Excess mortality associated with blindness in leprosy patients in Korea

Vision loss and blindness are potential complications of leprosy. There is little data available to indicate the impact of eye complications on life expectancy and quality of life. We sought to determine the relative risk of death in blind leprosy patients compared to nonblind leprosy patients. A population-based ocular survey of 510 mycobacteriologically negative leprosy patients in rural South Korea, conducted in 1988, formed the study population. After a 7-year period patients were traced to determine their status (alive, dead, lost to follow up). Blind patients showed a 4.8-fold risk of death, even after adjusting for other factors, compared to nonblind patients. Young blind leprosy patients had the highest relative risk of death. Excess mortality was not associated with any specific cause of blindness, ocular pathology, or type of disease. Findings from our study suggest that all leprosy patients with ocular disabilities (including those released from antileprosy treatment) should be targeted to receive eye care to prevent vision loss. Particular emphasis should be placed on young patients.

HIV and AIDS and the eye in developing countries: a review

An estimated 30 million people worldwide have been infected with the human immunodeficiency virus, the causative agent of the acquired immunodeficiency syndrome. Of these, 90% live in developing countries from where there is relatively little published information about the ocular manifestations of human immunodeficiency virus and acquired immunodeficiency syndrome. We review the information available from Africa, Latin America, and Asia. The prevailing ocular manifestations differ in some developing countries compared with those in the industrialized countries. These differences most likely result from different socioeconomic conditions and basic health care availability and from different patterns of endemic disease present before the human immunodeficiency virus epidemic.

Creation of priority criteria for corneal transplantation and analysis of factors associated with surgery following implementation

PURPOSE

We sought to test the effectiveness and application of a system for prioritizing corneal disease patients for corneal transplantation.

METHODS

All patients wait-listed for corneal transplantation in British Columbia in April 1995 were followed for 10 months to determine whether they received surgery and to assess the application of recently introduced priority criteria.

RESULTS

The factors that determined whether a patient had surgery were as follows: having vision in one eye only, being female, having progressive disease, and experiencing pain. The surgeon involved was also a factor. Overall, the priority system did not adequately predict who had surgery and who did not have surgery.

CONCLUSIONS

The priority system needs to be re-structured to reduce the contribution of months waited and to more adequately take into account patient need. Furthermore, its application by individual surgeons needs to be strengthened.

Correlation between the visual field indices and Heidelberg retina tomograph parameters

PURPOSE

We wished to determine whether a relationship exists between Heidelberg retina tomograph (HRT) parameters and the visual field indices.

METHODS

One eye was randomly chosen from 59 normal patients [normal visual field and normal optic nerve head (ONH) and intraocular pressure (IOP) < 21 mm Hg], 64 ocular hypertensive patients (normal visual field and normal OHN and IOP > 22 mm Hg), 124 high-tension glaucoma patients (abnormal visual field and/or abnormal optic nerve and IOP > 22 mm Hg) and 47 low-tension glaucoma patients (abnormal visual field and or optic disc and IOP < 21 mm Hg). All the patients were examined with Humphrey Perimeter, program 30-2, and HRT. Findings were assessed by analysis of variance, Pearson's correlation coefficient, and multiple linear regression.

RESULTS

Among all subjects, we noted a statistically significant correlation (Pearson's r, p < 0.001) between cup area, cup/disc area ratio, rim area, rim volume, cup shape measure, and retinal nerve fiber layer cross-section area with mean deviation and corrected pattern SD. Multiple linear regression analysis demonstrated that rim area was the most important predictor of mean deviation and corrected pattern SD.

CONCLUSIONS

The presence of significant correlations between some HRT parameters, such as rim area and cup shape measure and visual field indices, suggests that these HRT parameters could be good indicators of the degree of glaucomatous ONH damage.

Changing patterns of corneal disease and associated vision loss at a rural African hospital following a training programme for traditional healers

AIMS/BACKGROUND

Use of African traditional eye medicines (TEM) is associated with the presence of corneal disease, delay in presentation, and vision loss. An interactive training programme was conducted with traditional healers in Chikwawa District, Malawi and changes in the pattern of corneal disease assessed in patients presenting to the district hospital after the training.

