Navigating diagnostic and therapeutic challenges in ocular manifestations of Hansen's disease and trachoma: A narrative review.

Neglected tropical diseases (NTDs) encompass a group of approximately 20 diseases prevalent in tropical and subtropical regions, closely associated with poverty, affecting over a billion people in low-income countries. This manuscript aims to explore the ocular manifestations and burden of two significant NTDs, namely Hansen's disease and trachoma while addressing gaps in understanding and management. Hansen's disease, caused by Mycobacterium leprae , has a long history and presents with diverse neurological and ocular manifestations. Despite the availability of treatment, ocular complications persist, leading to significant visual impairment in some cases. The manuscript emphasizes the importance of early diagnosis, regular ophthalmic examinations, and follow-ups to prevent and control ocular complications, reducing the burden of visual impairment and blindness. Trachoma, caused by Chlamydia trachomatis , remains the leading infectious cause of blindness in underdeveloped and remote areas. The manuscript highlights the clinical diagnosis and implementation of the World Health Organization's (WHO's) SAFE (surgery, antibiotics, facial hygiene, and environmental sanitation) strategy to prevent transmission and associated blindness. However, challenges in health surveillance tools and underreporting of trachoma cases are addressed, emphasizing the need for improved strategies to combat the disease effectively. Through a comprehensive review of the ocular manifestations and management of Hansen's disease and trachoma, this manuscript contributes to the existing knowledge base and enhances a deeper understanding of these NTDs. Addressing gaps in understanding and management emphasizes the importance of implementing WHO's strategies and collaborative efforts to achieve the global goal of reducing the burden of NTDs and improving community health and well-being. The manuscript underscores the significance of early intervention, preventive measures, and technological advancements, providing valuable insights for policymakers, healthcare professionals, and researchers working in the field of NTDs.

Corneal blindness in Plato's cave: the acting forces to prevent and revert corneal opacity. Part I: epidemiology and new physiopathological concepts.

The burden of corneal blindness and visual deficiency can be felt worldwide. Its association with several endemic diseases such as childhood blindness, trauma, infectious keratitis (including variants caused by herpes, hanseniasis, and fungi), vitamin A deficiency, diabetes mellitus, and other dry eye syndromes reflects its poorly understood underlying mechanisms and suggests that the actual frequency of the disease is underestimated. The low effectiveness of preventive and therapeutic strategies against corneal scarring or deformity predicts a high frequency of patients with corneal blindness in the future. Corneal blindness is associated with environmental factors and socioeconomic limitations that restrain health assistance and maintain a modest efficiency of the current therapeutic strategies for resolving corneal diseases in large-scale programs. We present here a critical review of the concepts associated with corneal blindness that need to be considered when planning strategies to prevent and treat corneal blindness worldwide (to be able to leave Plato's cave, where corneal blindness is encaged.

Corneal blindness in Platos cave: the acting forces to prevent and revert corneal opacity. Part I: epidemiology and new physiopathological concepts / A cegueira corneal na caverna de Platão: as forças para prevenir e reverter a opacidade da córnea. Parte I: epidemiologia e novos conceitos na fisiopatologia

ABSTRACT The burden of corneal blindness and visual deficiency can be felt worldwide. Its association with several endemic diseases such as childhood blindness, trauma, infectious keratitis (including variants caused by herpes, hanseniasis, and fungi), vitamin A deficiency, diabetes mellitus, and other dry eye syndromes reflects its poorly understood underlying mechanisms and suggests that the actual frequency of the disease is underestimated. The low effectiveness of preventive and therapeutic strategies against corneal scarring or deformity predicts a high frequency of patients with corneal blindness in the future. Corneal blindness is associated with environmental factors and socioeconomic limitations that restrain health assistance and maintain a modest efficiency of the current therapeutic strategies for resolving corneal diseases in large-scale programs. We present here a critical review of the concepts associated with corneal blindness that need to be considered when planning strategies to prevent and treat corneal blindness worldwide (to be able to leave Plato's cave, where corneal blindness is encaged.

