Human ophthalmomyiasis caused by Oestrus ovis-first report from Croatia and review on cases from Mediterranean countries.

Oestrus ovis is the most common cause of human ophthalmomyiasis. So far, majority of ophthalmomyiasis cases have been reported from Mediterranean countries, but not from Croatia. In current study, we present first two cases of human ophthalmomyiasis in Croatia, caused by O. ovis larvae. Reviewing a PubMed database, additional 259 cases of human ophthalmomyiasis in countries of Mediterranean basin have been reported. A total of 260 (99.62%) cases had external, while 1 (0.38%) had internal form of ocular myiasis. In all cases, O. ovis larvae were identified as the causative agent. O. ovis infestation is usually reported in shepherds and farmers although there is a high prevalence of infection in urban areas as well. Various climatic factors influence O. ovis larvipositional activity. Air temperature is the most important factor affecting O. ovis larviposition, while humidity, wind speed, and time of the day play only a moderate role. Most common symptoms of ophthalmomyiasis are irritation and redness, and in more than half of cases infestation is multiple. Ophthalmomyiasis interna is eye-compromising condition. Since there is reduced awareness among patients and medical professionals, the real number of ophthalmomyiasis cases is probably significantly higher than published. Global warming predisposes future increase of O. ovis prevalence in humans, which emphasizes the need for mandatory reporting and surveillance of disease.

Monitoring of visual field over 6 months after active ocular toxoplasmosis.

PURPOSE: To prospectively report the perimetric defects during a 6-month follow-up (FU) in patients with initially active ocular toxoplasmosis (OT). METHODS: Twenty-four patients were studied, including 11 eyes with chorioretinal toxoplasmosis proven with a positive aqueous humor sample and 13 eyes with a biologically unproven, chorioretinal lesion. Automated 24-2 SITA-Standard visual fields were performed at baseline, at the first, and sixth months of FU. A composite clinical severity score was calculated from visual acuity (VA), severity of vitreitis, chorioretinal lesion size, location of the lesion in zone 1, the presence of an initial macular or papillary edema, and long-term scarring. This provided a relative cutoff level of severity. Nine eyes out of the 24 eyes were considered severe (3 unproven and 6 proven OT). RESULTS: Initial and final visual field parameters (mean deviation [MD] and pattern standard deviation [PSD]) were significantly correlated (r = 0.873; p < 0.001, and r = 0.890; p < 0.001, respectively). During FU, only foveal threshold [FT] was correlated with VA at baseline (r = 0.48; p = 0.01) and at the 6-month FU visit (r = 0.547; p = 0.004). The MD initial predictive value of clinical severity was 0.739 according to the ROC curve. At baseline, severe and nonsevere OT exhibited no significant difference in term of MD (p = 0.06) and PSD (p = 0.1). During the FU, taking into account all the data, MD, PSD, visual function index [VFI], and FT were associated with the severity of toxoplasmosis (p = 0.018, 0.05, 0.016, and 0.02, respectively): the unproven group had a faster recovery of MD during FU (p = 0.05). CONCLUSION: Visual field parameters better reflected the chorioretinal destruction related to the toxoplasmosis lesion and the functional repercussions than VA alone. Interestingly, MD at presentation could be a discriminating factor of severity in active OT, and each visual field parameter follow-up could be a support to manage patients with active OT, especially in the severe group.

Characterisation of ocular involvement in an experimental model of neuroschistosomiasis mansoni.

The Global Burden of Disease Study 2010 listed schistosomiasis among the leading 100 causes of death in Brazil, responsible for 3.6% of the estimated total of deaths globally. Eye and adnexa are very rarely affected by schistosomiasis mansoni, with limited documentation of ocular pathology in this setting. This short communication reports ocular histolopathological findings in a murine model of neuroschistosomiasis mansoni. Lesions were found in the bulbar conjunctiva, lacrimal gland, choroid and corneoscleral limbus.

Diffuse Unilateral Subacute Neuroretinitis (DUSN).

