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Mohanty A, Sahu SK, Sharma S, Mittal R, Behera HS, Das S, Lakhmipathy M. Past, present, and prospects in microsporidial keratoconjunctivitis- A review. Ocul Surf 2023; 28:364-377. [PMID: 34419638 DOI: 10.1016/j.jtos.2021.08.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 07/19/2021] [Accepted: 08/14/2021] [Indexed: 11/29/2022]
Abstract
Ocular microsporidiosis comprises two entirely different spectra of disease as keratoconjunctivitis and stromal keratitis. Microsporidial keratoconjunctivitis (MKC) has been increasingly reported in the past two decades, probably due to raised awareness, simpler diagnostic procedures, and a better understanding of the clinical presentation. It is characterized by the presence of raised, coarse, punctate, multifocal, round to oval, greyish-white corneal epithelial lesions which usually evolve into nummular scars before resolution. Conjunctivitis seen is non-purulent and of mild-moderate intensity, with mixed papillary-follicular reaction. The mode of transmission and pathogenesis is poorly understood. Despite lack of inflammatory response, uncommon associations reported were- endotheliitis, corneal edema, limbitis, uveitis, and sub-epithelial infiltrates. There has been no consensus on the management of MKC. It varies from the use of multiple antimicrobial agents to simple lubricants. The majority of the disease goes underdiagnosed or misdiagnosed and treated as adenoviral keratoconjunctivitis, with topical steroids or anti-virals empirically. Changing trends have been noticed in the pattern of infection, possibly with increasing evidence of Vittaforma corneae as causative organisms, previously reported to cause stromal keratitis. An elaborate review of the past and present literature on MKC is provided in this review article, along with gaps in knowledge, and future directions of research.
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Affiliation(s)
- Amrita Mohanty
- Cornea and Anterior Segment Services, L. V. Prasad Eye Institute, Mithu Tulsi Chanrai Campus, Bhubaneswar, Odisha, India
| | - Srikant K Sahu
- Cornea and Anterior Segment Services, L. V. Prasad Eye Institute, Mithu Tulsi Chanrai Campus, Bhubaneswar, Odisha, India.
| | - Savitri Sharma
- Jhaveri Microbiology Centre, L. V. Prasad Eye Institute, Kallam Anji Reddy Campus, Hyderabad, India
| | - Ruchi Mittal
- Kanupriya Dalmia Ophthalmic Pathology Laboratory, L.V. Prasad Eye Institute, Bhubaneswar, Odisha, India; Department of Pathology, Kalinga Institute of Medical Sciences, Bhubaneswar, Odisha, India
| | - Himansu Sekhar Behera
- Ocular Microbiology Service, L.V. Prasad Eye Institute, Mithu Tulsi Chanrai Campus, Bhubaneswar, Odisha, India
| | - Sujata Das
- Cornea and Anterior Segment Services, L. V. Prasad Eye Institute, Mithu Tulsi Chanrai Campus, Bhubaneswar, Odisha, India
| | - Meena Lakhmipathy
- Department of Cornea and Refractive Surgery, Medical Research Foundation, Sankara Nethralaya, Chennai, India
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Radhakrishnan N, Smit D, Venkatesh Prajna N, S R R. Corneal Involvement in HIV-infected Individuals. Ocul Immunol Inflamm 2021; 29:1177-1182. [PMID: 34232799 DOI: 10.1080/09273948.2021.1887283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Corneal involvement in HIV-infected individuals may be broadly classified into two categories, namely, infectious and noninfectious with the vast majority of manifestations occurring in the former. In this article, we shall focus on these two categories and strive to highlight those presentations that should alert the clinician to suspect underlying HIV infection. Infectious group mainly consists of Herpitic group of viral infections. Bacterial causes may be due to Staphylococcus epidermidis, Staphylococcus aureus, Pseudomonas aeroginosa, alpha hemolytic Streptococcus, Micrococcus and Bacillus. Fungalf keratitis in HIV-infected individuals depends on the geographic locations from which patient comes. Microsporidia and Acanthamoeba are common Protozoal causes. Non-infective inflammatory causes include peripheral ulcerative keratitis, keratoconjunctivitis sicca, and squamous cell carcinoma of the conjunctiva. Severity which is abnormally severe or very minimally reactive makes the clinician suspect of immunosuppression.
