RESUMO
Trachoma is initiated during childhood following repeated conjunctival infection with Chlamydia trachomatis, which causes a chronic inflammatory response in some individuals that leads to scarring and in-turning of the eyelids in later life. There is currently no treatment to halt the progression of scarring trachoma due to an incomplete understanding of disease pathogenesis. A cohort study was performed in northern Tanzania in 616 children aged 6 to 10 years at enrollment. Every 3 months for 4 years, children were examined for clinical signs of trachoma, and conjunctival swabs were collected for C. trachomatis detection and to analyze the expression of 46 immunofibrogenic genes. Data were analyzed in relation to progressive scarring status between baseline and the final time point. Genes that were significantly associated with scarring progression included those encoding proinflammatory chemokines (CXCL5, CCL20, CXCL13, and CCL18), cytokines (IL23A, IL19, and IL1B), matrix modifiers (MMP12 and SPARCL1), immune regulators (IDO1, SOCS3, and IL10), and a proinflammatory antimicrobial peptide (S100A7). In response to C. trachomatis infection, IL23A and PDGF were significantly upregulated in scarring progressors relative to in nonprogressors. Our findings highlight the importance of innate proinflammatory signals from the epithelium and implicate interleukin 23A (IL-23A)-responsive cells in driving trachomatous scarring, with potential key mechanistic roles for PDGFB, MMP12, and SPARCL1 in orchestrating fibrosis.
Assuntos
Cicatriz/patologia , Cicatriz/fisiopatologia , Túnica Conjuntiva/patologia , Imunidade Inata , Fatores Imunológicos/biossíntese , Tracoma/patologia , Tracoma/fisiopatologia , Criança , Chlamydia trachomatis/crescimento & desenvolvimento , Feminino , Perfilação da Expressão Gênica , Humanos , Fatores Imunológicos/genética , Estudos Longitudinais , Masculino , TanzâniaRESUMO
IMPORTANCE: In vivo confocal microscopy (IVCM) provides high-resolution images of the ocular surface and has been validated in trachomatous conjunctival scarring. BACKGROUND: This study used IVCM to identify parameters associated with clinical scarring progression. DESIGN: Prospective cohort study. PARTICIPANTS: A total of 800 participants in Northern Tanzania with trachomatous scarring. METHODS: Participants underwent clinical examination, photography and IVCM at baseline and 24-months. Clinical progression of scarring was defined by comparing baseline and 24-month photographs. Masked grading of IVCM images was used to identify scarring at both time points. Multivariable logistic regression was used to assess factors associated with clinical progression. MAIN OUTCOME MEASURES: Risk factors associated with clinical scarring progression. RESULTS: Clinical and IVCM assessment of 800 participants were performed at baseline, with 617 (77.1%) seen at 24-months. Of these, 438 of 617 (71.0%) had gradable IVCM images at both time points and 342 of 438 (78.1%) of these could be graded as showing definite clinical progression or no progression on image comparison. Clinical progression was found to occur in 79 of 342 (23.1%). After adjusting for age and sex, clinical scarring progression was strongly associated with a high IVCM connective tissue organization score at both baseline (odds ratio [OR] = 1.84 for each increase in scarring category; P = .002) and 24-months (OR = 1.60; P = .02). Dendritiform cells present at 24-months were strongly associated with clinical scarring progression after adjustment (OR = 2.62; P = .03). CONCLUSIONS AND RELEVANCE: Quantitative IVCM parameters, including connective tissue organization score and the presence of dendritiform cells, are associated with disease progression and may be useful markers in trachoma and other conjunctival fibrotic diseases.
Assuntos
Gonorreia , Tracoma , Cicatriz/diagnóstico , Humanos , Microscopia Confocal , Estudos Prospectivos , Tracoma/diagnóstico , Tracoma/epidemiologiaRESUMO
OBJECTIVE: The number of adults with diabetes in sub-Saharan Africa (SSA) is expected to almost double by 2035. This study investigated the prevalence of diabetic retinopathy (DR) and its risk factors at entry into a community-based screening programme. METHODS: All persons with diabetes screened for retinopathy at entry into a screening programme in Kilimanjaro Region, Tanzania between November 2010 and December 2014 were included. Fundus photographs were taken with a Topcon retinal camera following pupil dilation. Data were collected on BP, random blood sugar, duration of diabetes, BMI and visual acuity on entry. RESULTS: A total of 3187 persons were screened for DR. The prevalence of any DR was 27.9% (95%CI 26.4-29.5%) with background diabetic retinopathy (BDR), pre-proliferative diabetic retinopathy (PPDR) and proliferative diabetic retinopathy (PDR) having a prevalence of 19.1% (95% CI 17.7-20.4%), 6.0% (95%CI 5.2-6.8%) and 2.9% (95%CI 2.3-3.5%), respectively. Maculopathy was present in 16.1% (95%CI 14.8-17.4%) of participants. Multivariable logistic regression analysis for the presence of any DR found independent associations with duration of diabetes (P < 0.0001), systolic BP (P < 0.0001), random blood sugar (P < 0.0001) and attending a government hospital diabetic clinic (P = 0.0339). CONCLUSIONS: This study is the first to present data from a DR screening programme in SSA. The results will provide policymakers with data to aid planning of DR screening and treatment services in the African region. The study highlights the importance of managing comorbidities within DR screening programmes.