Diffuse unilateral subacute neuroretinitis (DUSN) is caused by a subretinal live and mobile nematode. Acute phase: Patients usually present with severe pain, decreased vision, vitritis/papillitis, and tracks of grayish-white lesions-and a live nematode. Late phase: Arterial narrowing, optic atrophy, diffuse disruption of the retinal pigment epithelium (RPE), with severe visual loss.

The eye fluke Tylodelphys clavata affects prey detection and intraspecific competition of European perch (Perca fluviatilis).

Parasites that occupy the eyes of fish have the potential to affect visual perception and consequently alter the host's behaviour, as these organs provide information about their surroundings. In an experimental study, the feeding behaviour of European perch (Perca fluviatilis) infested with the eye fluke Tylodelphys clavata was examined. The results showed that an individual's ability to identify and approach food items was negatively affected by the infestation intensity of T. clavata. Additionally, the foraging success of an individual was reduced in competition with another, less heavily infested conspecific, when the same food resource was exploited. These alterations in the ability to locate food may have important consequences on the feeding strategy of the fish. Furthermore, the impaired feeding capability caused by T. clavata may also increase the predation risk as heavily infested fish need to spend more time foraging to attain a rate of food intake equivalent to less infested conspecifics.

The Impact of Topical Corticosteroids Used in Conjunction with Antiamoebic Therapy on the Outcome of Acanthamoeba Keratitis.

PURPOSE: To examine the impact of topical corticosteroid use after the start of antiamoebic therapy (AAT) on the outcomes of Acanthamoeba keratitis (AK) therapy. DESIGN: Cohort study. PARTICIPANTS: A total of 196 patients diagnosed with AK at Moorfields Eye Hospital, London, between January 1991 and April 2012. In 13 patients with bilateral AK, 1 eye was randomly excluded from analysis. METHODS: Patient demographics and clinical examination findings were collected both at the start of AAT and subsequently at the time that topical corticosteroid therapy was initiated. Preliminary a priori investigations were used to identify effect modifiers/confounders and extreme associations requiring consideration in multivariate regression modeling. A multivariable logistic model, optimized for assessment of corticosteroid use after the start of AAT, was used to estimate the odds ratios (ORs) of a suboptimal outcome. MAIN OUTCOME MEASURES: Suboptimal outcome was defined as final visual acuity ≤20/80, corneal perforation, or the need for keratoplasty. RESULTS: In multivariable analysis, restricted to 129 eyes (1 eye per patient) free of scleritis and hypopyon at the start of AAT, topical corticosteroids were not associated with worse outcomes (OR, 1.08; 95% confidence interval [CI], 0.39-3.03), even when corticosteroids had been used before the start of AAT. Risk factors significantly associated with worse outcomes were topical corticosteroid use before the start of AAT (OR, 3.85; 95% CI, 1.35-11.03), a corneal ring infiltrate (together with at least 1 other feature of AK) present at the start of AAT (OR, 5.89; 95% CI, 1.17-29.67), and age ≥33 years at the start of AAT (OR, 4.02; 95% CI, 1.46-11.06). CONCLUSIONS: Many corneal specialists currently are uncertain about the risk benefit associated with the use of topical corticosteroids for the management of inflammatory complications of AK. The evidence from this study gives clinicians and patients reassurance that the potential benefits of topical corticosteroid therapy, for treating pain and discomfort, are not associated with worse outcomes when initiated after starting modern AAT. Other potential benefits, in terms of resolution of inflammatory complications, will not be demonstrated without a carefully designed randomized clinical trial.

Clinical Characteristics of Pediatric Patients with Ocular Toxocariasis in China.