RESUMO O problema da deficiência visual e da cegueira corneal abrange o mundo todo e corresponde à quarta causa de cegueira e deficiência visual, com acometimento estimado de mais de 16 milhões de pessoas. A associação com várias doenças endêmicas, como cegueira infantil, trauma, ceratites infecciosas (incluindo herpes, hanseníase e fungos), hipovitaminose A, diabetes mellitus e outras causas de síndromes de olho seco, indicam que a verdadeira frequência é subestimada e que os diferentes mecanismos são pouco conhecidos. A baixa eficácia na prevenção e tratamento da cicatriz e deformidade da córnea permite antecipar que a prevalência da cegueira corneal irá crescer no futuro. As razões para o aumento da cegueira corneal envolvem fatores ambientais, limitações socioeconômicas para ampliar a assistência à saúde e a modesta eficiência das estratégias terapêuticas para resolver o problema em grande escala. O presente trabalho traz uma revisão crítica dos conceitos associados à cegueira corneal. Essa análise é uma etapa necessária para preparar o caminho com o objetivo de deixar a caverna que encarcera a cegueira corneal, em analogia ao mito de Platão, e melhorar as estratégias para prevenir e tratar a cegueira corneal em escala mundial.

Unsolved matters in leprosy: a descriptive review and call for further research.

Leprosy, a chronic mycobacterial infection caused by Mycobacterium leprae, is an infectious disease that has ravaged human societies throughout millennia. This ancestral pathogen causes disfiguring cutaneous lesions, peripheral nerve injury, ostearticular deformity, limb loss and dysfunction, blindness and stigma. Despite ongoing efforts in interrupting leprosy transmission, large numbers of new cases are persistently identified in many endemic areas. Moreover, at the time of diagnosis, most newly identified cases have considerable neurologic disability. Many challenges remain in our understanding of the epidemiology of leprosy including: (a) the precise mode and route of transmission; (b) the socioeconomic, environmental, and behavioral factors that promote its transmission; and

Ocular leprosy.

Ocular involvement in leprosy is estimated to be 70-75%, about 10-50% of leprosy patients suffer from severe ocular symptoms, and blindness occurs in about 5% of patients. The disease leads to many ophthalmologic symptoms and signs in the range of the eyeball itself, as well as of the bulb adnexa, ie, eyebrows, eyelids with eyelashes, and lacrimal drainage system. Especially dangerous are complications of lagophthalmos and corneal hypoanesthesia, neurotrophic or infectious keratitis, and iridocyclitis and cataract formation, which may lead to significant decrease of visual acuity or even blindness. Multidrug treatment rapidly interrupts transmission of Mycobacterium leprae by infectious patients, but even after being completed, it does not guarantee the withholding of ocular complications.

Ocular leprosy

Ocular involvement in leprosy is estimated to be 70-75%, about 10-50% of leprosy patients suffer from severe ocular symptoms, and blindness occurs in about 5% of patients. The disease leads to many ophthalmologic symptoms and signs in the range of the eyeball itself, as well as of the bulb adnexa, ie, eyebrows, eyelids with eyelashes, and lacrimal drainage system. Especially dangerous are complications of lagophthalmos and corneal hypoanesthesia, neurotrophic or infectious keratitis, and iridocyclitis and cataract formation, which may lead to significant decrease of visual acuity or even blindness. Multidrug treatment rapidly interrupts transmission of Mycobacterium leprae by infectious patients, but even after being completed, it does not guarantee the withholding of ocular complications.

[Ocular leprosy: a historical approach]. / Hanseníase ocular: uma abordagem histórica.

A sharp drop in the prevalence of leprosy occurred in the last three decades. However, the incidence has not decreased at the same rate. Three years after the World Health Organization last deadline for leprosy control, patients considered healed still need special care for their incapacities and immunopathological reactions. Medical literature reffers blindness in 4% to 11% of studied patients and more than 20% with severe visual problems due to corneal exposure, bacillary invasion and hipersensibility. These mechanisms result in a population of nearly one million blind leprosy patients even though official prevalence accounts no more than 250,000 patients worldwide. The author calls for better patients management and follow-up and urges ophthalmologists to become more aware and interested in the treatment of the ocular complications of leprosy.

Hanseníase ocular: uma abordagem histórica / Ocular leprosy: a historical approach

Houve uma acentuada queda na prevalência da hanseníase nas últimas três décadas. Contudo, a incidência não diminuiu na mesma proporção. Hoje, três anos após a última data estipulada pela Organização Mundial da Saúde para o controle da hanseníase, pacientes considerados curados ainda necessitam de cuidados especiais por causa de suas incapacidades e reações imunológicas. A literatura médica refere cegueira em 4 por cento a 11 por cento dos pacientes estudados e, mais de 20 por cento com graves problemas visuais devido a exposição da córnea, invasão bacilar e hipersensibilidade; estes mecanismos resultam em uma população de aproximadamente 1 milhão de pacientes cegos, embora a prevalência oficial não passe de 250.000 pacientes em todo o mundo. O autor destaca a necessidade de melhor tratamento e acompanhamento dos pacientes e, conclama os oftalmologistas a tornarem-se mais perceptivos e se interessarem mais pelo tratamento das complicações oculares da hanseníase.

