Pretreatment ocular blood flow and retinal oxygen metabolism in the acute uveitic phase is associated with final outcome in Vogt-Koyanagi-Harada disease

PURPOSE

To investigate the association between pretreatment blood flow velocity in the choroid and optic nerve head (ONH) and retinal oxygen metabolism in the acute uveitic phase and the development of 'sunset glow fundus' in Vogt-Koyanagi-Harada (VKH) disease.

METHODS

Retrospective analysis of 41 patients (82 eyes). Laser speckle flowgraphy and retinal oximetry measurements were performed at the presentation. The main outcome measure was the development of 'sunset glow fundus'.

RESULTS

Twenty patients (40 eyes) presented in the phase preceding anterior segment inflammation (early presentation), and 21 patients (42 eyes) presented with anterior segment inflammation (late presentation). In ONH, mean blur rate (MBR)-vessel, representing blood flow velocity in retinal vessels, was significantly lower in the late presentation group, while choroidal MBR was not significantly different. The late presentation group had significantly lower oxygen saturation in retinal venules, a higher arteriovenous oxygen saturation difference and a smaller calibre of retinal arterioles compared with the early presentation group. Eyes that subsequently developed 'sunset glow fundus' had significantly lower ONH MBR-vessels, lower oxygen saturation in retinal venules, a higher arteriovenous oxygen saturation difference and a smaller calibre of retinal arterioles compared with eyes without 'sunset glow fundus'. ONH MBR-vessel had a significant negative correlation with arteriovenous oxygen saturation difference and a significant positive correlation with calibre of retinal arterioles.

CONCLUSIONS

In the acute uveitic phase of VKH disease, the development of 'sunset glow fundus' is associated with pretreatment reduced retinal blood flow velocity, calibre of retinal arterioles and oxygen saturation in retinal venules, as well as an increased arteriovenous oxygen saturation difference.

Comparisons of choroidal blood flow velocity between initial-onset acute uveitis associated with Vogt-Koyanagi-Harada disease and acute central serous chorioretinopathy

OBJECTIVES

Acute central serous chorioretinopathy (CSC) and Vogt-Koyanagi-Harada (VKH) disease in the acute uveitic phase are characterized by serous retinal detachment caused by dysfunction of the choroid. The aim of this study is to compare blood flow velocity and pulse waveform parameters in the choroid between these two diseases.

METHODS

In this study, 25 patients (50 eyes) with VKH disease, 21 patients (27 eyes) with CSC and 15 healthy controls (30 eyes) were studied. Laser speckle flowgraphy (LSFG) was performed at presentation.

RESULTS

Choroidal mean blur rate (MBR), representing blood flow velocity in choroidal vessels, was significantly lower in the eyes affected by VKH disease compared with the healthy control and CSC eyes. CSC eyes had a significantly higher MBR compared with healthy controls. Among the analyzed pulse waveform parameters, blow-out time (BOT), falling rate (FR) and flow acceleration index (FAI) changed significantly. BOT value was significantly lower in CSC eyes than in healthy control and VKH eyes. FR and FAI values were significantly lower in VKH eyes than in healthy control and CSC eyes. There was a strong positive correlation between MBR and FAI.

CONCLUSIONS

Our findings confirm different pathophysiology of these two diseases. Assessment of choroidal blood flow velocity and haemodynamics with LSFG provides useful information to differentiate acute CSC and initial-onset acute uveitis associated with VKH disease.

CD40 Ligand-CD40 Interaction Is an Intermediary between Inflammation and Angiogenesis in Proliferative Diabetic Retinopathy

We aimed to investigate the role of the CD40-CD40 ligand (CD40L) pathway in inflammation-mediated angiogenesis in proliferative diabetic retinopathy (PDR). We analyzed vitreous fluids and epiretinal fibrovascular membranes from PDR and nondiabetic patients, cultures of human retinal microvascular endothelial cells (HRMECs) and Müller glial cells and rat retinas with ELISA, immunohistochemistry, flow cytometry and Western blot analysis. Functional tests included measurement of blood-retinal barrier breakdown, in vitro angiogenesis and assessment of monocyte-HRMEC adherence. CD40L and CD40 levels were significantly increased in PDR vitreous samples. We demonstrated CD40L and CD40 expression in vascular endothelial cells, leukocytes and myofibroblasts in epiretinal membranes. Intravitreal administration of soluble (s)CD40L in normal rats significantly increased retinal vascular permeability and induced significant upregulation of phospho-ERK1/2, VEGF, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1). sCD40L induced upregulation of VEGF, MMP-9, MCP-1 and HMGB1 in cultured Müller cells and phospo-ERK1/2, p65 subunit of NF-ĸB, VCAM-1 and VEGF in cultured HRMECS. TNF-α induced significant upregulation of CD40 in HRMECs and Müller cells and VEGF induced significant upregulation of CD40 in HRMECs. sCD40L induced proliferation and migration of HRMECs. We provide experimental evidence supporting the involvement of the CD40L-CD40 pathway and how it regulates inflammatory angiogenesis in PDR.

Macrophage-Myofibroblast Transition Contributes to Myofibroblast Formation in Proliferative Vitreoretinal Disorders

Inflammation and fibrosis are key features of proliferative vitreoretinal disorders. We aimed to define the macrophage phenotype and investigate the role of macrophage-myofibroblast transition (MMT) in the contribution to myofibroblast populations present in epiretinal membranes. Vitreous samples from proliferative diabetic retinopathy (PDR), proliferative vitreoretinopathy (PVR) and nondiabetic control patients, epiretinal fibrovascular membranes from PDR patients and fibrocellular membranes from PVR patients, human retinal Müller glial cells and human retinal microvascular endothelial cells (HRMECs) were studied by ELISA, immunohistochemistry and flow cytometry analysis. Myofibroblasts expressing α-SMA, fibroblast activation protein-α (FAP-α) and fibroblast-specific protein-1 (FSP-1) were present in all membranes. The majority of CD68+ monocytes/macrophages co-expressed the M2 macrophage marker CD206. In epiretinal membranes, cells undergoing MMT were identified by co-expression of the macrophage marker CD68 and myofibroblast markers α-SMA and FSP-1. Further analysis revealed that CD206+ M2 macrophages co-expressed α-SMA, FSP-1, FAP-α and ß-catenin. Soluble (s) CD206 and sFAP-α levels were significantly higher in vitreous samples from PDR and PVR patients than in nondiabetic control patients. The proinflammatory cytokine TNF-α and the hypoxia mimetic agent cobalt chloride induced upregulation of sFAP-α in culture media of Müller cells but not of HRMECs. The NF-ĸß inhibitor BAY11-7085 significantly attenuated TNF-α-induced upregulation of sFAP-α in Müller cells. Our findings suggest that the process of MMT might contribute to myofibroblast formation in epiretinal membranes, and this transition involved macrophages with a predominant M2 phenotype. In addition, sFAP-α as a vitreous biomarker may be derived from M2 macrophages transitioned to myofibroblasts and from Müller cells.

Therapeutic window of opportunity in the acute uveitic phase of Vogt-Koyanagi-Harada disease: Prevention of late autoimmune complications by early intervention

PURPOSE

To determine relationship between timing of treatment initiation and disease outcomes and whether a therapeutic window of opportunity exists in initial-onset acute uveitis associated with Vogt-Koyanagi-Harada disease.

METHODS

Retrospective analysis of 112 patients (224 eyes). Main outcome measures were final visual acuity, progression to chronic recurrent evolution, development of complications, particularly 'sunset glow fundus', and drug-free remission cure of uveitis.