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Affiliation(s)
| | - Derrick Smit
- Department of Surgical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | | | - Rathinam S R
- Cornea and Refractive Surgery, Aravind Eye Care System, Madurai, India
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Abstract
Microsporidia are obligate intracellular pathogens identified ∼150 years ago as the cause of pébrine, an economically important infection in silkworms. There are about 220 genera and 1,700 species of microsporidia, which are classified based on their ultrastructural features, developmental cycle, host-parasite relationship, and molecular analysis. Phylogenetic analysis suggests that microsporidia are related to the fungi, being grouped with the Cryptomycota as a basal branch or sister group to the fungi. Microsporidia can be transmitted by food and water and are likely zoonotic, as they parasitize a wide range of invertebrate and vertebrate hosts. Infection in humans occurs in both immunocompetent and immunodeficient hosts, e.g., in patients with organ transplantation, patients with advanced human immunodeficiency virus (HIV) infection, and patients receiving immune modulatory therapy such as anti-tumor necrosis factor alpha antibody. Clusters of infections due to latent infection in transplanted organs have also been demonstrated. Gastrointestinal infection is the most common manifestation; however, microsporidia can infect virtually any organ system, and infection has resulted in keratitis, myositis, cholecystitis, sinusitis, and encephalitis. Both albendazole and fumagillin have efficacy for the treatment of various species of microsporidia; however, albendazole has limited efficacy for the treatment of Enterocytozoon bieneusi. In addition, immune restoration can lead to resolution of infection. While the prevalence rate of microsporidiosis in patients with AIDS has fallen in the United States, due to the widespread use of combination antiretroviral therapy (cART), infection continues to occur throughout the world and is still seen in the United States in the setting of cART if a low CD4 count persists.
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Mohanty A, Mitra S, Mallick A, Barik MR, Das S, Priyadarshini S, Sahu SK. Sequelae of microsporidial keratoconjunctivitis and its management. Indian J Ophthalmol 2021; 69:1537-1543. [PMID: 34011737 PMCID: PMC8302272 DOI: 10.4103/ijo.ijo_1971_20] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Purpose: To characterize the sequelae of microsporidia keratoconjunctivitis (MKC) and outline its management. Methods: Retrospective analysis of microbiologically proven MKC returned with persistent disease between January 2015 and December 2019 was done. Demographics, clinical features, management, and outcome were analyzed. Results: Sixteen patients (21 eyes) of 332 treated for MKC returned with the persisting disease. The mean age of 11 males (68.7%), and 5 females was 35.1 ± 12.2 years. Three-quarter of them did not have a known predisposing risk factor and one-quarter of them were referred for chronic conjunctivitis. Past medications included topical antivirals (n = 8) and topical corticosteroid (n = 6). Three predominant presentations were persistent (>3 weeks) superficial punctate keratitis (SPKs, n = 7), sub-epithelial infiltrates (SEIs, n = 13), and uveitis (n = 2). The lesions recurred in eight eyes (SPK and SEI 4 each) after a disease-free interval of 60.4 ± 40.6 days; there were 13 episodes of recurrence. Topical low potent corticosteroids (loteprednol/fluorometholone), and tacrolimus ointment 0.03% were used in 17 (80.9%) and 8 (38%) eyes, respectively, for a mean duration of 44.8 ± 31.6 and 226.8 ± 180.5 days, respectively. At follow-up, 172.3 ± 183.6 days, visual recovery was statistically significant in persistent eyes (BCVA 0.07 ± 0.07 logMAR; P < 0.00001) but, not in recurrent eyes (BCVA 0.16 ± 0.08 logMAR; P = 0.07). Five of 21 eyes were left with residual significant scar. Conclusion: The sequelae of microsporidial keratoconjunctivitis are not uncommon. Topical 0.03% tacrolimus ointment appeared to be an effective corticosteroid-sparing agent for the treatment of SEIs and prevention of recurrence.