Assuntos
Retinopatia Diabética/epidemiologia , Glicemia/análise , Pressão Sanguínea , Índice de Massa Corporal , Retinopatia Diabética/etiologia , Feminino , Humanos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Tanzânia/epidemiologia , Acuidade VisualRESUMO
BACKGROUND: Diabetes is an emerging public health problem in sub-Saharan Africa. Diabetic retinopathy is the commonest microvascular complication of diabetes and is a leading cause of blindness, mainly in adults of working age. Follow-up is crucial to the effective management of diabetic retinopathy, however, follow-up rates are often poor in sub-Saharan Africa. The aim of this study was to assess the proportion of patients not presenting for follow-up and the reasons for poor follow-up of diabetic patients after screening for retinopathy in Kilimanjaro Region of Tanzania. METHODS: All diabetic patients referred to a tertiary ophthalmology hospital after screening for retinopathy in 2012 were eligible for inclusion in the study. A randomly selected group of patients from the community-based diabetic retinopathy screening register were identified; among this group, follow-up was assessed. Interviews were conducted within this group to inform on the reasons for poor follow-up. RESULTS: Among the 203 patients interviewed in the study 50 patients (24.6 %) attended the recommended referral appointment and 153 (75.4 %) did not. Financial reasons were self-reported by 35.3 % of those who did not attend the follow-up appointment as the reason for non-attendance. Multiple logistic regression analysis showed that the patient report of the clarity of the referral process (p = 0.014) and the patient report of whether a healthcare worker told the patient that diabetic retinopathy could be treated (p = 0.005) were independently associated with attendance at a follow-up appointment. Income per month was not associated with attendance at a follow-up appointment on multivariate analysis. CONCLUSIONS: Financial factors are commonly cited as the reason for non-compliance with follow-up recommendations. However, the reasons for poor compliance are likely to be more complicated. This study highlights the importance of health system factors. Improving the clarity of the referral process and frequent reminders to patients that diabetic retinopathy can be treated are practical strategies that should be incorporated into screening programmes to increase attendance at subsequent follow-up appointments. The results from this study are applicable to other screening programmes as well as those for diabetic retinopathy.
Assuntos
Retinopatia Diabética/diagnóstico , Programas de Rastreamento/estatística & dados numéricos , Cooperação do Paciente/estatística & dados numéricos , Adulto , Assistência ao Convalescente , Idoso , Idoso de 80 Anos ou mais , Atitude Frente a Saúde , Estudos Transversais , Feminino , Acessibilidade aos Serviços de Saúde , Humanos , Seguro Saúde , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente/psicologia , Fatores Socioeconômicos , TanzâniaRESUMO
OBJECTIVE: To investigate the barriers to access to eye health services for patients with glaucoma in Tanzania with the aim of identifying key areas for improvement and further research. DESIGN: Qualitative investigation using face-to-face semi-structured interviews with patients recruited from the Kilimanjaro Christian Medical Centre (KCMC) outpatient eye clinic. This project is part of the international strategy of the Research into Glaucoma and Ethnicity (ReGAE) programme. METHODS: Interviews were conducted with the help of a translator; all data were transcribed in Swahili and then translated into English. Manual coding and qualitative analysis was used to identify major themes and relevant concepts. Data were collected during May and June 2013. MAIN OUTCOME MEASURES: Qualitative data on glaucoma awareness and access to healthcare. RESULTS: 12 patients (7 men, 5 women) of mean age 67.5 years (range 53-86 years) were interviewed. All participants had a previous diagnosis of glaucoma and no other eye conditions. The understanding of glaucoma was limited and the capacity for healthcare providers to improve glaucoma knowledge seemed underused. Participants had particular difficulty in understanding the aetiology and chronicity of the disease. Socioeconomic factors also posed significant barriers to service usage. CONCLUSIONS: Among many barriers to access to health services for patients with glaucoma, knowledge of the condition was identified as a key issue. Enhancing the understanding of glaucoma may improve access by triggering earlier presentation, informing those at risk and improving adherence to treatment. This is an area for further research with potential for improving service provision.
Assuntos
Atenção à Saúde/organização & administração , Glaucoma/prevenção & controle , Acessibilidade aos Serviços de Saúde/organização & administração , Optometria/organização & administração , Adulto , Idoso , Conscientização , Feminino , Glaucoma/diagnóstico , Glaucoma/epidemiologia , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Educação de Pacientes como Assunto , Atenção Primária à Saúde/organização & administração , Pesquisa Qualitativa , Tanzânia/epidemiologiaRESUMO
OBJECTIVE: To examine the reliability of clinical examination and in vivo confocal microscopy (IVCM) in distinguishing ocular surface squamous neoplasia (OSSN) from benign conjunctival lesions. DESIGN: Case-control study. PARTICIPANTS: Sixty individuals with conjunctival lesions (OSSN and benign) and 60 age-matched controls with normal conjunctiva presenting to Kilimanjaro Christian Medical Centre, Moshi, Tanzania. METHODS: Participants were examined and photographed, and IVCM was performed. Patients with conjunctival lesions were offered excisional biopsy with histopathology and a human immunodeficiency virus (HIV) test. The IVCM images were read masked to the clinical appearance and pathology results. Images were graded for several specific features and given an overall categorization (normal, benign, or malignant). A group of 8 ophthalmologists were shown photographs of conjunctival lesions and asked to independently classify as OSSN or benign. MAIN OUTCOME MEASURES: Comparison of the histopathology diagnosis with the clinical and IVCM diagnosis. RESULTS: Fifty-two cases underwent excisional biopsy with histopathology; 34 were on the OSSN spectrum, 17 were benign, and 1 was lymphoma. The cases and controls had comparable demographic profiles. Human immunodeficiency syndrome infection was more common in OSSN compared with benign cases (58.8% vs. 5.6%; odds ratio, 24.3, 95% confidence interval [CI], 2.8-204; P = 0.003). Clinically, OSSN lesions more frequently exhibited feeder vessels and tended to have more leukoplakia and a gelatinous appearance. Overall, the ophthalmologists showed moderate agreement with the histology result (average kappa = 0.51; 95% CI, 0.36-0.64). The masked grading of IVCM images reliably distinguished normal conjunctiva. However, IVCM was unable to reliably distinguish between benign lesions and OSSN because of an overlap in their appearance (kappa = 0.44; 95% CI, 0.32-0.57). No single feature was significantly more frequent in OSSN compared with benign lesions. The sensitivity and specificity of IVCM for distinguishing OSSN from benign conjunctival lesions were 38.5% and 66.7%, respectively. CONCLUSIONS: In East Africa, conjunctival pathology is relatively common and can present significant diagnostic challenges for the clinician. In this study, neither clinical examination nor IVCM was found to reliably distinguish OSSN from benign conjunctival pathology because of an overlap in the features of these groups. Therefore, IVCM cannot currently replace histopathology, and management decisions should continue to rely on careful clinical assessment supported by histopathology as indicated.
