Toxoplasmosis in the outer retina.

Objective: To present a case of ocular toxoplasmosis. Materials and methods: A sixteen-year-old female patient presented to our clinic with complaints regarding decreased vision in her right eye (BCVA 0.5), starting five days before the exam. Her anamnestic data revealed a previous history of ocular toxoplasmosis in her left eye. OCT scans of the inner retina identified a huge cystic space, located posterior to the inner line, off the outer plexiform layer, with a small amount of hyperreflective foci. Other features of OCT included membranous-like structures on inner borders and elongation and splitting of the inner segment/outer segment junction. In later stages, beginning signs of retinitis and scaring could be observed. Results: The patient was treated with sulfamethoxazole/trimethoprim and prednisolone. After two weeks, total regression occurred and visual acuity and OCT remained stable for 6 months (BCVA 1.0). Discussion: Ocular toxoplasmosis can cause significant vision loss due to retinitis and scarring. Following treatment with sulfamethoxazole/trimethoprim and prednisolone, the patient's condition improved significantly and her visual acuity remained stable. Conclusion: On clinical examination and using OCT, rare morphological cystoid spaces (CS) can be identified as huge outer retina cysts (HORC), which are pathognomonic for posterior uveitis. Abbreviations: HORC = huge outer retinal cyst, OCT = optical coherence tomography, BCVA = best corrected visual acuity, CS = cyst space, OPL = outer plexiform layer, HRF = hyper reflective foci, RPE = retinal pigment epithelium, IS = inner segment, OS = outer segment, ERM = epiretinal membrane, PORT = punctate outer retinal toxoplasmosis, ELM = external limiting membrane.

Ocular toxoplasmosis following anti-tumour necrosis factor-α therapy combined with oral methotrexate therapy: A case report and review of literature.

Purpose: To report a case of ocular toxoplasmosis following long-term treatment with adalimumab and review the literature on ocular toxoplasmosis following anti-Tumour necrosis factor-α therapy. Method: A retrospective chart review of A 21-year-old male who developed retinochoroiditis in his left eye following adalimumab therapy combined with oral methotrexate. Result: A known patient of juvenile idiopathic arthritis (JIA) on adalimumab and oral methotrexate for the last four years presented to us with a blurring of vision for the last 15 days. Fundus examination of the left eye revealed severe vitritis and two patches of retinochoroiditis in the inferior part of the fundus. Subsequent investigations confirmed it to be a case of toxoplasma retinochoroiditis, and he responded to anti-toxoplasma treatment. A review of literature on a similar topic revealed five such cases, and the index case was the first such report in patients with JIA. Conclusion: The index case highlights the importance of early recognition and management of opportunistic infections in patients receiving biologicals.

Risk factors for recurrences and visual impairment in patients with ocular toxoplasmosis: A systematic review and meta-analysis.

BACKGROUND: Ocular toxoplasmosis (OT) is caused by the parasite Toxoplasma gondii. OT is the leading cause of posterior uveitis globally; it is a recurrent disease that may result in visual impairment and blindness. This systematic review and meta-analysis aim to summarize and evaluate the risk factors for recurrences, visual impairment, and blindness described in the literature worldwide. METHODS AND FINDINGS: We performed a systematic literature search in PubMed, Embase, VHL, Cochrane Library, Scopus, and DANS EASY Archive. All studies reporting patients with clinically and serologically confirmed OT presenting any clinical or paraclinical factor influencing recurrences, visual impairment, and blindness were included. Studies presenting secondary data, case reports, and case series were excluded. An initial selection was made by title and abstract, and then the studies were reviewed by full text where the eligible studies were selected. Then, the risk of bias was assessed through validated tools. Data were extracted using a validated extraction format. Qualitative synthesis and quantitative analysis were done. This study was registered on PROSPERO (CRD42022327836). RESULTS: Seventy two studies met the inclusion criteria. Fifty-three were summarized in the qualitative synthesis in three sections: clinical and environmental factors, parasite and host factors, and treatment-related factors. Of the 72 articles, 39 were included in the meta-analysis, of which 14 were conducted in South America, 13 in Europe, four in Asia, three multinational, two in North America and Central America, respectively, and only one in Africa. A total of 4,200 patients with OT were analyzed, mean age ranged from 7.3 to 65.1 year of age, with similar distribution by sex. The frequency of recurrences in patients with OT was 49% (95% CI 40%-58%), being more frequent in the South American population than in Europeans. Additionally, visual impairment was presented in 35% (95% CI 25%-48%) and blindness in 20% (95% CI 13%-30%) of eyes, with a similar predominance in South Americans than in Europeans. On the other hand, having lesions near the macula or adjacent to the optic nerve had an OR of 4.83 (95% CI; 2.72-8.59) for blindness, similar to having more than one recurrence that had an OR of 3.18 (95% CI; 1.59-6.38). Finally, the prophylactic therapy with Trimethoprim/Sulfamethoxazole versus the placebo showed a protective factor of 83% during the first year and 87% in the second year after treatment. CONCLUSION: Our Systematic Review showed that clinical factors such as being older than 40 years, patients with de novo OT lesions or with less than one year after the first episode, macular area involvement, lesions greater than 1 disc diameter, congenital toxoplasmosis, and bilateral compromise had more risk of recurrences. Also, environmental and parasite factors such as precipitations, geographical region where the infection is acquired, and more virulent strains confer greater risk of recurrences. Therefore, patients with the above mentioned clinical, environmental, and parasite factors could benefit from using prophylactic therapy.

