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1.
Arq. bras. oftalmol ; 84(5): 474-480, Sept.-Oct. 2021. tab
Article in English | LILACS-Express | LILACS | ID: biblio-1339208

ABSTRACT

ABSTRACT Purpose: The aim of this study was to analyze patient data and the laboratory results of corneal samples collected from patients followed at the Ophthalmology Department, Hospital São Paulo, Brazil over a 30-year period, and correlate the analize with contact lens wearing. Methods: Corneal samples from patients diagnosed clinically with microbial keratitis between January 1987 and December 2016 were included in this study. Cultures that were positive for bacteria, fungi, and Acanthamoeba spp. were analyzed retrospectively. To ascertain if the number of patients with contact-lens-associated microbial keratitis (as a risk factor for microbial infection) changed over time, the analysis was divided into three decades: 1987-1996, 1997-2006, and 2007-2016. Information pertaining to patient gender and age, as well as type of organism isolated, were compared among these periods. Results: The corneal samples of 10.562 patients with a clinical diagnosis of microbial keratitis were included in the study, among which 1.848 cases were related to the use of contact lenses. The results revealed that the frequency of contact-lens-associated microbial keratitis increased over the last two decades. Overall, females had contact-lens-associated microbial keratitis more frequently (59.5%). Patients aged 19-40 years also had contact-lens-associated microbial keratitis more frequently in all study periods. Staphylococcus spp. and Pseudomonas spp. were the most frequent Gram-positive and Gram-negative bacteria, respectively, in the microbial keratitis groups. Among the fungal cases of microbial keratitis, filamentous fungi were the most frequent fungi over the entire study period, with Fusarium spp. being the most frequent fungi in the group with microbial keratitis not associated with contact lens wearing (p<0.001). Samples positive for Acanthamoeba spp. and Pseudomonas spp. were significantly correlated with contact-lens-associated microbial keratitis (p<0.001). Conclusions: Females and young adults aged 19-40 years exhibited the highest frequency of contact-lens-associated microbial keratitis in our study. Staphylococcus spp. and Fusarium spp. were the predominant bacteria and fungi, respectively, isolated from corneal samples. Pseudomonas spp. and Acanthamoeba spp. were significantly correlated with contact-lens-associated microbial keratitis in this study.


RESUMO Objetivo: O objetivo deste estudo foi analisar da dos epidemiológicos de pacientes e resultados laboratoriais para todas as amostras de córnea coletadas de pacientes atendidos no Departamento de Oftalmologia do Hospital São Paulo, Brasil, durante um período de 30 anos e correlacionar com o uso de lentes de contato. Métodos: Amostras de córnea de pacientes com diagnóstico clínico de ceratite microbiana (de janeiro de 1987 a dezembro de 2016) foram incluídas neste estudo. Resultados laboratoriais para culturas positivas para bactérias, fungos e Acanthamoeba spp. foram analisados retrospectivamente. Para verificar se o número de pacientes com ceratite microbiana associada à lente de contato, fator de risco para infecção microbiana, mudou ao longo do tempo, a análise foi dividida em três décadas: 1987-1996, 1997-2006 e 2007-2016. As informações incluindo o sexo do paciente, idade e tipo de organismo isolado foram comparadas entre os períodos. A análise estatística foi realizada no software SAS/STAT 9.3 e SPSS (v20.0). Resultados: Amostras de córnea de 10.562 pacientes com ceratite microbiana foram incluídas no estudo, das quais 1.848 foram relacionadas ao uso de lentes de contato. Os resultados revelaram que a frequência de ceratite microbiana associada à lente de contato aumentou nas últimas duas décadas analisadas. No geral, os homens compreendiam uma proporção maior do grupo ceratite microbiana não associada à lente de contato (CMNLC) (60,3%) e as mulheres eram mais frequentes no grupo ceratite microbiana associada à lente de contato (59,5%). Pacientes com idade entre 19 e 40 anos foram mais frequentemente observados no grupo ceratite microbiana associada à lente de contato em todos os períodos. Staphylococcus spp. foi a bactéria Gram-positiva mais frequentes, enquanto Pseudomonas spp. foi a bactéria Gram-negativa nos grupos ceratite microbiana. Entre os fungos ceratite microbiana, os fungos filamentosos foram os fungos mais frequentes durante todo o período do estudo, com Fusarium spp. sendo o mais frequente no grupo ceratite microbiana não associada à lente de contato. Acanthamoeba spp. e Pseudomonas spp. amostras positivas foram significativamente correlacionadas com ceratite microbiana associada à lente de contato. Conclusões: A maior prevalência de ceratite microbiana associada à lente de contato no nosso estudo foi observada em mulheres e adultos jovens com idade entre 19 e 40 anos. Staphylococcus spp. e Fusarium spp. foram as bactérias e fungos predominantes isolados nas amostras da córnea. Pseudomonas spp. e Acanthamoeba spp. foram significativamente correlacionados a ceratite microbiana associada à lente de contato neste estudo.