METHODS

All patients presenting to the district hospital with corneal disease for a 15 month period before intervention and a 12 month period after intervention were enrolled in the study. Interviews and examinations were carried out by the same person using a standardised, pretested form.

RESULTS

Among the 175 pre-intervention and 97 post-intervention patients, delay in presentation improved only slightly. Blindness among patients reporting the use of TEM decreased from 44% to 21%; bilateral corneal disease in patients using TEM decreased from 31% to 10%. Multivariate analysis demonstrates that poor vision in corneal disease patients continues to be associated with TEM use and distance from the district hospital.

CONCLUSION

As there were no other relevant eye health programmes in the district it is believed that this collaborative eye care programme with the traditional healers was likely to have been responsible for many of the changes in the pattern of corneal disease in the district. Although the changing patterns are encouraging and are likely to improve with additional collaboration, distance to a district hospital will continue to be a barrier to timely use of Western eye care services.

Retinal findings predictive of outcome in cerebral malaria

The pathogenesis of cerebral malaria is poorly understood. Direct and indirect ophthalmoscope examinations of 141 Malawian children with strictly defined cerebral malaria revealed 2 distinct and prognostically significant findings: papilloedema and extramacular retinal oedema. The relative risk of death in patients with papilloedema was 6.7 times that in patients without papilloedema. Extramacular retinal oedema was associated with a 2.9 fold increase in the relative risk of dying. The mortality rate in patients with neither of these signs was only 1.3% compared to an overall mortality rate of 9.2%. The clinical and laboratory features associated with each of these ophthalmological findings were different, suggesting that there may be at least 2 different pathogenetic processes in patients with cerebral malaria.

A population-based survey of the prevalence of refractive error in Malawi

Refractive errors, particularly myopia, are a common problem in industrialized countries, but the impression exists that myopia may be relatively uncommon in non-industrialized societies. We conducted a population-based survey of refractive error in two groups of Malawians: a group of rural agricultural workers (n = 510) and a group of students at an urban teachers' college (n = 534). The overall prevalence of myopia was low; 2.5% (95% confidence interval 1.3%, 3.7%) of participants had an error of -0.5 D or greater. The mean refractive error (right eye) in the urban student group was +0.52 D compared to +0.62 D among the rural agricultural workers and the excess myopia was accounted for by significant myopia (> or = -0.75 D) in a few individuals, rather than an overall shift towards myopia within the urban student group. Among the rural agricultural workers, literacy predicted refractive error (right eye), with a mean of +0.59 D in the rural literate compared to +0.67 D in the rural illiterate. These findings support the notion that myopia is uncommon in non-industrialized societies and that it is associated with increased literacy but we have not identified specific risk factors within this group to predict the occurrence of significant myopia. In settings such as Malawi, refractive services should be targeted to urban centers, where more educated populations are likely to be found.

Eye care knowledge and practices among Malawian traditional healers and the development of collaborative blindness prevention programmes

Many African traditional healers provide treatment for eye diseases, yet there is little published information about eye care knowledge and practices among these healers; the information is necessary for the development of collaborative eye care activities with healers. Focus group discussions, in-depth interviews, and a representative sample survey of 107 randomly selected traditional healers in Chikwawa District, Malawi were conducted regarding eye care knowledge and practices. In the survey 68% of healers treated at least one of six common eye conditions. The most common eye condition treated by healers was cataract, followed by conjunctivitis/inflammatory trachoma. The size of the healer's practice, literacy, and great distance to a health facility were positively associated with the provision of eye care. Traditional healers have considerably more eye care interactions with the rural population than existing biomedical health personnel in Chikwawa District. Interviews revealed that most healers were aware of the availability of treatment for common eye conditions at biomedical health facilities and were interested in collaborating with existing biomedical eye care providers. We subsequently developed a collaborative eye care programme with healers in the district and report on early findings. Collaboration with healers in eye care programmes is advocated and recommendations are provided.

Corneal decompensation after cataract surgery. An outbreak investigation in Asia

PURPOSE

During 5 days in January 1994, two visiting expatriate ophthalmologists performed extracapsular cataract surgery on 111 patients at a nonprofit hospital in Asia. The authors investigated the development of postoperative corneal edema.