In vitro and in vivo anti-Toxoplasma activities of HDAC inhibitor Panobinostat on experimental acute ocular toxoplasmosis.

Ocular toxoplasmosis (OT) is retinochoroiditis caused by Toxoplasma gondii infection, which poses a huge threat to vision. However, most traditional oral drugs for this disease have multiple side effects and have difficulty crossing the blood-retinal barrier, so the new alternative strategy is required to be developed urgently. Histone deacetylases (HDAC) inhibitors, initially applied to cancer, have attracted considerable attention as potential anti-Toxoplasma gondii drugs. Here, the efficacy of a novel HDAC inhibitor, Panobinostat (LBH589), against T. gondii has been investigated. In vitro, LBH589 inhibited the proliferation and activity of T. gondii in a dose-dependent manner with low toxicity to retinal pigment epithelial (RPE) cells. In vivo, optical coherence tomography (OCT) examination and histopathological studies showed that the inflammatory cell infiltration and the damage to retinal architecture were drastically reduced in C57BL/6 mice upon treatment with intravitreal injection of LBH589. Furthermore, we have found the mRNA expression levels of inflammatory cytokines were significantly decreased in LBH589-treated group. Collectively, our study demonstrates that LBH589 holds great promise as a preclinical candidate for control and cure of ocular toxoplasmosis.

Ocular toxoplasmosis, an overview focusing on clinical aspects.

Toxoplasma gondii is a widespread protozoan parasite infecting approximately one third of the world population. After proliferation of tachyzoites during the acute stage, the parasite forms tissue cysts in various anatomical sites and establishes chronic infection. Nowadays the nature of the interplay between the protozoan and its human host remains elusive. This is clearly evident in ocular toxoplasmosis, in which the parasite establishes an ambivalent relationship with the eye, manipulating the immune response and inducing variable initial lesions and further relapses. This review will focus on epidemiology and environmental, parasite and host related risk factors, clinical manifestations and laboratory findings, treatment and prophylaxis approaches in ocular toxoplasmosis. An image collection of patients referred to the Unit of Ophthalmology of Pisa's Hospital will be presented, too.

Spiramyin-loaded PLGA implants for the treatment of ocular toxoplasmosis: development, characterization, biocompatibility, and anti-toxoplasma activity.