2.
Article in Chinese | WPRIM | ID: wpr-908561

ABSTRACT

Objective:To investigate the risk factors and treatment outcome of recurrent Acanthamoeba keratitis (AK) after corneal transplantation. Methods:A serial case-observational study was carried out.Twenty-eight eyes of 28 patients with AK who underwent corneal transplantation in Shandong Eye Hospital from January 2012 to January 2019 were enrolled.All the eyes received corneal transplantation from failing to respond to topical and systemic anti- Acanthamoeba medical therapy, including 13 eyes that received penetrating keratoplasty (PKP) and 15 eyes that received lamellar keratoplasty (LKP). The corneal lesion was removed by a trephine with a diameter of 0.5 mm over infiltration area during PKP or LKP.The clinical features of recurrent AK were summarized, including recurrence time, site and signs, and the risk factors of AK recurrence were analyzed.Local and systemic anti- Acanthamoeba medical therapy was performed in all relapsed eyes, and secondary surgery was performed for the eyes with poor response to medication.The therapeutic outcome of recurrent AK was evaluated.The study adhered to the Declaration of Helsinki.This study protocol was approved by an Ethics Committee of Shandong Eye Hospital (No.201112). Results:In the 28 eyes, 7 eyes (25%) appeared recurrent AK after keratoplasty, including 2 eyes after PKP and 5 eyes after LKP.There was no significant difference in the recurrence rate between the two methods ( P=0.396). The recurrence rate of eyes that had used glucocorticoids drugs before operation was 57.14% (4/7), which was significantly higher in comparison with 14.29% (3/21) of eyes without glucocorticoids before surgery ( P=0.043). The recurrence rate of eyes with ulcer diameter ≥8.2 mm was 50.00% (5/10), which was significantly higher than 11.11% (2/18) of eyes with ulcer <8.2 mm ( P=0.036). The recurrent lesions began at the edge of implant bed accounted for 85.71% (6/7), and the recurrent lesions located below graft accounted for 14.29% (1/7). In 7 eyes with recurrent AK, 6 eyes were completely cured.Among recurrent AK eyes after LKP, 2 eyes were cured by long-term medical therapy, and 2 eyes were cured by extended-diameter LKP, and another 1 eye was cured by conjunctival flap covering surgery.One eye with recurrent AK after PKP was cured by extended-diameter PKP. Conclusions:The risk factors of recurrent AK after surgery are application of glucocorticoids before surgery and big lesions.Recurrent AK after surgery is curable by individualized therapy targeting to different clinical characteristics.

3.
International Eye Science ; (12): 1922-1926, 2021.
Article in Chinese | WPRIM | ID: wpr-887385

ABSTRACT

@#AIM:To investigate the application value of fluorescent staining technique in the detection of amoebic pathogens in corneal tissue biopsy, and to apply fluorescent staining technique in the histopathological diagnosis of Acanthamoeba keratitis(AK), comparing the results with those of hemotoxyiln-eosin staining(HE staining)and periodic acid-schiff staining(PAS staining), and analyzing the sensitivity and specificity of these three staining methods.<p>METHODS:Specimens of infected corneal tissue were collected from 74 cases(75 eyes), and then they were divided into an AK group and a non-Acanthamoeba keratitis(NAK)group based on the results of corneal scraping, culture and histopathological diagnosis. The tissues of consecutive sections were stained with HE staining, PAS staining and fluorescence respectively, and the sensitivity and specificity of the three staining methods for the diagnosis of AK were analyzed. Area under the curve(AUC)was calculated using the receiver operating characteristic(ROC)curve. Further analysis was performed to count the number of Acanthamoeba pathogens found by the three staining methods under the same magnification field of view at the same site, and to clarify the diagnostic value of fluorescent staining technique for AK.<p>RESULTS: The sensitivity of HE staining was 69%(27/39)with a specificity of 92%; the sensitivity of PAS staining was 62%(24/39)with a specificity of 97%, and the sensitivity of fluorescent staining was 95%(37/39)with a specificity of 97%. There were differences in the sensitivity of the three staining methods for the diagnosis of AK(χ2=19.857, <i>P</i><0.001), and pairwise comparison revealed that the differences between HE staining and fluorescent staining, PAS staining and fluorescent staining for the diagnosis of AK were statistically significant(<i>P</i>=0.003,<0.001), while the difference in sensitivity between HE staining and PAS staining for the diagnosis of AK was not statistically significant(<i>P</i>=0.978). The maximum AUC was 0.960 for fluorescence staining, followed by 0.804 for HE staining and 0.794 for PAS staining, respectively. The median number of amoeba cysts detected by HE staining, PAS staining and fluorescent staining at the same site under the same magnification field of view was 4(0, 11), 2(0, 9)and 12(3, 33), respectively(χ2=56.561, <i>P</i><0.001). Pairwise comparison revealed that the differences in the number of amoeba cysts found by HE staining and fluorescence staining, PAS staining and fluorescence staining were statistically significant(<i>P</i><0.001), while the difference in the number of amoeba cysts found by HE staining and PAS staining was not statistically significant(<i>P</i>=0.210). Fluorescently stained histopathological sections make it easier to identify amoebic pathogens.<p>CONCLUSION:Fluorescent staining technique is more sensitive to histopathological diagnosis of AK than HE staining and PAS staining, which can significantly improve the positive rate of detection of amoebic pathogens.