RESULTS

Forty-six patients (92 eyes) presented in the phase preceding anterior segment (AS) inflammation (early presentation) and 66 patients (132 eyes) had AS inflammation at presentation (late presentation). In significantly more eyes in the early presentation group (85.9%), final visual acuity of 20/20 was achieved compared with those in the late presentation group (66.7%) (p = 0.001). None of the eyes in the early presentation group progressed to chronic recurrent evolution and none developed 'sunset glow fundus', whereas in the late presentation group, 28.8% of the eyes progressed to chronic recurrent evolution (p < 0.001) and 56.1% developed 'sunset glow fundus' (p < 0.001). Patients in the early presentation group were able to discontinue treatment without relapse of inflammation at significantly shorter time intervals compared to patients in the delayed presentation group (p < 0.001). In the late presentation group, logistic regression analysis demonstrated that presenting clinical features predicting unfavourable outcomes were posterior synechiae (odds ratio = 4.03; 95% confidence interval [CI] = 1.29-12.23), bullous exudative retinal detachment extending to the periphery (odds ratio = 3.35; 95% CI = 1.53-7.32) and female gender (odds ratio = 2.05; CI = 1.08-3.90).

CONCLUSIONS

Our findings suggest that the window of opportunity lies in the phase preceding AS inflammation and initiation of effective treatment during this phase results in cure of uveitis and prevents blinding complications.

Clinical Findings Predicting Posttraumatic Endophthalmitis after Repair of Open Globe Injuries

BACKGROUND

To evaluate risk factors for developing endophthalmitis after repair of open globe injuries.

METHODS

Retrospective chart analysis of 1303 patients from May 1996 till December 2019.

RESULTS

All patients received prophylactic intravenous broad-spectrum antibiotics for 5-7 days. Endophthalmitis was clinically suspected in 37 (2.8%) eyes and was culture proven in 14 of these eyes (1.1%). Univariate analysis identified poor initial visual acuity at presentation, rural setting of injury, contaminated wound and lens injury as significant predictors for the development of clinically suspected endophthalmitis. Intravitreal antibiotics at the time of primary repair in eyes with high-risk characteristics decreased risk of developing endophthalmitis (OR: 2.28;95% CI,1.07-4.86; p = .033).

CONCLUSIONS

Poor initial visual acuity, rural setting of injury, contaminated wound, and lens injury increased risk of suspected posttraumatic endophthalmitis. Prophylactic intravitreal antibiotics at the time of primary repair in eyes with high-risk characteristics reduced the risk of posttraumatic endophthalmitis.

Long-term Outcomes of Uveitis Associated with Vogt-Koyanagi-Harada Disease in the Pediatric Age Group

PURPOSE

To investigate the outcomes of uveitis associated with Vogt-Koyanagi-Harada (VKH) disease in pediatric age group (aged 16 years and under).

METHODS

A retrospective review of patients with VKH disease.

RESULTS

Among the 244 patients identified, 38 (76 eyes) were children. Among them, five had insulin-dependent diabetes mellitus. 21 presented with initial-onset acute disease and 17 with chronic recurrent disease. The mean follow-up period was 59.1 months. At presentation, chronic recurrent disease was associated with more severe inflammation as indicated by the presence of mutton-fat keratic precipitates (p < .001), iris nodules (p = .005) and posterior synechiae (p < .001). During follow-up, the rate of complications was higher in children with chronic recurrent disease compared with initial-onset acute disease (p < .001). 92.4% of the eyes with initial-onset acute disease achieved a final visual acuity of ≥20/40 compared with 70.6% of the eyes with chronic recurrent disease (p = .013).

CONCLUSIONS

Chronic recurrent VKH disease in children is associated with worse outcomes.

Proprotein convertase furin is a driver and potential therapeutic target in proliferative diabetic retinopathy

BACKGROUND

Furin converts inactive proproteins into bioactive forms. By activating proinflammatory and proangiogenic factors, furin might play a role in pathophysiology of proliferative diabetic retinopathy (PDR).

METHODS

We studied vitreous samples from PDR and nondiabetic patients, epiretinal membranes from PDR patients, retinal microvascular endothelial cells (HRMECs), retinal Müller cells and rat retinas by ELISA, Western blot analysis, immunohistochemistry and immunofluorescence microscopy. We performed in vitro angiogenesis assays and assessed adherence of monocytes to HRMECs.

RESULTS

Furin levels were significantly increased in PDR vitreous samples. In epiretinal membranes, immunohistochemistry analysis revealed furin expression in monocytes/macrophages, vascular endothelial cells and myofibroblasts. Furin was significantly upregulated in diabetic rat retinas. Hypoxia and TNF-α induced significant upregulation of furin in Müller cells and HRMECs. Furin induced upregulation of phospho-ERK1/2, p65 subunit of NF-κB, ADAM17 and MCP-1 in cultured Müller cells and phospho-ERK1/2 in cultured HRMECs and induced HRMECs migration. Treatment of monocytes with furin significantly increased their adhesion to HRMECs. Intravitreal administration of furin in normal rats induced significant upregulation of p65 subunit of NF-κB, phospho-ERK1/2 and ICAM-1 in the retina. Inhibition of furin with dec-CMK significantly decreased levels of MCP-1 in culture medium of Müller cells and HRMECs and significantly attenuated TNF-α-induced upregulation of p65 subunit of NF-κB, ICAM-1 and VCAM-1 in HRMECs. Dec-CMK significantly decreased adherence of monocytes to HRMECs and TNF-α-induced upregulation of adherence of monocytes to HRMECs. Treatment of HRMECs with dec-CMK significantly attenuated migration of HRMECs.

CONCLUSIONS

Furin is a potential driver molecule of PDR-associated inflammation and angiogenesis.

Acute uveitic phase of Vogt-Koyanagi-Harada disease: optic nerve head swelling, ocular blood flow and retinal oxygen metabolism

OBJECTIVES

To investigate the association of optic nerve head (ONH) swelling in the acute uveitic phase of Vogt-Koyanagi-Harada (VKH) disease with blood flow velocity in the choroid and ONH and oxygen saturation and diameter of retinal vessels.

METHODS

In this prospective study, 25 patients (50 eyes) were studied. Thirteen patients (26 eyes) had ONH swelling and 12 patients (24 eyes) had no ONH swelling. Laser speckle flowgraphy (LSFG) and retinal oximetry measurements were performed at presentation.

RESULTS

In the ONH, mean blur rate (MBR)-vessel, representing blood flow velocity in retinal vessels, was significantly lower in the eyes affected by ONH swelling, while choroidal MBR was not significantly different. Eyes with ONH swelling had a significantly lower oxygen saturation in retinal venules, a significantly higher arteriovenous oxygen saturation difference and a significantly smaller calibre of retinal arterioles compared with eyes without ONH swelling. There were significant positive correlations between the MBR-vessel of the ONH and venular oxygen saturation and calibre of retinal arterioles. In addition, MBR-vessel of the ONH had a significant negative correlation with arteriovenous oxygen saturation difference.

CONCLUSIONS

The occurrence of ONH swelling in the acute uveitic phase of VKH disease is associated with lower retinal blood flow velocity and smaller calibre of retinal arterioles as well as lower oxygen saturation in retinal venules and higher arteriovenous difference in oxygen saturation.

Tissue Inhibitor of Metalloproteinase-3 Ameliorates Diabetes-Induced Retinal Inflammation

Purpose: Endogenous tissue inhibitor of matrix metalloproteinase-3 (TIMP-3) has powerful regulatory effects on inflammation and angiogenesis. In this study, we investigated the role of TIMP-3 in regulating inflammation in the diabetic retina.