METHODS

An epidemiologic and clinical investigation was undertaken by a review of clinical charts, interview of personnel involved, an examination and interview of patients who underwent surgery, and a laboratory simulation of the disinfection procedure used.

RESULTS

Follow-up was available on 58% of the patients. The attack rate was at least 37% and likely to be approximately 64%. The attack rate was highest the first 2 days of surgery. Multivariate analysis showed that the day of surgery was the only characteristic significantly associated with the presence of corneal edema. A simulation of the disinfection technique used (soaked in 2% glutaraldehyde and rinsing) showed that significant levels of glutaraldehyde remain in instruments with small lumens after the rinse.

CONCLUSION

The epidemiologic data and simulation information are compatible; the lack of adequate rinsing of small lumen instruments soaked in glutaraldehyde is the most probable cause of this incident. Recommendations for surgeons on surgical expeditions are proposed.

Lagophthalmos in a multibacillary population under multidrug therapy in the People's Republic of China

Lagophthalmos may be the most common potentially blinding ocular condition in leprosy. The magnitude of the problem among multibacillary patients has not been determined. We sought to ascertain the magnitude of lagophthalmos in a multibacillary leprosy patient population under multidrug therapy (MDT) (both newly diagnosed and with a prior history of dapsone monotherapy) in China and assess factors associated with its presence. In a survey of 640 multibacillary patients 3.8% of the newly diagnosed patients and 10.2% of the patients with prior dapsone monotherapy had lagophthalmos. Corneal disease and vision loss were common in both groups. Poor compliance with MDT, duration between onset and diagnosis, and duration on dapsone monotherapy were associated with the presence of lagophthalmos. Our findings suggest that there may be a threshold at which MDT must be maintained to prevent lagophthalmos. Early leprosy diagnosis and treatment would also lessen the incidence of lagophthalmos in these patients. The high proportion of lagophthalmos patients with corneal disease suggests that there has been inadequate eye care for these patients.

The distribution of kwashiorkor in the southern region of Malawi

Using existing nutritional survey data collected over an 11-month period during the recent drought, we sought to determine the distribution of kwashiorkor in the ten districts of the Southern Region of Malawi. Sampling and survey methods were identical and considerable efforts were made to ensure comparability. In 23 surveys, 25,824 children were weighed and measured and oedema was recorded. The district-adjusted prevalence of kwashiorkor was 18/1000. The northernmost districts of the Southern Region had rates five to ten times higher than the southernmost districts. Prevalence peaked at 18-23 months and was similar in boys and girls. Dysentery was associated with the presence of kwashiorkor while diarrhoea was not. The distinctive pattern of kwashiorkor in the region suggests that there are characteristics specific to the northern districts that place children in these areas at greater risk of kwashiorkor.

Current concepts in the surgical management of lagophthalmos in leprosy

Existing data suggest that, at a minimum, 2% of paucibacillary patients and 5% of multibacillary patients have lagophthalmos; at least 290,000 people worldwide have leprosy-related lagophthalmos. Surgical intervention is the only method for correcting lagophthalmos; effectiveness of the different procedures commonly used has not been measured. Results from a survey of eye care providers revealed that surgeons in Asia used a wide range of different techniques for the correction of lagophthalmos while almost all of the surgeons in Africa used tarsorrhaphy. There is a need to evaluate surgical outcome of these techniques and to develop guidelines to assist in increasing the number of surgeries for lagophthalmos in leprosy patients.

Vitamin A capsule supplementation in Malawi villages: missed opportunities and possible interventions

A population-based survey was used to assess childhood and maternal vitamin A capsule coverage in Malawi and to investigate missed opportunities for capsule distribution. Overall, 9.3% of children had received vitamin A supplementation in the previous 6 months. Missed opportunities for receiving vitamin A were high in younger children. Fifty-five percent of mothers were covered in 8 villages served by volunteers and 23% in the 58 villages without volunteers. Existing strategies need to be redesigned and new strategies defined. For instance, mothers could receive supplementation during infant BCG vaccination, and children could receive initial supplementation during measles vaccination. Village health volunteers could be used to target children over 2 years of age.