Ocular toxoplasmosis is the major cause of infectious posterior uveitis worldwide, inducing visual field defect and/or blindness. Despite the severity of this disease, an effective treatment is still lacking. In this study, spiramycin-loaded PLGA implants were developed aiming at the treatment of ocular toxoplasmosis. Implants were manufactured by a hot-molding technique, characterized by Fourier Transform Infrared Spectroscopy, X-Ray Diffraction, Differential Scanning Calorimetry, Scanning Electron Microscopy; evaluated in terms of ocular biocompatibility by immunofluorescence, flow cytometry, cell migration, Hen's egg test-chorioallantoic membrane (HET-CAM) irritation test; and investigated in terms of in vitro efficacy against Toxoplasma gondii . Characterization techniques indicated that spiramycin was dispersed into the polymeric chains and both substances preserved their physical structures in implants. The HET-CAM test indicated that implants did not induce hemorrhage or coagulation, being non-irritant to the CAM. ARPE-19 cells showed viability by MTT assay, and normality in cell cycle kinetics and morphology, without stimulating cell death by apoptosis. Finally, they were highly effective against intracellular parasites without inducing human retinal pigment epithelial cell death. In conclusion, spiramycin-loaded PLGA implants represent a promising therapeutic alternative for the local treatment of ocular toxoplasmosis.

Heerfordt-Waldenström Syndrome, A Rare Presentation of Sarcoidosis in a Patient with Old Ocular Toxoplasmosis.

BACKGROUND: There are similarities between the ophthalmic presentation of toxoplasmosis and sarcoidosis, and there are some concerns of immunosuppressive treatments for sarcoidosis, which may lead to T. gondii reactivation. We report a rare case with acute sarcoidosis (Heerfordt- Waldenström syndrome) with a history of ocular toxoplasmosis from the North of Iran. CASE PRESENTATION: The patient was a 36-year-old woman with left painful eye and swollen parotid, right facial paresis, maculopapular rash in left eyebrow and erythema nodosa on both legs. Anti-Toxoplasma IgG antibody was positive, and IgM was not detectable. Radiographic findings on the chest revealed bilateral hilar lymphadenopathy. The initial treatment was sulfamethoxazole- trimethoprim to prevent the recurrence of retinal toxoplasmosis and corticosteroid and mycophenolate mofetil for sarcoidosis. The patient showed clinical and vision improvement without recurrences during three months follow-up. DISCUSSION: Ophthalmological examinations and laboratory tests to rule out toxoplasmosis could be considered in known cases of sarcoidosis, particularly in ocular sarcoidosis status. To the best of our knowledge, this is the first report of comorbidity of ocular toxoplasmosis/sarcoidosis from Iran and possibly the world.

Toxoplasmose sistêmica associada à forma ocular bilateral atípica mimetizando necrose retiniana aguda / Systemic toxoplasmosis associated to the atypical bilateral ocular involvement mimicking acute retinal necrosis

RESUMO A toxoplasmose ocular pode se manifestar de forma atípica, rara, bilateral e associada à necrose retiniana aguda. É apresentada em pacientes imunossuprimidos, resultando em grave perda visual, se não for solucionada rapidamente. Relata-se um caso atípico de toxoplasmose ocular em paciente diabético, que, em sua internação prévia, já evidenciava aspecto sistêmico, o qual foi elucidado pelo exame clínico oftalmológico e pela anamnese. Além disso, a rotina do setor de uveítes, ao solicitar as sorologias de forma direcionada e criteriosa, foi imprescindível para o diagnóstico da toxoplasmose sistêmica associado à lesão ocular atípica bilateral, mimetizando necrose retiniana aguda com desfecho favorável.

Abstract Ocular toxoplasmosis can present with an atypical, rare, bilateral involvement, and associated with acute retinal necrosis. It occurs in immunosuppressed patients, resulting in severe visual loss, if not quickly solved. We report an atypical case of ocular toxoplasmosis in a diabetic patient, who already showed a systemic aspect in a previous hospitalization, which was elucidated by the ophthalmologic examination and history. In addition, the routine of the uveitis sector requesting serology in a directed and careful way was essential for the diagnosis of systemic toxoplasmosis associated with atypical bilateral ocular lesion, mimicking acute retinal necrosis with good outcome.

Adjunctive bradyzoite-directed therapy for reducing complications of congenital toxoplasmosis.