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Affiliation(s)
- Amrita Mohanty
- Cornea and Anterior Segment Services, Mithu Tulsi Chanrai Campus, L.V. Prasad Eye Institute, Bhubaneswar, Odisha, India
| | - Sanchita Mitra
- Ocular Microbiology Service, Mithu Tulsi Chanrai Campus, L.V. Prasad Eye Institute, Bhubaneswar, Odisha, India
| | - Aparajita Mallick
- Ocular Microbiology Service, Mithu Tulsi Chanrai Campus, L.V. Prasad Eye Institute, Bhubaneswar, Odisha, India
| | - Manas Ranjan Barik
- Ocular Microbiology Service, Mithu Tulsi Chanrai Campus, L.V. Prasad Eye Institute, Bhubaneswar, Odisha, India
| | - Sujata Das
- Cornea and Anterior Segment Services, Mithu Tulsi Chanrai Campus, L.V. Prasad Eye Institute, Bhubaneswar, Odisha, India
| | - Smrutirekha Priyadarshini
- Cornea and Anterior Segment Services, Mithu Tulsi Chanrai Campus, L.V. Prasad Eye Institute, Bhubaneswar, Odisha, India
| | - Srikant K Sahu
- Cornea and Anterior Segment Services, Mithu Tulsi Chanrai Campus, L.V. Prasad Eye Institute, Bhubaneswar, Odisha, India
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Alkatan HM, Al-Essa RS. Challenges in the diagnosis of microbial keratitis: A detailed review with update and general guidelines. Saudi J Ophthalmol 2019; 33:268-276. [PMID: 31686969 PMCID: PMC6819704 DOI: 10.1016/j.sjopt.2019.09.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Revised: 08/31/2019] [Accepted: 09/02/2019] [Indexed: 11/04/2022] Open
Abstract
The incidence of microbial keratitis (MK) is variable worldwide with an estimated 1.5–2 million cases of corneal ulcers in developing countries. The complications of MK can be severe and vision threatening. Therefore, proper diagnosis of the causative organism is essential for early successful treatment. Accurate sampling of microbiological specimens in MK is an important step in identifying the infective organism. Corneal scrapping, tear samples and corneal biopsy are examples of specimens obtained for the investigative procedures in MK. Ophthalmologists especially in an emergency room setting should be aware of the proper sampling techniques based on their microbiology-related basic information for each category of MK. This review article briefly describes the clinical presentation and defines in details the best updated diagnostic methods used in different types of MK. It can be used as a guide for ophthalmology trainees and general ophthalmologists who may be handling such cases at initial presentation.
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Affiliation(s)
- Hind M Alkatan
- Department of Ophthalmology, College of Medicine, King Saud University-Medical City, Riyadh, Saudi Arabia.,Department of Pathology, College of Medicine, King Saud University-Medical City, Riyadh, Saudi Arabia
| | - Rakan S Al-Essa
- Department of Ophthalmology, College of Medicine, King Saud University-Medical City, Riyadh, Saudi Arabia
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Mittal R, Balne PK, Sahu S, Das S, Sharma S. Coexistence of herpes simplex virus infection in microsporidial stromal keratitis associated with granulomatous inflammation. Indian J Ophthalmol 2017; 65:276-281. [PMID: 28513490 PMCID: PMC5452578 DOI: 10.4103/ijo.ijo_761_15] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Background: Microsporidial stromal keratitis poses several diagnostic challenges. Patients may present with corneal ulceration, marked stromal thinning, or even as a quite corneal scar. The presentation of microsporidial stromal keratitis commonly mimics viral keratitis. Microbiology scrapings are usually helpful; however, scraping and culture-negative cases pose a significant diagnostic dilemma. Histopathological examination is diagnostic but shows varying degree of inflammation, predominantly composed of polymorphonuclear leukocytes. Granulomatous inflammation, in microsporidial stromal keratitis, is never well described, and the authors in this article aim to describe the presence of granulomatous inflammation in microsporidial stromal keratitis, in patients with associated herpes simplex virus (HSV) keratitis. Methods: This was a retrospective and observational study conducted at a tertiary eye care center. Results: Of 263 patients who underwent therapeutic penetrating keratoplasty for infectious keratitis, during 2011–2013, seven patients were diagnosed as microsporidial stromal keratitis. Microsporidial spores could be demonstrated on microbiological scrapings in 5/7 (71%) of cases, but identified on histopathological examination and also confirmed on polymerase chain reaction (PCR) for microsporidium in 100% of cases. There was evidence of diffuse stromal necrosis with markedly severe degree of polymorphonuclear leukocytic infiltrates, with granulomatous inflammation in 42% of cases. Interestingly, these were positive for HSV-1 DNA on PCR. Review of medical records revealed much severe clinical presentations in patients with granulomatous inflammation, in comparison to cases without granulomatous inflammation. Conclusions: The authors hereby recommend that severe clinical presentation in patients with microsporidial stromal keratitis, markedly dense polymorphonuclear leukocytic infiltrates or the presence of granulomatous inflammation on the histopathological examination, should be investigated further for the presence of HSV-1 DNA for better patient management and good visual outcome.