A sharp drop in the prevalence of leprosy occurred in the last three decades. However, the incidence has not decreased at the same rate. Three years after the World Health Organization last deadline for leprosy control, patients considered healed still need special care for their incapacities and immunopathological reactions. Medical literature reffers blindness in 4 percent to 11 percent of studied patients and more than 20 percent with severe visual problems due to corneal exposure, bacillary invasion and hipersensibility. These mechanisms result in a population of nearly one million blind leprosy patients even though official prevalence accounts no more than 250,000 patients worldwide. The author calls for better patients management and follow-up and urges ophthalmologists to become more aware and interested in the treatment of the ocular complications of leprosy.

Ocular manifestation in treated multibacillary Hansen's disease.

PURPOSE: To report the prevalence of ocular morbidity in patients with treated multibacillary Hansen's disease (HD) using modern ophthalmic diagnostic techniques in a rural community endemic for HD. DESIGN: Cross-sectional, observation study. PARTICIPANTS: All patients with multibacillary HD who had completed their multidrug therapy and who resided in 4 defined geographical areas in Vellore, Tamil Nadu, India. METHODS: All participants underwent a complete eye examination that included slit-lamp examination, esthesiometry, gonioscopy, applanation tonometry, and dilated fundus examination, including a stereobiomicroscopic examination of the fundus at an ophthalmic center set up for that purpose. Glaucoma suspects underwent automated perimetry using a Humphrey Field Analyzer (Humphrey Instruments, San Leandro, CA). MAIN OUTCOME MEASURES: The prevalence of various ocular disease parameters were reported as mean value with 95% confidence interval. The difference of disease prevalence between various leprosy groups was compared using an unpaired t test. The association between eye symptoms and potentially sight-threatening complications was analyzed using the chi-square test. RESULTS: Three hundred eighty-six of the 446 patients with multibacillary HD residing in the defined areas were evaluated. Four patients (1.04%; 95% confidence interval [CI], 0.0%-2.0%) were bilaterally blind; 33 (8.55%; 95% CI, 5.8%-11.3%) had unilateral blindness. Mean intraocular pressure was 12 mmHg (standard deviation, 4.1 mmHg), and prevalence of glaucoma was 3.6% (95% CI, 1.8%-5.5%). Potentially sight-threatening (PST) pathologic features (corneal anesthesia, lagophthalmos, uveitis, scleritis, and advanced glaucoma) were present in 10.4% (95% CI, 7.4%-13.4%) of patients. Significant cataracts occurred 3 times more frequently in those with polar lepromatous leprosy. The odds ratio for PST pathology in the presence of patient-reported symptoms (pain, redness, inability to close eye, burning, and irritation) was 2.9 (95% CI, 1.34-6.26). CONCLUSIONS: Patients who have completed treatment for multibacillary HD continue to have significant ocular morbidity. A history of specific eye symptoms can be the basis for referral by field staff.

Leprosy blindness in Nepal.

Leprosy is a systemic disease with highest incidence of ocular complications and one of the important causes of blindness in the world. A comparative cross-sectional study was carried out to see the ocular involvement in leprosy leading to blindness in two groups of patients, one with the active disease and second already cured and thus released from treatment (RFT). Active cases attending Anandaban leprosy clinic, Patan hospital and RFT cases from Khokana leprosarium were included in the study consecutively. Total of 70 active cases and 101 RFT cases were evaluated during the study period. Active group of patients showed more of multibacillary type of disease than in RFT group. The prevalence of ocular manifestations was seen much higher among RFT cases accounting for 66.3% in contrast to active group where only 14.3% had ocular problems. Blindness was frequently seen in multibacillary (MB) leprosy patients in compare to paucibacillary (PB) disease in both the groups. However blindness frequency was seen more often among RFT cases accounting for 24% in compare to only 2.9% among active group. Causes of blindness were mainly corneal and cataract related disorders. Risk of blindness also increased with the increase in duration of illness. RFT group of leprosy patients are at higher risk of developing blindness than the active group thus eye care services should be more focused for this group. Having multibacillary type of disease could also be a risk for development of blindness.

