Browsing by Author "Onyango, John"

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    Corneal endothelial cell density and associated factors among adults at a regional referral hospital in Uganda: a cross-sectional study
    (BioMed Central Ltd, 2024-04-15) Namwase, Shamiim; Ruvuma, Sam; Onyango, John; Kwaga, Teddy; Ebong, Abel; Atwine, Daniel; Mukunya, David; Arunga, Simon
    Background To assess the prevalence of low corneal endothelial cell density and correlates of corneal endothelial cell density among adults attending Mbarara University and Referral Hospital Eye Centre in Uganda. Methods In this hospital-based cross-sectional study, participants 18 years and older, were enrolled. We obtained informed consent, and basic demographic data. We also conducted visual acuity, a detailed slit lamp examination, intra-ocular pressure, corneal diameter, tear-film break-up time, keratometry, A-scan, and pachymetry on all participants. A confocal microscope Heidelberg HRT3 was used to examine the central cornea and to obtain the mean cell density (cells/mm.sup.2). To calculate the proportion of low endothelial cell density, descriptive statistics were used, whereas correlates of endothelial cell density were assessed, using linear regression analyses. Results We evaluated a total of 798 eyes of 404 participants aged between 18 and 90 years (males = 187, females = 217). The average endothelial cell density was 2763.6 cells/mm.sup.2, and there was a decrease in endothelial cell density with increasing age, irrespective of gender. There was no significant difference in endothelial cell density between males and females. Increasing age (adjusted coefficient - 10.1, p < 0.001), history of smoking (adjusted coefficient - 439.6, p = 0.004), history of ocular surgery (adjusted coefficient - 168.0, p = 0.023), having dry eye (adjusted coefficient - 136.0, p = 0.051), and having arcus senilis (adjusted coefficient - 132.0, p = 0.08), were correlated with lower endothelial cell density. However, increasing corneal diameter (adjusted coefficient 134.0, p = 0.006), increasing central corneal thickness (adjusted coefficient 1.2, p = 0.058), and increasing axial length (adjusted coefficient 65.8, p = 0.026), were correlated with higher endothelial cell density. We found five eyes (0.63%) from different participants with a low endothelial cell density (< 1000cells/mm.sup.2). Conclusion Our study established baseline normal ranges of ECD in a predominantly black African population, and found that low ECD is rare in our population. The elderly, smokers, and those with past ocular surgery are the most vulnerable. The low prevalence could be due to a lack of reference values for the black African population. Keywords: Cornea, Endothelial cell density, Uganda
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    Epidemiology of Microbial Keratitis in Uganda: A Cohort Study
    (Ophthalmic Epidemiology, 2020) Arunga, Simon; Kintoki, Guyguy M.; Mwesigye, James; Ayebazibwe, Bosco; Onyango, John; Bazira, Joel; Newton, Rob; Gichuhi, Stephen; Leck, Astrid; Macleod, David; Hu, Victor H.; Burton, Matthew J.
    To describe the epidemiology of Microbial Keratitis (MK) in Uganda. Methods: We prospectively recruited patients presenting with MK at two main eye units in Southern Uganda between December 2016 and March 2018. We collected information on clinical history and presentation, microbiology and 3-month outcomes. Poor vision was defined as vision < 6/60). Results: 313 individuals were enrolled. Median age was 47 years (range 18–96) and 174 (56%) were male. Median presentation time was 17 days from onset (IQR 8–32). Trauma was reported by 29% and use of Traditional Eye Medicine by 60%. Majority presented with severe infections (median infiltrate size 5.2 mm); 47% were blind in the affected eye (vision < 3/60). Microbiology was available from 270 cases: 62% were fungal, 7% mixed (bacterial and fungal), 7% bacterial and 24% no organism detected. At 3 months, 30% of the participants were blind in the affected eye, while 9% had lost their eye from the infection. Delayed presentation (overall p = .007) and prior use of Traditional Eye Medicine (aOR 1.58 [95% CI 1.04–2.42], p = .033) were responsible for poor presentation. Predictors of poor vision at 3 months were: baseline vision (aOR 2.98 [95%CI 2.12–4.19], p < .0001), infiltrate size (aOR 1.19 [95%CI 1.03–1.36], p < .020) and perforation at presentation (aOR 9.93 [95% CI 3.70–26.6], p < .0001). Conclusion: The most important outcome predictor was the state of the eye at presentation, facilitated by prior use of Traditional Eye Medicine and delayed presentation. In order to improve outcomes, we need effective early interventions.