4.
Rev. cuba. oftalmol ; 33(1): e775, ene.-mar. 2020. graf
Article in Spanish | LILACS, CUMED | ID: biblio-1126722

ABSTRACT

RESUMEN Objetivo: Estandarizar una técnica de reacción en cadena de la polimerasa en tiempo real para la detección del parásito e identificar Acanthamoeba en líquidos conservantes de lentes de contacto. Métodos: Se realizó un estudio descriptivo observacional de corte transversal sobre la técnica de reacción en cadena de la polimerasa en tiempo real para la detección de Acanthamoeba, en el Instituto de Investigaciones en Ciencias de la Salud de la ciudad de Asunción, en Paraguay. Se analizaron 110 líquidos conservantes aportados por usuarios sanos de lentes de contacto, mediante reacción en cadena de la polimerasa en tiempo real y cultivo en medio PAGE - SDS. Resultados: Se estandarizó con éxito la técnica de reacción en cadena de la polimerasa en tiempo real con límite de sensibilidad de 1 pg/µL. Se aisló Acanthamoeba a partir de una muestra (1 por ciento) por método de cultivo, mientras que la carga parasitaria en el líquido conservante fue inferior al límite de detección de la reacción en cadena de la polimerasa en tiempo real. El ADN obtenido del cultivo de dicha muestra fue positivo para Acanthamoeba por este método. Conclusión: El sistema estandarizado presenta buena sensibilidad y podrá ser incorporado en los laboratorios que cuentan con acceso a equipos de reacción en cadena de la polimerasa en tiempo real para un diagnóstico rápido y más eficiente en casos de sospechas de queratitis amebiana. Recomendamos el uso combinado de métodos moleculares y cultivo para aumentar la potencia del diagnóstico, sobre todo en muestras donde la carga parasitaria es muy baja(AU)


ABSTRACT Objective: Standardize a real-time polymerase chain reaction technique for detection of the parasite and identify Acanthamoeba in contact lens solutions. Methods: A cross-sectional observational descriptive study was conducted about a real-time polymerase chain reaction technique for detection of Acanthamoeba at the Institute of Health Sciences Research in the city of Asunción, Paraguay. A total 110 solutions were analyzed, which were provided by healthy contact lens users, by real-time polymerase chain reaction and culture in SDS-PAGE medium. Results: Successful standardization was achieved of the real-time polymerase chain reaction technique with a sensitivity limit of 1 pg/µl. Acanthamoeba was isolated from one sample (1 percent) by culture, whereas the parasite load in the contact lens solution was below the detection limit of the real-time polymerase chain reaction technique. The DNA obtained from the culture of that sample was positive for Acanthamoeba by the real-time polymerase chain reaction technique method. Conclusion: The system standardized exhibits good sensitivity and may be incorporated into laboratories with real-time polymerase chain reaction technique equipment for a rapid and more efficient diagnosis of suspected amoebic keratitis. We recommend the combined use of molecular methods and culture to enhance diagnostic power, mainly in samples where the parasite load is very low(AU)


Subject(s)
Humans , Acanthamoeba/microbiology , Acanthamoeba Keratitis/etiology , Contact Lenses/adverse effects , Real-Time Polymerase Chain Reaction/methods , Epidemiology, Descriptive , Cross-Sectional Studies , Contact Lens Solutions/therapeutic use , Observational Studies as Topic
5.
Indian J Ophthalmol ; 2020 Mar; 68(3): 442-446
Article | IMSEAR | ID: sea-197861