Assuntos
Carcinoma in Situ/diagnóstico , Carcinoma de Células Escamosas/diagnóstico , Neoplasias da Túnica Conjuntiva/diagnóstico , Microscopia Confocal , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma in Situ/epidemiologia , Carcinoma in Situ/virologia , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/virologia , Estudos de Casos e Controles , Neoplasias da Túnica Conjuntiva/epidemiologia , Neoplasias da Túnica Conjuntiva/virologia , Infecções Oculares Virais/diagnóstico , Infecções Oculares Virais/epidemiologia , Feminino , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tanzânia/epidemiologia , Adulto JovemRESUMO
INTRODUCTION: Globally, diabetic retinopathy (DR) is a major cause of blindness. Sub-Saharan Africa is projected to see the largest proportionate increase in the number of people living with diabetes over the next two decades. Screening for DR is recommended to prevent sight loss; however, in many low and middle-income countries, because of a lack of specialist eye care staff, current screening services for DR are not optimal. The use of artificial intelligence (AI) for DR screening, which automates the grading of retinal photographs and provides a point-of-screening result, offers an innovative potential solution to improve DR screening in Tanzania. METHODS AND ANALYSIS: We will test the hypothesis that AI-supported DR screening increases the proportion of persons with true referable DR who attend the central ophthalmology clinic following referral after screening in a single-masked, parallel group, individually randomised controlled trial. Participants (2364) will be randomised (1:1 ratio) to either AI-supported or the standard of care DR screening pathway. Participants allocated to the AI-supported screening pathway will receive their result followed by point-of-screening counselling immediately after retinal image capture. Participants in the standard of care arm will receive their result and counselling by phone once the retinal images have been graded in the usual way (typically after 2-4 weeks). The primary outcome is the proportion of persons with true referable DR attending the central ophthalmology clinic within 8 weeks of screening. Secondary outcomes, by trial arm, include the proportion of persons attending the central ophthalmology clinic out of all those referred, sensitivity and specificity, number of false positive referrals, acceptability and fidelity of AI-supported screening. ETHICS AND DISSEMINATION: The London School of Hygiene & Tropical Medicine, Kilimanjaro Christian Medical Centre and Tanzanian National Institute of Medical Research ethics committees have approved the trial. The results will be submitted to peer-reviewed journals for publication. TRIAL REGISTRATION NUMBER: ISRCTN18317152.
Assuntos
Diabetes Mellitus , Retinopatia Diabética , Humanos , Inteligência Artificial , Retinopatia Diabética/diagnóstico , Programas de Rastreamento/métodos , Sensibilidade e Especificidade , Tanzânia , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
BACKGROUND: Glaucoma staging is critical for treatment planning but has rarely been tested in severe/end-stage disease. We compared the performance of the Disc Damage Likelihood Scale (DDLS) and cup:disc ratio (CDR) using a functional glaucoma staging system (GSS) as the reference standard. METHODS: Post hoc analysis of a randomised controlled trial at the Eye Department of Kilimanjaro Christian Medical Centre, Tanzania. Eligible participants (aged ≥18 years) with open-angle glaucoma, intraocular pressure (IOP) of >21 mm Hg, were randomised to timolol 0.5% eye drops or selective laser trabeculoplasty. Fundoscopy established vertical and horizontal CDRs and DDLS. Visual acuity and static visual fields were graded (GSS). The study used area under the receiver operating characteristic (AROC) curves and Spearman's rank correlation coefficients to compare staging systems. Logistic regression with generalised estimating equations determined risk factors of functional severe/end-stage glaucoma. RESULTS: 382 eyes (201 participants) were evaluated; 195 (51%) had severe or end-stage glaucoma; mean IOP was 26.7 (SD 6.9) mm Hg. DDLS yielded an AROC of 0.90 (95% CI 0.87 to 0.93), vertical cup:disc ratio (vCDR) of 0.88 (95% CI 0.85 to 0.91, p=0.048) for identifying severe/end-stage disease. Correlation coefficients comparing GSS to DDLS and vCDRs were 0.73 and 0.71, respectively. Advanced structural stages, vision impairment, higher IOP and less financial resources were risk factors of functional severe/end-stage glaucoma. CONCLUSION: This study indicates that both structural staging systems can differentiate severe/end-stage glaucoma from less severe disease, with a moderate advantage of DDLS over CDR. Clinical examination of the optic disc plays an important role in addition to functional assessment when managing severe/end-stage glaucoma.
