia where trachoma was endemic 7 per cent and 14 per cent of adults respectively had visual acuity of 20/400 or less. In both villages active trachoma affected most children under the age of two, reached a peak in two- to five-year-olds, then declined to age 15. The chronic inflammatory disease in childhood appeared to produce irreversible scarring of the eyelids, and loss of vision occurred in adult life due to corneal scarring caused by inturned eye lashes and loss of tears (dry-eyed syndrome). Economic development in one village was associated with a decline in active, infectious disease. In the second village, whose traditional economy was unchanged, there was the same prevalence of active disease over a three-year period. Unless economic development or public health control programmes reduce the prevalence of severe and moderate trachoma children now affected will develop the same blinding lesions as their parents. With the increasing numbers of children who survive there will probably be a dramatic increase in the numbers of the blind from trachoma in 10 to 20 years. Since active inflammatory trachoma in childhood responds to tetracyclines, erythromycin, and sulphonamides the disease should be attacked in those undeveloped rural areas where it continues to lead to blindness.
Chlamydiae are being increasingly recognized as an important cause of human disease. The known geographical distribution of lymphogranuloma venereum and the role of chlamydiae as agents of sexually transmitted diseases are reviewed. The presence of chlamydiae in the urethra and the cervix, and their etiological relationship to genital infections, first recognized in connexion with ocular infections, have been proved in a number of studies in selected populations in a few countries. Chlamydiae appear to be the most important agent of nongonococcal urethritis, which in some cases appears now to be more frequent than gonococcal urethritis. In addition to their association with cervicitis, chlamydiae appear also to be fairly frequent in the cervix of apparently normal, asymptomatic, and sexually active women. The role of chlamydiae as agents of other human diseases still requires to be clarified. The organisms have been found in association with pelvic inflammatory disease, neonatal pneumonia, pharyngitis, and otitis. There is need for additional studies in view of the fact that effective chemotherapy is available. An outline is given of laboratory methods that may be useful for the diagnosis of chlamydial infections.
Sixty-one full-term, appropriate-weight black newborns had higher heart rates, replicating a racial heart rate difference, but did not differ significantly in systolic blood pressure from 71 white newborns. Systolic blood pressure in the newborn is related both to the total number of feedings from birth and to the total fluid intake.
The prevalence of antibodies to chlamydiae, particularly to TRIC (trachoma-inclusion conjunctivitis) agents, was studied in women with cervical dysplasia and in women attending selected clinics (obstetrics, cancer-screening, and gynecology). In addition, attempts were made to isolate TRIC agents and herpesviruses from the cervices of these women. TRIC agent recovery rates 4.1 per cent for women with dysplasia, 5.4 per cent for pregnant women, 7.8 per cent in the women's clinic, and 0.8 per cent in the cancer-screening clinic. Herpesvirus recovery rates were lower, on the order of 1 per cent or less in each clinic. Complement-fixing antibodies to chlamydial group antigen were detected in 21.5 per cent of women with dysplasia. With a more sensitive fluorescent antibody method, 77.6 per cent of the women with dysplasia or cervical cancer were shown to have antibodies to chlamydiae. In general, antichlamydial antibodies were less prevalent in the other clinic populations. The results of this study indicate that women with cervical dysplasia or cancer may have a high prevalence of antibodies to sexually transmitted agents other than herpesvirus type 2.
We studied two population groups (more than 1,600 patients) to determine the prevalence and clinical associations of genital tract infections with chlamydiae and herpesviruses. Base-line isolation rates for asymptomatic women having routine pelvic examinations were much lower than rates for symptomatic women. In both groups, chlamydiae were more prevalent than herpesviruses. Chlamydial infection was associated much more commonly with cervicitis (36.6%) than with vaginitis only (4.1%). Among 282 symptomatic men, the cultures of 19.9% yielded chlamydiae, and 4.3%, herpesviruses. Chlamydiae were recovered from 35.5% (27 of 76) of specimens from men with nongonococcal urethritis, and from an even larger proportion, 57% (24 of 42), of the specimens from men with frank discharge.