ABSTRACT

Purpose: To report and analyze the outcomes of therapeutic deep anterior lamellar keratoplasty (DALK) in patients with advanced Acanthamoeba keratitis (AK). Methods: Medical records of microbiologically confirmed AK, underwent DALK from 2004 to 2017, were reviewed and the data related to early and late outcome including complications were retrieved. Outcome of cases with largest diameter of infiltrate ?8 mm at the time of surgery (advanced keratitis) were analyzed and compared with those with less severe keratitis (infiltrate size less than 8 mm). Results: Out of 23 patients of AK in whom DALK was performed, ten (43.4%) patients had advanced keratitis. Mean age of these patients was 38.7 ± 8.6 years (range, 25 to 56). Median visual acuity at presentation was 2.78 (IQR, 1.79–3.0) that improved to 1.79 (IQR, 0.70–2.78) postoperatively. Early complications included recurrence of AK in 2 (20%), Descemet's membrane detachment in 5 (50%), and persistent epithelial defect in 3 (30%) cases. Overall, 6 (60%) grafts failed, whereas 4 (40%) patients had clear graft at their last follow-up. Median follow-up of these cases was 5 months (IQR, 1.4–11.4). One graft developed stromal rejection, which resolved with increased dose of corticosteroids. In comparison, DALK performed for less severe keratitis (N = 13) had 1 (7.6%) recurrence and 2 (15.8%) grafts failure (OR, 8.25). The probability of one-year graft survival and eradication of infection was 32% and 74.1%, respectively, in advanced cases compared to 91.6% and 83.9% in less severe cases. Conclusion: Outcome of DALK in advanced Acanthamoeba keratitis is less favorable compared to those carried out for less severe keratitis cases.

7.
Arq. bras. oftalmol ; 82(2): 103-106, Mar.-Apr. 2019. tab
Article in English | LILACS | ID: biblio-989399

ABSTRACT

ABSTRACT Purpose: To report our initial experience in the treatment of Acanthamoeba keratitis with accelerated corneal collagen cross-linking. Methods: Retrospective chart review of patients diagnosed with Acanthamoeba keratitis with progressive corneal melting who were treated with accelerated collagen cross-linking. Results: A total of 6 eyes (5 patients) were reviewed. All the patients received adjuvant therapy with moxifloxacin and chlorhexidine. In 4 cases, the ulcer healed with a mean interval to epithelialization of 108.8 days (range 59-217). In 2 eyes, there was a persistent neurotrophic ulcer. The melting was not progressive in any case, nor did any eye required emergency penetrating keratoplasy. Conclusion: This study suggests a beneficial effect of accelerated collagen cross-linking in cases of Acanthamoeba keratitis with corneal melting. Thus, collagen cross-linking may be considered as adjuvant treatment for Acanthamoeba keratitis.


RESUMO Objetivo: Relatar nossa experiência inicial no tra tamento da ceratite por Acanthamoeba com reticulação acelerada de colágeno corneano. Métodos: Revisão retrospectiva de prontuários de pacientes diagnosticados com ceratite por Acanthamoeba, com deformação progressiva da córnea, tratados com reticulação acelerada de colágeno. Resultados: Seis olhos (5 pacientes) foram incluídos. Todos os pacientes receberam terapia adjuvante com moxifloxacina e clorexidina. Em 4 casos, a úlcera cicatrizou com uma média de epitelização de 108,8 dias (amplitude de 59-217 dias). Em dois pacientes, a úlcera apresentou um comportamento neurotrófico. A deformação não foi progressiva em nenhum dos pacientes e nenhum dos olhos exigiu ceratoplastia penetrante de emergência. Conclusão: Este estudo sugeriu um efeito benéfico da reticulação acelerada de colágeno em casos de ceratite por Acanthamoeba infecciosa com deformação corneal. A reticulação de colágeno parece ser uma alternativa coadjuvante possível para casos de ceratite por Acanthamoeba.


Subject(s)
Humans , Female , Middle Aged , Aged , Aged, 80 and over , Riboflavin/therapeutic use , Ultraviolet Therapy/methods , Acanthamoeba Keratitis/therapy , Collagen/metabolism , Photosensitizing Agents/therapeutic use , Cross-Linking Reagents/therapeutic use , Acanthamoeba Keratitis/metabolism , Corneal Ulcer/metabolism , Corneal Ulcer/therapy , Follow-Up Studies , Collagen/drug effects , Collagen/radiation effects , Cornea/drug effects , Cornea/radiation effects , Cornea/metabolism
8.
Article in English | WPRIM | ID: wpr-761775

ABSTRACT

Acanthamoeba keratitis (AK) is a rare sight-threatening corneal infection, often reporting from contact lens wearers. An asymptomatic human immunodeficiency virus (HIV)-infected Thai male without history of contact lens use complained foreign body sensation at his left eye during motorbike riding. He had neither specific keratitis symptoms nor common drugs responding, which contributed to delayed diagnosis. By corneal re-scraping, Acanthamoeba-like cysts were detected by calcofluor white staining and agar culture. The etiological agent obtained from the culture was molecularly confirmed by Acanthamoeba spp.-specific PCR, followed by DNA sequencing. The results from BLAST and phylogenetic analysis based on the DNA sequences, revealed that the pathogen was Acanthamoeba T4, the major genotype most frequently reported from clinical isolates. The infection was successfully treated with polyhexamethylene biguanide resulting in corneal scar. This appears the first reported AK case from a non-contact lens wearer with HIV infection in Thailand. Although AK is sporadic in developing countries, a role of free-living Acanthamoeba as an opportunistic pathogen should not be neglected. The report would increase awareness of AK, especially in the case presenting unspecific keratitis symptoms without clinical response to empirical antimicrobial therapy.