Congenital toxoplasmosis is caused by in utero infection of the fetus with the intracellular parasite Toxoplasma gondii. Upon infection, the parasite forms life-long cysts in fetal brain and eyes which are resistant to the currently accepted therapy of pyrimethamine and sulfadiazine. These cysts commonly reactivate later in life causing chorioretinitis and visual impairment, and rarely cause neurological complications. I hypothesize that adjunctive, bradyzoite-directed therapies have the potential to alleviate a significant burden of disease by reducing cyst burden in neonatal brain and eyes. Atovaquone is perhaps the most promising drug for further evaluation given its low side-effect profile, established safety, and efficacy in animal models reducing cyst burden. Very limited observational data in humans suggests atovaquone may prevent Toxoplasma-associated chorioretinitis recurrence. Clinical trials are needed to evaluate it and other potential drugs as adjunctive treatment in congenital toxoplasmosis.

Optic nerve involvement in ocular toxoplasmosis: 12 year data from a tertiary referral center in Turkey / Acometimento de nervo óptico na toxoplasmose ocular: um relato de 12 anos de um centro de referência terciário na Turquia

ABSTRACT Purpose: To evaluate the prevalence, clinical characteristics, and types of optic nerve involvement in patients with ocular toxoplasmosis. Methods: For this retrospective cross-sectional study, we examined all patients with active ocular toxoplasmosis referred to our Uveitis Section during the last 12 years, and we included patients with optic nerve involvement in the study. The primary outcome was the prevalence of optic nerve involvement, and secondary outcomes included the types of optic nerve involvement and the final best-corrected visual acuity after treatment. Results: The prevalence of optic nerve involvement was 14.4%, with the leading cause being the activation of a juxtapapillary lesion (70.5%). We found papillitis in two eyes and neuroretinitis in two eyes (11.7% for each). We only detected one optic nerve involvement secondary to a distant active lesion (5.8%). Sixteen patients (94.1%) had unilateral ocular toxoplasmosis. The overall final best-corrected visual acuity after treatment was 10/10 (LogMAR = 0.0) excluding the three patients with a juxtapapillary scar involving the macula. Conclusions: Optic nerve involvement was common in patients with ocular toxoplasmosis. The main type of optic nerve involvement was caused by activation of an old juxtapapillary lesion. Treatment was quickly effective, but the best-corrected visual acuity was dependent on the presence of a scar in the papillomacular bundle.

RESUMO Objetivos: Avaliar a prevalência, características clínicas e tipos de acometimento do nervo óptico em pacientes com toxoplasmose ocular. Métodos: Para este estudo retrospectivo transversal, examinamos todos os pacientes com toxoplasmose ocular ativa encaminhados ao nosso Setor de Uveíte nos últimos 12 anos, e incluímos pacientes com comprometimento do nervo óptico no estudo. O resultado primário foi a prevalência do envolvimento do nervo óptico, e os resultados secundários incluíram os tipos de envolvimento do nervo óptico e a acuidade visual final melhor corrigida após o tratamento. Resultados: A prevalência de acometimento do nervo óptico foi 14,4%, sendo a principal causa a ativação de uma lesão justapapilar (70,5%). Encontramos papilite em dois olhos e neuroretinite em dois olhos (11,7% para cada um). Apenas detectamos um comprometimento do nervo óptico secundário a uma lesão ativa distante (5,8%). Dezesseis pacientes (94,1%) apresentavam toxoplasmose ocular unilateral. A acuidade visual final com melhor correção após o tratamento foi 10/10 (LogMAR= 0,0) excluindo os três pacientes com uma cicatriz justapapilar envolvendo a mácula. Conclusões: O comprometimento do nervo óptico foi comum em pacientes com toxoplasmose ocular. O principal tipo de comprometimento do nervo óptico foi causado pela ativação de uma lesão justapapilar antiga. O tratamento foi rapidamente eficaz, mas a acuidade visual final com melhor correção foi dependente da presença de uma cicatriz no feixe papilomacular.

Immune Mediators against Toxoplasma Gondii during Reactivation of Toxoplasmic Retinochoroiditis.

