Acute acquired toxoplasmosis: clinical-laboratorial aspects and ophthalmologic evaluation in a cohort of immunocompetent patients

Most cases of acute acquired toxoplasmosis (AAT) are oligosymptomatic and self-limited. Therefore, these infections rarely indicate treatment. Prospective studies of AAT patients are rare in the medical literature. The frequency of systemic manifestations has not been sufficiently studied. In order to search for risks factors for systemic and ocular involvement, 37 patients were submitted to a diagnostic investigative protocol. The most frequent findings were lymph node enlargement (94.6%), asthenia (86.5%), headache (70.3%), fever (67.6%) and weight loss (62.2%). Hepatomegaly and/or splenomegaly were present in 21.6% of cases (8/37). Liver transaminases were elevated in 11 patients (29.7%) and lactic dehydrogenase in 17 patients (45.9%). Anaemia was found in four patients (10.8%), leucopoenia in six patients (16.2%), lymphocytosis in 14 patients (37.8%) and thrombocytopenia in one patient (2.7%). Fundoscopic examination revealed retinochoroiditis in four patients (10.8%). No statistical association was found between any one morbidity and retinochoroiditis. Nevertheless, a significant association was found between the presence of more than eight morbidity features at evaluation and long-lasting disease. An ideal diagnostic protocol for AAT would include evidence of systemic involvement. Such a protocol could be used when planning treatment.

Toxoplasma gondii in the peripheral blood of patients with acute and chronic toxoplasmosis

Background and aims Toxoplasmic retinochoroiditis may recur months or years after the primary infection. Rupture of dormant cysts in the retina is the accepted hypothesis to explain recurrence. Here, the authors present evidence supporting the presence of Toxoplasma gondii in the peripheral blood of immunocompetent patients. Methods Direct observation by light microscopy and by immunofluorescence assay was performed, and results were confirmed by PCR amplification of parasite DNA. Results The authors studied 20 patients from Erechim, Brazil, including acute infected patients, patients with recurrent active toxoplasmic retinochoroiditis, patients with old toxoplasmic retinal scars, and patients with circulating IgG antibodies against T gondii and absence of ocular lesions. Blood samples were analysed, and T gondii was found in the blood of acutely and chronically infected patients regardless of toxoplasmic retinochoroiditis. Conclusions The results indicate that the parasite may circulate in the blood of immunocompetent individuals and that parasitaemia could be associated with the reactivation of the ocular disease.

Estudo da frequência e perfil epidêmico-sorológico da toxoplasmose ocular em pacientes atendidos no ambulatório de oftalmologia do hospital universitário onofre lopes no município de Natal, Rio Grande do Norte

Toxoplasmosis, provoked by the intracellular parasite Toxoplasma gondii, is one of the most prevalent parasitoses in the world. In humans, transmission occurs by three evolutionary forms of the parasite: oocysts, tissue cysts and tachyzoites. Wild and domestic felines are definitive hosts. The ocular form of toxoplasmosis can be of congenital origin with early or late clinical manifestations, or acquired after birth. T. gondii is considered the main culprit for most cases of infectious uveitis. This study aimed at assessing ocular toxoplasmosis, relating it to factors associated to the patient s lifestyle and describing the epidemic-serological and clinical profile of affected individuals. A cross-sectional study was conducted with a population of 159 patients. Univariate analysis (odds ratio) was used to evaluate the data, with a confidence interval of 95% and p-value < 0.05. A prevalence of 4% of ocular toxoplasmosis was observed in the population of patients treated at an ophthalmological clinic. Of patients directly examined by immunoenzymatic assay (MEIA-AxSYM®- Microparticle Enzyme Immune Assay), considering only uveitis, a frequency of anti-T. gondii of 73%, most of whom exhibited titulation between 40-99 UI IgG/mL. With respect to location of ocular lesions, bilaterality was observed in 57% of patients assessed by the ophthalmoscopy technique. When compared with the results of an active search of medical records, a similarity in ocular toxoplasmosis (74%) and bilateral lesion location (55%) was observed. Type I lesion was the most frequent type observed, with intraocular disposition in the macula. An epidemiological survey revealed that direct contact with cats; consuming raw or poorly cooked meat and direct contact with the soil were significantly associated with greater likelihood of acquiring ocular toxoplasmosis. Sample characterization in relation to age range was significant for patients between 31 and 40 years [χ², chi-square test (p = 0.04)], but population traits such as schooling, sanitary district, and monthly income were not significant. Results confirm that ocular toxoplasmosis is widely distributed in the metropolitan area of Natal, Brazil, with significant prevalence of ocular lesions provoked by T.gondii. It is suggested that sanitary authorities exert greater control in order to minimize the risk of toxoplasmic infection, mainly in pregnant women.