A controlled chemotherapy trial of trachoma was carried out in a Tunisian oasis among schoolchildren with active disease. We compared 1% tetracycline ointment (79 patients) or 1% rifampicin ointment (76 patients) with 5% boric acid ointment (79 patients). Medications were administered twice daily, six days a week, for ten weeks. Slit-lamp examinations by three ophthalmologists were made independently before treatment as well as five, 19, and 39 weeks after treatment. Bacteriologic cultures were taken during treatment as were smears to detect trachoma agent at each clinical examination. Five weeks after treatment, the intensity of conjunctival disease in the tetracycline and rifampicin groups was reduced significantly when compared with boric acid, but at 19 weeks this suppression was found only in the tetracycline group. Ocular bacterial pathogens were eliminated almost entirely in the two antibiotic groups during treatment. The initial prevalence of trachoma (29to 31%) was significantly reduced in the two antibiotic-treated groups at five weeks and 19 weeks after treatment. The prevalence of trachoma was equally low (7%) in all three groups following retreatment with tetracycline. Although both antibiotics were effective, rifampicin offered no advantage over tetracycline in this trial. Recurrent disease in this school-based treatment study probably was due to reinfection from younger siblings at home. While systematic, community-wide, antibiotic treatment programs are not always possible in countries where trachoma is endemic, limited antibiotic therapy programs should be continued in these areas to reduce the intensity and prevalence of trachoma, even though the disease cannot be eradicated.
A recent publication of the National Center for Health Statistics estimated the prevalence of asthma in 1970 to be 30.2 per 1,000 noninstitutionalized population, and of hay fever (without asthma) as 54.2 per 1,000. These and other data on chronic respiratory conditions were obtained by means of a household survey employing lay interviewers and a standardized questionnaire. There may be a gap between the intended meaning of the key question-did the individual have a chronic condition during the past 12 months-and the respondent's understanding of it. As a consequence, some of those who have been asymptomatic in the recent past may have excluded themselves. Even among people with the chronic condition who have seen a physician about it during the prior year, significant numbers fail to report it to the interviewer, according to validation studies. A method is suggested for making rough adjustments for these undercounts. It results in raising the estimated prevalence to 43.0 for asthma and 71.1 for hay fever. These revisions are dependent on necessarily subjective assumptions about the magnitude of the biases involved.
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A pregnant woman and her husband had proved chlamydial genital tract infections. She gave birth to a male infant who developed inclusion blennorrhea (inclusion conjunctivitis of the newborn infant). While on topical chemotherapy for his eye disease, the infant developed pneumonitis. Chlamydiae were recovered from his sputum at a time when conjunctival specimens were sterile. This finding raises the possibility that the agent of inclusion conjunctivitis may cause systemic infections in neonates exposed during passage through an infected birth canal.
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Chlamydial isolates of bovine origin were serotyped by a plaque reduction method. Of the two major serotypes observed, type 1 included isolates from bovine abortion and enteric infections, whereas type 2 isolates were associated with polyarthritis or encephalomyelitis. These two serotypes were identical to those with a similar disease distribution previously observed in isolates of ovine origin. The two groups did not cross-react and they were serologically unrelated to chlamydiae of avian origin. Thus, it appears that many chlamydial isolates causing intestinal infections or abortion in sheep or cattle are closely related antigenically, as are those producing polyarthritis, encephalomyelitis, and conjunctivitis, and that the two groups are distinct.
Microscopical examination of 927 Giemsa-stained conjunctival smears from children with chronic trachoma in southern Tunisia showed 93 (10 per cent.) with typical trachoma (chlamydial) inclusions in epithelial cells. The accompanying cytological features were a useful indicator for inclusions. Inclusions were found only in slides with numerous polymorphonuclear neutrophils (PMNs) and separation of the epithelial cells. When these two features alone were present, 3 per cent. of the smears were inclusion-positive; when many lymphocytes were present also, 25 per cent. were inclusion positive; when other cytological features (plasma cells, macrophages, blastoid, and stem cells) were present as well, 70 per cent. of the smears were inclusion-positive. The occurrence of these sets of cytological features can be a useful guide for selecting smears for intensive examination for chlamydial inclusions. Immunofluorescent (FA) staining and Giemsa staining of 527 pairs of matched smears detected trachoma agent in 67 (13 per cent.); in thirty by both methods, in thirteen by Giemsa staining alone, and in 24 by FA alone. The examination of Giemsa-stained smears for chlamydial inclusions is a useful technique for the diagnosis of trachoma or inclusion conjunctivitis by laboratories that do not have the specialized facilities for the identification of these chlamydial infections by the technically more complex procedures of immunofluorescent staining or isolation in embryonated eggs or tissue cultures.
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Eight chlamydial isolates of ovine origin were tested in a plaque reduction system using homologous and heterologous rooster antisera. The eight isolates could be separated into two separate immunotypes. Type 1 included isolates associated with ovine abortion and one agent recovered from the feces of an apparently normal sheep. Type 2 isolates were associated with polyarthritis and conjunctivitis. These two serotypes were not cross-reactive with several chlamydiae of avian origin. Further application of the plaque reduction test may provide a useful means of typing chlamydiae.
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