OBJECTIVE: The aim of the study was to analyze the clinical characteristics of pediatric patients with ocular toxocariasis. METHODS: Ocular toxocariasis was diagnosed and treated in 46 children from Shanghai and surrounding provinces. The diagnosis of ocular toxocariasis was confirmed immunologically by performing an enzyme-linked immunosorbent assay on serum and/or intraocular fluid. All pediatric patients and their guardians completed a questionnaire concerning their cases and living habits. RESULTS: The mean age of onset was 6 ± 3 years. Most children (85%) resided in rural areas, and 91% of the children had contact with adult dogs or puppies. At the first visit, visual acuity (VA) was <20/200 in 36 cases, and we detected peripheral granuloma in 36 patients. In our study, the most common signs were vitritis, vitreous strands, and tractional retinal detachment. The Optomap 200Tx device detected granuloma with an 85% sensitivity, which is much higher than that of other techniques. We treated 40 cases (87%) with topical corticosteroids, while 28 patients (61%) were treated with systemic corticosteroids. Only 18 children (39%) required surgical intervention. All patients were examined and treated by the same ophthalmologists. CONCLUSIONS: Preschool children in China are more often affected by toxocariasis compared with other age groups. The most common signs included unilateral granuloma and ocular inflammation. In our study, clinical manifestations were severe and complicated. At the first visit, VA was <20/200 in most patients. Ocular toxocariasis was diagnosed on the basis of clinical signs and symptoms; the diagnosis was confirmed by immunological testing. Techniques using the Optomap 200Tx device can facilitate the early detection and lead to better visual prognosis.

Structural and functional retinal changes in eyes with DUSN.

PURPOSE: To report novel spectral domain optical coherence tomography and electrophysiologic findings in diffuse unilateral subacute neuroretinitis. METHODS: Six patients with a diagnosis of diffuse unilateral subacute neuroretinitis were retrospectively ascertained. All patients had received oral treatment with albendazole; resolution of the inflammatory lesions without subsequent relapse was noted. Spectral domain optical coherence tomography was performed using a Spectralis HRA OCT (Heidelberg Engineering). The inner and outer retinal volumes were calculated for the macular area. The contralateral eyes acted as controls. All six patients underwent standardized full-field electroretinography and pattern electroretinography. Some had multifocal electroretinography. RESULTS: Inner retinal volume significantly differed between affected and control eyes (P < 0.02), but there was no significant difference in outer retinal volume. Electroretinography data showed a mixed pattern of inner and outer retinal dysfunction, with inner retinal dysfunction being greater; reduction in b:a ratio of the scotopic bright flash electroretinography was a consistent observation in those patients (5/6) with generalized retinal dysfunction. Two patients showed definite photoreceptor involvement, with probable involvement in a third. Of the four patients in whom serial data are available, there was definite evidence of progressive inner and outer retinal dysfunction in one patient, with inner retinal dysfunction being greater, and probably in a second patient. CONCLUSION: The data provide anatomical and functional evidence of both inner and outer retinal dysfunction in diffuse unilateral subacute neuroretinitis, even though the worm is usually assumed to be located in the subretinal space. The mechanism is unclear.

Behavioral changes caused by Austrodiplostomum spp. in Hoplias malabaricus from the São Francisco River, Brazil.

Traira (Hoplias malabaricus) is a neotropical fish that is widely distributed in freshwater environments in South America. In the present study, we documented the occurrence of metacercariae of Austrodiplostomum spp. (Diplostomidae) in the eyes and cranial cavity of H. malabaricus and described parasite-induced behavioral changes in the host. The fish were collected from the upper São Francisco River, in the Serra da Canastra mountain range, Minas Gerais, transported alive to the laboratory, observed for 2 weeks, and subsequently examined for parasites. Of the 35 fish examined, 28 (80 %) had free metacercariae in the vitreous humor (mean intensity=95.4; mean abundance=76.3), and 24 (68.57 %) had free metacercariae in the cranial cavity, mainly concentrated below the floor of the brain, at the height of the ophthalmic lobe (mean intensity=12.91; mean abundance=8.85). Specimens of H. malabaricus with a high intensity of infection in the brain displayed changes in swimming behavior.

Impact of Acanthamoeba Keratitis on the Vision-Related Quality of Life of Contact Lens Wearers.