Assuntos
Glaucoma de Ângulo Aberto , Glaucoma , Doenças do Nervo Óptico , Humanos , Adolescente , Adulto , Glaucoma de Ângulo Aberto/diagnóstico , Glaucoma de Ângulo Aberto/cirurgia , Glaucoma de Ângulo Aberto/complicações , Doenças do Nervo Óptico/diagnóstico , Tanzânia , Pressão Intraocular , Transtornos da Visão/diagnóstico , Funções VerossimilhançaRESUMO
PRCIS: Simulation-based surgical education shows a positive, immediate, and sustained impact on core surgical skill competency in trabeculectomy among resident ophthalmologists in training. PURPOSE: To measure the impact of trabeculectomy, surgical simulation training on core surgical skill competency in resident ophthalmologists. MATERIALS AND METHODS: This is a post hoc analysis of the GLAucoma Simulated Surgery trial, which is a multicenter, multinational randomized controlled trial. Resident ophthalmologists from 6 training centers in sub-Saharan Africa (in Kenya, Uganda, Tanzania, Zimbabwe, and South Africa) were recruited according to the inclusion criteria of having performed zero surgical trabeculectomies and assisted in <5. Participants were randomly assigned to intervention and control arms using allocation concealment. The intervention was a 1-week intensive trabeculectomy surgical simulation course. Outcome measures were mean surgical competency scores in 8 key trabeculectomy surgical skills (scleral incision, scleral flap, releasable suturing, conjunctival suturing, sclerostomy, tissue handling, fluidity, and speed), using a validated scoring tool. RESULTS: Forty-nine residents were included in the intention-to-treat analysis. Baseline characteristics were balanced between arms. Median baseline surgical competency scores were 2.88/16 [interquartile range (IQR): 1.75-4.17] and 3.25/16 (IQR: 1.83-4.75) in the intervention and control arms, respectively. At primary intervention, median scores increased to 11.67/16 (IQR: 9.58-12.63) and this effect was maintained at 3 months and 1 year ( P =0.0001). Maximum competency scores at primary intervention were achieved in the core trabeculectomy skills of releasable suturing (n=17, 74%), scleral flap formation (n=16, 70%), and scleral incision (n=15, 65%) compared with scores at baseline. CONCLUSIONS: This study demonstrates the positive impact of intensive simulation-based surgical education on core trabeculectomy skill development. The rapid and sustained effect of resident skill acquisition pose strong arguments for its formal integration into ophthalmic surgical education.
Assuntos
Glaucoma , Treinamento por Simulação , Trabeculectomia , Humanos , Pressão Intraocular , Glaucoma/cirurgia , Esclera/cirurgiaRESUMO
BACKGROUND: The Kilimanjaro Diabetic Programme has been running since 2010 and screens persons with diabetes for diabetic retinopathy (DR). It was noted that women were less likely to attend follow-up appointments compared to men. The aim of this study was to explore gender biases amongst persons registered with the screening programme. METHODS: A prospective mixed-methods study was carried out using a questionnaire of closed-ended questions and a semi-structured interview guide. RESULTS: Of the 300 participants included in the quantitative component of the study, 193 (64.3%) were female and 107 (35.7%) were male. Females were significantly less educated (p < 0.001) and self-reported as less likely to attend the tertiary hospital if referred (p = 0.022). Of the married participants, on multivariate analysis, men were significantly more likely to make both financial decisions in the household (p = 0.001) and to decide if, and when, family members should attend hospital compared to women (p = 0.0048), independent of age, education level and whether they were from an urban or rural area. Qualitative analysis of the 33 interviews revealed a good understanding of the threat to vision from DR, but limited appreciation of disease chronicity. A common theme was that men are regarded as the head of the household and therefore make the financial decisions; this was especially true in less educated families. CONCLUSION: As screening and treatment facilities for DR are developed in SSA, it is important that strategies are employed to reduce the burden of blindness and visual impairment from the under-utilisation of diabetic eye care services by women.