Reabilitação estética por meio de prótese ocular a base de PMMA: relato de caso

Eye loss results on facial asymmetry compromising its aesthetics. Ocular prostheses are important to re-establish aesthetics; protect the anophthalmic cavity; recover function such as the redirection of lachrymatory liquid; and reintegrate the patient to society. The aim of this study was to describe a case report, demonstrating clinical and laboratorial procedures for confection of ocular prostheses and highlighting their advantages. A female patient was afflicted by toxoplasmosis, which led to the loss of her eye. An eye visceration was performed. The patient reported no previous use of ocular prosthesis. A PMMA ocular prosthesis was manufactured restoring patient’s aesthetic and facial contour. The patient was satisfied with the treatment. Therefore the present study has shown that PMMA ocular prosthesis is able to restore facial aesthetics and can be a safe and satisfactory alternative for patients that have lost their eyes due to toxoplasmosis.

Birth prevalence and characteristics of congenital toxoplasmosis in Sergipe, North-east Brazil

Objectives To estimate, by neonatal screening, the birth prevalence of congenital toxoplasmosis among live-born infants in Sergipe state, Brazil, and to investigate the clinical features of affected infants. Methods Dried blood spot specimens obtained from 15 204 neonates were assayed for the presence of anti-T. gondii IgM antibodies. Duplicate retesting was done in infants with positive and borderline results. Confirmatory testing in peripheral blood samples consisted of testing for anti-T. gondii IgG and IgM in infants and mothers. Those with possible congenital toxoplasmosis were evaluated and followed up to a median age of 20 months. Congenital infection was confirmed in the presence of persisting anti-T. gondii IgG antibodies beyond 12 months of age. All infants with confirmed infection were treated with pyrimethamine, sulfadiazine and folinic acid for 1 year. Results Fifty-three infants had detectable IgM in dried blood spot specimens. Confirmatory testing was reactive in 39/50, of which, 38 completed follow-up. Six of 15 204 newborns were diagnosed with congenital toxoplasmosis, resulting in an estimated birth prevalence of four per 10 000 [CI 95% 1.48.0]. Four infants (67%) showed signs of congenital toxoplasmosis in their first year of life; three (75%) had retinochoroidal scars, and one had cerebral calcifications. Two infants remained asymptomatic until 20 months of age. Conclusions The birth prevalence of congenital toxoplasmosis is high in the Brazilian state of Sergipe, with most of the infants showing ocular lesions. Preventive measures are strongly warranted.

Long-term impact of treated congenital toxoplasmosis on quality of life and visual performance

Background: Long-term evolution of congenital toxoplasmosis is not documented. We assessed the outcome of treated congenital toxoplasmosis in a cohort of adult individuals who had undergone ante- and postnatal treatment to provide information for pediatricians and parents on the evolution of the disease. Methods: We conducted a questionnaire study on 126 adults with congenital toxoplasmosis (mean age: 22.2 years; age range: 18–31 years) monitored regularly until the time of inclusion. The main outcome measures were quality of life (Psychological General Well-Being Index) and visual function (VF14 questionnaire), and the outcomes were correlated with disease-specific factors. Results: Of the 102 patients (80.9%) who were finally included in the study, 12 (11.8%) presented neurologic effects and 60 (58.8%) manifested ocular lesions; in the latter category, 13 individuals (12.7%) had reduced visual function. The overall global quality-of-life score (74.7 ± 14.2) was close to the expected normal range for the general population (73.7 ± 15.3). Overall, visual function was only slightly impaired (M = 97.3; 95% confidence interval, 95.8–98.8). Although disease-independent critical life circumstances were associated with a reduced Psychological General Well-Being Index, this index was not influenced by any of the clinical characteristics of congenital toxoplasmosis. Neurologic pathologies, reduced visual acuity, foveal location of the retinal lesion, and squinting contributed to decreased visual function at follow-up. Conclusions: Our data reveal that treated congenital toxoplasmosis has little effect on the quality of life and visual function of the affected individuals. These encouraging findings may help to alleviate the anxiety of affected individuals and their parents.