PURPOSE: The aim of this study was to determine the impact of Acanthamoeba keratitis (AK) caused by contact lens (CL) use on vision-related quality of life (VRQOL) and the sociodemographic factors and disease outcome associated with VRQOL. METHODS: Sixty-one CL-associated AK cases and 59 asymptomatic CL wearers (mean age ±SD 39.4 ± 16.5 vs. 45.5 ± 15.2 yrs, P = 0.04) were recruited from Moorfields Eye Hospital and Institute for Optometry, London. AK cases were surveyed during active disease and were stratified into "poor" and "good" outcomes based on clinical features. VRQOL was measured using Rasch-transformed scores from the Emotional, Mobility, and Reading domains of the 32-item Impact of Visual Impairment questionnaire. AK cases were compared with controls and "poor" outcomes compared with "good" with multivariable linear regression. Multivariable linear regression models were also used to identify the sociodemographic factors and disease outcome associated with VRQOL. RESULTS: AK was associated with significant and substantial reductions in all 3 evaluated domains of VRQOL (Reading -59.6%, Mobility -59.8%, and Emotional -66.2%) compared with controls, independent of sociodemographic factors. Patients with AK who experienced poor outcomes, those who were of British White race (compared with all other races) and female, had lower VRQOL scores across all domains. Patients with AK with lower incomes scored worse on Reading and Mobility domains, whereas those with lower education had poorer Emotional scores. CONCLUSIONS: AK has a considerable detrimental impact on VRQOL. Clinicians should consider the importance of referring patients with AK for rehabilitative support and counseling as part of active disease management.

Extensive Chorio-retinal Damage Due to Dirofilaria Repens- Report of a Case.

Purpose: To report a case of ocular dirofilariasis causing extensive chorio-retinal damage.Method: Surgical removal of the worm and identification of the same by microscopic examinationand polymerase chain reaction.Results: The worm was identified as Dirofilaria repens.Conclusion: Ocular dirofilariasis is an arthropod borne parasitic infestation affecting the subconjunctival tissue and anterior chamber. Vitreous involvement in Dirofilaria is very rare. Dirofilaria repens can cause extensive chorio-retinal damage resembling diffuse unilateralsubacute neuroretinitis.

Clinical Features of Toxocara-Seropositive Optic Neuritis in Korea.

Purpose: This study was undertaken to analyze the characteristics of optic neuritis in Korean patients seropositive for Toxocara. Methods: We retrospectively reviewed data from patients diagnosed with optic neuritis and followed up for at least one month between 2012 and 2016. Patients were grouped according to Toxocara serological testing outcomes (positive or negative) and clinical characteristics were compared. Results: The seropositive and seronegative groups comprised 13 and 12 patients, respectively. The seropositive patients were older (56.8 years versus 34.5 years), reported ocular pain less frequently (30.8% versus 91.7%), and showed more frequent asymmetric optic disc swelling (72.7% versus 22.2%). During follow-up, visual acuity of all seronegative patients improved to 20/40 or better, compared with 38.5% of the seropositive group. Conclusion: Atypical features such as painless, older age, or asymmetric disc swelling in optic neuritis may be related to seropositivity for Toxocara, suggesting the possibility of undiagnosed Toxocara optic neuropathy.

Experimental toxocariosis in BALB/c mice: effect of the inoculation dose on brain and eye involvement.

Ocular toxocarosis (OT) is a well-established disease. However, our understanding of the migratory route, time and circumstances that produce ocular invasion are not clear. To improve our knowledge of factors related to ocular invasion, BALB/c mice were inoculated with simple doses (SD) of 6, 12, 50, 100, 200 and 1000 embryonated eggs (EE) and multiple doses (MD) of 200 and 1000 EE. Brains and eyes were studied for the presence of larvae in animals sacrificed on days 3, 5, 7, 9, 11, 13, 15, 17, 19, 40, 80 and 120 in SD and on days 28, 30, 32, 34, 36, 38, 40, 42, 46, 87 and 127 in MD. The humoral immune responses were studied by ELISA using excretory-secretory antigen. Due to the considerable number of days tested, results showed are based on one set of experiments. However, each point studied represents the result obtained from a group of five mice. We have shown that the eye involvement with Toxocara canis larvae is a phenomenon mainly produced once larvae have reached the brain. There is a direct relationship between the parasitic load and the number of ocular larvae. Moreover, the arrival of larvae to the eye is an independent event, unrelated to the kind of administered dose (SD, MD), although the number of the brain larvae was higher in the cases of MD. High levels of specific antibodies were observed but they did not prevent the arrival of the larvae to the brain and the eye.