Peripheral corneal ulcers associated with use of African traditional eye medicines

The most common cause of monocular blindness in Africa is corneal opacification. Traditional eye medicines (TEM) are widely used in Africa and their use has been associated with corneal ulceration, however, no controlled studies of the effects of TEM on the cornea have been published. We conducted a case-control study of 39 patients with corneal ulcers matched to controls with severe conjunctivitis. Microbiological investigations were conducted on 20 cases. There was a significant association between corneal ulceration and TEM use and, in particular, peripheral corneal ulcerations were significantly associated with TEM use.

A new focus of onchocerciasis in Mwanza District, Malawi

Anecdotal information suggested that a new focus of onchocerciasis had recently developed in Mwanza in Malawi, a district not contiguous with Thyolo, the only district in Malawi with recognized autochthonous transmission. We carried out a survey of the northern half of Mwanza district, randomly selecting 62 villages for assessment. Two iliac crest skin snips were taken from 2215 residents over the age of 15 years; one-quarter had Onchocerca volvulus microfilariae. Prevalence increased with age and was higher overall among men than women. The age-adjusted prevalence among migrants from Thyolo was 31%. Among residents who had never been outside Mwanza, the gender-specific prevalences and microfilarial loads were similar. The intensity of infection was low. Autochthonous transmission of O. volvulus has thus been demonstrated in Mwanza and illustrates the possibility of the spread of the disease to new foci in Malawi and the surrounding countries, due to significant population shifts.

Knowledge and attitudes toward onchocerciasis in the Thyolo highlands of Malawi

In preparation for mass distribution of ivermectin to control onchocerciasis in the Thyolo highlands of Malawi a survey was conducted to determine knowledge and attitudes toward onchocerciasis which could assist in developing educational messages. Since onchocerciasis is not known by a specific name in the Thyolo highlands, information was sought about individual perceptions of common symptoms of infection. Itching, skin thickening, nodules, or depigmentation (leopard skin) were reported by 95% of those interviews. Effective treatment was often thought by the community to be available when actually it was not. Traditional healers were not thought to be an important source for treatment of lesions associated with onchocerciasis. None of those interviewed associated Simulium damnosum s.l. with any symptoms other those related to the actual bite. Based on the information gathered, various options for ivermectin educational messages are discussed.

Acceptance of surgery for trichiasis among rural Malawian women

We sought to determine the proportion of women with trichiasis who subsequently accepted surgery and to evaluate factors related to acceptance. Women who accepted surgery were more likely to be widows, to be of low socioeconomic status, to live close to a main road, to know another woman who had surgery for trichiasis, and to have trichiasis in both eyes than women who did not accept surgery. Our results suggest that considerable education and encouragement are needed to increase acceptance of surgery for trichiasis.

Traditional eye medicine use among patients with corneal disease in rural Malawi

Over a 15 month period all patients with corneal ulcers presenting at two district hospitals were interviewed regarding demographic and clinical characteristics and their use of traditional eye medicines (TEM). Of the 583 patients interviewed, 33.8% reported using TEM. There were no age or sex differences in TEM use. Patients who reported TEM use took, on average, 51 days between onset of symptoms and presentation while patients who denied TEM use took 13 days. Sixteen per cent of TEM users had a vision in the affected eye of < 3/60 on presentation compared with 5% of non-TEM users. The frequent use of TEM and the presence of numerous traditional healers in rural areas of Africa suggest that eye care programmes could benefit greatly by including traditional healers in primary eye care activities.

Multidrug therapy and eye disease in leprosy: a cross-sectional study in the People's Republic of China

BACKGROUND

Factors associated with leprosy-related eye disease in a multidrug therapy (MDT) treated population in China were assessed to determine if status prior to inclusion in the MDT programme (newly diagnosed leprosy patient or leprosy patient on prior dapsone monotherapy) contributed to the prevalence of ocular pathology.

METHODS

Trained leprosy paramedical workers in Sichuan Province examined 974 leprosy patients in a standardized fashion. Univariate analyses and multiple logistic regression were used to assess the contribution of demographic and clinical parameters to leprosy-related eye disease.