Subject(s)
Acanthamoeba Keratitis , Acanthamoeba , Agar , Asian Continental Ancestry Group , Base Sequence , Corneal Injuries , Delayed Diagnosis , Developing Countries , Foreign Bodies , Genotype , HIV Infections , HIV , Humans , Keratitis , Male , Off-Road Motor Vehicles , Polymerase Chain Reaction , Sensation , Sequence Analysis, DNA , Thailand
9.
Rev. Soc. Bras. Med. Trop ; 51(5): 716-719, Sept.-Oct. 2018. graf
Article in English | LILACS | ID: biblio-957453

ABSTRACT

Abstract We report an Acanthamoeba keratitis case associated with the use of contact lens in a 28-year-old female from Brasília, Brazil. Samples from corneal scraping and contact lens case were used for culture establishment, PCR amplification, and partial sequencing (fragments of ~400kb) of small subunit rDNA; both culture and PCR were positive. The sequence analyses of the cornea and of isolates from the contact lens case showed similarity with the T4 genotype. To the best of our knowledge, this is the first report of T4 Acanthamoeba keratitis case from the Midwest region of Brazil.


Subject(s)
Humans , Male , Adult , Acanthamoeba/genetics , Acanthamoeba Keratitis/diagnosis , Contact Lenses/parasitology , Acanthamoeba/isolation & purification , Acanthamoeba Keratitis/surgery , Acanthamoeba Keratitis/etiology , Genotype
10.
Braz. j. microbiol ; 49(supl.1): 205-212, 2018. tab, graf
Article in English | LILACS | ID: biblio-974346

ABSTRACT

Abstract This study compares patients with and without non-viral microbial keratitis in relation to sociodemographic variables, clinical aspects, and involved causative agent. Clinical aspects, etiology and therapeutic procedures were assessed in patients with and without keratitis that were diagnosed in an Eye Care Center in Campo Grande, MS, Brazil. Patients were divided into two groups: (a) cases: 64 patients with non-viral microbial keratitis diagnosed at biomicroscopy; and (b) controls: 47 patients with other eye disorders that were not keratitis. Labor activity related to agriculture, cattle raising, and contact lens use were all linked to keratitis occurrence (p < 0.005). In patients with keratitis, the most common symptoms were pain and photophobia, and the most frequently used medicines were fourth-generation fluoroquinolones (34.4%), amphotericin B (31.3%), and natamycin (28.1%). Microbial keratitis evolved to corneal perforation in 15.6% of cases; transplant was indicated in 10.9% of cases. Regarding the etiology of this condition, 23 (42.2%) keratitis cases were caused by bacteria (Pseudomonas aeruginosa, 12.5%), 17 (39.1%) by fungi (Fusarium spp., 14.1% and Aspergillus spp., 4.7%), and 4 (6.3%) by Acanthamoeba. Patients with keratitis present with a poorer prognosis. Rapid identification of the etiologic agent is indispensable and depends on appropriate ophthalmological collection and microbiological techniques.


Subject(s)
Humans , Male , Female , Adolescent , Adult , Aged , Aged, 80 and over , Young Adult , Bacteria/isolation & purification , Bacterial Infections/microbiology , Fungi/isolation & purification , Keratitis/microbiology , Mycoses/microbiology , Bacteria/classification , Bacteria/drug effects , Bacteria/genetics , Bacterial Infections/drug therapy , Brazil , Fungi/classification , Fungi/drug effects , Fungi/genetics , Keratitis/drug therapy , Middle Aged , Anti-Bacterial Agents/pharmacology , Mycoses/drug therapy , Antifungal Agents/pharmacology
11.
Article in English | IMSEAR | ID: sea-135354

ABSTRACT

Background & objectives: Acanthamoeba keratitis (AK) is a painful and vision-threatening ocular infection. The differentiation of Acanthamoeba at the species and subspecies level is complicated. Nearly all the AK isolates have been shown to belong to T4 genotype when analysed by ribosomal RNA gene sequences and there is no universally acceptable method for differentiation of different subtypes of T4. The purpose of this study was to attempt further discrimination of T4 genotypes. Methods: In the present investigation, 15 Acanthamoeba isolates obtained from cornea of keratitis patients were subjected to fluorescence amplified fragment length polymorphism (FAFLP) genotyping to differentiate T4 subtypes. Results: FAFLP profiles showed five distinct clusters (I to V) within T4 clonal complex which clearly depicted genetic differences among the isolates of T4 sequence type of Acanthamoeba. Interpretation & conclusions: Our study demonstrated the usefulness of FAFLP for reliable differentiation of T4 clonal complex of Acanthamoeba.

