Diagnosis Of Trachoma Research Articles

Getting to 2020: A Clinical Review of the Diagnosis, Treatment and Prevention of Trachoma

Objectives: 1) to undertake a review of the literature to provide information to clinicians and trainees about the epidemiology, treatment and most importantly, prevention, of trachoma - the leading infectious cause of blindness worldwide. 2) To highlight the diagnosis and treatment of this preventable infectious eye disease for trainees and to evaluate the efficacy of the SAFE treatment and prevention strategy endorsed by the WHO as the target trachoma elimination year of 2020 nears.
 Methods: A review of the literature was undertaken. PubMED, Clinical Key, UpToDate and Google Scholar databases were searched using the following MeSH terms and keywords: trachoma, infectious eye disease, chlamydia trachomatis, SAFE, community prevention.
 Results: The diagnosis of trachoma is typically clinical and is made by identifying the signs of conjunctival inflammation and scarring, trichiasis and corneal opacification in the context of a trachoma-endemic region. Randomized controlled trials have demonstrated the efficacy of the WHO’s SAFE (Surgery, Antibiotics, Facial Cleanliness, Environmental change) treatment and prevention strategy, the implementation of which has been associated with declining rates of trachoma worldwide.

Light out of deep darkness: a biography of Arthur MacCallan CBE, MD, FRCS

Arthur Ferguson MacCallan (1872-1955)was an ophthalmic surgeon who undertook his pioneering work in Egypt between 1903 and 1923. During that time, he established the ophthalmic hospital infrastructure in Egypt consisting of both travelling (mobile) and permanent hospitals, along with the training of surgeons. He also became a world authority on trachoma; the MacCallan Classification of Trachoma, initially published in 1908, was the first grading system used to standardise the diagnosis of trachoma and was later adopted by the WHO.

Direct fluorescent antibody assay and polymerase chain reaction for the detection of Chlamydia trachomatis in patients with vernal keratoconjunctivitis

OBJECTIVES:To identify Chlamydia trachomatis via polymerase chain reaction and a direct fluorescent antibody assay in patients with vernal keratoconjunctivitis while comparing the efficacies of both tests for detecting Chlamydia trachomatis in these conditions.METHODS:Conjunctival scraping samples were obtained from 177 patients who were divided into two groups: a vernal keratoconjunctivitis group (group A) and a control group (group B). The polymerase chain reaction and a direct fluorescent antibody assay were performed. Sensitivity, specificity, receiver operating characteristic curves, and areas under the curve were calculated for both tests in groups A and B. Receiver operating characteristic curves were plotted using a categorical variable with only two possible outcomes (positive and negative).RESULTS:Statistical analysis revealed a significant association between vernal keratoconjunctivitis and Chlamydia trachomatis infection detected by a direct fluorescent antibody assay with high sensitivity and specificity. All patients in group A with positive polymerase chain reactions also presented with positive direct fluorescent antibody assays.CONCLUSION:The association between vernal keratoconjunctivitis and Chlamydia trachomatis infection was confirmed by positive direct fluorescent antibody assays in 49.4% of vernal keratoconjunctivitis patients and by positive polymerase chain reactions in 20% of these patients. The direct fluorescent antibody assay detected Chlamydia trachomatis in a higher number of patients than did the polymerase chain reaction. Although the diagnosis of trachoma is essentially clinical, the disease may not be detected in vernal keratoconjunctivitis patients. Due to the high frequency of chlamydial infection detected in patients with vernal keratoconjunctivitis, we suggest considering routine laboratory tests to detect Chlamydia trachomatis in patients with severe and refractory allergic disease.

Epidemiologia do tracoma em povoado da chapada do Araripe - CE

To evaluate the epidemiological factors of trachoma in the Simão village. Through a field research, 412 individuals (178 men and 234 women) were examined in a village of the Araripe plateau in Ceará State. The median age was 34 years for both genders. Traditional data from trachoma epidemiology were collected and diagnosis of trachoma was performed using binocular loupes of x 2.5. 304 (73.8%) individuals were normal and 108 (26.2%) were trachomatous (5 TF, 98 TS, 3 TT and 2 CO). Regarding socio-economic factors relating to individuals, the illiterate were 1.9 times more likely to have trachoma (p<0.0001), but the more affluent were more affected (p<0.0001). As for the face appearance, the disease was more prevalent in patients with dirty faces (p=0.432). A difference was noted in multivariate analysis of socio-economic factors relating to housing; only the variable number of people per room, which was higher in the normal group (p=0.010). The good infrastructure found in the Simão village, especially the amount of houses with piped water and the good personal hygiene habits, favored the low findings of infectious forms.