Methods: Vitreous samples from patients with proliferative diabetic retinopathy (PDR) and non-diabetic patients were subjected to Western blot analysis. Streptozotocin-treated rats were used as a preclinical diabetic retinopathy (DR) model. Blood-retinal barrier (BRB) breakdown was assessed with fluorescein isothiocyanate (FITC)-conjugated dextran. Rat retinas, human retinal microvascular endothelial cells (HRMECs) and human retinal Müller glial cells were studied by Western blot analysis and ELISA. Adherence of human monocytes to HRMECs was assessed and in vitro angiogenesis assays were performed.

Results: Tissue inhibitor of matrix metalloproteinase-3 in vitreous samples was largely glycosylated. Intravitreal injection of TIMP-3 attenuated diabetes-induced BRB breakdown. This effect was associated with downregulation of diabetes-induced upregulation of the p65 subunit of NF-κB, intercellular adhesion molecule-1 (ICAM-1), and vascular endothelial growth factor (VEGF), whereas phospho-ERK1/2 levels were not altered. In Müller cell cultures, TIMP-3 significantly attenuated VEGF upregulation induced by high-glucose (HG), the hypoxia mimetic agent cobalt chloride (CoCl₂) and TNF-α and attenuated MCP-1 upregulation induced by CoCl₂ and TNF-α, but not by HG. TIMP-3 attenuated HG-induced upregulation of phospho-ERK1/2, caspase-3 and the mature form of ADAM17, but not the levels of the p65 subunit of NF-κB and the proform of ADAM17 in Müller cells. TIMP-3 significantly downregulated TNF-α-induced upregulation of ICAM-1 and VCAM-1 in HRMECs. Accordingly, TIMP-3 significantly decreased spontaneous and TNF-α- and VEGF-induced adherence of monocytes to HRMECs. Finally, TIMP-3 significantly attenuated VEGF-induced migration, chemotaxis and proliferation of HRMECs.

Conclusion:In vitro and in vivo data point to anti-inflammatory and anti-angiogenic effects of TIMP-3 and support further studies for its applications in the treatment of DR.

Effect of immunosuppressive therapy on ocular blood flow in initial-onset acute uveitis associated with Vogt-Koyanagi-Harada disease

PURPOSE

To investigate the effect of immunosuppressive therapy on blood flow and waveform parameters in the choroid and optic nerve head (ONH) in patients with initial-onset acute uveitis associated with Vogt-Koyanagi-Harada (VKH) disease.

METHODS

In this prospective study, 18 patients (36 eyes) were studied. Laser speckle flowgraphy was performed at baseline and at 4 weeks, 8 weeks and 12 weeks after treatment. We analysed longitudinal changes in mean blur rate (MBR), blow-out time, blow-out score (BOS), acceleration time index (ATI), flow acceleration index (FAI), resistivity index (RI) and blood flow fluctuation.

RESULTS

After immunosuppressive therapy, MBR, representing blood flow velocity, in the choroid and ONH significantly increased at each post-treatment time point compared to baseline values. Among the analysed pulse waveform parameters, BOS significantly increased, while RI and fluctuation significantly decreased. Increased BOS and decreased RI indicate decreased vascular resistance following treatment. There was a strong negative correlation between BOS and RI. Additionally, FAI increased in the choroid and ATI increased in ONH.

CONCLUSIONS

Immunosuppressive therapy in the acute uveitic phase of VKH disease improved inflammation-related impairment in choroidal and ONH blood flow.

CD146/Soluble CD146 Pathway Is a Novel Biomarker of Angiogenesis and Inflammation in Proliferative Diabetic Retinopathy

Purpose

Inflammation, angiogenesis and fibrosis are pathological hallmarks of proliferative diabetic retinopathy (PDR). The CD146/sCD146 pathway displays proinflammatory and proangiogenic properties. We investigated the role of this pathway in the pathophysiology of PDR.

Methods

Vitreous samples from 41 PDR and 27 nondiabetic patients, epiretinal fibrovascular membranes from 18 PDR patients, rat retinas, human retinal microvascular endothelial cells (HRMECs) and human retinal Müller glial cells were studied by ELISA, Western blot analysis, immunohistochemistry and immunofluorescence microscopy analysis. Blood-retinal barrier breakdown was assessed with fluorescein isothiocyanate-conjugated dextran.

Results

sCD146 and VEGF levels were significantly higher in vitreous samples from PDR patients than in nondiabetic patients. In epiretinal membranes, immunohistochemical analysis revealed CD146 expression in leukocytes, vascular endothelial cells and myofibroblasts. Significant positive correlations were detected between numbers of blood vessels expressing CD31, reflecting angiogenic activity of PDR, and numbers of blood vessels and stromal cells expressing CD146. Western blot analysis showed significant increase of CD146 in diabetic rat retinas. sCD146 induced upregulation of phospho-ERK1/2, NF-κB, VEGF and MMP-9 in Müller cells. The hypoxia mimetic agent cobalt chloride, VEGF and TNF-α induced upregulation of sCD146 in HRMECs. The MMP inhibitor ONO-4817 attenuated TNF-α-induced upregulation of sCD146 in HRMECs. Intravitreal administration of sCD146 in normal rats significantly increased retinal vascular permeability and induced significant upregulation of phospho-ERK1/2, intercellular adhesion molecule-1 and VEGF in the retina. sCD146 induced migration of HRMECs.

Conclusions

These results suggest that the CD146/sCD146 pathway is involved in the initiation and progression of PDR.

Effect of immunosuppressive therapy on oxygen saturation and diameter of retinal vessels in initial onset acute uveitis associated with Vogt-Koyanagi-Harada disease

PURPOSE

To demonstrate changes in oxygen saturation and calibre of retinal vessels in initial-onset acute uveitis associated with Vogt-Koyanagi-Harada (VKH) disease at baseline and during immunosuppressive therapy.

METHODS

In this prospective study, 22 patients (44 eyes) were studied. Retinal oximetry measurements were performed using the noninvasive spectrophotometric retinal oximeter (Oxymap T1) at baseline and at 1-3 months, 4-6 months, 5-7 months and more than 9 months after treatment.

RESULTS

At baseline, mean logarithm of the minimum angle of resolution (logMAR) best-corrected visual acuity (BCVA) was 1.12 ± 0.78 (Snellen equivalent, 20/265). Arteriolar and venular oxygen saturations were 108 ± 7% and 70 ± 9%, respectively and calibres of arterioles and venules were 12.1 ± 1.1 pixels and 16.9 ± 1.4 pixels, respectively. At 4-6 months of follow-up, logMAR BCVA was almost maximum (0.08 ± 0.1, Snellen equivalent 20/24; p < 0.001) and thereafter remained almost unchanged. After immunosuppressive therapy, arteriolar and venular oxygen saturation values continued to decrease up to >9 months of follow-up (92 ± 7% and 56 ± 10%, respectively; p < 0.001 for both arterioles and venules). Similarly, arteriolar and venular calibres continued to decrease up to >9 months of follow-up to 11.4 ± 0.9 pixels (p = 0.006) and 15.6 ± 1.3 pixels (p = 0.001), respectively.

CONCLUSIONS

Eyes with initial-onset acute uveitis associated with VKH disease have increased oxygen saturation and calibres of retinal vessels at baseline. Immunosuppressive therapy normalizes these changes and in a similar pattern improves BCVA.