Purpose: The purpose of this article is to analyze possible associations between systemic and ocular cytokine levels and specific clinical ophthalmologic signs from patients with a reactivation of toxoplasmic retinochoroiditis (RTR). Methods: A total of 18 patients with an active RTR episode, 8 patients with inactive scars, and 14 control patients were included in the study. Serum samples and aqueous humor (AH) samples were analyzed for IFN (interferon)-γ, interleukin (IL)-10, and IL-6 levels by ELISA. Inflammation grade, location, and size of the retinochoroidal active lesion, sampling time, and time to resolution were recorded. Results: A significantly negative correlation between AH and serum levels of IFN-γ was detected (p < 0.05). Patients with an AH IFN-γ/IL-10 ratio lower than 1 were associated with the longest time to resolution and/or severe complications. Conclusion: Serum IFN-γ levels may be used as a prognostic marker for both time to resolution and the development of possible severe complications during a given RTR episode.

Deciphering ophthalmic adaptive inhibitors targeting RON4 of Toxoplasma gondii: An integrative in silico approach.

AIMS: Toxoplasma gondii (T. gondii) is an intracellular Apicomplexan parasite and a causative agent of toxoplasmosis in human. Its parasitic invasion leads to encephalitis, uveitis, chorioretinitis and congenital infection. Host invasion by T. gondii is mediated by Moving junction (MJ) complex formed by secretory proteins such as micronemes and Rhoptry Neck proteins (RONs). Among these secretory proteins, RON4 shows major interactions with RON2 and RON5 of MJ complex and is also found to facilitate invasion by interacting with ß-tubulin of the host. Therefore, drug targeting of RON4 is considered to be an effective modality to inhibit host invasion. MAIN METHODS: Hence, in this study, we have implemented High throughput virtual screening (HTVS) against predicted novel druggable cavity on RON4, in order to prioritize potential inhibitors. This study also specifically focuses on identifying potential drugs that are ocular accommodative towards targeting ocular toxoplasmosis. Thus, the small molecules resulting from HTVS were subjected to stringent multi-level precision screening which involves PASS prediction, Density functional theory analysis, Binding Free Energy Calculations and stability of complex formation during molecular dynamics simulation to prioritize the potential hits. KEY FINDINGS: Among the compounds from NCI chemical library, five (338683, 333739, 686585, 159706, 405935) were found to surpass all the stringent filtration criteria. SIGNIFICANCE: Based on comparatively analysis, it was inferred that 333739 (benzyl 2-((2-(((benzyloxy) carbonyl) amino)-3-hydroxybutanoyl) amino) propanoate) to be highly potential in comparison to other compounds and shall prove to be an efficient inhibitor of RON4 in ocular toxoplasmosis.

False Negative Toxoplasma Serology in an Immunocompromised Patient with PCR Positive Ocular Toxoplasmosis.

PURPOSE: The authors report a case of a 60-year-old Caucasian male with a background of treated Chronic Lymphocytic Leukaemia (CLL) with secondary hypogammaglobulinaemia present with toxoplasma chorioretinitis and negative serum toxoplasma serology on presentation and on subsequent reactivation. METHODS: Retrospective case notes review with fundal photographs. RESULTS: In this case, on initial presentation and on recurrence, the patient's serum anti-Toxoplasma IgG remained negative. The diagnosis was made on quantitative PCR of vitreous initially and aqueous humor on reactivation. CONCLUSIONS: Despite negative serology, one must still consider ocular toxoplasmosis especially in CLL patients where the clinical picture could be compatible. Hypogammaglobulinaemia, the inability to produce IgG antibodies, is a well-recognized complication of CLL. Intraocular fluid sampling is essential in these cases where the sensitivity of PCR on either aqueous or vitreous humor has been shown to be higher in immunocompromised patients.

Current Practices in Ocular Toxoplasmosis: A Survey of Brazilian Uveitis Specialists.

PURPOSE: To describe treatment practices for ocular toxoplasmosis among members of the Brazilian Uveitis Society. METHODS: An online questionnaire sent to specialists, between October 2014 and March 2015. RESULTS: Most respondents (67.9%) treat all active cases. Most specialists consider visual acuity <20/200 (88.2%), severe vitreous inflammation (94.1%), and ocular disease during acquired infection (88.2%) as absolute indications for treatment. Systemic steroids are associated with anti-toxoplasmic therapy in most cases by 50.9% of the respondents. For immunocompetent individuals, 57.4% of the respondents chose trimethoprim/sulfamethoxazole. Classical therapy (sulfadiazine/pyrimethamine) is preferred most for patients with central lesions (70.4%), immunosuppression (68.4%), acquired infection (70.4%), and atypical forms (74.1%). For patients with frequent relapses, 84.9% of the respondents preferred antibiotic prophylaxis. CONCLUSIONS: Treatment patterns of ocular toxoplasmosis are not uniform among Brazilian specialists. Most specialists treat all cases of active retinochoroiditis. Typical cases are more frequently treated with trimethoprim/sulfamethoxazole. However, classical therapy is the regimen of choice when lesions are considered more severe.