12.
Article in English | IMSEAR | ID: sea-127137

ABSTRACT

Acanthamoeba Keratitis (AK) is a serious sight threatening infection of the cornea. We report here a case of Acanthamoeba keratitis in a young healthy male. He presented to us with a history of minor trauma in his left eye & immediately he washed his eye with stagnant dirty water. Diagnosis was based on observation of actively motile trophozoites and cyst in normal saline wet mount preparation of the corneal ulcer scraping. Patient was treated with available antiamoebic drugs (Topical Neosporin, Clotrimazol, Tab. Ketaconazal, Polymixin-B). Patient responded extremely well to medical line of treatment.


Subject(s)
Acanthamoeba Keratitis
13.
Article in English | WPRIM | ID: wpr-626504

ABSTRACT

if not treated. This study was therefore performed to evaluate the effectiveness of eyedrop antibiotics on eight Acanthamoeba spp. isolates, of which four were clinical isolates and the remaining four from the environment. Three different eyedrop antibiotics (neomycin, ciprofloxacin and gentamicin) currently available in the market and ready for use were tested. Cyst suspension from all strains were tested against eyedrop antibiotics, respectively. After 48 hours of incubation period, the solutions were filtered and the filtered membranes were put onto non-nutrient agar lawn with E. coli. Bab 3 The plates were examined daily for Acanthamoeba trophozoites under inverted microscope until day 14. Neomycin, ciprofloxacin and gentamicin were found to be effective against Acanthamoeba spp. cysts for all test strains.

14.
Arq. bras. oftalmol ; 71(3): 430-433, maio-jun. 2008. ilus, tab
Article in English | LILACS | ID: lil-486126

ABSTRACT

This is the report of a case of bilateral Acanthamoeba keratitis in a 19-year-old woman who bought a pair of disposable soft contact lenses in a boutique. She wore this same pair of lenses for 3 months daily without the appropriate care. This led to bilateral corneal transplantation with cataract extraction and also trabeculectomy in the right eye. When last seen, both grafts were crystal clear but the visual acuities were far from satisfactory. She also had bilateral secondary glaucoma, barely controlled by topical medication. Actually, the physical features and the wearing time characteristics of the disposable soft contact lenses created unprecedented difficulties to the medical surveillance of their wearers. Without the right assistance they tend to become careless regarding routine cleaning. They also feel free to buy less expensive lenses, to use saline instead of lens solutions, to violate the limits of wearing time and to extend the use over the sleeping period. Additionally, the aggressive marketing and the wide distribution of these lenses increase the chances that economically or educationally unprepared people will acquire them. The question that remains is: Is the present case an accidental event or an example of what is likely to happen in the future if the indiscriminate selling of disposable soft contact lenses continues to evolve?


Este é o relato de uma paciente do sexo feminino, de 19 anos, com ceratite bilateral por Acanthamoeba, devido ao uso de lentes de contato descartáveis, adquiridas em uma butique. Fez uso do mesmo par de lentes durante três meses, sem os cuidados adequados. Foi submetida a transplante penetrante de córnea e facectomia bilateral, além de trabeculectomia no olho direito. Quando vista pela última vez, os enxertos estavam transparentes, mas a visão de ambos os olhos não era satisfatória. Ela também apresentava glaucoma secundário bilateral, controlado precariamente com medicação tópica. Ocorre que, as características físicas e o regime de uso das lentes de contato gelatinosas descartáveis criam dificuldades adicionais para a vigilância médica dos seus usuários. Sem a assistência correta, eles relaxam com a rotina de limpeza, compram lentes mais baratas, usam soro fisiológico ao invés das soluções adequadas, violam os limites de uso e dormem com as mesmas. Além disso, o "marketing" agressivo e a ampla distribuição dessas lentes aumentam as chances de que pessoas, não preparadas econômica e educacionalmente, venham ter acesso às mesmas. A pergunta que fica é: Seria o presente caso um evento acidental ou um exemplo do que pode acontecer no futuro caso as lentes de contato descartáveis continuem sendo vendidas indiscriminadamente?