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Affiliation(s)
- Ruchi Mittal
- Dalmia Ophthalmic Pathology Services, L. V. Prasad Eye Institute, Bhubaneswar, Orissa, India
| | - Praveen K Balne
- Ocular Microbiology Services, L. V. Prasad Eye Institute, Bhubaneswar, Orissa; Jhaveri Microbiology Centre, L. V. Prasad Eye Institute, Hyderabad, Telangana, India
| | - Srikant Sahu
- Department of Cornea and Anterior Segment Services, Tej Kohli Cornea Institute, L. V. Prasad Eye Institute, Bhubaneswar, Orissa, India
| | - Sujata Das
- Department of Cornea and Anterior Segment Services, Tej Kohli Cornea Institute, L. V. Prasad Eye Institute, Bhubaneswar, Orissa, India
| | - Savitri Sharma
- Ocular Microbiology Services, L. V. Prasad Eye Institute, Bhubaneswar, Orissa; Jhaveri Microbiology Centre, L. V. Prasad Eye Institute, Hyderabad, Telangana, India
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Fan NW, Lin PY, Chen TL, Chen CP, Lee SM. Treatment of microsporidial keratoconjunctivitis with repeated corneal swabbing. Am J Ophthalmol 2012; 154:927-933.e1. [PMID: 22959880 DOI: 10.1016/j.ajo.2012.06.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2012] [Revised: 06/10/2012] [Accepted: 06/13/2012] [Indexed: 02/02/2023]
Abstract
PURPOSE To report the effect of repeated corneal swabbing in patients with microsporidial keratoconjunctivitis. DESIGN Retrospective noncomparative case series. METHODS Sixteen eyes of 14 healthy patients with microsporidial keratoconjunctivitis were diagnosed based on the detection of microsporidia in corneal scrapings using Gram stain, the modified Kinyoun acid-fast stain, or both. Polymerase chain reaction plus gene analysis of the microsporidian 16S ribosomal RNA had been performed in 10 patients who sought treatment between 2010 and 2011. Some of the lesions were scraped for procurement of specimens. The remaining lesions were wiped off gently by cotton swabs. Repeated swabbing was performed if infection persisted or new lesions were observed at follow-up. To prevent secondary bacterial infection, 0.3% norfloxacin or 0.25 % chloramphenicol were prescribed. RESULTS The mean age was 52.2 years. All patients had the characteristic disseminated, punctate, slightly elevated, white epithelial lesions. The denser white lesions could be removed easily after gentle swabbing, and most epithelium remained intact. The 10 cases with positive polymerase chain reaction results were all identified to be Vittaforma corneae. The mean number of corneal swabbing was 3.3, and the mean disease resolution time was 6.6 days. No patients had recurrence or loss of visual acuity at last follow-up. CONCLUSIONS Repeated swabbing effectively can eradicate corneal epithelial microsporidial lesions in approximately 1 week. It is easy to perform, less painful, and more acceptable for the patients.
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Affiliation(s)
- Nai-Wen Fan
- Department of Ophthalmology, Taipei Veterans General Hospital, Taipei, Taiwan
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Alkatan HM, Al-Zaaidi S, Athmanathan S. Microsporidial keratitis: Literature review and report of 2 cases in a tertiary eye care center. Saudi J Ophthalmol 2012; 26:199-203. [PMID: 23960992 DOI: 10.1016/j.sjopt.2012.02.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Accepted: 02/08/2012] [Indexed: 11/24/2022] Open
Abstract
Microsporidia are getting more recognized as causative organism of ocular, gastrointestinal, renal, pulmonary, and sinus diseases, in both immunocompetent and immunosuppressed patients. Ocular microsporidiosis can be isolated or may present as part of systemic infection. Recent reports showed increasing number of cases of ocular microsporidiosis in immunocompetent individuals. The ocular type occurs mainly in two forms: keratoconjunctivitis form which is mostly seen in immunocompromised individuals and stromal keratitis form seen in immunocompetent individuals. The ocular cases which present with superficial keratitis in acquired immune deficiency syndrome (AIDS) patients differ from the cases seen in immunocompetent individuals which present mainly as deep stromal keratitis. We are presenting the only two documented cases of microsporidial keratitis diagnosed over 25 years of practice in our institution. The cases are diagnosed by identification of the Acid-fast organisms. Ultrastructure and additional information on species identification in one of the cases. Both cases are eventually managed by therapeutic PKP. Diagnosis and treatment modalities are discussed based on a comprehensive literature review.
