Molecular characterization of bacterial, viral and fungal endosymbionts of Acanthamoeba isolates in keratitis patients of Iran.

Free-living amoebae belong to the genus Acanthamoeba; can feed on microbial population by phagocytosis, and with the capability to act as a reservoir and a vehicle of microorganisms to susceptible host. Therefore, the role of endosymbiosis in the pathogenesis of Acanthamoeba is complex and not fully understood. The aim of the present study was to identify bacterial, fungal, and human adenovirus (HADV) endosymbionts as well as evaluating the endosymbionts role of such organisms in the pathogenesis of Acanthamoeba in keratitis patients living in Iran. Fifteen Acanthamoeba (T4 genotype) isolates were recovered from corneal scrapes and contact lenses of patients with keratitis. Cloning and purification was performed for all isolate. Gram staining was performed to identify bacterial endosymbionts. DNA extraction, PCR, and nested PCR was set up to identify endosymbiont of amoeba. Evaluation of pathogenicity was conducted by osmo-tolerance and thermo-tolerance assays and cell culture, and then CPE (cytopathic effect) was survey. Statistical analysis was used between Acanthamoeba associated endosymbionts and Acanthamoeba without endosymbiont at 24, 48, 72, and 96 h. A p value < 0.05 was considered as significant, statistically. A total of 9 (60%) Acanthamoeba (T4 genotypes) isolates were successfully cloned for detecting microorganism endosymbionts. The only isolate negative for the presence of endosymbiont was ICS9. ICS7 (Pseudomonas aeruginosa, Aspergillus sp., and human adenovirus endosymbionts) and ICS2 (Escherichia coli endosymbiont) isolates were considered as Acanthamoeba associated endosymbionts. ICS7 and ICS2 isolates were highly pathogen whereas ICS9 isolate showed low pathogenicity in pathogenicity evaluated. Positive CPE for ICS7 and ICS2 isolates and negative CPE for ICS9 isolate were observed in cell culture. The average number of cells, trophozoites, and cysts among ICS7, ICS2, and ICS9 isolates at 24, 48, 72, and 96 h was significant. This is the first survey on microbial endosymbionts of Acanthamoeba in keratitis patients of Iran, and also the first report of Aspergillus sp, Achromobacter sp., Microbacterium sp., Brevibacillus sp, Brevundimonas sp and Mastadenovirus sp in Acanthamoeba as endosymbionts. Our study demonstrated that microbial endosymbionts can affect the pathogenicity of Acanthamoeba; however, further research is required to clarify the exact pattern of symbiosis, in order to modify treatment protocol.

Case Report: Corneal Coinfection with Fungus and Amoeba: Report of Two Patients and Literature Review.

We report two cases of corneal coinfection with Acanthamoeba and Fusarium sp. along with the review of published literature. A 35-year-old woman and 65-year-old man presented to the institute with corneal ulcer refractory for treatment with topical antibiotics. Microbiological examination revealed the presence of Acanthamoeba cysts along with septate, hyaline fungal filaments. After emergency therapeutic penetrating keratoplasty (TPK) in both, the corneal tissue was sent for histopathologic examination, which confirmed the presence of Acanthamoeba and fungal coinfection. One patient had a recurrence of fungal infection after TPK. In subjects with a rapid progression of mycotic ulcer, coinfection with other microorganisms including Acanthamoeba should be suspected. The two cases presented here emphasize the importance of microbiology in making prompt diagnosis and appropriate management of these cases at an early stage.

Acanthamoeba keratitis in 194 patients: risk factors for bad outcomes and severe inflammatory complications.