Malarial retinopathy: a newly established diagnostic sign in severe malaria.

Severe malaria is commonly misdiagnosed in Africa, leading to a failure to treat other life-threatening illnesses. In malaria-endemic areas, parasitemia does not ensure a diagnosis of severe malaria because parasitemia can be incidental to other concurrent disease. The detection of malarial retinopathy is a candidate diagnostic test for cerebral malaria. Malarial retinopathy consists of a set of retinal abnormalities that is unique to severe malaria and common in children with cerebral malaria. Its presence and severity are related to risk of death and length of coma in survivors. A large, prospective autopsy study of children dying with cerebral malaria in Malawi found that malarial retinopathy was better than any other clinical or laboratory feature in distinguishing malarial from non-malarial coma. However, visualization has to date relied on specialist examination techniques. Further studies are planned to evaluate the usefulness of funduscopy by general clinicians in a variety of settings across Africa. Studies of the retina and retinal blood vessels provide an unparalleled opportunity to visualize an infected microvasculature and its effect on neural tissue in vivo. This report reviews current knowledge of malarial retinopathy, including its use as a diagnostic test in the comatose child, and its value as a tool for research into the pathophysiology of cerebral malaria.

Ocular Toxocariasis: Clinical Features and Long-term Visual Outcomes in Adult Patients.

PURPOSE: To investigate clinical characteristics and treatment outcomes of proven ocular toxocariasis (OT) in adult patients. DESIGN: Retrospective, consecutive, interventional case series. METHODS: setting: Institutional. STUDY POPULATION: Consecutive OT patients with positive serum serology and positive western blot (WB) on ocular sample. OBSERVATION PROCEDURES: Clinical features, optical coherence tomography (OCT), and treatment outcomes. MAIN OUTCOME MEASURES: Best-corrected visual acuity (BCVA) and OCT central foveal thickness (CFT). RESULTS: Fourteen patients were included between 2011 and 2013. Mean age at diagnosis was 45.6 years. Mean duration between the first symptoms and diagnosis was 15.1 months. Uveitis was unilateral in all cases and all patients displayed vitreous inflammation. The main baseline findings were presence of ≥1 peripheral granulomas (57.1%), vasculitis (57.1%), vitreoretinal traction (57.1%), and chronic macular edema (ME) (71.4%). Delayed diagnosis (>8 months) seemed to be associated with higher rate of ME. All patients received albendazole. Systemic (n = 5) and/or local corticosteroids (CS) (n = 7) were administered in case of ME and/or posterior segment inflammation. Vitrectomy was performed when vitreous inflammation was severe and persistent despite CS or in case of threatening traction or visually significant epimacular membrane (28.6%). Overall, this regimen allowed significant decrease of CFT (P = .01). In the vitrectomy subgroup, mean BCVA increased (P = .01) and CFT decreased (P = .017). CONCLUSION: While some features such as granuloma are typical signs of OT, atypical features can delay the diagnosis. In doubtful situations, WB on ocular samples seems to be more specific than serum antibodies alone. ME seems to be a common complication of longstanding OT in the adult.

Photographic and angiographic characterization of the retina of Kenyan children with severe malaria.