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Affiliation(s)
- Hind M Alkatan
- Pathology and Laboratory Medicine Department, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia
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Abstract
This retrospective study included 10 eyes of 9 patients diagnosed with microsporidial keratitis. All of them were known to contract this disease after taking baths in hot springs. The disease was diagnosed based on detecting microsporidia in corneal scrapings using Gram stain and the modified Kinyoun's acid-fast stain. The specimens from the last six patients were subjected to PCR and then sequencing. All of them revealed that the microorganism identified has a high similarity to Vittaforma corneae. Repeated debridement of the epithelial lesions successfully eradicated the microsporidial infection in all nine patients.
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Sharma S, Das S, Joseph J, Vemuganti GK, Murthy S. Microsporidial Keratitis: Need for Increased Awareness. Surv Ophthalmol 2011; 56:1-22. [DOI: 10.1016/j.survophthal.2010.03.006] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2009] [Revised: 03/24/2010] [Accepted: 03/30/2010] [Indexed: 12/24/2022]
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Hood CT, Jeng BH, Lowder CY, Holland GN, Meisler DM. Corneal and External Ocular Infections in Acquired Immunodeficiency Syndrome (AIDS). Cornea 2011. [DOI: 10.1016/b978-0-323-06387-6.00074-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Jeng BH, Holland GN, Lowder CY, Deegan WF, Raizman MB, Meisler DM. Anterior Segment and External Ocular Disorders Associated with Human Immunodeficiency Virus Disease. Surv Ophthalmol 2007; 52:329-68. [PMID: 17574062 DOI: 10.1016/j.survophthal.2007.04.010] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The eye is a common site for complications of human immunodeficiency virus (HIV) infection. Although cytomegalovirus retinitis remains the most prevalent of the blinding ocular disorders that can occur in individuals with the acquired immunodeficiency syndrome (AIDS), several important HIV-associated disorders may involve the anterior segment, ocular surface, and adnexae. Some of these entities, such as Kaposi sarcoma, were well described, but uncommon, before the HIV epidemic. Others, like microsporidial keratoconjunctivitis, have presentations that differ between affected individuals with HIV disease and those from the general population who are immunocompetent. The treatment of many of these diseases is challenging because of host immunodeficiency. Survival after the diagnosis of AIDS has increased among individuals with HIV disease because of more effective antiretroviral therapies and improved prophylaxis against, and treatment of, opportunistic infections. This longer survival may lead to an increased prevalence of anterior segment and external ocular disorders. In addition, the evaluation and management of disorders such as blepharitis and dry eye, which were previously overshadowed by more severe, blinding disorders, may demand increased attention, as the general health of this population improves. Not all individuals infected with HIV receive potent antiretroviral therapy, however, because of socioeconomic or other factors, and others will be intolerant of these drugs or experience drug failure. Ophthalmologists must, therefore, still be aware of the ocular findings that develop in the setting of severe immunosuppression. This article reviews the spectrum of HIV-associated anterior segment and external ocular disorders, with recommendations for their evaluation and management.
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Affiliation(s)
- Bennie H Jeng
- The Cole Eye Institute, Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA.
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Rauz S, Tuft S, Dart JKG, Bonshek R, Luthert P, Curry A. Ultrastructural examination of two cases of stromal microsporidial keratitis. J Med Microbiol 2004; 53:775-781. [PMID: 15272065 DOI: 10.1099/jmm.0.45524-0] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Two cases with chronic stromal keratitis are described in immunocompetent hosts where the diagnosis was originally thought to be herpetic or adenoviral disease. Light microscopy and ultrastructural examination of corneal tissue by electron microscopy were performed following penetrating keratoplasty (case 1) and corneal biopsy (case 2). Specimens from both cases were analysed for viral identification by PCR. Two different species of Microsporidia were identified. Case 1 represents the fourth reported case of corneal stromal Vittaforma corneae where the spores measured 3.3 x 1.4 microm, arranged in characteristic linear groups of about four to eight. Each spore contained a diplokaryotic nucleus and a single row of ten polar tube coils. By contrast, case 2 is the first reported case of stromal keratitis caused by Trachipleistophora hominis. In this case, spores measured 4 x 2.4 microm, located typically within packets. In this species, the polar tube was arranged as a single row of about 10-13 profiles. Viral DNA could not be amplified by PCR. In conclusion, microsporidial stromal keratitis should be considered in culture-negative cases refractory to medical therapy. As microbiological culture techniques are unsuccessful, diagnosis may only be established following histopathological and ultrastructural examination of corneal tissue.