Patterns of ocular morbidity and blindness in leprosy--a three centre study in Eastern India.

BACKGROUND: Eye disease and visual impairment due to leprosy are not uncommon, but their prevalence and the risk factors for such pathology have yet to be fully characterized. METHODS: An observational study of leprosy-affected individuals in the community, in three districts in Eastern India was performed to determine the prevalence of ocular morbidity and blindness. The subjects were chosen by stratified random sampling, according to stage of treatment, or stage of post-treatment surveillance. Each subject underwent ophthalmic examination according to a standard pro-forma. RESULTS: Thirty-three out of 1137 (2.9%) subjects were blind according to the WHO classification, and 232/1137 (20.7%) had moderate visual impairment. The prevalence of blindness and visual impairment was greatest in one centre, Jhalda. Multivariate Logistic Regression analysis showed that longer duration of disease, more advanced treatment stage and older age were independently associated with blindness. One hundred and forty-one cases (28%) in Muzaffarpur, 95 cases (63%) in Saldoha and 378 cases (78%) in Jhalda had active or treated multibacillary leprosy. DISCUSSION: The prevalence of blindness in leprosy varies in different population groups, with differing patterns of leprosy-related ocular morbidity, blindness and disease type evident even in different areas of the same region. Leprosy screening and surveillance programmes should include ocular examination as part of routine screening, particularly in individuals with a history of multi-bacillary disease. Individuals with known sight- threatening pathology should undergo continued active follow up. Local epidemiological studies would enable appropriate programme planning and efficient allocation of resources.

Ocular leprosy in Nigeria: a survey of an Eku leprosorium.

To determine the ocular morbidity, visual disability and potential for blindness in leprosy patients recently released from treatment. In-patients from Eku leprosy settlement were interviewed and examined for ocular disease from leprosy and other causes. They were examined using the Snellen's chart, pentorch, Kowa portable slit-lamp, direct ophthalmoscope and the pulsair non-contact tonometer. The patients were also refracted. In all, 60 inpatients who were recently released from treatment, comprising 39 men (65%) and 21 women (35%), were examined. Fifty-eight patients (96.67%) had ocular symptoms, the most common being blurred vision in 23 patients (38.33%). Nine patients (15%) were blind. Cataract was the most common cause of blindness occurring in three of the nine patients (33.33%). The most common types of ocular lesions were madarosis (31.67%), lagophthalmos (16.67%) and cataract (16.67%). Potentially blinding conditions due to leprosy were seen in 42 patients (70%). The incidence of ocular involvement, blindness and potentially blinding conditions are high in leprosy patients recently released from treatment. Regular ophthalmic evaluation and integration into Vision 2020 programmes are recommended.

Prevalence and causes of blindness and low vision in leprosy villages of north eastern Nigeria.

AIMS: To determine the prevalence and spectrum of ocular pathology, and the prevalence and causes of blindness and low vision in leprosy villages of north eastern Nigeria. METHODS: People affected by leprosy, aged 30 years and above, resident in eight leprosy villages were invited to participate. Ocular examination was undertaken of each consenting individual. RESULTS: 480 people were examined. 456 (48%) of 960 eyes had at least one ocular lesion, but only 37% of all lesions were leprosy related and potentially sight threatening. The prevalence of blindness (VA<3/60 with available correction) was 10.4%. An additional 7.5% of subjects were severely visually impaired (3/60< or =VA<6/60). Cataract was the commonest cause of blindness. Other major causes were non-trachomatous corneal opacity and trachoma. CONCLUSIONS: Blindness and low vision are highly prevalent among leprosy patients in this setting. Only a third of the burden of ocular pathology is related to the direct effects of leprosy. Efforts to reduce the backlog of cataract and trichiasis, to improve early detection and management of lagophthalmos, and to provide refractive services are urgently required.

Factors associated with sight threatening lesions of leprosy in patients on multidrug therapy.