Assuntos
Diabetes Mellitus , Retinopatia Diabética , Retinopatia Diabética/diagnóstico , Feminino , Humanos , Masculino , Programas de Rastreamento/métodos , Prevalência , Estudos Prospectivos , Sexismo , Tanzânia/epidemiologiaRESUMO
Background: Trachoma, caused by ocular infection with Chlamydia trachomatis, is a neglected tropical disease that can lead to blinding pathology. Current trachoma control programmes have successfully used mass drug administration (MDA) with azithromycin to clear C. trachomatis infection and reduce transmission, alongside promoting facial cleanliness for better personal hygiene and environmental improvement. In areas of low-trachoma endemicity, the relationship between C. trachomatis infection and trachomatous disease weakens, and non-chlamydial bacteria have been associated with disease signs. Methods: We enrolled a cohort of children aged 6-10 years from three adjacent trachoma endemic villages in Kilimanjaro and Arusha regions, Northern Tanzania. Children were divided into four clinical groups based on the presence or absence of ocular C. trachomatis infection and clinical signs of trachomatous papillary inflammation (TP). To determine the impact of treatment on the ocular microbiome in these clinical groups, we performed V4-16S rRNA sequencing of conjunctival DNA from children 3-9 months pre-MDA (n = 269) and 3 months post-MDA (n = 79). Results: Chlamydia trachomatis PCR-negative, no TP children had the highest pre-MDA ocular microbiome alpha diversity, which was reduced in C. trachomatis infected children and further decreased in those with TP. Pre-MDA, Haemophilus and Staphylococcus were associated with C. trachomatis infection with and without concurrent TP, while Helicobacter was increased in those with TP in the absence of current C. trachomatis infection. Post-MDA, none of the studied children had ocular C. trachomatis infection or TP. MDA increased ocular microbiome diversity in all clinical groups, the change was of greater magnitude in children with pre-MDA TP. MDA effectively reduced the prevalence of disease causing pathogenic non-chlamydial bacteria, and promoted restoration of a normal, healthy conjunctival microbiome. Conclusion: We identified Helicobacter as a non-chlamydial bacterium associated with the clinical signs of TP. Further investigation to determine its relevance in other low-endemicity communities is required. MDA was shown to be effective at clearing C. trachomatis infection and other non-chlamydial ocular pathogens, without any detrimental longitudinal effects on the ocular microbiome. These findings suggest that azithromycin MDA may be valuable in trachoma control even in populations where the relationship between clinical signs of trachoma and the prevalence of current ocular C. trachomatis infection has become dissociated.
Assuntos
Microbiota , Tracoma , Criança , Humanos , Tracoma/tratamento farmacológico , Tracoma/epidemiologia , Tracoma/prevenção & controle , Azitromicina/uso terapêutico , Azitromicina/farmacologia , Administração Massiva de Medicamentos , Tanzânia/epidemiologia , RNA Ribossômico 16S , Antibacterianos/uso terapêutico , Antibacterianos/farmacologia , Chlamydia trachomatis/genética , Túnica ConjuntivaRESUMO
BACKGROUND/AIM: Glaucoma accounts for 8% of global blindness and surgery remains an important treatment. We aimed to determine the impact of adding simulation-based surgical education for glaucoma. METHODS: We designed a randomised controlled, parallel-group trial. Those assessing outcomes were masked to group assignment. Fifty-one trainee ophthalmologists from six university training institutions in sub-Saharan Africa were enrolled by inclusion criteria of having performed no surgical trabeculectomies and were randomised. Those randomised to the control group received no placebo intervention, but received the training intervention after the initial 12-month follow-up period. The intervention was an intense simulation-based surgical training course over 1 week. The primary outcome measure was overall simulation surgical competency at 3 months. RESULTS: Twenty-five were assigned to the intervention group and 26 to the control group, with 2 dropouts from the intervention group. Forty-nine were included in the final intention-to-treat analysis. Surgical competence at baseline was comparable between the arms. This increased to 30.4 (76.1%) and 9.8 (24.4%) for the intervention and the control group, respectively, 3 months after the training intervention for the intervention group, a difference of 20.6 points (95% CI 18.3 to 22.9, p<0.001). At 1 year, the mean surgical competency score of the intervention arm participants was 28.6 (71.5%), compared with 11.6 (29.0%) for the control (difference 17.0, 95% CI 14.8 to 19.4, p<0.001). CONCLUSION: These results support the pursuit of financial, advocacy and research investments to establish simulation surgery training units and courses including instruction, feedback, deliberate practice and reflection with outcome measurement to enable trainee glaucoma surgeons to engage in intense simulation training for glaucoma surgery. TRIAL REGISTRATION NUMBER: PACTR201803002159198.
Assuntos
Glaucoma , Trabeculectomia , Glaucoma/cirurgia , Humanos , Quênia , África do Sul , Tanzânia , Uganda , ZimbábueRESUMO
OBJECTIVE: To characterize the tissue and cellular changes found in trachomatous scarring (TS) and inflammation using in vivo confocal microscopy (IVCM). DESIGN: Two complimentary case-control studies. PARTICIPANTS: The first study included 363 cases with TS (without trichiasis), of whom 328 had IVCM assessment, and 363 control subjects, of whom 319 had IVCM assessment. The second study included 34 cases with trachomatous trichiasis (TT), of whom 28 had IVCM assessment, and 33 control subjects, of whom 26 had IVCM assessment. METHODS: All participants were examined with ×2.5 loupes. The IVCM examination of the upper tarsal conjunctiva was carried out with a Heidelberg Retina Tomograph 3 with the Rostock Cornea Module (Heidelberg Engineering GmbH, Dossenheim, Germany). MAIN OUTCOME MEASURES: The IVCM images were graded in a masked manner using a previously published grading system evaluating the inflammatory infiltrate density; the presence or absence of dendritiform cells (DCs), tissue edema, and papillae; and the level of subepithelial connective tissue organization. RESULTS: Subjects with clinical scarring had a characteristic appearance on IVCM of well-defined bands and sheets of scar tissue visible. Similar changes were also seen in some clinically normal subjects consistent with subclinical scarring. Scarred subjects had more DCs and an elevated inflammatory infiltrate, even after adjusting for other factors, including the level of clinical inflammation. Cellular activity was usually seen only in or just below the epithelium, rarely being seen deeper than 30 µm from the surface. The presence of tissue edema was strongly associated with the level of clinical inflammation. CONCLUSIONS: In vivo confocal microscopy can be quantitatively used to study inflammatory and scarring changes in the conjunctiva. Dendritic cells seem to be closely associated with the scarring process in trachoma and are likely to be an important target in antifibrotic therapies or the development of a chlamydial vaccine. The increased number of inflammatory cells seen in scarred subjects is consistent with the immunopathologic nature of the disease. The localization of cellular activity close to the conjunctival surface supports the view that the epithelium plays a central role in the pathogenesis of trachoma. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.