Subject(s)
Animals , Female , Humans , Young Adult , Acanthamoeba , Amebiasis/complications , Contact Lenses/adverse effects , Corneal Ulcer/parasitology , Marketing , Corneal Ulcer/complications , Corneal Ulcer/therapy , Young Adult
15.
Arq. bras. oftalmol ; 70(2): 343-346, mar.-abr. 2007. ilus
Article in Portuguese | LILACS | ID: lil-453180

ABSTRACT

Relatamos três casos de infecção corneana por Acanthamoeba sp em que foi possível detectar cistos do microorganismo com a técnica de citologia de impressão. Três pacientes encaminhados ao Laboratório de Doenças Externas Oculares em 2004 com alterações superficiais da córnea foram submetidos ao exame de citologia de impressão para investigação da presença de cistos de Acanthamoeba sp. Duas amostras foram obtidas da córnea de cada paciente e coradas com PAS, hematoxilina e Papanicolaou. Investigação microbiológica de rotina e cultura também foram realizadas após raspado da córnea. O cultivo das amostras e a citologia de impressão foram positivas para Acanthamoeba sp em todos os pacientes, ao passo que os raspados corados com Giemsa foram positivos em dois casos. A citologia de impressão revelou cistos de Acanthamoeba sp entre feixe de células epiteliais corneanas e como células isoladas. Foram observados cistos no epitélio de um dos pacientes com a citologia de impressão após três meses de tratamento, enquanto o raspado foi negativo. No exame anatomopatológico observaram-se cistos no epitélio e estroma de uma córnea receptora de um dos pacientes após transplante. Neste estudo, a citologia de impressão detectou com sucesso cistos de Acanthamoeba sp em pacientes com acometimento epitelial. Por tratar-se de método não invasivo, a técnica pode ser usada para facilitar o diagnóstico mais precoce da infecção por Acanthamoeba, sendo útil também no acompanhamento do tratamento da doença.


To describe three cases of corneal infection due to Acanthamoeba sp in which was possible to detect Acanthamoeba sp cysts by the corneal impression cytology technique. Three patients referred to the External Eye Disease Laboratory in 2004 with superficial corneal alterations were submitted to corneal specimen collection by impression cytology filter paper to investigate the presence of Acanthamoeba sp cysts. Two impression cytology samples were obtained from each patient and were stained by PAS, hematoxylin and Papanicolaou. Routine microbiological investigation and culture were also performed using corneal scraping. Positive culture and impression cytology for Acanthamoeba sp was observed in all patients while smears with Giemsa stain were positive in two. Impression cytology Acanthamoeba sp cysts were observed among sheets of corneal epithelial cells and as isolated cells. Cysts were also found in the superficial epithelium in one of these patients after treatment while corneal scraping did not reveal any cyst. Histopathology revealed cysts in the epithelium and stroma in a transplanted cornea in one of these patients. The first description of impression cytology as a diagnostic method for Acanthamoeba keratitis occurred recently. In this study corneal impression cytology detected Acanthamoeba sp cysts successfully in these patients with only superficial involvement. Impression cytology as a non invasive technique can be used to facilitate early recognition of Acanthamoeba infection playing a useful role in the follow-up of the disease.


Subject(s)
Humans , Animals , Acanthamoeba Keratitis/diagnosis , Acanthamoeba Keratitis/etiology , Acanthamoeba Keratitis/microbiology , Acanthamoeba Keratitis/parasitology , Acanthamoeba/isolation & purification , Contact Lenses, Hydrophilic/adverse effects , Cytodiagnosis/standards , Cytological Techniques/standards , Epithelium, Corneal/microbiology , Epithelium, Corneal/pathology , Staining and Labeling
16.
Article in Korean | WPRIM | ID: wpr-228599

ABSTRACT

PURPOSE: To report 4 cases of Acanthamoeba keratitis related to orthokeratology lens overnight wear. METHODS: Four patients had histories of overnight orthkeratology lens wear of 10 months to 3 years when they presented with corneal ulcers. RESULTS: The organism isolated by corneal scraping was Aanthamoeba. The patients were treated with polyhexamethylene biguanide (PHMB), and chlorhexidine, resulting in a resolution of ocular inflammation. CONCLUSION: The risk of Acanthamoeba keratitis as a potential complication of overnight orthkeratology should be considered.


Subject(s)
Acanthamoeba Keratitis , Acanthamoeba , Chlorhexidine , Humans , Inflammation , Ulcer
17.
Article in Korean | WPRIM | ID: wpr-221378

ABSTRACT

PURPOSE: To report a rare case of Acanthamoeba keratitis in both eyes related to cosmetic contact lenses. METHODS: A 17-year-old girl with a history of wearing cosmetic contact lenses presented with keratitis. She purchased cosmetic contact lenses on the internet, and used contact lens care system irregularly with tap water. RESULTS: After analysis of the corneal scraping, the contact lenses and the storage solution, the organism Acanthamoeba was identified. The patient was treated with polyhexamethylene biguanide (PHMB) and chlorhexidine for 3 months, and recovered with normal visual acuity. CONCLUSIONS: Poor hygiene and insufficient disinfection may be major risk factors for Acanthameoba keratitis in cosmetic contact lens wearers. The cosmetic contact lens user should receive professional advice before using these lenses, and this precaution must be communicated to the public.