Evaluation of Proteoforms of the Transmembrane Chemokines CXCL16 and CX3CL1, Their Receptors, and Their Processing Metalloproteinases ADAM10 and ADAM17 in Proliferative Diabetic Retinopathy

The transmembrane chemokine pathways CXCL16/CXCR6 and CX3CL1/CX3CR1 are strongly implicated in inflammation and angiogenesis. We investigated the involvement of these chemokine pathways and their processing metalloproteinases ADAM10 and ADAM17 in the pathophysiology of proliferative diabetic retinopathy (PDR). Vitreous samples from 32 PDR and 24 non-diabetic patients, epiretinal membranes from 18 patients with PDR, rat retinas, human retinal Müller glial cells and human retinal microvascular endothelial cells (HRMECs) were studied by enzyme-linked immunosorbent assay, immunohistochemistry and Western blot analysis. In vitro angiogenesis assays were performed and the adherence of leukocytes to CXCL16-stimulated HRMECs was assessed. CXCL16, CX3CL1, ADAM10, ADAM17 and vascular endothelial growth factor (VEGF) levels were significantly increased in vitreous samples from PDR patients. The levels of CXCL16 were 417-fold higher than those of CX3CL1 in PDR vitreous samples. Significant positive correlations were found between the levels of VEGF and the levels of CXCL16, CX3CL1, ADAM10 and ADAM17. Significant positive correlations were detected between the numbers of blood vessels expressing CD31, reflecting the angiogenic activity of PDR epiretinal membranes, and the numbers of blood vessels and stromal cells expressing CXCL16, CXCR6, ADAM10 and ADAM17. CXCL16 induced upregulation of phospho-ERK1/2, p65 subunit of NF-κB and VEGF in cultured Müller cells and tumor necrosis factor-α induced upregulation of soluble CXCL16 and ADAM17 in Müller cells. Treatment of HRMECs with CXCL16 resulted in increased expression of intercellular adhesion molecule-1 (ICAM-1) and increased leukocyte adhesion to HRMECs. CXCL16 induced HRMEC proliferation, formation of sprouts from HRMEC spheroids and phosphorylation of ERK1/2. Intravitreal administration of CXCL16 in normal rats induced significant upregulation of the p65 subunit of NF-κB, VEGF and ICAM-1 in the retina. Our findings suggest that the chemokine axis CXCL16/CXCR6 and the processing metalloproteinases ADAM10 and ADAM17 might serve a role in the initiation and progression of PDR.

Galectin-1 studies in proliferative diabetic retinopathy

PURPOSE

Galectin-1 regulates endothelial cell function and promotes angiogenesis. We investigated the hypothesis that galectin-1 may be involved in the pathogenesis of proliferative diabetic retinopathy (PDR).

METHODS

Vitreous samples from 36 PDR and 20 nondiabetic patients, epiretinal fibrovascular membranes from 13 patients with PDR, rat retinas and human retinal Müller glial cells were studied by enzyme-linked immunosorbent assay (ELISA), immunohistochemistry and Western blot analysis. In vitro angiogenesis assays were performed and the adherence of leukocytes to galectin-1-stimulated human retinal microvascular endothelial cells (HRMECs) was assessed.

RESULTS

The ELISA analysis revealed that galectin-1 and vascular endothelial growth factor (VEGF) levels were significantly higher in vitreous samples from PDR patients than in those from nondiabetics (p < 0.001 for both comparisons). A significant positive correlation was found between the levels of galectin-1 and VEGF (r = 0.354; p = 0.022). In epiretinal membranes, immunohistochemical analysis showed that galectin-1 was expressed in vascular endothelial cells expressing CD31, myofibroblasts expressing α-smooth muscle actin and leukocytes expressing CD45. The galectin-1 receptor neuropilin-1 was expressed on vascular endothelial cells. CD31 staining was used as a marker to assess microvessel density (MVD). Significant positive correlation was detected between MVD in epiretinal membranes and the number of blood vessels expressing galectin-1 (r = 0.848; p < 0.001). Western blot analysis demonstrated significant increase of galectin-1 protein in rat retinas after induction of diabetes. ELISA analysis revealed that hydrogen peroxide and cobalt chloride (CoCl₂ ) induced upregulation of galectin-1 in Müller cells. Treatment with galectin-1 induced upregulation of VEGF in Müller cells and increased leukocyte adhesion to HRMECs. The galectin-1 inhibitor OTX008 attenuated VEGF-induced HRMECs migration and CoCl₂ -induced upregulation of NF-κB, galectin-1 and VEGF in Müller cells.

CONCLUSIONS

These results suggest that galectin-1is involved in the pathogenesis of PDR.

The Proinflammatory and Proangiogenic Macrophage Migration Inhibitory Factor Is a Potential Regulator in Proliferative Diabetic Retinopathy

The macrophage migration inhibitory factor (MIF)/CD74 signaling pathway is strongly implicated in inflammation and angiogenesis. We investigated the expression of MIF and its receptor CD74 in proliferative diabetic retinopathy (PDR) to reveal a possible role of this pathway in the pathogenesis of PDR. Levels of MIF, soluble (s)CD74, soluble intercellular adhesion molecule-1 (sICAM-1) and vascular endothelial growth factor (VEGF) were significantly increased in the vitreous from patients with PDR compared to nondiabetic control samples. We detected significant positive correlations between the levels of MIF and the levels of sICAM-1 (r = 0.43; p = 0.001) and VEGF (r = 0.7; p < 0.001). Through immunohistochemical analysis of PDR epiretinal membranes, significant positive correlations were also found between microvessel density (CD31 expression) and the numbers of blood vessels expressing MIF (r = 0.56; p = 0.045) and stromal cells expressing MIF (r = 0.79; p = 0.001) and CD74 (r = 0.59; p = 0.045). Similar to VEGF, MIF was induced in Müller cells cultured under hypoxic conditions and MIF induced phosphorylation of ERK1/2 and VEGF production in Müller cells. Intravitreal administration of MIF in normal rats induced increased retinal vascular permeability and significant upregulation of phospho-ERK1/2, NF-κB, ICAM-1 and vascular cell adhesion molecule-1 expression in the retina. MIF induced migration and proliferation of human retinal microvascular endothelial cells. These results suggest that MIF/CD74 signaling is involved in PDR angiogenesis.

Incidence, Risk Factors and Surgical Outcomes of Cataract among Patients with Vogt-Koyanagi-Harada Disease

Purpose: To investigate risk factors and surgical outcomes of cataract in Vogt-Koyanagi-Harada (VKH) disease.Methods: Review of 187 patients (374 eyes).Results: At presentation, cataract was diagnosed in 56 (14.9%) eyes all had chronic recurrent VKH. During follow-up, cataract developed in additional 51 (13.6%) eyes. Fifteen (13.6%) of these had initial-onset acute VKH with anterior segment (AS) inflammation and 36 (19.4%) had chronic recurrent VKH. No patient with initial-onset acute VKH without AS inflammation developed cataract. Risk factors for cataract development during follow-up included female gender, keratic precipitates, anterior chamber reaction ≥2+, chronic recurrent VKH, posterior synechiae, iris nodules, glaucoma, glaucoma surgery, choroidal neovascular membrane, "sunset glow fundus" and chorioretinal atrophy. Thirty-two eyes underwent cataract extraction. Fourteen (43.8%) eyes achieved ≥20/40. Posterior segment complications of chronic recurrent VKH accounted for <20/40 outcome.Conclusions: Poor outcome after surgery is secondary to posterior segment complications of chronic recurrent VKH.