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Affiliation(s)
- Saaeha Rauz
- Corneal and External Diseases Service, Moorfields Eye Hospital NHS Trust, City Road, London EC1V 2PD, UK 2,3Department of Histopathology2 and Health Protection Agency3, Manchester Royal Infirmary, Oxford Road, Manchester M13 9WZ, UK
| | - Stephen Tuft
- Corneal and External Diseases Service, Moorfields Eye Hospital NHS Trust, City Road, London EC1V 2PD, UK 2,3Department of Histopathology2 and Health Protection Agency3, Manchester Royal Infirmary, Oxford Road, Manchester M13 9WZ, UK
| | - John K G Dart
- Corneal and External Diseases Service, Moorfields Eye Hospital NHS Trust, City Road, London EC1V 2PD, UK 2,3Department of Histopathology2 and Health Protection Agency3, Manchester Royal Infirmary, Oxford Road, Manchester M13 9WZ, UK
| | - Richard Bonshek
- Corneal and External Diseases Service, Moorfields Eye Hospital NHS Trust, City Road, London EC1V 2PD, UK 2,3Department of Histopathology2 and Health Protection Agency3, Manchester Royal Infirmary, Oxford Road, Manchester M13 9WZ, UK
| | - Philip Luthert
- Corneal and External Diseases Service, Moorfields Eye Hospital NHS Trust, City Road, London EC1V 2PD, UK 2,3Department of Histopathology2 and Health Protection Agency3, Manchester Royal Infirmary, Oxford Road, Manchester M13 9WZ, UK
| | - Alan Curry
- Corneal and External Diseases Service, Moorfields Eye Hospital NHS Trust, City Road, London EC1V 2PD, UK 2,3Department of Histopathology2 and Health Protection Agency3, Manchester Royal Infirmary, Oxford Road, Manchester M13 9WZ, UK
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Lewis NL, Francis IC, Hawkins GS, Coroneo MT. Bilateral microsporidial keratoconjunctivitis in an immunocompetent non-contact lens wearer. Cornea 2003; 22:374-6. [PMID: 12792484 DOI: 10.1097/00003226-200305000-00018] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE To describe an immunocompetent male with bilateral microsporidial keratoconjunctivitis who responded to treatment with albendazole, propamidine, and fumagillin. METHODS Corneal and conjunctival epithelial scrapings from a man with bilateral keratoconjunctivitis previously treated with topical corticosteroids were evaluated by Gram stain and by fluorescence microscopy. RESULTS Gram stain and fluorescence microscopy of corneal epithelial scraping revealed organisms characteristic of microsporidia. Results of human immunodeficiency virus antibody testing were reported as nonreactive. Symptoms of ocular discomfort and clinical signs of keratoconjunctivitis resolved after five weeks of treatment that included systemic albendazole and topical propamidine isethionate 0.1% and fumagillin bicyclohexylammonium salt. A follow-up conjunctival scraping failed to detect any residual organisms 2 weeks after cessation of all treatment. CONCLUSION Microsporidial ocular infection occurred in an immunocompetent non-contact lens wearer. Microsporidial keratoconjunctivitis should be considered in any individual with atypical multifocal diffuse epithelial keratitis, regardless of immune status or recent history of contact lens wear.
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Affiliation(s)
- Noni L Lewis
- Department of Opthalmology, The Prince of Wales Hospital, University of New South Wales, Randwick, Sydney.
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Abstract
Microsporidia is a common term that has been used to refer to a group of eukaryotic, obligate intracellular protozoan parasites belonging to the phylum Microspora. They are important agricultural parasites, contaminating commercial insects; they are also important by infecting laboratory rodents, rabbits and primates. Ever since the early cases found by Magarino Torres, who reported the presence of Encephalitozoon in a patient suffering of a meningoencephalomyelitis, some human pathology caused by microsporidia has been described. However, only after the acquired immunodeficiency syndrome outbreak have these organisms appeared as significant etiological agents in different pathologies. Even so, they remain underestimated. In the present article, the importance of microsporidia for the human pathology in immunocompromised host has been stressed.