One hundred and six consecutive patients (old and newly diagnosed) attending the leprosy clinic at Guru Teg Bahadur Hospital, Delhi, underwent a detailed ophthalmic examination to identify factors associated with the prevalence of sight threatening lesions of leprosy so as to delineate a sub-group of patients who should continue under active ophthalmic surveillance to prevent blindness. All of them were receiving multidrug therapy as recommended by WHO. Demographic data, systemic parameters and ophthalmic lesions attributable to the disease were endorsed on to a proforma. The data were analysed by chi-square test, discriminant analysis and multivariate regression analysis to isolate factors that could be associated with sight threatening lesions of leprosy. In 106 leprosy patients 212 eyes were examined; sight threatening lesions were found in 37 eyes (17.4%). The comea was involved most commonly (78.3%). The lesions were still present in 15.8% of patients who had completed multidrug therapy. Leprosy related visual impairment was seen in 2.3% eyes and blindness in 0.9% eyes. Factors significantly associated with sight threatening lesions included female gender, multibacillary leprosy, increasing duration of leprosy, thickened corneal nerves, subepithelial punctate corneal opacities and presence of any academic lesion of leprosy. On multivariate and discriminant analysis, female gender, thickened corneal nerves and duration of leprosy > 7 years were significantly associated with sight threatening lesions.

A survey of blindness and poor vision in leprosy patients.

OBJECTIVE: To determine the prevalence, cause and distributions of blindness and poor vision in patients with leprosy. METHODS: An epidemiological survey of blindness and poor vision among 1045 cases of leprosy was carried out in Taixing City of Jiangsu Province, China. RESULTS: The prevalence of bilateral blindness was 7.67%, unilateral blindness 4.4%, bilateral poor vision of various degrees 9.28% and unilateral poor vision 5.84%. The prevalence of eye complications varied significantly among different groups of patients; females had a higher prevalence than males, multibacillary patients higher than paucibacillary patients, and in-patients higher than out-patients. Corneal disease was the most common cause of blindness in study groups, followed by iritic disease and cataract; while the main cause of poor vision was cataract, then corneal and iritic diseases. Treatable blindness accounted for 62.7% of the cases and treatable poor vision for 88.6% of the patients studied. 56.62% of cases with eye complications expressed their willingness to be treated. CONCLUSIONS: Although prevention and treatment of low vision and blindness in leprosy patients is very hard, it is necessary for doctors and medical workers to make clear of the factors to cause low vision and blindness, especially those in leprosy patients so that some measures for prevention and treatment of the disease could be taken accordingly.

Blindness in Africa: present situation and future needs.

AIM: To review the prevalence and causes of blindness in sub-Saharan Africa, the existing services and limitations, and the Vision 2020 goals for the future. METHODS: Methodologically sound population based surveys published in the past 20 years are reviewed and results for prevalence and causes of blindness are tabulated. The current resources and needs according to recent publications and international working groups are described. CONCLUSIONS: Blindness prevalence rates vary widely but the evidence suggests that approximately 1% of Africans are blind. The major cause is cataract; trachoma and glaucoma are also important causes of blindness. The bulk of blindness in the region is preventable or curable. Efforts should focus on eye problems which are universally present and for which there are cost effective remedies, such as cataract and refractive problems and on those problems which occur focally and can be prevented by primary healthcare measures, such as trachoma, onchocerciasis, and vitamin A deficiency. Major development of staffing levels, infrastructure, and community programmes will be necessary to achieve Vision 2020 goals.

Corneal blindness: a global perspective.

Diseases affecting the cornea are a major cause of blindness worldwide, second only to cataract in overall importance. The epidemiology of corneal blindness is complicated and encompasses a wide variety of infectious and inflammatory eye diseses that cause corneal scarring, which ultimately leads to functional blindness. In addition, the prevalence of corneal disease varies from country to country and even from one population to another. While cataract is responsible for nearly 20 million of the 45 million blind people in the world, the next major cause is trachoma which blinds 4.9 million individuals, mainly as a result of corneal scarring and vascularization. Ocular trauma and corneal ulceration are significant causes of corneal blindness that are often underreported but may be responsible for 1.5-2.0 million new cases of monocular blindness every year. Causes of childhood blindness (about 1.5 million worldwide with 5 million visually disabled) include xerophthalmia (350,000 cases annually), ophthalmia neonatorum, and less frequently seen ocular diseases such as herpes simplex virus infections and vernal keratoconjunctivitis. Even though the control of onchocerciasis and leprosy are public health success stories, these diseases are still significant causes of blindness--affecting a quarter of a million individuals each. Traditional eye medicines have also been implicated as a major risk factor in the current epidemic of corneal ulceration in developing countries. Because of the difficulty of treating corneal blindness once it has occurred, public health prevention programmes are the most cost-effective means of decreasing the global burden of corneal blindness.