Prevalence of refractive errors and ocular disorders in preschool and school children of Ibiporã - PR, Brazil (1989 to 1996)

Purpose: To establish the prevalence of refractive errors and ocular disorders in preschool and schoolchildren of Ibiporã, Brazil. Methods: A survey of 6 to 12-year-old children from public and private elementary schools was carried out in Ibiporã between 1989 and 1996. Visual acuity measurements were performed by trained teachers using Snellen's chart. Children with visual acuity <0.7 in at least one eye were referred to a complete ophthalmologic examination. Results: 35,936 visual acuity measurements were performed in 13,471 children. 1.966 children (14.59%) were referred to an ophthalmologic examination. Amblyopia was diagnosed in 237 children (1.76%), whereas strabismus was observed in 114 cases (0.84%). Cataract (n=17) (0.12%), chorioretinitis (n=38) (0.28%) and eyelid ptosis (n=6) (0.04%) were also diagnosed. Among the 614 (4.55%) children who were found to have refractive errors, 284 (46.25%) had hyperopia (hyperopia or hyperopic astigmatism), 206 (33.55%) had myopia (myopia or myopic astigmatism) and 124 (20.19%) showed mixed astigmatism. Conclusions: The study determined the local prevalence of amblyopia, refractive errors and eye disorders among preschool and schoolchildren.

Influência da redução medicamentosa da pressão intra-ocular na medida da espessura da camada de fibras nervosas da retina de olhos hipertensos e glaucomatosos pela polarimetria de varredura a laser

PURPOSE: To evaluate changes in retinal nerve fiber layer thickness as measured by scanning laser polarimetry (SLP) after the use of medication to reduce intraocular pressure (IOP) in glaucomatous or ocular hypertensive patients. METHODS: The authors prospectively enrolled 37 eyes of 37 patients in whom IOP was reduced by more than 25% after the use of medication. The images were obtained before and 15 to 30 days after the introduction of medication. The SLP parameters measured before and after the use of medication were compared using paired Student's t Test. RESULTS: The mean IOP was significantly reduced from 26.57±4.23 mmHg to 16.54 ±2.92 mmHg after the use of medication (p<0.05). None of the 10 SLP analyzed parameters was significantly affected by the reduction of IOP with medication (p>0.05). CONCLUSION: The retinal nerve fiber layer thickness, as measured by SLP, is not affected by the reduction of IOP with medication in patients with glaucoma or ocular hypertension.

Ocular findings in Brazilian identical twins with Cohen syndrome: case report

A case of identical male twins with Cohen syndrome who present multiple ophthalmic findings is reported. The patients were identical 16 year-old twin boys who showed down slanting eyelids, mild ptosis, high-grade myopia, small cortical lens opacities, posterior subcapsular cataracts, myotic and corectopic pupils with poor dilation due to focal iris atrophy and retinochoroidal dystrophy. Ophthalmologists must be aware of the ocular and systemic findings of Cohen syndrome in the evaluation of young patients with mental retardation and visual impairment.