Acometimento visceral e ocular simultâneo em infecção por toxocara canis acompanhado de farmacodermia / Concurrent visceral and ocular involvementin toxocara canis infection and pharmacodermia

A toxocaríase humana é uma infecção parasitária de distribuição mundial causada pelos nematelmintos das espécies Toxocara canis e Toxocara cati, presentes no intestino do cão e do gato, respectivamente. Clinicamente, na maioria das vezes, é assintomática, porém pode apresentar-se de duas formas: visceral ou ocular. Visceralmente, gera uma síndrome hipereosinofílica crônica, acompanhada por leucocitose e hepatomegalia, podendo ocorrer algum grau de infiltrado pulmonar e febre. Na toxocaríase ocular, ocorre uveite intermediária ou posterior, podendo haver formação de granuloma, geralmente unilateral. O acometimento misto é raro, o que motivou este relato. Trata-se de paciente de 19 anos, sexo masculino, que apresentou como sintoma inicial perda da acuidade visual em olho esquerdo. Recebeu tratamento, sem melhora, com sulfametoxazol + trimetoprima e corticoide, fazendo farmacodermia. Evoluiu com diarreia, febre, dor abdominal e hepatoesplenomegalia. Descartadas infecções agudas por toxoplasmose, sífilis, vírus da imunodeficiência humana (HIV), citomegalovirose e dengue; apresentou leucocitose com hipereosinofilia. Foi solicitada sorologia para toxocaríase, confirmando esta infecção. Após o tratamento, apresentou completa remissão dos sintomas. O objetivo aqui foi debater os fatores confundidores, diagnósticos diferenciais, necessidade de exames complementares específicos e conduta terapêutica, de acordo com o quadro clínico.(AU)

Human toxocariasis is a worldwide parasitic infection caused by ascarid nematodes species: Toxocara canis and Toxocara cati, that are present in the intestines of dogs and cats, respectively. Although clinically, most human infections are asymptomatic, two syndromes of human toxocariasis are recognized: visceral and ocular. The visceral form is a hypereosinophilic syndrome accompanied by leukocytosis, hepatomegaly, some degree of pulmonary infiltrate and fever. In ocular toxacariasis there is intermediate or posterior uveitis, and there may be granuloma formation, usually unilateral. The simultaneous involvement of the two forms is rare, which is what, motivated this report. It is a 19-year-old male patient who initially presented loss of visual acuity in the left eye. He received treatment, without improvement, with sulfamethoxazole-trimethoprim and corticoid, causing a pharmacodermia. He developed diarrhea, fever, abdominal pain and hepatosplenomegaly. It was discarded acute infections by toxoplasmosis, syphilis, human immunodeficiency virus (HIV), cytomegalovirus and dengue. The patient also manifested leukocytosis with hypereosinophilia. Serological testing for toxacariasis was requested, diagnosing the infection. After treatment, he progressed with full symptoms remission. The aim of this study was to discuss confounding factors, differential diagnoses, the need for specific complementary exams and therapeutic management, according to the clinical aspects.(AU)

DRESS syndrome in ophthalmic patients.

Drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome is a rare and potentially fatal adverse drug reaction associated with skin rash, fever, eosinophilia, and multiple organ injury. A number of pharmacological agents are known to cause DRESS syndrome such as allopurinol, anticonvulsants, vancomycin, trimethoprime-sulfamethoxazole, and pyrimethamine-sulfadiazine. Here, we describe two patients who developed DRESS syndrome during ocular treatment. The first case was being treated for late postoperative endophthalmitis with topical antibiotics, intravenous cephalothin, meropenem, and intravitreal injection of vancomycin and ceftazidime before symptoms developed. We were unable to identify the causal drug owing to the large number of medications concurrently administered. The second case presented with DRESS syndrome symptoms during ocular toxoplasmosis treatment. In this case, a clearer association with pyrimethamine-sulfadiazine was observed. As a result of the regular prescription of pharmacological agents associated with DRESS syndrome, ophthalmologists should be aware of the potentially serious complications of DRESS syndrome.