Expression of interleukin (IL)-10 family cytokines in aqueous humour of patients with specific endogenous uveitic entities: elevated levels of IL-19 in human leucocyte antigen-B27-associated uveitis

PURPOSE

Evidence exists that the interleukin (IL)-10 family of cytokines is involved in autoimmune diseases. The aim of this study was to analyse the levels of the IL-10 family cytokines IL-10, IL-19, IL-20, IL-22, IL-26, IL-28A and IL-29 in aqueous humour (AH) samples from patients with specific uveitic entities. In addition, we correlated their levels with the levels of the proinflammatory cytokines tumour necrosis factor-α (TNF-α) and IL-1β.

METHODS

Aqueous humour (AH) samples from patients with active uveitis associated with Behçet's disease (BD; n = 13), sarcoidosis (n = 8), human leucocyte antigen (HLA)-B27-related inflammation (n = 12), Vogt-Koyanagi-Harada (VKH) disease (n = 12) and control subjects (n = 9) were assayed with the use of a multiplex assay.

RESULTS

Of all the IL-10 family cytokines studied, only IL-19 levels were significantly higher in AH samples of patients (n = 45) than in controls (p = 0.022). When comparing the four individual disease groups to controls, IL-19 levels were only significantly higher in HLA-B27-associated uveitis (p < 0.001). IL-19 levels were significantly higher in patients with HLA-B27-associated uveitis than in patients with BD, sarcoidosis and VKH disease (p < 0.001; p = 0.002; p < 0.001, respectively). Significant correlations were found between AH levels of IL-19 and AH levels of TNF-α, (r = 0.3; p = 0.03) and IL-1β (r = 0.56; p < 0.001).

CONCLUSIONS

Among the IL-10 family cytokines analysed, IL-19 demonstrated the highest expression in endogenous uveitis, particularly in HLA-B27-associated uveitis. IL-19 thus might assist in the regulation of inflammation in HLA-B27-associated uveitis.

Local Cytokine Expression Profiling in Patients with Specific Autoimmune Uveitic Entities

Purpose: To evaluate expression of cytokines GM-CSF, IL-11, IL-12p40, IL-12p70, IL-27p28, IL-35, APRIL, BAFF, TWEAK, and LIGHT in uveitis.Methods: Aqueous humor samples from patients with active uveitis associated with Behçet's disease (BD), sarcoidosis, HLA-B27-related inflammation, and Vogt-Koyanagi-Harada (VKH) disease and control patients were assayed with a multiplex assay.Results: Comparing all patients to controls, GM-CSF, IL-11, IL-12p40, APRIL, and BAFF were significantly increased, whereas LIGHT was significantly decreased. IL-11 and BAFF were the most strongly upregulated, being elevated 19.7-fold and 14.1-fold, respectively, compared with controls. IL-11 was significantly highest in HLA-B27 uveitis. GM-CSF, IL-11, and IL-12p40 were significantly higher in nongranulomatous uveitis (BD and HLA-B27) than in granulomatous uveitis (sarcoidosis and VKH), whereas APRIL and TWEAK were significantly higher in granulomatous uveitis.Conclusions: IL-11-driven immune responses might be more potent in nongranulomatous uveitis, particularly in HLA-B27 uveitis. BAFF and APRIL might contribute to B cell-driven autoimmune response in uveitis.

Retinal vessel oxygen saturation is affected in uveitis associated with Vogt-Koyanagi-Harada disease

AIMS

To discover whether retinal vessel oxygen metabolism is affected in uveitis associated with Vogt-Koyanagi-Harada (VKH) disease.

METHODS

41 patients with VKH disease (82 eyes) and 12 healthy subjects (24 eyes) matched in age and gender were prospectively evaluated. Retinal oxygen saturation and vessel calibre were measured with a non-invasive spectrophotometric retinal oximeter (Oxymap T1).

RESULTS

In healthy controls, mean arteriolar oxygen saturation (%) was 93.8±5.9 and venular saturation was 60.1±5.8. In acute VKH uveitic phase associated with exudative retinal detachment (n=12), arteriolar and venular oxygen saturation values were 104.7±7.8 and 67.9±7.7, respectively, and both are significantly higher than the healthy group (p<0.001; p=0.001, respectively). In patients with VKH disease who recovered after immunosuppressive therapy and restored normal anatomy without 'sunset glow fundus' (n=13), oximetry values were 96.4±9.6 and 61.6±7.5, respectively, similar to healthy controls. In patients with 'sunset glow fundus' and chorioretinal atrophy (n=16), saturation levels were 88.6±7.8 and 50.0±13.1, respectively, significantly lower than healthy controls (p=0.02; p=0.003, respectively). These patients also had significantly smaller diameter of retinal arterioles and venules compared with controls (p=0.035; p=0.001, respectively).

CONCLUSIONS

Retinal oxygen metabolism is altered in uveitis associated with VKH disease. Oxygen saturation profile is abnormal in acute uveitic phase of the disease and returns to normal in those who recover with normal fundus appearance, but not in eyes that suffer permanent anatomical damage with 'sunset glow fundus' and chorioretinal atrophy. Retinal oximetry may be of value in evaluating vascular and metabolic aspects of posterior uveitis.

Differential CXC and CX3C Chemokine Expression Profiles in Aqueous Humor of Patients With Specific Endogenous Uveitic Entities

Purpose

To determine the levels of the neutrophil chemoattractants CXCL1, CXCL2, CXCL5, CXCL6, and CXCL8, the T helper 1 chemoattractants CXCL9, CXCL10 and CXCL11, the lymphoid chemokines CXCL12 and CXCL13 and the soluble form of the transmembrane chemokines CXCL16 and CX3CL1, in aqueous humor samples from patients with specific uveitic entities.

Methods

Aqueous humor samples from patients with active uveitis associated with Behçet's disease (n = 13), sarcoidosis (n = 8), HLA-B27-related inflammation (n = 12), Vogt-Koyanagi-Harada (VKH) disease (n = 12), and healthy controls (n = 9) were assayed with the use of a multiplex assay.

Results

All chemoattractant levels were significantly higher in all patients than in the controls. The levels of all neutrophil chemoattractants and CXCL10, CXCL16, and CX3CL1 were significantly higher in nongranulomatous uveitis (Behçet's disease and HLA-B27-associated uveitis) than in granulomatous uveitis (sarcoidosis and VKH disease), whereas the levels of the B cell chemoattractant CXCL13 were significantly higher in granulomatous uveitis than in nongranulomatous uveitis. CXCL13 levels were highest in the patients with VKH disease. CXCL9, CXCL11, and CXCL12 levels did not differ significantly.

Conclusions

Inflammation in nongranulomatous uveitis appears to be driven by neutrophils and T helper 1 lymphocytes, whereas B lymphocytes may contribute to the inflammatory process in granulomatous uveitis, particularly in VKH disease.

The CC chemokines CCL8, CCL13 and CCL20 are local inflammatory biomarkers of HLA-B27-associated uveitis

PURPOSE

To determine the concentrations of the CC chemokines CCL2, CCL7, CCL8, CCL11, CCL13, CCL20, CCL24 and CCL26 in aqueous humour (AH) samples from patients with specific uveitic entities.

METHODS

Aqueous humour samples from patients with active uveitis associated with Behçet's disease (BD) (n = 13), sarcoidosis (n = 8), HLA-B27-related inflammation (n = 12), Vogt-Koyanagi-Harada (VKH) disease (n = 12) and control patients (n = 9) were assayed with the use of a multiplex assay.