BACKGROUND/AIMS: To determine demographic and clinical features of patients with Acanthamoeba keratitis (AK) that are independent risk factors both for bad outcomes and for severe inflammatory complications (SIC). METHODS: A retrospective audit of medical records of AK cases at Moorfields Eye Hospital from July 2000 to April 2012, including 12 earlier surgical cases. Cases with a bad outcome were defined as those having one or more of the following: corneal perforation, keratoplasty, other surgery (except biopsy), duration of antiamoebic therapy (AAT) ≥10.5 months (the 75th percentile of the whole cohort) and final visual acuity ≤20/80. SICs were defined as having scleritis and/or a stromal ring infiltrate. Multivariable analysis was used to identify independent risk factors for both bad outcomes and SICs. RESULTS: Records of 194 eyes (194 patients) were included, having bad outcomes in 93 (48%). Bad outcomes were associated with the presence of SIC, aged >34 years, corticosteroids used before giving AAT and symptom duration >37 days before AAT. The development of SIC was independently associated with aged >34 years, corticosteroids used before giving AAT and herpes simplex virus (HSV) keratitis treatment before AAT. CONCLUSIONS: The prompt diagnosis of AK, avoidance of a misdiagnosis of HSV keratitis and corticosteroid use before the exclusion of AK as a potential cause of keratitis are essential to the provision of a good outcome for patients and for the avoidance of SIC. Older age is an unmodifiable risk factor that may reflect differences in the immune response to AK in this patient subset.

[Acanthamoeba keratitis]. / Kératites amibiennes.

Early diagnosis and appropriate therapy are key elements for a good prognosis in Acanthamoeba keratitis (AK). AK should be considered in any case of corneal trauma complicated by exposure to soil or contaminated water, and in all contact lens (CL) wearers. A presumptive diagnosis of AK can be made clinically and with in vivo confocal microscopy, although a definitive diagnosis requires identification of Acanthamoeba on direct scraping, histology, or identification of Acanthamoeba DNA by polymerase chain reaction (PCR). We use cysticidal drugs for treating AK because encysted forms are more resistant than trophozoites to treatment. The treatment protocol used a biguanide (PHMB 0.02% or chlorhexidine 0.02%) and a diamidine (propamidine 0.1% or hexamidine 0.1%). New diagnostic modalities and more specific topical anti-amoebic treatments would substantially benefit patients with AK.

Failure of chemotherapy in the first reported cases of Acanthamoeba keratitis in Pakistan.

Acanthamoeba keratitis is a painful and progressive infection of the cornea that can result in loss of vision. Here, for the first time in Pakistan, we report two cases of Acanthamoeba keratitis. The first patient was a 37-year-old female who presented with severe itching, redness, pain, along with loss of vision. The patient was a regular soft contact lens wearer. The second patient was a 25-year-old female who had been using soft contact lenses for the past two years. She presented with a burning sensation and extreme pain, along with loss of vision. Both patients were treated for a possible microbial keratitis with topical moxifloxacin hydrochloride drops, vancomycin drops, propamidine isethionate ointment, amphotericin B drops, and amikacin drops. However, the response was inadequate and both patients were referred for corneal transplant. Acanthamoeba castellanii was isolated by placing contact lenses and contact lens cases on non-nutrient agar plates containing a lawn of non-invasive Escherichia coli K-12 HB101 bacteria. The polymerase chain reaction (PCR) using genus-specific probes confirmed the identity of Acanthamoeba spp., whereas the morphological characteristics of trophozoites and cysts were suggestive of A. castellanii in both cases. With growing use of contact lenses for vision correction/cosmetic use coupled with sub-standard lens care in this region and the possibility of non-contact lens-associated Acanthamoeba keratitis, a need for increased awareness of this sight-threatening infection is discussed further.

Scleral and intraocular amoebic dissemination in Acanthamoeba keratitis.