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    The impact of microbial keratitis on quality of life in Uganda
    (BMJ Open Ophthalmology, 2019) Arunga, Simon; Wiafe, Geoffrey; Habtamu, Esmael; Onyango, John; Gichuhi, Stephen; Leck, Astrid; Macleod, David; Hu, Victor; Burton, Matthew
    Microbial keratitis (MK) is a frequent cause of sight loss in sub-Saharan Africa. However, no studies have formally measured its impact on quality of life (QoL) in this context. Methods As part of a nested case–control design for risk factors of MK, we recruited patients presenting with MK at two eye units in Southern Uganda between December 2016 and March 2018 and unaffected individuals, individually matched for sex, age and location. QoL was measured using WHO Health-Related and Vision-Related QoL tools (at presentation and 3 months after start of treatment in cases). Mean QoL scores for both groups were compared. Factors associated with QoL among the cases were analysed in a linear regression model. Results 215 case-controls pairs were enrolled. The presentation QoL scores for the cases ranged from 20 to 65 points. The lowest QoL was visual symptom domain; mean 20.7 (95% CI 18.8 to 22.7) and the highest was psychosocial domain; mean 65.6 (95% CI 62.5 to 68.8). At 3 months, QoL scores for the patients ranged from 80 to 90 points while scores for the controls ranged from 90 to 100. The mean QoL scores of the cases were lower than controls across all domains. Determinants of QoL among the cases at 3 months included visual acuity at 3 months and history of eye loss. Conclusion MK severely reduces QoL in the acute phase. With treatment and healing, QoL subsequently improves. Despite this improvement, QoL of someone affected by MK (even with normal vision) remains lower than unaffected controls.
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    The management of microbial keratitis within Uganda’s primary health system: a situational analysis [version 1; peer review: 3 approved]
    (Wellcome Open Research, 2019) Arunga, Simon; Kyomugasho, Naome; Kwaga, Teddy; Onyango, John; Leck, Astrid; Macleod, David; Hu, Victor; Burton, Matthew
    Microbial keratitis (MK) frequently leads to sight-loss, especially when the infection is severe and/or appropriate treatment is delayed. The primary health system as an entry point plays a central role in facilitating and directing patient access to appropriate care. The purpose of this study was to describe the capacity of primary health centres in Uganda in managing MK. Methods: We carried out a rigorous assessment of primary health centres and mid-cadre training schools in South Western Uganda. Through interviews, checklists and a picture quiz, we assessed capacity and knowledge of MK management. In addition, we interviewed the heads of all the mid-cadre training schools to determine the level of eye health training provided in their curricula. Results: In total, 163 health facilities and 16 training schools were enrolled. Of the health facilities, only 6% had an Ophthalmic Clinical Officer. Only 12% of the health workers could make a diagnosis of MK based on the clinical signs in the picture quiz. Although 35% of the facilities had a microscope, none reported doing corneal scraping. None of the facilities had a stock of the recommended first line treatment options for MK (ciprofloxacin and natamycin eye drops). Among the training schools, 15/16 had an eye health component in the curriculum. However, the majority (56%) of tutors had no formal expertise in eye health. In 14/16 schools, students spent an average of two weeks in an eye unit. Conclusions: Knowledge among health workers and capacity of health facilities in diagnosis and management of MK was low. Training for eye health within mid-cadre training schools was inadequate. More is needed to close these gaps in training and capacity.
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    The management of microbial keratitis within Uganda’s primary health system: a situational analysis [version 1; peer review: 3 approved]
    (Wellcome Open Research, 2019) Arunga, Simon; Kyomugasho, Naome; Kwaga, Teddy; Onyango, John; Leck, Astrid; Macleod, David; Hu, Victor; Burton, Matthew
    Microbial keratitis (MK) frequently leads to sight-loss, especially when the infection is severe and/or appropriate treatment is delayed. The primary health system as an entry point plays a central role in facilitating and directing patient access to appropriate care. The purpose of this study was to describe the capacity of primary health centres in Uganda in managing MK. Methods: We carried out a rigorous assessment of primary health centres and mid-cadre training schools in South Western Uganda. Through interviews, checklists and a picture quiz, we assessed capacity and knowledge of MK management. In addition, we interviewed the heads of all the mid-cadre training schools to determine the level of eye health training provided in their curricula. Results: In total, 163 health facilities and 16 training schools were enrolled. Of the health facilities, only 6% had an Ophthalmic Clinical Officer. Only 12% of the health workers could make a diagnosis of MK based on the clinical signs in the picture quiz. Although 35% of the facilities had a microscope, none reported doing corneal scraping. None of the facilities had a stock of the recommended first line treatment options for MK (ciprofloxacin and natamycin eye drops). Among the training schools, 15/16 had an eye health component in the curriculum. However, the majority (56%) of tutors had no formal expertise in eye health. In 14/16 schools, students spent an average of two weeks in an eye unit. Conclusions: Knowledge among health workers and capacity of health facilities in diagnosis and management of MK was low. Training for eye health within mid-cadre training schools was inadequate. More is needed to close these gaps in training and capacity.