Conjunctival impression cytology in trachoma

Trachoma is one of the leading causes of blindness and clinical examination remains the mainstay of diagnosis. However there is need to evaluate simple, inexpensive techniques which can be used for screening of trachoma in endemic regions. We report two cases where conjunctival impression cytology played a part in confirming the diagnosis of trachoma. We used a modified technique of obtaining conjunctival impressions, which not only met with better patient compliance and minimal ocular distress, but also provided better cellularity and morphology of cells for evaluation. The impression smears showed squamous metaplasia and loss of goblet cells. The cytoplasm of these cells had a hazy, moth eaten appearance and showed presence of intracytoplasmic inclusions. These basophilic inclusions were present singly and in clusters and were around 5 mum in diameter. A large number of these inclusions were present extracellularly as well. Conjunctival impression cytology is a simple procedure which needs to be evaluated for its potential to be used for screening trachoma in endemic areas.

The Medical Exclusion of an Immigrant to the United States of America in the Early Twentieth Century. The Case of Cristina Imparato

The medical inspection of immigrants arriving in the United States in the late nineteenth and early twentieth centuries was framed by a need to rapidly process large numbers of people. Scientific medicine, such as it was then, was subordinate to the existing immigration laws which reflected the influences of the powerful anti-immigration forces of eugenics and nativism. The line, or single-file queues in which immigrants were arranged, facilitated rapid processing. The split-second medical gaze was hailed by the then leadership of the U.S. Public Health Service as scientifically sound, based as it was on the alleged exceptional disease detection skills of examining public health physicians. In reality, this system was seriously flawed, led to numerous diagnostic errors, and was free of any form of public outcomes assessment or accountability. In time, trachoma became the principal focus of line physicians because of the belief that it could be easily detected, and those diagnosed with it summarily deported. However, the diagnosis of the early stages of this disease is far more complex since it must be differentiated from other forms of benign conjunctivitis. Described here is the case of Cristina Imparato, a 46-year-old immigrant who arrived in New York from Italy on September 27, 1910, and who was given a diagnosis of trachoma which resulted in her summary deportation three days later on September 30, 1910. Her case serves to illustrate the complex forces at work at that time around the issue of immigration. These included a need to meet the labor needs of expanding industries while responding to the immigration restriction demands of eugenics supporters and nativists and the call to protect the country from imported disease threats.

Quality assessment of conjunctival specimens for detection of Chlamydia trachomatis by PCR in children with active trachoma

One component of control programmes to eliminate trachoma is the treatment of Chlamydia trachomatis infection. A diagnosis of trachoma is based on clinical grounds, but the signs of active trachoma do not always correlate with the presence of C. trachomatis. During a therapeutic trial, the level of C. trachomatis infection in children with active trachoma in Guinea and Pakistan was assessed using a qualitative commercially available PCR that targeted the C. trachomatis plasmid. The influence of the quality of specimens on the efficiency of the PCR was investigated using two quantitative real-time PCRs targeting the specific omp1 gene of C. trachomatis and human chromosomal DNA, respectively. C. trachomatis was detected in c. 23% of children (aged 1-10 years) who presented with clinically active trachoma. Controls showed that PCR-related problems did not influence this detection rate. For 14% of the positive samples, C. trachomatis was detected in only one eye, with a significantly lower mean load of bacteria. These results suggest that epidemiological and therapeutic surveys should be conducted by sampling and testing both eyes. Moreover, the high variability of the cell load observed in the conjunctival swabs suggests that the effectiveness of swabbing may be questionable.

Clinical and Microbiological Diagnosis of Trachoma in Children Living in Rural Areas in the District of Attock, Punjab, Pakistan