PURPOSE: To review an Acanthamoeba keratitis case series for the documented extracorneal spread of the amoeba. METHODS: A retrospective review of an observational case series from a single institution. RESULTS: Three patients with 4 instances of microbiologically confirmed extracorneal amoebic spread were identified. Patient 1 had nodular scleritis after undergoing penetrating keratoplasty and was treated successfully with double freeze-thaw cryotherapy; patient 2 had intraocular dissemination of the amoeba detected in a retrocorneal membrane; and patient 3 had, after undergoing tectonic keratoplasty, intraocular dissemination of the amoeba that was treated successfully with intraocular and systemic voriconazole and, afterwards, a nodular scleritis treated with double freeze-thaw cryotherapy and a large-diameter corneal graft to treat corneal recurrence. CONCLUSIONS: Acanthamoeba can migrate to the sclera or to the intraocular tissues in some instances, such as in long-standing disease or in penetrating keratoplasty. A prompt biopsy for microbiological analysis and early treatment are required, if this is suspected. Voriconazole can be effective for intraocular invasion when used orally and intraocularly. Scleral involvement might require a surgical approach with double freeze-thaw cryotherapy to treat the localized disease.

Coinfection with Acanthamoeba and Pseudomonas in contact lens-associated keratitis.

PURPOSE: To report coinfection with Acanthamoeba and Pseudomonas aeruginosa in a case with contact lens-associated keratitis. CASE REPORT: A 20-year-old woman presented to the emergency department of our hospital with a 4-day history of progressively increasing pain, redness, photophobia, mucopurulent discharge, and diminution of vision in her right eye. She was being treated for contact lens-related Pseudomonas keratitis in another hospital before presentation. Gram stain of corneal scrapings revealed gram-negative bacilli. Both Gram stain and 10% KOH wet mount showed the presence of Acanthamoeba cysts. Microbiological cultures obtained from contact lenses and contact lens storage case showed the presence of Pseudomonas aeruginosa and Acanthamoeba. Topical therapy was started in the form of hourly gentamycin 1.3%, cefazolin 5%, chlorhexidine 0.02%, propamidine 0.1%, polymyxin B 30,000 IU eye drops, and neosporin (neomycin, bacitracin, polymyxin) eye ointment four times a day. Symptomatic improvement was observed within 48 hours, along with a decrease in the density of infiltrates and a reduction in the anterior chamber reaction. Repeat corneal scrapings on day 10 showed Acanthamoeba but no bacilli. Progressive resolution of the infiltrate was noted during the next few days. Epithelialization was complete by day 24, following which the amoebicidal therapy was tapered during the next 4 weeks. Complete resolution of keratitis was achieved after 7 weeks of treatment. CONCLUSIONS: Both P. aeruginosa and Acanthamoeba are potentially devastating causes of microbial keratitis. Our case highlights the importance of considering the possibility of a concurrent infection in cases with contact lens-related keratitis.

[Delayed course of Acanthamoeba keratitis]. / Protrahierter Verlauf einer Akanthamöbenkeratitis.

A 35-year-old male presented with corneal ulceration on the left eye with a history of treatment over several months. At the first visit in our department we saw an elliptically shaped ulcerative stromal keratitis with circular peripheral neovascularization. There was organized hypopyon with hyphemia. The best corrected visual acuity (BCVA) was light perception. The patient had used contact lenses for many years. Under the suspicion of herpetic keratitis due to a positive "dendrite" the patient had undergone antiviral therapy for 6 months in a different department. Our diagnosis was Acanthamoeba keratitis. We performed penetrating excimer laser keratoplasty-à-chaud (8.0 × 7.0 mm/8.1 × 7.1 mm) with simultaneous cryotherapy of the mid-peripheral cornea. The topical therapy was polyhexamethylene biguanide, propamidine isoethionate, neomycin and steroids in intervals. A repeat penetrating excimer laser keratoplasty (8.5 × 7.5 mm/8.6 × 7.6 mm) with simultaneous amniotic membrane patch and lateral tarsorrhaphy was performed 2 months later due to melting of the graft with positive Seidel test. After successful surgery of the mature cataract the BCVA was 20/25. In a patient with a positive contact lens history acanthamoeba keratitis should always be considered as a differential diagnosis to herpes simplex keratitis in the early course of the disease.

A case of sympathetic ophthalmia after a severe acanthamoeba keratitis.