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    Outcome of intravitreal Avastin® injections in patients with macular oedema in Uganda: a cohort study
    (Eye, 2022) Kabunga, Rachel R.; Onyango, John; Ruvuma, Sam; Arunga, Simon
    To determine the outcome of Intravitreal Avastin (IVA) injections in patients with Macular Oedema (MO) in Uganda. METHODS: We prospectively recruited patients presenting with MO at the Department of Ophthalmology of Mbarara University of Science and Technology in Southern Uganda from November 2018 to April 2019. We treated them with intravitreal injection of Bevacizumab (Avastin®) and followed them up for three consecutive months after the initial injection. We collected information on baseline clinical presentation and 3 month outcomes. We performed a Student’s t-test to compare central macular thickness (CMT) and best corrected visual acuity (BCVA) at baseline and at 3 months after IVA injections. We performed linear regression to test for predictors of change in CMT and BCVA at 3 months. RESULTS: We enroled 32 patients (35 eyes) of which 29 patients (32 eyes) completed the follow up. The mean age was 62.8 ± 11.8 years, and 53% were male. At 3 months after IVA, the mean CMT improved significantly from 426.90 ± 135.9 μm at baseline to 311.20 ± 134.80 μm (p = 0.0008). The mean BCVA improved from 0.70 ± 0.38 at baseline to 0.38 ± 0.36 logMAR units (p = 0.003). The improvement in CMT and BCVA were more marked in patients who had Diabetic ME compared to other causes. A high baseline CMT was a strong predictor of improvement in CMT at 3 months after IVA therapy. A worse baseline visual acuity was a predictor of improvement in vision at 3 months after IVA. CONCLUSIONS: IVA therapy results in anatomical and visual improvement at 3 months especially in patients with Diabetic MO. Having a high baseline CMT was a predictor of good CMT outcome at 3 months while a worse vision at baseline was a predictor of better visual outcome at 3 months.
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    Traditional eye medicine use in microbial keratitis in Uganda: a mixed methods study [version 1; peer review: awaiting peer review]
    (Wellcome open research, 2019) Arunga, Simon; Asiimwe, Allen; Apio Olet, Eunice; Kagoro-Rugunda, Grace; Ayebazibwe, Bosco; Onyango, John; Newton, Robert; Leck, Astrid; Macleod, David; Hu, Victor H.; Seeley, Janet; Burton, Matthew J.
    Traditional eye medicine (TEM) is frequently used to treat microbial keratitis (MK) in many parts of Africa. Few reports have suggested that this is associated with a worse outcome. We undertook this large prospective study to determine how TEM use impacts presentation and outcome of MK and to explore reasons why people use TEM for treatment in Uganda. Methods: In a mixed method prospective cohort study, we enrolled patients presenting with MK at the two main eye units in Southern Uganda between December 2016 and March 2018 and collected information on history, TEM use, microbiology and 3-month outcomes. We conducted qualitative interviews with patients, carers traditional healers on reasons why people use TEM. Outcome measures included presenting vision and at 3-months, comparing TEM Users versus Non-Users. A thematic coding framework was deployed to explore reasons for use of TEM. Results: 188 out of 313 participants reported TEM use. TEM Users had a delayed presentation; median presenting time 18 days versus 14 days, p= 0.005; had larger ulcers 5.6 mm versus 4.3 mm p=0.0005; a worse presenting visual acuity median logarithm of the minimum angle of resolution (Log MAR) 1.5 versus 0.6, p=0.005; and, a worse visual acuity at 3 months median Log MAR 0.6 versus 0.2, p=0.010. In a multivariable logistic regression model, distance from the eye hospital and delayed presentation were associated with TEM use. Reasons for TEM use included lack of confidence in conventional medicine, health system breakdown, poverty, fear of the eye hospital, cultural belief in TEM, influence from traditional healers, personal circumstances and ignorance. : TEM users h Conclusion ad poorer clinical presentation and outcomes. Capacity building of the primary health centres to improve access to eye care and community behavioural change initiatives against TEM use should be encouraged.