Assuntos
Cicatriz/patologia , Conjuntivite de Inclusão/patologia , Edema/patologia , Microscopia Confocal , Tracoma/patologia , Triquíase/patologia , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Cicatriz/epidemiologia , Conjuntivite de Inclusão/epidemiologia , Células Dendríticas/patologia , Edema/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , População Rural , Tanzânia/epidemiologia , Tracoma/epidemiologia , Triquíase/epidemiologia , Adulto JovemRESUMO
BACKGROUND: Simulation-based surgical education (SBSE) can positively impact trainee surgical competence. However, a detailed qualitative study of the role of simulation in ophthalmic surgical education has not previously been conducted. OBJECTIVE: To explore the experiences of trainee ophthalmologists and ophthalmic surgeon educators' use of simulation, and the perceived challenges in surgical training. METHODS: A multi-center, multi-country qualitative study was conducted between October 2017 and August 2020. Trainee ophthalmologists from six training centers in sub-Saharan Africa (SSA) (in Kenya, Uganda, Tanzania, Zimbabwe and South Africa) participated in semi-structured interviews, before and after an intense simulation training course in intraocular surgery. Semi-structured interviews were also conducted with experienced ophthalmic surgeon educators. Interviews were anonymized, recorded, transcribed and coded. An inductive, bottom-up, constant comparative method was used for thematic analysis. RESULTS: Twenty-seven trainee ophthalmologists and 12 ophthalmic surgeon educators were included in the study and interviewed. The benefits and challenges of conventional surgical teaching, attributes of surgical educators, value of simulation in training and barriers to implementing ophthalmic surgical simulation were identified as major themes. Almost all trainees and trainers reported patient safety, a calm environment, the possibility of repetitive practice, and facilitation of reflective learning as beneficial aspects of ophthalmic SBSE. Perceived barriers in surgical training included a lack of surgical cases, poor supervision and limited simulation facilities. CONCLUSIONS: Simulation is perceived as an important and valuable model for education amongst trainees and ophthalmic surgeon educators in SSA. Advocating for the expansion and integration of educationally robust simulation surgical skills centers may improve the delivery of ophthalmic surgical education throughout SSA.
Assuntos
Treinamento por Simulação , Cirurgiões , Competência Clínica , Simulação por Computador , Humanos , TanzâniaRESUMO
Importance: Cataracts account for 40% of cases of blindness globally, with surgery the only treatment. Objective: To determine whether adding simulation-based cataract surgical training to conventional training results in improved acquisition of surgical skills among trainees. Design, Setting, and Participants: A multicenter, investigator-masked, parallel-group, randomized clinical educational-intervention trial was conducted at 5 university hospital training institutions in Kenya, Tanzania, Uganda, and Zimbabwe from October 1, 2017, to September 30, 2019, with a follow-up of 15 months. Fifty-two trainee ophthalmologists were assessed for eligibility (required no prior cataract surgery as primary surgeon); 50 were recruited and randomized. Those assessing outcomes of surgical competency were masked to group assignment. Analysis was performed on an intention-to-treat basis. Interventions: The intervention group received a 5-day simulation-based cataract surgical training course, in addition to standard surgical training. The control group received standard training only, without a placebo intervention; however, those in the control group received the intervention training after the initial 12-month follow-up period. Main Outcomes and Measures: The primary outcome measure was overall surgical competency at 3 months, which was assessed with a validated competency assessment rubric. Secondary outcomes included surgical competence at 1 year and quantity and outcomes (including visual acuity and posterior capsule rupture) of cataract surgical procedures performed during a 1-year period. Results: Among the 50 participants (26 women [52.0%]; mean [SD] age, 32.3 [4.6] years), 25 were randomized to the intervention group, and 25 were randomized to the control group, with 1 dropout. Forty-nine participants were included in the final intention-to-treat analysis. Baseline characteristics were balanced. The participants in the intervention group had higher scores at 3 months compared with the participants in the control group, after adjusting for baseline assessment rubric score. The participants in the intervention group were estimated to have scores 16.6 points (out of 40) higher (95% CI, 14.4-18.7; P < .001) at 3 months than the participants in the control group. The participants in the intervention group performed a mean of 21.5 cataract surgical procedures in the year after the training, while the participants in the control group performed a mean of 8.5 cataract surgical procedures (mean difference, 13.0; 95% CI, 3.9-22.2; P < .001). Posterior capsule rupture rates (an important complication) were 7.8% (42 of 537) for the intervention group and 26.6% (54 of 203) for the control group (difference, 18.8%; 95% CI, 12.3%-25.3%; P < .001). Conclusions and Relevance: This randomized clinical trial provides evidence that intense simulation-based cataract surgical education facilitates the rapid acquisition of surgical competence and maximizes patient safety. Trial Registration: Pan-African Clinical Trial Registry, number PACTR201803002159198.