PURPOSE: To report a case of sympathetic ophthalmia (SO) after a severe Acanthamoeba keratitis. METHODS/DESIGN: Interventional case report. RESULTS: A 59-year-old white woman, wearing contact lenses, developed a severe Acanthamoeba keratitis in the left eye, which involved the limbus, and required 8 months of intensive antiamoeba therapy; the condition resolved leaving a painful, phthisical eye with complete corneal neovascularization. Six months later, the patient presented with pain, blurred vision, and photophobia in the right eye. Slitlamp examination of the right eye revealed granulomatous uveitis. On the suspicion of an SO, treatment with high-dose topical and oral corticosteroids and immunosuppressants was started. After 3 months, the eye is stable, with a visual acuity of 20/50, and the patient is taking prednisolone 7.5 mg per day and cyclophosphamide 50 mg per day. CONCLUSIONS: [corrected] Development of SO in the absence of previous trauma or surgery is rare. Our case is the first report of a clinically diagnosed SO after an episode of severe Acanthamoeba keratitis.

An atypical presentation of acanthamoeba keratitis in a patient with keratoconus treated briefly with topical anesthetic.

OBJECTIVES: To present a case of biopsy proven acanthamoeba keratitis requiring penetrating keratoplasty in a patient with keratoconus whose clinical course was remarkable for its lack of ocular injection and pain. The absence of these key findings may have contributed to a delay in diagnosis and a delay in instituting antiamoebic therapy. METHODS: Case report. RESULTS: A 21-year-old woman who wore soft contact lenses for management of keratoconus presented with a painful suppurative corneal infiltrate and epithelial defect. The patient was initially seen in an emergency department where she was given a bottle of topical anesthetic drops (proparacaine) to use for pain. When she was seen by the authors 18 hr after presenting to the emergency department, the proparacaine was immediately discontinued, and she was treated with fortified antibiotic (vancomycin and tobramycin) eye drops and oral antiviral medications (famciclovir). Despite an initial improvement and complete resolution of ocular discomfort, the patient went on to develop a dense, peripheral stromal infiltrate that failed to improve despite intensive treatment. Confocal microscopy and corneal biopsy were definitive for acanthamoeba infection. The patient subsequently failed medical therapy and underwent large diameter penetrating keratoplasty. The patient has shown no evidence of acanthamoeba recurrence in the corneal graft. CONCLUSIONS: Keratoconic patients may have atypical presentations of acanthamoeba keratitis, which may delay diagnosis and institution of medical therapy. Even brief use of topical anesthetics may further complicate the clinical picture.

Acanthamoeba sclerokeratitis.

BACKGROUND: Acanthamoeba scleritis is an uncommon but severe complication of acanthamoeba keratitis. We report the clinical and histopathologic features of a patient with acanthamoeba sclerokeratitis. METHODS: Review of the patient's clinical records and histopathologic examination of the globe including light microscopy and transmission electron microscopy. RESULTS: Review of the clinical record of the patient revealed a past ocular history of penetrating keratoplasty for persistent acanthamoeba keratitis. Later in the course of treatment, the patient developed nodular necrotizing scleritis with culture-proven viable acanthamoeba in this area. She underwent enucleation of the eye for persistent acanthamoeba sclerokeratitis. Histopathologic examination of the globe revealed no acanthamoeba cysts or trophozoites at the site of crotherapy. CONCLUSION: Our study provides evidence for the invasion of acanthamoeba organisms into the sclera in a case of acanthamoeba keratitis. The presence of trophozites in scleral tissue may exacerbate the immune response leading to nodular scleritis.

Contact lens-related acanthamoeba keratitis in a patient with chronic fatigue syndrome.