RESULTS

In both groups (prior dapsone and new MDT) leprosy-related eye disease was associated with a longer distance to leprosy health worker or health centre. Among patients with a history of prior dapsone monotherapy, age and duration on dapsone monotherapy were also associated with leprosy-related ocular morbidity. Among newly diagnosed leprosy patients the prevalence of ocular morbidity remained between 8% and 11% regardless of when the patient started MDT.

CONCLUSIONS

Our findings suggest that, even when case detection is good, ocular pathology will still occur in MDT treated leprosy patients. There remains an important role for health workers in the prevention of ocular morbidity. Our data also demonstrated that pooling of results from all patients (newly diagnosed and on prior dapsone monotherapy) in a leprosy control programme will likely give rise to inadequate estimates of risk of ocular disease due to variable clinical disease histories in these groups.

Sociocultural aspects of blindness in an Egyptian delta hamlet: visual impairment vs. visual disability

Through ophthalmological exams, structured interviews and participant observation, this study examines the experience of blindness in rural Egypt, and finds that villagers' subjective assessments of their vision differ substantially from ophthalmic measurements of their vision. Individuals with profound visual loss remain independent in their daily activities and contribute to their families' subsistence. While they may agree that they have "weak eyesight," they do not perceive themselves to be disabled. Stigmatizing attitudes that the blind are completely dependent and unable to fulfill their social roles further encourage those with decreased vision to deny the extent of their visual loss.

Ocular fundus findings in Malawian children with cerebral malaria

BACKGROUND

Cerebral malaria is a major cause of mortality and morbidity in children in tropical regions. The pathogenesis of this important complication of Plasmodium falciparum infection is not well understood. A number of observers have commented on the presence of retinal pathology in various types of malaria. Previous reports have not demonstrated that fundus findings are significantly associated with outcome.

METHODS

The authors examined the ocular fundi, by direct and indirect ophthalmoscopy, of 56 children admitted consecutively with cerebral malaria.

RESULTS

Every child with a normal fundus on admission recovered fully, but two conditions were found to be associated with a poor outcome. Patients with papilledema had a relative risk of poor outcome 5.2 times greater than those without this finding (P < 0.01). Patients with retinal edema outside the posterior vascular arcades had a relative risk of poor outcome 3.9 times greater than those without this finding (P < 0.01). These two fundus findings were independently predictive of a poor outcome.

CONCLUSION

Fundus findings are useful as predictors of outcome in children with cerebral malaria. The authors' findings suggest that there may be two distinct mechanisms associated with poor outcome in these children.

Hydatid disease in the Hamar of Ethiopia: a public health problem for women

A population-based study of hydatid disease was conducted among the Hamar of Ethiopia. Seven of 990 patients examined with a portable ultrasound scanner proved to have cysts (0.7% prevalence). Cysts were most common (4.7%) among women > or = 40 years of age. Only one male presented with a cyst. These results indicate a sex-specific hydatid public health problem in this tribe.

The epidemiology of burns in rural Ethiopia

STUDY OBJECTIVE

The aims were (1) to review inpatient burn records of Attat Hospital (Ethiopia) for the years 1983-1989, and (2) to determine the prevalence of burns and knowledge of first aid for burns in 16 communities served by Attat Hospital in rural Ethiopia.

DESIGN

A retrospective review of all records was used to describe characteristics of the inpatient with burns and cost of the service. Adult members of a systematic random sample (20%) of households from 16 communities (total population = 10,183) were interviewed. Questions focused on what to do to put out the fire, what to do for first aid for a burn, the major cause of adult and childhood burns, and a history of burn in any household member.

SETTING

The study was conducted at Attat Hospital and in the surrounding Gurage-Chaha Region of West Shoa Province of Ethiopia.

STUDY SUBJECTS

There were 271 burn inpatients during the 7 year period from 1983-1989; 163 households were selected for interview; there were no refusals.

MAIN RESULTS

During the 7 year period the cost of tertiary inpatient burn treatment at Attat Hospital has been estimated to be US$86,366.72, of which the hospital absorbed 66%. From community based information the cumulative incidence of burns in this population was found to be 5-11%. The absence of a cumulative increase in burns over time in men suggests that female respondents may not fully recall burn histories in adult male household members. The study population possess inadequate knowledge regarding burn prevention and burn first aid. Deleterious traditional compounds were used on 32% of burn patients in the villages.