RESULTS

When considering all uveitis patients as one group, all chemokine levels except CCL2 were significantly increased compared to controls. CCL8, CCL13 and CCL20 were the most strongly upregulated, 48-fold, 118-fold and 173-fold, respectively, above control AH levels. CCL8 and CCL13 levels were significantly higher in HLA-B27-associated uveitis than in sarcoidosis and VKH disease. CCL20 levels were significantly higher in HLA-B27-associated uveitis than in BD, sarcoidosis and VKH disease. In addition, CCL20 levels were significantly higher in BD than in VKH disease. In HLA-B27-associated uveitis, CCL8, CCL13 and CCL20 were upregulated 111-fold, 255-fold and 465-fold, respectively, compared with controls. CCL8, CCL13 and CCL20 levels were significantly higher in nongranulomatous uveitis (BD and HLA-B27-associated uveitis) than in granulomatous uveitis (sarcoidosis and VKH disease).

CONCLUSION

Immune responses mediated by CCL8, CCL13 and CCL20 appear to be more potent in nongranulomatous uveitis, particularly in HLA-B27-associated uveitis.

Pediatric open-globe injury in a university-based tertiary hospital

BACKGROUND

To investigate epidemiology, etiology, and outcomes after repair of pediatric open-globe injury.

METHODS

We retrospectively reviewed medical records of patients ⩽18 years who underwent primary open-globe repair.

RESULTS

A total of 213 patients were identified. Male-female ratio was 1.44:1. Type of injury was penetration in 157 (74.4%) cases, rupture in 52 (24.4%) cases, and perforation in 2 (0.9%) cases. Knife injuries were the most common cause, affecting 38/196 (19.4%), followed by metallic object in 37/196 (18.9%) patients, glass in 26/196 (13.3%) patients, and pen or pencil in 24/196 (12.8%). Predictors of good visual outcome defined as (⩾20/40) were good initial visual acuity (⩾20/40; p < 0.0001), time from injury to arrival at the emergency room >24 h (p = 0.038), size of wound less than 10 mm (p < 0.0001), absence of iris prolapse (p < 0.0001), deep anterior chamber at presentation (p < 0.0001), absence of hyphema (p = 0.043), intact lens (p < 0.0001), and no retinal detachment during follow-up (p < 0.0001). A total of 27 (12.7%) cases were documented to have retinal detachment at any time during follow-up period. Predictors of retinal detachment were perforation and rupture (p < 0.0001), whereas penetration was not associated with development of retinal detachment, size of the wound ⩾10 mm (p < 0.0001), initial visual acuity ⩽20/200 (p < 0.0001), lens injury (p < 0.0001), and development of endophthalmitis (p < 0.027). Eight (3.7%) eyes had the clinical diagnosis of posttraumatic endophthalmitis.

CONCLUSIONS

The most common type of injury was penetration and the most common tool was knife. Visual outcome was affected by the initial presentation. Retinal detachment was a significant predictor of a worse final visual outcome.

Comparison of Goldmann Applanation, Noncontact Air Puff, and Tono-Pen XL Tonometry in Normal Controls versus Glaucoma Patients at a University Hospital in Riyadh, Saudi Arabia

PURPOSE:

The purpose of this study is to compare intraocular pressure (IOP) measured by the Goldmann applanation tonometer (GAT), the Tono-Pen XL (TPXL), and a noncontact airpuff tonometer (NCT) in glaucoma patients and normal controls.

METHODOLOGY:

In the current study, two groups of individuals were recruited; the first group included glaucoma patients (glaucoma group) while the second one was a glaucoma-free group. The IOP was measured through GAT, NCT, and TPXL for the same participants by three different physicians in both groups. Measurements through the three devices were compared statistically. Correlations between different methods of assessment were also assessed.

RESULTS:

In the glaucoma group, the mean IOP measured was 16.0 ± 5.5 mmHg (range, 6–40 mmHg) with GAT 20.5 ± 6.9 mmHg (range, 10–52 mmHg) with the TPXL, and 20.2 ± 6.5 mmHg (range, 8–50 mmHg) with the NCT. In the control group, the mean IOP was 14.0 ± 2.7 mmHg (range, 9–19 mmHg) with GAT, 17.3 ± 3.8 mmHg (range 6–30 mmHg) with the TPXL, and 17.9 ± 3.9 mHg (range 10–27 mmHg) with the NCT.

CONCLUSION:

IOP measurements were approved among the three devices with relatively higher readings using both NTC and TPXL. All three methods are required to address different situations that present in the daily clinical and surgical practice.

Efficacy and safety of using topical cyclosporine A for treatment of moderate to severe dry eye disease

Objective

To investigate and evaluate the efficacy and safety of topical cyclosporine A for treatment of moderate to severe dry eye disease.

Materials and methods

This is a prospective study of patients with moderate to severe dry eye syndrome were recruited. All cases were selected from patients attending the ophthalmic outpatient clinic of Research institute of ophthalmology. Eligible patients were at least 21 years of age with a confirmed diagnosis of keratoconjunctivitis sicca with or without Sjogren's syndrome refractory to conventional management.

The medication used in this study were unit dose vials of unpreserved cyclosporine A 0.05% used twice daily.

The protocol was composed of a 2-week washout phase, a 12-week treatment phase, and a 4-week post treatment phase. Patients were evaluated at weeks 4, 8, 12 during the treatment phase. During these visits patients were evaluated for changes from base line in Schirmer test, rose Bengal staining, superficial punctuate erosions, BUT, impression cytology, symptoms of ocular discomfort and visual acuity. After completion of the treatment phase, patients were also evaluated at post treatment week 4, during this visit patients were assessed for Schirmer test, rose Bengal staining, superficial punctuate erosion, BUT, impression cytology, symptoms of ocular discomfort and visual acuity.

Results

Thirty two cases in the mean age of 47 (12.9), range [20–67] years; four (13%) male and 28 (87%) female were recruited in the current study. Out of them, 12 (38%) cases had Sjogren syndrome. Visual acuity improved significantly (p = 0.012), BUT (p < 0.0001) for both eyes, Schirmer measurements (p < 0.0001 and p = 0.029 for OD and OS, respectively).

Conclusions

Cyclosporine A ophthalmic emulsion 0.05% has been demonstrated to be effective and safe in human clinical trials. It reduces signs and symptoms of dry eye disease, with the fact that its effect continued to occur significantly within the treatment periods as well as improvement of ocular condition kept on, actually more slowly towards stability, despite the drug has already stopped.

Matrix metalloproteinase-14 is a biomarker of angiogenic activity in proliferative diabetic retinopathy

Purpose

Matrix metalloproteinase-14 (MMP-14) is a transmembrane MMP that plays a critical role in promoting angiogenesis. We investigated the expression levels of MMP-14 and correlated the levels with clinical disease activity and with the levels of the angiogenic factors vascular endothelial growth factor (VEGF) and MMP-9 in proliferative diabetic retinopathy (PDR). To reinforce the findings at the functional level, we examined the expression of MMP-14 in the retinas of diabetic rats.

Methods

Vitreous samples from 34 patients with PDR and 18 nondiabetic patients and epiretinal membranes from 13 patients with PDR and the retinas of rats were studied with enzyme-linked immunosorbent assay, immunohistochemistry, western blotting, and real-time reverse transcription PCR (RT-PCR).