PURPOSE: To report a case of contact lens-related Acanthamoeba keratitis associated with improper lens hygiene in a patient with chronic fatigue syndrome (CFS). METHODS: Contact lens-related Acanthamoeba keratitis was diagnosed in a 58-year-old man with a history of CFS. After medical management failed to prevail, a penetrating keratoplasty was performed in the affected eye. RESULTS: There was no recurrence of Acanthamoeba keratitis after surgery. Complete re-epithelialization of the graft was observed with a best-corrected visual acuity of 20/80 in the operated eye at the last follow-up (3 months). CONCLUSIONS: Our case report highlights the fact that concurrent incapacitating illnesses like CFS may not allow proper care of contact lenses thereby making patients prone to contact lens-related corneal infections.

Acanthamoeba keratitis--importance of the early diagnosis.

This is a case report of Acanthamoeba as a causative agent of keratitis at the Department of Ophthalmology, University Hospital Rijeka. Delay in treatment led to an advanced stage of the disease with multiple complications. Initially, presented symptoms were similar to those of herpetic keratitis. In the mean time progression of the disease led to a cloudy cornea with a stromal ring infiltrate, poor vision, elevated intraocular pressure, a mature cataract and finally corneal melt. Corneal scrapings were obtained from a 28 years old female patient, wearing soft contact lenses and with poor lens hygiene. Acanthamoeba cysts were identified by the cytological examination. Culture of the corneal scraping had confirmed Acanthamoeba as the etiological agent. Making the diagnosis of Acanthamoeba is difficult. We presented this case of delayed diagnosis and unfavorable outcome as a reminder that clinical suspicion remains the most important diagnostic tool. Contact lens wears with a new diagnosis of herpes simplex keratitis are in high risk group, especially those with significant pain or poor response to conventional therapy. We also wanted to point out the possibility of an early, prompt and inexpensive diagnosis with the cytological examination.

[Acanthamoeba keratitis: about the first two Tunisian cases]. / Les kératites amibiennes: à propos des deux premiers cas tunisiens.

Acanthamoeba keratitis is a rare but severe corneal infection which, despite improvements in diagnosis and treatment, still culminates in prolonged morbidity and significant loss of visual acuity. We present the case report of the first identification of Acanthamoeba as a causative agent of keratitis in Tunisia. Case no 1: A 20-year-old girl, nearsighted corrected with soft contact lenses, suffering from a deep corneal inflammation and poor visual acuity The ophthalmological examination showed bilateral dendritiform epithelial keratitis. The illness did not respond to topical and general antibiotic treatment and developed bilateral corneal abscess. Microscopic examination and culture of samples from cornea scraping revealed the presence of trophozoit and cysts of Acanthamoeba associated with Fusarium oxysporum. As the treatment with local Ketoconazol and antibiotherapy didn't show any result, two transfixiant keratoplasty were carried out and treatment by Désomédine, PHMB (polyhexamethylene biguanide) and Voriconazol was started. After two months, the patient felt better, vision was also improved (2/10) and infiltrates became smaller Case no 2: A 19-year-old girl, nearsighted with soft contact lenses consulted for a bilateral corneal ulceration and poor vision (1/20). Trophozoit and cysts of Acanthamoeba were found in the contact lens solution. She was treated quickly with Désomédine. Visual acuity improved to 7/10 but the corneal ulceration left a residual opacity

A study of the spectrum of Acanthamoeba keratitis: a three-year study at a tertiary eye care referral center in South India.