DRESS syndrome in ophthalmic patients / Síndrome DRESS em pacientes oftalmológicos

ABSTRACT Drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome is a rare and potentially fatal adverse drug reaction associated with skin rash, fever, eosinophilia, and multiple organ injury. A number of pharmacological agents are known to cause DRESS syndrome such as allopurinol, anticonvulsants, vancomycin, trimethoprime-sulfamethoxazole, and pyrimethamine-sulfadiazine. Here, we describe two patients who developed DRESS syndrome during ocular treatment. The first case was being treated for late postoperative endophthalmitis with topical antibiotics, intravenous cephalothin, meropenem, and intravitreal injection of vancomycin and ceftazidime before symptoms developed. We were unable to identify the causal drug owing to the large number of medications concurrently administered. The second case presented with DRESS syndrome symptoms during ocular toxoplasmosis treatment. In this case, a clearer association with pyrimethamine-sulfadiazine was observed. As a result of the regular prescription of pharmacological agents associated with DRESS syndrome, ophthalmologists should be aware of the potentially serious complications of DRESS syndrome.

RESUMO Síndrome DRESS (drug reaction with eosinophilia and systemic symptoms) é uma reação adversa a medicamentos rara e potencialmente fatal, associada à rash cutâneo, febre, eosinofilia e lesão de múltiplos órgãos. Algumas drogas podem desencadeá-la, como: alopurinol, anticonvulsivantes, vancomicina, sulfametoxazol-trimetoprim, sulfadiazina-pirimetamina, entre outras. Descrevemos dois casos que desenvolverem DRESS síndrome durante tratamento ocular. O primeiro caso apresentou os sintomas durante tratamento para endoftalmite pós-operatória tardia com antibióticos tópicos, cefalotina e meropenem intravenosos e injeção intravítrea de vancomicina e ceftazidima; não podemos identificar a droga causadora, pois múltiplas medicações foram utilizadas. O segundo caso desenvolveu os sintomas durante tratamento clássico para toxoplasmose ocular, então a associação com sulfadiazina-pirimetamina foi mais clara. Como muitos oftalmologistas prescrevem regularmente drogas que podem desencadear a síndrome DRESS, esse diagnóstico deve ser lembrado já que pode levar a sérias complicações.

Real-time PCR using the 529†bp repeat element for the diagnosis of atypical ocular toxoplasmosis.

BACKGROUND: Ocular toxoplasmosis may present in atypical fashion, particularly in immunosuppressed patients, and PCR is an important diagnostic tool especially when differentiating from other infectious causes. METHODS: A descriptive case-series demonstrating the use of a novel real-time PCR protocol targeting 529 bp repeat element, a multicopy and highly conserved fragment, in Toxoplasma gondii genome. This was designed and established by our microbiology service following independent, external validation. RESULTS: Three immunosuppressed patients presenting to a tertiary uveitis referral centre with unilateral, severe, sight-threatening uveitis are described. One patient presented with a large focus of sight-threatening retinitis and occlusive vasculitis while on systemic immunosuppression with azathioprine and adalimumab for Crohn's disease. One patient with chronic lymphocytic leukaemia presented with severe posterior uveitis and total retinal detachment. Finally, the third patient presented with severe retinitis adjacent to the optic nerve and vitritis causing acute vision loss. HIV infection was subsequently identified. In all three cases, the cause of inflammation was not clear from clinical examination alone and prompt treatment was required to prevent permanent vision loss. Intraocular sampling and PCR testing was performed including testing for toxoplasmosis, herpesviruses and syphilis. CONCLUSIONS: The novel real-time PCR assay described is more sensitive than those targeting the Toxoplasma B1 gene owing to the higher number of repeats and highly conserved sequence level. This technique can be applied in clinical practice and provides a valuable tool for the rapid diagnosis of ocular toxoplasmosis.