Results

The MMP-14, VEGF, and MMP-9 levels were statistically significantly higher in the vitreous samples from patients with PDR than in the samples from the nondiabetic controls (p<0.001 for all comparisons). The MMP-14 levels in patients with PDR with active neovascularization were statistically significantly higher than those in patients with inactive PDR (p<0.001). There were statistically significant positive correlations between levels of MMP-14 and levels of VEGF (r = 0.3; p = 0.032) and MMP-9 (r = 0.54; p<0.001). In the epiretinal membranes, MMP-14 was expressed in vascular endothelial cells, leukocytes, and myofibroblasts. Statistically significant positive correlations were detected between the numbers of blood vessels expressing CD31 and the numbers of blood vessels (r = 0.74; p = 0.004) and stromal cells (r = 0.72; p = 0.005) expressing MMP-14. Statistically significant increases of MMP-14 mRNA and protein were detected in rat retinas after induction of diabetes.

Conclusions

These results suggest that MMP-14 is involved in PDR angiogenesis.

Mycophenolate mofetil combined with systemic corticosteroids prevents progression to chronic recurrent inflammation and development of 'sunset glow fundus' in initial-onset acute uveitis associated with Vogt-Koyanagi-Harada disease

PURPOSE

To evaluate the effectiveness and safety of mycophenolate mofetil (MMF) as first-line therapy combined with systemic corticosteroids in initial-onset acute uveitis associated with Vogt-Koyanagi-Harada (VKH) disease.

METHODS

This prospective study included 38 patients (76 eyes). The main outcome measures were final visual acuity, corticosteroid-sparing effect, progression to chronic recurrent granulomatous uveitis and development of complications, particularly 'sunset glow fundus'.

RESULTS

The mean follow-up period was 37.0 ± 29.3 (range 9-120 months). Visual acuity of 20/20 was achieved by 93.4% of the eyes. Corticosteroid-sparing effect was achieved in all patients. The mean interval between starting treatment and tapering to 10 mg or less daily was 3.8 ± 1.3 months (range 3-7 months). Twenty-two patients (57.9%) discontinued treatment without relapse of inflammation. The mean time observed off of treatment was 28.1 ± 19.6 months (range 1-60 months). None of the eyes progressed to chronic recurrent granulomatous uveitis. The ocular complications encountered were glaucoma in two eyes (2.6%) and cataract in five eyes (6.6%). None of the eyes developed 'sunset glow fundus', and none of the patients developed any systemic adverse events associated with the treatment.

CONCLUSIONS

Use of MMF as first-line therapy combined with systemic corticosteroids in patients with initial-onset acute VKH disease prevents progression to chronic recurrent granulomatous inflammation and development of 'sunset glow fundus'.

Vitreous hemorrhage in pediatric age group

Purpose. To identify and study causes of vitreous hemorrhage (VH) in pediatric age group and to investigate factors predicting visual and anatomical outcomes. Procedure. A retrospective review of patients aged 16 years or less with the diagnosis of vitreous hemorrhage from January 2005 until December 2010. Results. A total number of 230 patients (240 eyes) were identified. Traumatic vitreous hemorrhage accounted for 82.5%. In cases of accidental trauma, final visual acuity of 20/200 was significantly associated with visual acuity of ≥20/200 at presentation and the absence of retinal detachment at last follow-up. Patients with nontraumatic vitreous hemorrhage were significantly younger with higher rates of enucleation/evisceration/exenteration and retinal detachment at last follow-up compared to traumatic cases. Conclusion. Trauma is the most common cause of VH in pediatric age group. In this group, initial visual acuity was the most important predictor for visual outcome, and the presence of retinal detachment is a negative predictor for final good visual outcome. The outcome is significantly worse in nontraumatic cases compared to traumatic cases.

Developing geostatistical space-time models to predict outpatient treatment burdens from incomplete national data

Basic health system data such as the number of patients utilising different health facilities and the types of illness for which they are being treated are critical for managing service provision. These data requirements are generally addressed with some form of national Health Management Information System (HMIS) which coordinates the routine collection and compilation of data from national health facilities. HMIS in most developing countries are characterised by widespread under-reporting. Here we present a method to adjust incomplete data to allow prediction of national outpatient treatment burdens. We demonstrate this method with the example of outpatient treatments for malaria within the Kenyan HMIS. Three alternative modelling frameworks were developed and tested in which space-time geostatistical prediction algorithms were used to predict the monthly tally of treatments for presumed malaria cases (MC) at facilities where such records were missing. Models were compared by a cross-validation exercise and the model found to most accurately predict MC incorporated available data on the total number of patients visiting each facility each month. A space-time stochastic simulation framework to accompany this model was developed and tested in order to provide estimates of both local and regional prediction uncertainty. The level of accuracy provided by the predictive model, and the accompanying estimates of uncertainty around the predictions, demonstrate how this tool can mitigate the uncertainties caused by missing data, substantially enhancing the utility of existing HMIS data to health-service decision-makers.

Access and barriers to measures targeted to prevent malaria in pregnancy in rural Kenya

Objectives

To evaluate barriers preventing pregnant women from using insecticide-treated nets (ITN) and intermittent presumptive treatment (IPT) with sulphadoxine-pyrimethamine (SP) 5 years after the launch of the national malaria strategy promoting these measures in Kenya.

Methods

All women aged 15–49 years were interviewed during a community survey in four districts between December 2006 and January 2007. Women pregnant in the last 12 months were asked about their age, parity, education, use of nets, ITN, antenatal care (ANC) services and sulphadoxine-pyrimethamine (SP) (overall and for IPT) during pregnancy. Homestead assets were recorded and used to develop a wealth index. Travel time to ANC clinics was computed using a geographic information system algorithm. Predictors of net and IPT use were defined using multivariate logistic regression.

Results

Overall 68% of pregnant women used a net; 52% used an ITN; 84% attended an ANC clinic at least once and 74% at least twice. Fifty-three percent of women took at least one dose of IPT-SP, however only 22% took two or more doses. Women from the least poor homesteads (OR = 2.53, 1.36–4.68) and those who used IPT services (OR = 1.73, 1.24–2.42) were more likely to sleep under any net. Women who used IPT were more likely to use ITNs (OR = 1.35, 1.03–1.77), while those who lived more than an hour from an ANC clinic were less likely (OR = 0.61, 0.46–0.81) to use ITN. Women with formal education (1.47, 1.01–2.17) and those who used ITN (OR: 1.68, 1.20–2.36) were more likely to have received at least one dose of IPT-SP.

Conclusion

Although the use of ITN had increased 10-fold and the use of IPT fourfold since last measured in 2001, coverage remains low. Provider practices in the delivery of protective measures against malaria must change, supported by community awareness campaigns on the importance of mothers’ use of IPT.

The limits and intensity of Plasmodium falciparum transmission: implications for malaria control and elimination worldwide

BACKGROUND

The efficient allocation of financial resources for malaria control using appropriate combinations of interventions requires accurate information on the geographic distribution of malaria risk. An evidence-based description of the global range of Plasmodium falciparum malaria and its endemicity has not been assembled in almost 40 y. This paper aims to define the global geographic distribution of P. falciparum malaria in 2007 and to provide a preliminary description of its transmission intensity within this range.