Ocular masquerade syndrome associated with extranodal nasal natural killer/T-cell lymphoma: case report

A 33-year-old woman complained of unilateral eyelid edema and blurred vision. Initial ophthalmic examination disclosed anterior chamber reaction with keratic precipitates on the cornea, without posterior abnormalities. Anterior uveitis was treated. Despite that, patient showed rapidly progressive unilateral vision loss with optic nerve swelling. Systemic workup was inconclusive, as well as cranial magnetic resonance imaging and cerebrospinal fluid examination. Based on the hypothesis of optic neuritis, intravenous methylprednisolone pulse was performed with no success. During the following days, the patient presented pericardial effusion and cardiac tamponade, progressing to death. Necropsy was performed and diagnosis of extranodal natural killers/T-cell lymphoma, nasal type with ocular involvement was confirmed by immunohistochemistry.

Assessment of ocular surface toxicity after topical instillation of nitric oxide donors

PURPOSE: To evaluate the ocular surface toxicity of two nitric oxide donors in ex vivo and in vivo animal models: S-nitrosoglutathione (GSNO) and S-nitroso-N-acetylcysteine (SNAC) in a hydroxypropyl methylcellulose (HPMC) matrix at final concentrations 1.0 and 10.0 mM. METHODS: Ex vivo GSNO and SNAC toxicities were clinically and histologically analyzed using freshly excised pig eyeballs. In vivo experiments were performed with 20 albino rabbits which were randomized into 4 groups (5 animals each): Groups 1 and 2 received instillations of 150 µL of aqueous HPMC solution containing GSNO 1.0 and 10.0 mM, respectively, in one of the eyes; Groups 3 and 4 received instillations of 150 µL of aqueous HPMC solution-containing SNAC 1.0 and 10.0 mM, respectively, in one of the eyes. The contralateral eyes in each group received aqueous HPMC as a control. All animals underwent clinical evaluation on a slit lamp and the eyes were scored according to a modified Draize eye test and were histologically analyzed. RESULTS: Pig eyeballs showed no signs of perforation, erosion, corneal opacity or other gross damage. These findings were confirmed by histological analysis. There was no difference between control and treated rabbit eyes according to the Draize eye test score in all groups (p>0.05). All formulations showed a mean score under 1 and were classified as non-irritating. There was no evidence of tissue toxicity in the histological analysis in all animals. CONCLUSION: Aqueous HPMC solutions containing GSNO and SNAC at concentrations up to 10.0 mM do not induce ocular irritation.

Evaluation of iris color stability in ocular prosthesis

Accurate iris reproduction in the fabrication of ocular prosthesis in order to match the remaining eye is a key factor to mask the loss and achieve an esthetic outcome for anophthalmic patients. This study evaluated the stability of acrylic paints used for replicating iris color in ocular prostheses by the analysis of two factors: the temperature of the acrylic resin polymerization cycle during prosthesis fabrication and the incidence of sun light, which is the main photodegrading agent undermining the longevity of ocular prostheses. An accelerated aging assay was used for both analyses. Specimens simulating the prosthetic iris in the colors blue, yellow, black, brown and green were fabricated, and were submitted to a colorimetric reading before and after undergoing the thermal conditions of acrylic resin polymerization. Next, the specimens were submitted to an artificial accelerated aging assay with ultraviolet radiation A and weekly colorimetric readings during a 3-week period. The color change (??*) values for the four specimens painted with the same color paint were averaged and the resulting values were considered for statistical analysis. Levine's test and Student's t-test were used to analyze the influence of the temperature of the polymerization cycle during prosthesis fabrication on the color stability of each acrylic resin paint. Friedman's test for three dependent samples was used for analysis of color photodegradation as function of time. Significance level was set at 0.05 for all analyses. It was observed that, after the action of the temperature of the polymerization cycle, alteration above clinically acceptable level of ??*> 3.3 was observed only for the yellow color. After the accelerated aging assay, there were statistically significant differences (p<0.05) as a function of time in the green, brown, black and blue colors. Changes were clinically acceptable for the brown and black colors; slightly above the clinically acceptable limit for the green color; and significantly high and impracticable from a clinical standpoint for the blue color. There was no statistically significant differences (p>0.05) for the yellow color, which presented color change only a little above the clinically acceptable limit. In conclusion: 1. Only the yellow color presented alterations above the clinically acceptable levels after the polymerization cycle; 2. After accelerated aging, there was no changes in the yellow color above the clinically acceptable levels; 3. For the green color, degradation was significant and slightly above the clinically acceptable levels; 4. The black, brown and blue colors presented significant alterations as function of time; the alterations of the brown and black colors were within acceptable clinical levels, while the blue color presented a more accentuated degradation over time.