CONCLUSIONS

Since most burns are related to household fires, generally in the domain of women in rural Ethiopia, women's groups may be the most appropriate setting for education on burn prevention and first aid. Burn prevention and first aid education should also be recognised as a priority in schools and in the training of community health workers.

The epidemiology of blindness and visual loss in Hamar tribesmen of Ethiopia. The role of gender

We conducted a population-based survey in the Hamar tribe of Ethiopia to assess the problem of blindness and ocular morbidity. Blindness was detected in 1.9% of the Hamar. Among the age group 40 and over < 1.0% of men and 13% of women were blind. Women with low vision or blindness comprised 30% of all women while men with low vision or blindness only comprised 8% of men in the age stratum. Cataract is responsible for the excess blindness in women. Even mild visual disability is less common in men. In Hamar society men have two roles: as herders and as warriors. Warriors with visual loss will be less successful in defending themselves. We suggest that Hamar men who develop visual loss have increased mortality compared to women with visual loss. Vision loss in women does not appear to have life-threatening consequences. Cessation of hostilities between the Hamar and their neighbours could, conceivably, lead to an 'increase' in the incidence of vision loss among men.

Cell-mediated immunity in trachomatous scarring. Evidence from a leprosy population

BACKGROUND

There is limited understanding of the mechanisms that mediate immunity after infection by Chlamydia trachomatis. Since it is known that the clinical course of leprosy is related to cell-mediated immunity and that such immunity contributes to the development of trachomatous conjunctival scarring, the authors examined patients to determine if there might be an association between leprosy status and trachomatous conjunctival scarring.

METHODS

Leprosy patients registered at Shashemane Hospital were interviewed, examined, and patients with siblings residing in the vicinity were asked to return for further clinical examination. A subsample of sibships was selected for laboratory evaluation of cell-mediated immunity, measured by lymphocyte proliferative responses in vitro to stimulation by mycobacterial antigens.

RESULTS

Conjunctival scarring was less severe in multibacillary leprosy patients (with suppressed cell-mediated immunity) than in their healthy siblings and more severe in paucibacillary leprosy patients (with enhanced cell-mediated immunity) than in their healthy siblings. The mean lymphocyte proliferative responses to mycobacterial antigens were greater in the sibling (whether leprous or healthy) with more severe conjunctival scarring, regardless of type of leprosy.

CONCLUSION

The specific cellular immune responses to Mycobacterium leprae and p65 antigen in patients with increased conjunctival scarring provide evidence that early in the course of infection with C. trachomatis, factors related to an individual's cellular response are crucial to the development of conjunctival scarring. A delayed-type hypersensitivity reaction ("reversal reaction") found in paucibacillary leprosy patients could contribute to the increased trachomatous conjunctival scarring in these patients.

Considerations in the integration of eye care into leprosy care services

Little attention has been directed to the development, management and evaluation of eye care programmes for leprosy patients. This paper examines when an eye care programme for leprosy patients is needed, methods for integrating eye care into leprosy control programmes and lists of available ocular leprosy teaching materials.

Anatomical factors influencing development of trichiasis and entropion in trachoma

There has been no published investigation into the reasons why some patients with severe trachomatous conjunctival scarring develop entropion and trichiasis while others do not. In a population of leprosy patients with severe trachomatous conjunctival scarring the authors found that lagophthalmos correlated with the absence of trichiasis and entropion. We suggest that orbicularis oculi muscle function, as well as other anatomical variations among individuals, may contribute to the development of trachomatous entropion and trichiasis in patients with conjunctival scarring.

Comparison of the old and new W.H.O. leprosy disability grading scheme for ocular disabilities

We compared the old (1970) and new (1988) World Health Organization schemes for classifying the ocular disabilities in leprosy patients. 509 leprosy patients from eight resettlement villages in central South Korea were examined and graded by eye according to both of the schemes. A more liberal definition of severely disabled in 1988 resulted in a 119% increase in eyes graded as severely disabled in this population. 59 eyes were graded as severely disabled by the old scheme and 129 eyes were so graded according to the new scheme. Keratitis, one of three measures of moderate disability in the old scheme, was replaced by corneal anaesthesia in the new scheme, but this change did not make a substantial difference in the number of patients in the moderately impaired category. In the absence of longitudinal studies documenting the significance of keratitis, it is unclear whether the change in an improvement. The new disability scheme improved upon the old by removing the criteria for mild impairment.