Background: Trachoma is a sight-threatening process triggered by infection of the conjunctiva with Chlamydiae. When this infection becomes chronic and is associated with poverty it triggers trachoma, the prime cause of infectious blindness in the world. Since the 1958 report indicating that the highest incidence of trachoma in Pakistan was found in the province of Punjab, no new trials have been published. In the present study, we assessed the prevalence of trachoma in 3968 children living in 11 rural villages in the district of Attock, Punjab, Pakistan. The children with trachoma were sampled to detect C. trachomatis by PCR. Methods: Children in rural villages in the district of Attock were examined for trachoma in February 2004. Samples were obtained by scraping, and DNA was extracted (MagnaPure-LC Robot) and amplified to detect C. trachomatis (Amplicor-Roche). The quality of sampling was assessed by quantifying the number of cells by real-time PCR. Results: The prevalence of trachoma was 3.7% (0 to 6.2%). PCR was positive in 20% of samples from trachomatous children and the number of cells was always >100/sample. The income levels, illiteracy, use of latrines, water supply, and the presence of animals close to dwellings were similar in all the villages. In Sujjenda, the prevalence was doubled in the warmest season. Conclusions: Trachoma was diagnosed in 3.7% of the children aged <10 years. The low rates for positive PCR may be due to loss of the plasmid, the involvement of other Chlamydiae, or their absence in chronic infections. The results obtained here underestimate the prevalence of trachoma because most of the mothers (and babies) were not tested in the district of Attock.

Prevalence of trachoma in school children and ophthalmological outpatients in rural Egypt.

The prevalence of trachoma in school children and ophthalmological patients in rural villages of the Qalyub Governorate of Egypt was determined by clinical and laboratory diagnostic procedures and reported as mild, moderate, or severe according to the WHO classification scheme. Of 777 primary school students examined in 3 villages, 204 (26%) had clinically active trachoma. The overall prevalence of the disease in this population ranged from 16% to 35%. The prevalence of infection was higher in younger groups and decreased throughout primary school. Of 312 patients with ocular complaints examined at the village outpatient clinics, 100 (32%) had trachoma infections. Monoclonal FA staining showed higher sensitivity in detecting positive cases of trachoma than did Giemsa staining. This study has shown that trachoma is still prevalent in rural Egypt and that the monoclonal FA staining is a relatively sensitive and practical test for the laboratory diagnosis of trachoma in a field study, where reasonable facilities for culture diagnosis are not available.

Accidental Human Trachoma with Rapid Diagnosis by a Cell Culture Technique

The diagnosis of trachoma can be easily established in the typical case, by using the specific clinical criteria well summarized recently by Thygeson¹and by finding Halberstaedter-Prowazek inclusion bodies in a smear of epithelial scrapings. There are many clinically doubtful cases, however, in which the diagnosis is difficult to make. This is particularly true when the question of a recurrence arises in a case of healed trachoma with residual scarring. It has also been found that in surveys made to reveal the true incidence of trachoma in a population, or to study its treatment, the presence of nontrachomatous chronic follicular conjunctivitis can confuse the picture, particularly in the diagnosis of very early trachoma.²It is clear that improved methods are needed for detecting trachoma infection. A good laboratory method would be especially useful in those trachomatous populations that do not have the services of trained ophthalmologists. Other than

Bulletin of the Ophthalmological Society of Egypt.

This issue of the Bulletin of the Egyptian Ophthalmological Society contains more than thirty articles dealing with a great variety of topics and varying considerably as to quality. In the surgical field Dr. Tobgy reviews the recent operations for retinal detachment, describes a method of extraction of cataract with electrocoagulation and reports several cases in which plastic operations were performed on the lower lid. As usual, there are several articles devoted to trachoma. Dr. Peter Olitsky (Rockefeller Institute, New York) reports the finding of a micro-organism which he believes is responsible for spontaneous folliculosis in monkeys. Another contribution in the same field describes the differences in vascularization in spring catarrh and in trachoma; another concludes that Tricoire's reaction (measuring the sensitivity of the skin to an injection of material from trachoma follicles) is of no value in the diagnosis of trachoma. The various xerotic changes met with in

Laboratory diagnosis of trachoma

G. B. Stepanov reports the results of a study on the presence of Proryazek'a bodies in 786 cases, of which 655 were examined with trachoma con'yunctiva scrapings, 58 with follicle contents from trachoma patients and 73 with con'yunctiva scrapings from non-trachoma patients.

The reaction of binding of complement with adenoid antigen in trachoma

Vancea (C. r. De la Soc. De Biol., 1925, No. 4) repeated Sojrosso's studies with an adenoid antigen to produce a complement fixation reaction in trachoma, and he made sure that this reaction could not be used for the differential diagnosis of trachoma.

The clinical course and the diagnosis of trachoma

The clinical course and the diagnosis of trachoma

The Laboratory in Practice — Exhibit of Industrial Conditions — The Diagnosis of Trachoma — International Congress of Hygiene and Demography — Medical Notes

Editorial from The New England Journal of Medicine — The Laboratory in Practice — Exhibit of Industrial Conditions — The Diagnosis of Trachoma — International Congress of Hygiene and Demography — Medical Notes