OBJECTIVE: To investigate retinal lesions in children with severe falciparum malaria. METHODS: Color photography and fluorescein angiography were performed in consecutive children admitted to a pediatric high-dependency unit in Kenya during 1 malaria season. The presence and category of retinal lesion was compared with disease severity, clinical outcome, anemia, lactic acidosis, and parasite count. RESULTS: Twenty-six patients with cerebral malaria and 14 patients who were prostrate were studied. Thirty-one of the patients had clinical features of ocular disease, including round, flame-shaped, and white-centered hemorrhages; peripheral and foveal retinal opacification; peripheral vascular occlusion; venous dilation; disc edema with hyperemia; and arterial pulsatility. Of 8 patients with retinal opacification, only 2 showed small, infrequent zones of capillary nonperfusion on fluorescein angiography; the leakage of dye at sites of opacification was not seen. Retinal opacification was significantly associated with a higher parasite count (P < .02). White-centered hemorrhages were significantly associated with a higher parasite count (P < .05), severe disease (p < .05), and severe anemia (P < .02). CONCLUSIONS: The blood-retina barrier and retinal vascular flow remain substantially normal despite widespread pathological features. Retinal features in children with severe malaria are consistent with cellular hypoxia, nutritional deficiency, or both rather than with vascular occlusion; they support the concept of metabolic steal by parasites.

Prognostic significance and course of retinopathy in children with severe malaria.

OBJECTIVES: To relate retinal findings in children treated for severe malaria to disease outcome and to determine the course of changes in the fundus. METHODS: A prospective study of children with cerebral malaria (CM) and severe malarial anemia admitted to the Malaria Research Project, Blantyre, Malawi, during 2 malaria seasons. Indirect and direct ophthalmoscopy were performed on admission and daily, subject to the patient's cooperation. RESULTS: Three hundred twenty-six patients (91%) with complicated malaria were recruited. Two hundred seventy-eight patients had CM and of these 170 (61%) had some degree of retinopathy; 25 (53%) of 47 with severe malarial anemia had retinopathy. In CM, retinopathy was associated with subsequent death (relative risk, 3.7; 95% confidence interval, 1.6-8.5) and papilledema conferred the highest risk (relative risk, 4.5; 95% confidence interval, 2.7-7.6). Increasing severity of retinal signs was related to increasing risk of a fatal outcome (P<.05), independent of papilledema. In survivors, retinal signs were associated with prolonged time to recover consciousness (P<.001). Patients with severe malarial anemia had better outcomes and less severe retinopathy than those with CM. In 116 patients with CM, fundi were followed up longitudinally during admission and in 27 patients after hospital discharge. A large increase in retinal hemorrhages was associated with death (P =.02). Retinal signs resolved over 1 to 4 weeks without retinal sequelae. CONCLUSIONS: In childhood CM, severity of retinopathy is related to prolonged coma and death. Our results support the hypothesis that retinal signs in CM are related to cerebral pathophysiology.

Multifocal electroretinography response after laser photocoagulation of a subretinal nematode.

PURPOSE: To describe multifocal electroretinography findings before and after laser photocoagulation of a subretinal nematode in diffuse unilateral subacute neuroretinitis. METHOD: Observational case report. A 45-year-old woman with left eye inflammation, subretinal tracts superior and temporal to the fovea, and a subretinal coiled mobile parasite was treated with laser photocoagulation to destroy the nematode. Multifocal electroretinography was performed before and after laser photocoagulation. RESULTS: In the left eye, multifocal electroretinography before treatment showed decreased foveal response density and increased parafoveal and perifoveal waveform amplitudes. Two months after laser photocoagulation, multifocal electroretinography showed full recovery of normal findings and the visual acuity remained 20/20. CONCLUSION: Multifocal electroretinography appears to be useful in evaluating the retinal findings after photocoagulation of a parasite associated with diffuse unilateral subacute neuroretinitis.

Ocular angiostrongyliasis without meningitis symptoms in Okinawa, Japan.

A 62-year-old female farmer presented with retinal detachment in her left eye, and an Angiostrongylus cantonensis worm was recovered by vitreous surgery. The case did not show typical clinical symptoms indicating meningitis, although the patient complained of a mild headache, a low-grade fever, and slight ataxia. The symptoms were treated as influenza before the onset of the retinal detachment. The present case is the first confirmed of ocular angiostrongyliasis in Japan.