Latrine ownership as a protective factor in inflammatory trachoma in Egypt

We investigated the association between inflammatory trachoma in children aged 1-5 and environmental and sociodemographic risk factors in a rural Nile Delta hamlet. Inflammatory trachoma clustered in households, emphasising the child-to-child nature of transmission in the hamlet. Multiple logistic regression analysis revealed three factors predicting inflammatory trachoma in children: the absence of a latrine in the household, school-age siblings with inflammatory trachoma, and additional same-age siblings (with or without disease) in the household. In the Egyptian setting the presence of pit latrines in all houses, even when full and unscreened, might result in a reduction in trachoma prevalence in this population from the current 49% to 35%. The construction of pit latrines may offer the simplest and most acceptable environmental method for reducing trachoma in this trachoma endemic area.

Intraocular pressure and iris denervation in Hansen's disease

We retrospectively analyzed 255 Hansen's disease patients and found low intraocular pressure (less than 7 mm Hg) in 12% of them. We showed a correlation between low intraocular pressure and avascular keratitis and iritis. We also found that patients with low intraocular pressures had abnormally large postural changes in intraocular pressure. We speculate that abnormalities in the autonomic innervation of the anterior segment of the eye may be related to the intraocular pressure abnormalities. Further investigations along this line may increase our understanding not only of the pathophysiology of Hansen's disease but also of the mechanisms regulating homeostasis of intraocular pressure.

Problems with current concepts of the epidemiology of Mooren's corneal ulcer

Results from an analysis of 287 patients in 20 series do not support widely held concepts of the descriptive epidemiology of Mooren's corneal ulcer, i.e., that bilateral disease is more common in younger patients and blacks. Our review shows that the disease is reported 1.6 times more frequently in males than in females regardless of race or age. Black patients are five times more likely to be young than are white patients. However these figures may be misleading since they are not calculated from population-based estimates. Our analysis highlights misconceptions and emphasizes the hazards of drawing conclusions about the epidemiologic characteristics of this disease based on currently available data.

Training for primary eye care in leprosy

Reported are the results of a primary eye care training programme for community-based leprosy control workers in the Republic of Korea. The 20-hour programme emphasized the detection and management of lagophthalmos (and its complications) and chronic iridocyclitis. Leprosy patients in four resettlement villages were examined independently by the health workers and an ophthalmologist. Agreement between the health workers and the ophthalmologist was good for the detection of most signs (lagophthalmos, acute iridocyclitis, and chronic iridocyclitis). Based on these preliminary results it is recommended that primary eye care be included as a part of the training for leprosy paramedical workers.

Epidemic keratoconjunctivitis in a university medical center ophthalmology clinic; need for re-evaluation of the design and disinfection of instruments

During the period from early December 1987 to late January 1988, an outbreak of epidemic keratoconjunctivitis (EKC) caused by adenovirus type 8 occurred at a university medical center eye clinic. A telephone survey of patients revealed an attack rate of 17% among patients seen during the epidemic period. A case-control study demonstrated that development of EKC was associated with exposure to pneumotonometry and to three caregivers. After controlling for exposure to pneumotonometry, however, only exposure to one caregiver was significantly associated with risk of the disease. On January 19, 1988, after recognition of the outbreak, the eye clinic instituted additional infection control measures. A survey of patients seen the following week showed a substantial decrease in the attack rate (1.9%). Before these control measures were implemented, clinic personnel had followed the manufacturer's recommendations and disinfected pneumotonometer tips with 70% isopropyl alcohol, fearing that other disinfectants would corrode the instrument metal. Isopropyl alcohol, shown to have limited activity against adenovirus in vitro, also was being used to "disinfect" pneumotonometer tips between uses at six other area eye clinics polled by telephone. The results of this study demonstrate the need for changes in the design and manufacture of equipment used in the eye clinic.