Assuntos
Extração de Catarata/educação , Instrução por Computador , Educação de Pós-Graduação em Medicina , Treinamento com Simulação de Alta Fidelidade , Oftalmologistas/educação , Cirurgiões/educação , Adulto , África Subsaariana , Competência Clínica , Currículo , Escolaridade , Feminino , Humanos , Curva de Aprendizado , Masculino , Fatores de TempoRESUMO
BACKGROUND: Glaucoma is a major cause of sight loss worldwide, with the highest regional prevalence and incidence reported in Africa. The most common low-cost treatment used to control glaucoma is long-term timolol eye drops. However, low adherence is a major challenge. We aimed to investigate whether selective laser trabeculoplasty (SLT) was superior to timolol eye drops for controlling intraocular pressure (IOP) in patients with open-angle glaucoma. METHODS: We did a two-arm, parallel-group, single-masked randomised controlled trial at the Eye Department of Kilimanjaro Christian Medical Centre, Moshi, Tanzania. Eligible participants (aged ≥18 years) had open-angle glaucoma and an IOP above 21 mm Hg, and did not have asthma or a history of glaucoma surgery or laser. Participants were randomly assigned (1:1) to receive 0·5% timolol eye drops to administer twice daily or to receive SLT. The primary outcome was the proportion of eyes from both groups with treatment success, defined as an IOP below or equal to target pressure according to glaucoma severity, at 12 months following randomisation. Re-explanation of eye drop application or a repeat SLT was permitted once. The primary analysis was by modified intention-to-treat, excluding participants lost to follow-up, using logistic regression; generalised estimating equations were used to adjust for the correlation between eyes. This trial was registered with the Pan African Clinical Trials Registry, number PACTR201508001235339. FINDINGS: 840 patients were screened for eligibility, of whom 201 (24%) participants (382 eligible eyes) were enrolled between Aug 31, 2015, and May 12, 2017. 100 (50%) participants (191 eyes) were randomly assigned to the timolol group and 101 (50%; 191 eyes) to the SLT group. After 1 year, 339 (89%) of 382 eyes were analysed. Treatment was successful in 55 (31%) of 176 eyes in the timolol group (16 [29%] of 55 eyes required repeat administration counselling) and in 99 (61%) of 163 eyes in the SLT group (33 [33%] of 99 eyes required repeat SLT; odds ratio 3·37 [95% CI 1·96-5·80]; p<0·0001). Adverse events (mostly unrelated to ocular events) occurred in ten (10%) participants in the timolol group and in eight (8%) participants in the SLT group (p=0·61). INTERPRETATION: SLT was superior to timolol eye drops for managing patients with open-angle high-pressure glaucoma for 1 year in Tanzania. SLT has the potential to transform the management of glaucoma in sub-Saharan Africa, even where the prevalence of advanced glaucoma is high. FUNDING: Christian Blind Mission, Seeing is Believing Innovation Fund, and the Wellcome Trust. TRANSLATIONS: For the Kiswahili, French and Portuguese translations of the abstract see Supplementary Materials section.
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Glaucoma/terapia , Terapia a Laser/métodos , Soluções Oftálmicas/uso terapêutico , Timolol/uso terapêutico , Trabeculectomia/métodos , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tanzânia , Adulto JovemRESUMO
Purpose: To compare severity of visual field (VF) loss at first presentation in glaucoma clinics in England and Tanzania.Methods: Large archives of VF records from automated perimetry were used to retrospectively examine vision loss at first presentation in glaucoma clinics in Tanzania (N = 1,502) and England (N = 9,264). Mean deviation (MD) of the worse eye at the first hospital visit was used as an estimate of detectable VF loss severity.Results: In Tanzania, 44.7% {CI95%: 42.2, 47.2} of patients presented with severe VF loss (< -20 dB), versus 4.6% {4.1, 5.0} in England. If we consider late presentation to also include cases of advanced loss (-12.01 dB to -20 dB), then the proportion of patients presenting late was 58.1% {55.6, 60.6} and 14.0% {13.3, 14.7}, respectively. The proportion of late presentations was greater in Tanzania at all ages, but the difference was particularly pronounced among working-age adults, with 50.3% {46.9, 53.7} of 18-65-year-olds presenting with advanced or severe VF loss, versus 10.2% {9.3, 11.3} in England. In both countries, men were more likely to present late than women.Conclusions: Late presentation of glaucoma is a problem in England, and an even greater challenge in Tanzania. Possible solutions are discussed, including increased community eye-care, and a more proactive approach to case finding through the use of disruptive new technologies, such as low-cost, portable diagnostic aids.