Subject(s)
Acanthamoeba Keratitis , Acanthamoeba , Adolescent , Chlorhexidine , Contact Lenses , Disinfection , Female , Humans , Hygiene , Internet , Keratitis , Risk Factors , Visual Acuity , Water
18.
Article in Korean | WPRIM | ID: wpr-40723

ABSTRACT

Laboratory diagnostic methods, applied for the diagnosis of Acanthamoeba Keratitis, were evaluated for their usefulness in 16 patients of suspicious Acanthamoeba keratitis. Wet smear, Acridine orange(AO) stain, Gram stain and culture on nonnuturent agar plate were routinely used in all patients, and among them, and used saline of 7 contact lens not ideal for the corneal scraping specimens. AO and Gram stains were very useful in the identification of acanthamoeba, and culture on nonnutrient agar plates was essential to confirm this infection. Light and electron microscopic examinations were also useful in patients with negative results of ordinary diagnostic techniques. Suspicion of Acanthamoeba infection in patients that are recalcitrant to antibiotic treatment or related to contact lens wear, is the mont important step for the diagnosis of Acanthamoeba Keratitis. And also examination of corneal specimens by experienced observer is prerequisite for the accurate diagnosis of Acanthamoeba keratitis.


Subject(s)
Acanthamoeba , Acanthamoeba Keratitis , Agar , Clinical Laboratory Techniques , Coloring Agents , Diagnosis , Humans , Keratitis
19.
Article in Korean | WPRIM | ID: wpr-178981

ABSTRACT

This study was performed to investigate the biochemical properties of Acanthamoeba proteinase, its role in the pathogenesis of Acanthamoeba keratitis and the therapeutic effect of the homogenate of amniotic membrane as a proteinase inhibitors. Acanthamoeba castellanii isolated from the keratitis patient was cultured in PYG medium, in which the excretory and secretory products were analysed. The secretory proteinases of A. castellanii wre identified using in vitro azocasein assay, activity-PAGE, and various protein substrate degradation assays, and one of them was purified and characterized. The pruified secretory proteinase was a kind of serine proteinase. Its molecular weight was 105 kDa and optimal pH was 8.5. It was able to degrade the various protein substrates such as fibronectin, IgA, IgG, fibrinogen. The various proteinase ingibitors and the amniotic membrane homogenates were tested in vitro against the purified seirne proteinase. The amniotic membrane homegenates markedly showed the inhibitory effect against the enzyme activity and this inhibitory effect was also revealed in animal study. In vivo study, this purified proteinase was infected into 14 pigmented rabbit corneas, pretreated with steroids. The corneal lesions induced by both of the purified proteinase and A. castellanii, showed similar clinical findings each other, in which the stromal infiltration and opacity with epithelial defect was revealed. These corneal lesions were significantly inhibited without any side effects of the amniotic membrane homogenates. Conclusively, Acanthamoeba proteinase was closely associated with the pathogenesis of Acanthamoeba keratitis. This study provides a successful animal model of Acanthamoeba keratitis using pigmented rabbit. And the fact that Acanthamoeba-induced corneal lesions were inhibited by the amniotic membrane homogenate, suggested that the amniotic membrane homogenate have the ability of the serine protinase inhibition further investigative studies are also necessary.


Subject(s)
Acanthamoeba castellanii , Acanthamoeba Keratitis , Acanthamoeba , Amnion , Animals , Cornea , Fibrinogen , Fibronectins , Humans , Hydrogen-Ion Concentration , Immunoglobulin A , Immunoglobulin G , Keratitis , Models, Animal , Molecular Weight , Peptide Hydrolases , Serine , Serine Proteases , Steroids
20.
Article in Korean | WPRIM | ID: wpr-161685

ABSTRACT

Acanthamoeba keratitis is uncommon and rarely reported in Korea. It has been reported in world literature as a very severe, progressive necrotizing stromal keratitis due to a non-parasitic free-living amoeba. It is frequently associated with minimal corneal trauma especially from contact lens but sometimes occurs in patients without any past history. We report a case of acanthamoeba keratitis without a specific past history in a 42-year-old man. Light and electron microscopy demonstrated severe stromal keratitis with numerous thick-walled cysts, 10~15 m in diameter, scattered in the superficial and deep stroma. Because this keratitis is most often mistaken for fungal, bacterial or herpetic keratitis, early confirmatory diagnosis by direct smear, biopsy or culture is essentially required for the prevention of visual loss or devastating eyeball loss.


Subject(s)
Acanthamoeba Keratitis , Acanthamoeba , Adult , Amoeba , Biopsy , Diagnosis , Humans , Keratitis , Keratitis, Herpetic , Korea , Microscopy, Electron
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