Ocular autonomic dysfunction and intraocular pressure in leprosy

We examined 241 leprosy patients and 135 age-matched healthy controls in central South Korea, measuring intraocular pressure in the supine and the upright positions and measuring the size of the pupils in darkness as an indication of ocular autonomic dysfunction. The mean intraocular pressure was significantly lower in the patients and the mean size of pupils was significantly smaller in the patients than in the controls. However, there was no correlation between pupil size and intraocular pressure in our patients. Our findings show that leprosy patients have ocular autonomic dysfunction, but do not support previous speculation that this dysfunction is the primary cause for low intraocular pressure in leprosy.

Low intraocular pressure and postural changes in intraocular pressure in patients with Hansen's disease

We found intraocular pressures of less than 7 mm Hg in 11 of 72 patients (15%) with early Hansen's disease. Furthermore, significant postural changes in intraocular pressure (greater than 30%) occurred in 43 of 72 patients (60%). This loss of intraocular pressure homeostasis, which results from reduced aqueous humor production or increased uveoscleral outflow with reduced local adrenergic control in the ciliary body-iris-trabecular meshwork region, suggests that early autonomic neuropathy of the eye may occur in Hansen's disease. The only predictive value for significant postural change in intraocular pressure was the presence of immunologically unstable disease.

Trachoma and blindness in the Nile Delta: current patterns and projections for the future in the rural Egyptian population

A population based survey of trachoma and blindness was conducted in a rural Nile Delta hamlet. Trachoma remains hyperendemic in this region. Active trachoma was common among preschool children; over half had moderate to severe disease. Of residents 25 years old 90% had substantial conjunctival scarring. Severe conjunctival scarring was commoner among women (84%) than men (58%), and three-quarters of older women had trichiasis/entropion compared with 57% of older men. Males and females had equivalent age specific rates of inflammatory disease. Blindness was associated with old age; 17% of residents aged 50 and over were blind. Estimates of blindness based on this survey and other surveys in Egypt indicate that blindness is still a serious public health problem in rural Egypt. The number of blind persons in Egypt will increase from an estimated 420,000 in 1980 to 868,000 by the year 2020. The current crude blindness rate of 1.8% is expected to increase to 2.3% in the year 2000 and to 3.2% in 2020.

Use of a Chlamydia trachomatis DNA probe for detection of ocular chlamydiae

We examined the efficacy of a Chlamydia trachomatis DNA probe in detecting ocular chlamydiae by comparing it with tissue culture isolation, direct fluorescent-antibody cytology, and clinical eye exams. In a trachoma-endemic area of Nepal, 430 Nepalese villagers were examined according to the World Health Organization trachoma grading scale. Upper tarsal conjunctival specimens from each subject were obtained for DNA probing, tissue culture, and fluorescent-antibody screening. Moderate to severe intensity of inflammation was found in 85 (21%) of 430 people studied. An additional 25 (7.2%) of 345 people with low or no intensity of inflammation also had microbiologically proven infection, which may reflect asymptomatic carriage. Compared with culture, the DNA probe had a sensitivity of 86.9% and a specificity of 91%. For direct fluorescent antibody versus culture, the values were 47.8 and 96.9%, respectively. Results from this study indicate that the DNA probe for C. trachomatis might be considered a valuable epidemiologic tool in screening trachoma-endemic populations for ocular chlamydiae.

Nonculture methods for diagnosing chlamydial infection in patients with trachoma: a clue to the pathogenesis of the disease?

We studied five different tests for diagnosing conjunctival Chlamydia trachomatis infection in specimens obtained from 100 children with moderate-to-severe trachoma. The tests were Giemsa stain, isolation in cell culture, direct fluorescein-conjugated monoclonal antibody, enzyme immunoassay, and a DNA probe. The Giemsa stain was least sensitive at 29%. The other tests gave essentially equivalent performances: sensitivity ranged from 73% to 84% and specificity from 93% to 100%. Seven of the 45 positive specimens were only positive in cell culture, whereas 11 of the 45 were negative in culture but positive in at least two nonculture tests. We speculate that these discordant results actually reflect the biologic status of the chlamydial infection. There appears to be a stage in the infection where chlamydial antigens and nucleic acids can be detected in the absence of infectivity. This stage of infection may contribute to the pathogenesis of trachoma by providing a source of sensitizing antigen.