A poloxamer/chitosan in situ forming gel with prolonged retention time for ocular delivery

The aim of the present work was to obtain an ophthalmic delivery system with improved mechanical and mucoadhesive properties that could provide prolonged retention time for the treatment of ocular diseases. For this, an in situ forming gel comprised of the combination of a thermosetting polymer, poly (ethylene oxide)-poly (propylene oxide)-poly (ethylene oxide) (PEO-PPO-PEO, poloxamer), with a mucoadhesive agent (chitosan) was developed. Different polymer ratios were evaluated by oscillatory rheology, texture and mucoadhesive profiles. Scintigraphy studies in humans were conduced to verify the retention time of the formulations developed. The results showed that chitosan improves the mechanical strength and texture properties of poloxamer formulations and also confers mucoadhesive properties in a concentration-dependent manner. After a 10-min instillation of the poloxamer/chitosan 16:1 formulation in human eyes, 50-60% of the gel was still in contact with the cornea surface, which represents a fourfold increased retention in comparison with a conventional solution. Therefore, the developed formulation presented adequate mechanical and sensorial properties and remained in contact with the eye surface for a prolonged time. In conclusion, the in situ forming gel comprised of poloxamer/chitosan is a promising tool for the topical treatment of ocular diseases. (C) 2010 Elsevier B.V. All rights reserved.

Excised Porcine Cornea Integrity Evaluation in an in vitro Model of Iontophoretic Ocular Research

Background/Aims: It is a challenge to adapt traditional in vitro diffusion experiments to ocular tissue. Thus, the aim of this work was to present experimental evidence on the integrity of the porcine cornea, barrier function and maintenance of electrical properties for 6 h of experiment when the tissue is mounted on an inexpensive and easy-to-use in vitro model for ocular iontophoresis. Methods: A modified Franz diffusion cell containing two ports for the insertion of the electrodes and a receiving compartment that does not need gassing with carbogen was used in the studies. Corneal electron transmission microscopy images were obtained, and diffusion experiments with fluorescent markers were performed to examine the integrity of the barrier function. The preservation of the negatively charged corneal epithelium was verified by the determination of the electro-osmotic flow of a hydrophilic and non-ionized molecule. Results: The diffusion cell was able to maintain the temperature, homogenization, porcine epithelial corneal structure integrity, barrier function and electrical characteristics throughout the 6 h of permeation experiment, without requiring CO(2) gassing when the receiving chamber was filled with 25 m M of HEPES buffer solution. Conclusion: The system described here is inexpensive, easy to handle and reliable as an in vitro model for iontophoretic ocular delivery studies. Copyright (C) 2010 S. Karger AG, Basel

Influence of insulin treatment on the lacrimal gland and ocular surface of diabetic rats

Previous studies have observed changes in the lacrimal gland and ocular surface related to diabetes mellitus and related it to insulin resistance or insufficiency and oxidative damage. The aim of this study was to evaluate whether insulin treatment inhibits those changes. Diabetes was induced in male Wistar rats with a single intravenous injection of streptozotocin and a subgroup was treated with insulin. After 5 and 10 weeks, the three groups (n = 5-10/group/experimental procedure) were compared for biochemical, functional, and histological parameters. After 5 weeks, changes in morphology and increased numbers of lipofucsin-like inclusions were observed in lacrimal glands of diabetic but not insulin-treated rats. After 5 weeks, malonaldehyde and total peroxidase activity were significantly higher in diabetic rats, but similar to control in insulin-treated diabetic rats (P = 0.03, P = 0.02, respectively). Our data indicate that diabetes induces histological alterations in lacrimal gland and suggests that hyperglycemia-related oxidative stress may participate in diabetic dry eye syndrome. Prevention by insulin replacement suggests direct hormone action and/or benefit by early sub optimal metabolic control.