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Diagnóstico Tardio/estatística & dados numéricos , Glaucoma/diagnóstico , Transtornos da Visão/diagnóstico , Testes de Campo Visual/métodos , Campos Visuais/fisiologia , Adulto , Idoso , Diagnóstico Precoce , Inglaterra/epidemiologia , Feminino , Glaucoma/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Índice de Gravidade de Doença , Tanzânia/epidemiologia , Transtornos da Visão/epidemiologia , Transtornos da Visão/etiologiaRESUMO
Background: There are 2.7 ophthalmologists per million population in sub-Saharan Africa, and a need to train more. We sought to analyse current surgical training practice and experience of ophthalmologists to inform planning of training in Eastern, Central and Southern Africa. Methods: This was a cross-sectional survey. Potential participants included all current trainee and recent graduate ophthalmologists in the Eastern, Central and Southern African region. A link to a web-based questionnaire was sent to all heads of eye departments and training programme directors of ophthalmology training institutions in Eastern, Central and Southern Africa, who forwarded to all their trainees and recent graduates. Main outcome measures were quantitative and qualitative survey responses. Results: Responses were obtained from 124 (52%) trainees in the region. Overall level of satisfaction with ophthalmology training programmes was rated as 'somewhat satisfied' or 'very satisfied' by 72%. Most frequent intended career choice was general ophthalmology, with >75% planning to work in their home country post-graduation. A quarter stated a desire to mainly work in private practice. Only 28% of junior (first and second year) trainees felt surgically confident in manual small incision cataract surgery (SICS); this increased to 84% among senior trainees and recent graduates. The median number of cataract surgeries performed by junior trainees was zero. 57% of senior trainees were confident in performing an anterior vitrectomy. Only 29% of senior trainees and 64% of recent graduates were confident in trabeculectomy. The mean number of cataract procedures performed by senior trainees was 84 SICS (median 58) and 101 phacoemulsification (median 0). Conclusion: Satisfaction with post-graduate ophthalmology training in the region was fair. Most junior trainees experience limited cataract surgical training in the first two years. Focused efforts on certain aspects of surgical education should be made to ensure adequate opportunities are offered earlier on in ophthalmology training.
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BACKGROUND: Trachoma is a progressive blinding disease initiated by infection of the conjunctiva with Chlamydia trachomatis. Repeated infections are thought to cause chronic inflammation, which drives scarring, leading to in-turning of the eyelids. The relationship between C. trachomatis, clinical inflammation and scarring development in children is not fully understood due to a paucity of longitudinal studies with infection data at frequent follow-up. METHODS AND FINDINGS: This longitudinal cohort study took place in northern Tanzania. Children aged 6-10 years at baseline were eligible for inclusion. Participants were visited every three months for four years. Clinical signs and conjunctival swabs for C. trachomatis detection by qPCR were collected at each time-point. Conjunctival photographs from baseline and final time-points were graded and compared side-by-side to determine scarring incidence and progression. Of the 666 children enrolled in the study, outcome data were obtained for 448. Scarring progression was detected in 103/448 (23%) children; 48 (11%) of which had incident scarring and 55 (12%) had progression of existing scarring. Scarring was strongly associated with increasing episodes of trachomatous papillary inflammation (TP). Weaker associations were found between episodes of C. trachomatis infection and follicular trachoma (TF) with scarring progression in unadjusted models, which were absent in multivariable analysis after adjusting for inflammation (multivariable results: C. trachomatis p = 0.44, TF p = 0.25, TP p = <0.0001, age p = 0.13, female sex p = 0.05). Individuals having TP at 30% or more of the time-points they were seen had an odds ratio of 7.5 (95%CI = 2.7-20.8) for scarring progression relative to individuals without any TP detected during the study period. CONCLUSIONS: These data suggest that the effect of infection on scarring progression is mediated through papillary inflammation, and that other factors contributing to the development of inflammation, in addition to C. trachomatis infection, may be important in driving conjunctival scarring progression in children. The addition of TP as a measure in trachoma control programs would provide an indication of the future risk of developing scarring sequelae.
Assuntos
Chlamydia trachomatis/patogenicidade , Cicatriz/epidemiologia , Progressão da Doença , Tracoma/epidemiologia , Criança , Chlamydia trachomatis/isolamento & purificação , Estudos de Coortes , Túnica Conjuntiva/diagnóstico por imagem , Feminino , Humanos , Incidência , Inflamação , Estudos Longitudinais , Masculino , Razão de Chances , Fatores de Risco , Tanzânia/epidemiologiaRESUMO
BACKGROUND: Trachoma, caused by Chlamydia trachomatis, remains the leading infectious cause of blindness worldwide. Persistence and progression of the resulting clinical disease appears to be an immunologically mediated process. Azithromycin, which is distributed at the community level for trachoma control, has immunomodulatory properties. We investigated the impact of one round of oral azithromycin on conjunctival immune responses, C. trachomatis infection and clinical signs three- and six- months post treatment relative to three pre-treatment time-points. METHODOLOGY: A cohort of children aged 6 to 10 years were recruited from a trachoma endemic region of northern Tanzania and were visited five times in a 12-month period. They were examined for clinical signs of trachoma and conjunctival swabs were collected for laboratory analysis. C. trachomatis infection was detected and the expression of 46 host genes was quantified using quantitative PCR. All community members were offered azithromycin treatment immediately after the six-month timepoint according to international guidelines. FINDINGS: The prevalence of C. trachomatis infection and inflammatory disease signs were significantly reduced three- and six- months post-mass drug administration (MDA). C. trachomatis infection was strongly associated with clinical signs at all five time-points. A profound anti-inflammatory effect on conjunctival gene expression was observed 3 months post-MDA, however, gene expression had largely returned to pre-treatment levels of variation by 6 months. This effect was less marked, but still observed, after adjusting for C. trachomatis infection and when the analysis was restricted to individuals who were free from both infection and clinical disease at all five time-points. Interestingly, a modest effect was also observed in individuals who did not receive treatment. CONCLUSION: Conjunctival inflammation is the major clinical risk factor for progressive scarring trachoma, therefore, the reduction in inflammation associated with azithromycin treatment may be beneficial in limiting the development of potentially blinding disease sequelae. Future work should seek to determine whether this effect is mediated directly through inhibition of pro-inflammatory intracellular signalling molecules, through reductions in concurrent, sub-clinical infections, and/or through reduction of infection exposure.