PURPOSE: To determine the epidemiological and clinical characteristics of Acanthamoeba keratitis and also to determine the sensitivity and specificity of smears in the detection of Acanthamoeba. MATERIALS AND METHODS: A retrospective review of all culture-positive cases of Acanthamoeba keratitis seen between October 1999 and August 2002 was performed. Corneal scrapes were subjected to culture and microscopy using standard protocols. RESULTS: Out of 3183 consecutive patients with clinically diagnosed corneal ulcers evaluated, 33 (1.04%) were found to be due to Acanthamoeba. Twenty-four out of 33 (72.72%) were less than 51 years of age (P<0.001). All patients were from rural areas (P<0.001) and 26 (78.79%) of them were agricultural workers (P=0.031). All 33 had history of corneal injury (P<0.001) and 28 (84.85%) patients had injury with mud (P<0.001). All 33 (100%) patients had previous medical treatment (P=0.009) and 10 (30.3%) had used traditional eye medicines (P=0.183). A clinical pattern of ring infiltrate was characteristic in 15 (45.45%) patients. The diameter of the corneal ulcer was more than 6 mm in 27 (81.82%) eyes (P<0.001). Twenty-six (78.79%) patients had visual acuity of perception of light on initial presentation (P<0.001) and 24 (72.73%) had the same as their final visual outcome. The sensitivity of 10% potassium hydroxide (KOH) preparation was found to be higher (P<0.001) in the detection of Acanthamoeba cysts. CONCLUSION: The incidence of Acanthamoeba keratitis amongst the corneal ulcer patients was 1% in this setting and it was mainly due to corneal injury by mud. The KOH preparation is a sensitive diagnostic tool for the detection of Acanthamoeba. Delayed diagnosis or misdiagnosis and inappropriate antimicrobial therapy results in poor visual outcome.

Severe reactive ischemic posterior segment inflammation in acanthamoeba keratitis: a new potentially blinding syndrome.

OBJECTIVE: To describe a newly recognized clinical syndrome in Acanthamoeba keratitis consisting of severe reactive ischemic posterior segment vascular inflammation. DESIGN: Noncomparative, retrospective, single-institution observational case series. PARTICIPANTS: Five eyes of 5 patients with Acanthamoeba keratitis. METHODS: A retrospective review of the records of patients diagnosed with Acanthamoeba keratitis between January 1, 1995, and December 1, 2005, was conducted to identify those who underwent eventual enucleation. Five enucleated eyes of 118 eyes with Acanthamoeba keratitis were identified. MAIN OUTCOME MEASURES: History, clinical examination results, available laboratory study results, and histopathologic examination results. RESULTS: Histopathologic examination showed Acanthamoeba cysts in the cornea in 4 eyes, whereas it failed to demonstrate amebic cysts or trophozoites in the posterior segment of all eyes studied and unexpectedly revealed chronic chorioretinal inflammation with perivascular lymphocytic infiltration and diffuse neuroretinal ischemia in 4 of 5 eyes. Retinal artery thrombosis was present in 3 of the 4 involved eyes, and central retinal artery and vein thrombosis was found in 1 eye. Hematologic studies in 3 patients showed abnormal anticardiolipin antibody levels in 1 patient and factor V Leiden deficiency in another. CONCLUSIONS: Prolonged Acanthamoeba keratitis can result in a severe sterile ischemic posterior segment inflammation that is potentially blinding, especially in patients with underlying hypercoagulation disorders.

Secondary glaucoma associated with advanced acanthamoeba keratitis.

PURPOSE: To describe the association of acanthamoeba keratitis and glaucoma, to establish an incidence of glaucoma in patients with acanthamoeba keratitis, to discuss treatment options and outcomes in these patients, and to describe the histopathologic findings and pathogenesis of glaucoma secondary to acanthamoeba keratitis. METHODS: After Institutional Review Board approval, the charts of all patients suspected of having acanthamoeba keratitis at Aston Ambulatory Center at The University of Texas Southwestern Medical Center were reviewed. Inclusion criteria were as follows: diagnosis of acanthamoeba keratitis by positive confocal microscopy or culture, diagnosis of glaucoma or ocular hypertension secondary to acanthamoeba keratitis, and at least 6 months of follow-up. Exclusion criteria included a previous diagnosis of glaucoma or ocular hypertension and any history of intraocular surgery before the development of glaucoma. The date of keratitis development, pneumotonometry on initial and follow-up examinations, glaucoma medications used, and surgical procedures performed were tabulated. RESULTS: Twenty patients (20 eyes) were included. Six (30%) eyes developed secondary glaucoma during the review period. Of the patients treated for glaucoma with medication alone, the visual acuity of three (75%) of four became light perception or no light perception. Three of six patients required glaucoma drainage device implantation for intraocular pressure control. Of these, the vision of one eye became no light perception, and the other two eyes maintained better than 20/100 vision. Histopathologic examination showed chronic inflammation of the trabecular meshwork and angle closure. No acanthamoeba organisms were found in the angle structures. CONCLUSIONS: The development of secondary glaucoma is not uncommon in acanthamoeba keratitis and is a poor prognostic sign in patients with acanthamoeba keratitis, because most progress to light perception or no light perception vision. Histopathologic findings suggest an inflammatory angle-closure mechanism, apparently without direct infiltration of the organism. The glaucoma associated with acanthamoeba keratitis is often severe and frequently requires surgical intervention for intraocular pressure control and vision preservation.