METHODS AND FINDINGS

The global spatial distribution of P. falciparum malaria was generated using nationally reported case-incidence data, medical intelligence, and biological rules of transmission exclusion, using temperature and aridity limits informed by the bionomics of dominant Anopheles vector species. A total of 4,278 spatially unique cross-sectional survey estimates of P. falciparum parasite rates were assembled. Extractions from a population surface showed that 2.37 billion people lived in areas at any risk of P. falciparum transmission in 2007. Globally, almost 1 billion people lived under unstable, or extremely low, malaria risk. Almost all P. falciparum parasite rates above 50% were reported in Africa in a latitude band consistent with the distribution of Anopheles gambiae s.s. Conditions of low parasite prevalence were also common in Africa, however. Outside of Africa, P. falciparum malaria prevalence is largely hypoendemic (less than 10%), with the median below 5% in the areas surveyed.

CONCLUSIONS

This new map is a plausible representation of the current extent of P. falciparum risk and the most contemporary summary of the population at risk of P. falciparum malaria within these limits. For 1 billion people at risk of unstable malaria transmission, elimination is epidemiologically feasible, and large areas of Africa are more amenable to control than appreciated previously. The release of this information in the public domain will help focus future resources for P. falciparum malaria control and elimination.

Information for decision making from imperfect national data: tracking major changes in health care use in Kenya using geostatistics

BACKGROUND

Most Ministries of Health across Africa invest substantial resources in some form of health management information system (HMIS) to coordinate the routine acquisition and compilation of monthly treatment and attendance records from health facilities nationwide. Despite the expense of these systems, poor data coverage means they are rarely, if ever, used to generate reliable evidence for decision makers. One critical weakness across Africa is the current lack of capacity to effectively monitor patterns of service use through time so that the impacts of changes in policy or service delivery can be evaluated. Here, we present a new approach that, for the first time, allows national changes in health service use during a time of major health policy change to be tracked reliably using imperfect data from a national HMIS.

METHODS

Monthly attendance records were obtained from the Kenyan HMIS for 1 271 government-run and 402 faith-based outpatient facilities nationwide between 1996 and 2004. A space-time geostatistical model was used to compensate for the large proportion of missing records caused by non-reporting health facilities, allowing robust estimation of monthly and annual use of services by outpatients during this period.

RESULTS

We were able to reconstruct robust time series of mean levels of outpatient utilisation of health facilities at the national level and for all six major provinces in Kenya. These plots revealed reliably for the first time a period of steady nationwide decline in the use of health facilities in Kenya between 1996 and 2002, followed by a dramatic increase from 2003. This pattern was consistent across different causes of attendance and was observed independently in each province.

CONCLUSION

The methodological approach presented can compensate for missing records in health information systems to provide robust estimates of national patterns of outpatient service use. This represents the first such use of HMIS data and contributes to the resurrection of these hugely expensive but underused systems as national monitoring tools. Applying this approach to Kenya has yielded output with immediate potential to enhance the capacity of decision makers in monitoring nationwide patterns of service use and assessing the impact of changes in health policy and service delivery.

The decline in paediatric malaria admissions on the coast of Kenya

Background

There is only limited information on the health impact of expanded coverage of malaria control and preventative strategies in Africa.

Methods

Paediatric admission data were assembled over 8.25 years from three District Hospitals; Kilifi, Msambweni and Malindi, situated along the Kenyan Coast. Trends in monthly malaria admissions between January 1999 and March 2007 were analysed using several time-series models that adjusted for monthly non-malaria admission rates and the seasonality and trends in rainfall.

Results

Since January 1999 paediatric malaria admissions have significantly declined at all hospitals. This trend was observed against a background of rising or constant non-malaria admissions and unaffected by long-term rainfall throughout the surveillance period. By March 2007 the estimated proportional decline in malaria cases was 63% in Kilifi, 53% in Kwale and 28% in Malindi. Time-series models strongly suggest that the observed decline in malaria admissions was a result of malaria-specific control efforts in the hospital catchment areas.

Conclusion

This study provides evidence of a changing disease burden on the Kenyan coast and that the most parsimonious explanation is an expansion in the coverage of interventions such as the use of insecticide-treated nets and the availability of anti-malarial medicines. While specific attribution to intervention coverage cannot be computed what is clear is that this area of Kenya is experiencing a malaria epidemiological transition.

Assembling a global database of malaria parasite prevalence for the Malaria Atlas Project

BACKGROUND

Open access to databases of information generated by the research community can synergize individual efforts and are epitomized by the genome mapping projects. Open source models for outputs of scientific research funded by tax-payers and charities are becoming the norm. This has yet to be extended to malaria epidemiology and control.

METHODS

The exhaustive searches and assembly process for a global database of malaria parasite prevalence as part of the Malaria Atlas Project (MAP) are described. The different data sources visited and how productive these were in terms of availability of parasite rate (PR) data are presented, followed by a description of the methods used to assemble a relational database and an associated geographic information system. The challenges facing spatial data assembly from varied sources are described in an effort to help inform similar future applications.

RESULTS

At the time of writing, the MAP database held 3,351 spatially independent PR estimates from community surveys conducted since 1985. These include 3,036 Plasmodium falciparum and 1,347 Plasmodium vivax estimates in 74 countries derived from 671 primary sources. More than half of these data represent malaria prevalence after the year 2000.

CONCLUSION

This database will help refine maps of the global spatial limits of malaria and be the foundation for the development of global malaria endemicity models as part of MAP. A widespread application of these maps is envisaged. The data compiled and the products generated by MAP are planned to be released in June 2009 to facilitate a more informed approach to global malaria control.

Improving imperfect data from health management information systems in Africa using space-time geostatistics

BACKGROUND

Reliable and timely information on disease-specific treatment burdens within a health system is critical for the planning and monitoring of service provision. Health management information systems (HMIS) exist to address this need at national scales across Africa but are failing to deliver adequate data because of widespread underreporting by health facilities. Faced with this inadequacy, vital public health decisions often rely on crudely adjusted regional and national estimates of treatment burdens.

METHODS AND FINDINGS

This study has taken the example of presumed malaria in outpatients within the largely incomplete Kenyan HMIS database and has defined a geostatistical modelling framework that can predict values for all data that are missing through space and time. The resulting complete set can then be used to define treatment burdens for presumed malaria at any level of spatial and temporal aggregation. Validation of the model has shown that these burdens are quantified to an acceptable level of accuracy at the district, provincial, and national scale.

CONCLUSIONS

The modelling framework presented here provides, to our knowledge for the first time, reliable information from imperfect HMIS data to support evidence-based decision-making at national and sub-national levels.

Creating spatially defined databases for equitable health service planning in low-income countries: the example of Kenya

Equity is an important criterion in evaluating health system performance. Developing a framework for equitable and effective resource allocation for health depends upon knowledge of service providers and their location in relation to the population they should serve. The last available map of health service providers in Kenya was developed in 1959. We have built a health service provider database from a variety of traditional government and opportunistic non-government sources and positioned spatially these facilities using global positioning systems, hand-drawn maps, topographical maps and other sources. Of 6674 identified service providers, 3355 (50%) were private sector, employer-provided or specialist facilities and only 39% were registered in the Kenyan Ministry of Health database during 2001. Of 3319 public service facilities supported by the Ministry of Health, missions, not-for-profit organizations and local authorities, 84% were registered on a Ministry of Health database and we were able to acquire co-ordinates for 92% of these. The ratio of public health services to population changed from 1:26,000 in 1959 to 1:9300 in 1999-2002. There were 82% of the population within 5 km of a public health facility and resident in 20% of the country. Our efforts to recreate a comprehensive, spatially defined list of health service providers has identified a number of weaknesses in existing national health management information systems, which with an increased commitment and minimal costs can be redressed. This will enable geographic information systems to exploit more fully facility-based morbidity data, population distribution and health access models to target resources and monitor the ability of health sector reforms to achieve equity in service provision.