Combined acanthamoeba and Stenotrophomonas maltophilia keratitis treated with a conjunctival flap followed by penetrating keratoplasty.

PURPOSE: To describe whether a technique of treatment of a combined acanthamoeba-stenotrophomonas keratitis with a conjunctival flap followed by a penetrating keratoplasty is successful. METHODS: A case of chronic ring-shaped keratitis in which Stenotrophomonas maltophilia was isolated with corneal scrapings, and acanthamoeba cysts were found with a corneal biopsy. The infection was resistant to conventional medical treatment. It was treated with a conjunctival flap combined with corneal cryo treatment, followed by a penetrating keratoplasty 6 months later. RESULTS: The patient achieved immediate pain relief after the conjunctival flap. All medications were tapered off over 3 months. A penetrating keratoplasty was performed after 6 months. The cornea remained clear and the best-corrected visual acuity is 20/25 2 years after surgery. CONCLUSIONS: A combined acanthamoeba-stenotrophomonas keratitis, which is resistant to medical therapy, can be treated successfully with a conjunctival flap followed by a penetrating keratoplasty.

Acanthamoeba keratitis in a 5-year-old boy without a history of contact lens usage.

PURPOSE: This study was designed to report a case of acanthamoeba keratitis in a 5-year-old child without a history of trauma or contact lens usage. METHODS: The history, clinical presentation, diagnostic, and therapeutic approaches were reviewed. RESULTS: A 5-year-old child without any history of trauma or contact lens use was referred to our university clinic with an initial diagnosis of disciform herpetic keratitis. After 2 weeks of antibacterial and antiviral therapy, a corneal biopsy was performed for diagnostic purposes. The biopsy revealed acanthamoeba. Subsequently intensive therapy with chlorhexidine diacetate 0.02%, ketoconazole tb, hexamidine di-isethionate 0.1% was initiated. At the end of the first month, topical prednisolone acetate 1% was added to reduce inflammation, Chlorhexidine diacetate 0.02% and oral ketoconazole were discontinued, and hexamidine di-isethionate 0.1% was lowered to 4 x 1 and was administered for an additional 4 months. At the end of 5 months, all medications were withdrawn and amblyopia treatment was started. CONCLUSION: When dealing with keratitis in children, acanthamoeba should be considered even without history of contact lens usage or trauma.

Acanthamoeba keratitis in a non-contact lens wearer with human immunodeficiency virus.

Acanthamoeba keratitis is potentially blinding and often associated with contact lens wearing. A human immunodeficiency virus (HIV)-positive patient, a non-contact lens wearer, presented with keratitis. She experienced a protracted course of disease, characterized by exacerbations and remissions, and was treated with various topical antibiotics and steroids. 13 months after symptom onset the eye was removed owing to serious scarring of cornea and unbearable pain. Microbiological and histopathological examination of the cornea showed Acanthamoeba. In non-contact lens wearers suffering from Acanthamoeba keratitis the diagnosis is delayed, pathognomonic features are often not seen and visual outcome is usually poor. There is no known relation between HIV infection and Acanthamoeba keratitis.