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Affiliation(s)
- J Schottelius
- Section of Parasitology, Bernhard-Nocht-Institute for Tropical Medicine, D-20359 Hamburg, Germany
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Font RL, Samaha AN, Keener MJ, Chevez-Barrios P, Goosey JD. Corneal microsporidiosis. Report of case, including electron microscopic observations. Ophthalmology 2000; 107:1769-75. [PMID: 10964843 DOI: 10.1016/s0161-6420(00)00285-2] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
OBJECTIVE To report a case of corneal stromal infection caused by a protozoon of the genus MICROSPORIDIA:, including clinical, histopathologic, and electron microscopic observations. DESIGN Case report. METHODS Light and electron microscopy studies were performed on keratectomy specimens from a 67-year-old immunocompetent man who had a unilateral chronic stromal keratitis that was refractory to medical treatment. Initial corneal biopsy followed by lamellar and penetrating keratoplasty were performed on the patient. All the specimens were studied histopathologically. RESULTS Light microscopy of the corneal biopsy and the subsequent keratectomy specimens demonstrated myriad small, round to oval microsporidial organisms measuring 3.5 to 5.0 micrometer in length that stained positively with the periodic acid-Schiff, Grocott-methenamine silver, and acid-fast methods and were gram positive. Electron microscopic observations demonstrated viable blastospores that had a thin osmiophilic outer cell wall and contained 11 to 13 coils of the filament. The light and electron microscopic features, the tinctorial characteristics, and the selective corneal stromal involvement are consistent with microsporidial keratitis. CONCLUSIONS Microsporidiosis should be considered in the differential diagnosis of a culture-negative stromal keratitis refractory to medical treatment. The diagnosis can be easily established based on the morphologic features of the protozoa in the keratectomy specimens. No effective medical treatment for the stromal disease is available. Full-thickness keratoplasty is suggested because, in our patient, lamellar keratoplasty did not preclude recurrence of the disease.
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Affiliation(s)
- R L Font
- Department of Ophthalmology, Cullen Eye Institute, Baylor College of Medicine, Houston, Texas, USA.
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Franzen C, Müller A. Molecular techniques for detection, species differentiation, and phylogenetic analysis of microsporidia. Clin Microbiol Rev 1999; 12:243-85. [PMID: 10194459 PMCID: PMC88917 DOI: 10.1128/cmr.12.2.243] [Citation(s) in RCA: 184] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Microsporidia are obligate intracellular protozoan parasites that infect a broad range of vertebrates and invertebrates. These parasites are now recognized as one of the most common pathogens in human immunodeficiency virus-infected patients. For most patients with infectious diseases, microbiological isolation and identification techniques offer the most rapid and specific determination of the etiologic agent. This is not a suitable procedure for microsporidia, which are obligate intracellular parasites requiring cell culture systems for growth. Therefore, the diagnosis of microsporidiosis currently depends on morphological demonstration of the organisms themselves. Although the diagnosis of microsporidiosis and identification of microsporidia by light microscopy have greatly improved during the last few years, species differentiation by these techniques is usually impossible and transmission electron microscopy may be necessary. Immunfluorescent-staining techniques have been developed for species differentiation of microsporidia, but the antibodies used in these procedures are available only at research laboratories at present. During the last 10 years, the detection of infectious disease agents has begun to include the use of nucleic acid-based technologies. Diagnosis of infection caused by parasitic organisms is the last field of clinical microbiology to incorporate these techniques and molecular techniques (e.g., PCR and hybridization assays) have recently been developed for the detection, species differentiation, and phylogenetic analysis of microsporidia. In this paper we review human microsporidial infections and describe and discuss these newly developed molecular techniques.
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Affiliation(s)
- C Franzen
- Department of Internal Medicine I, University of Cologne, 50924 Cologne,
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Garvey MJ, Ambrose PG, Ulmer JL. Topical fumagillin in the treatment of microsporidial keratoconjunctivitis in AIDS. Ann Pharmacother 1995; 29:872-4. [PMID: 8547736 DOI: 10.1177/106002809502900909] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
OBJECTIVE To report microsporidial keratoconjunctivitis in a patient infected with HIV who was treated with topical fumagillin. CASE SUMMARY A 37-year-old white man who was experiencing redness, pain, irritation, decreased vision, and a foreign body sensation occurring in both eyes was referred to the ophthalmology clinic. The patient had a medical history significant for AIDS, Pneumocystis carinii pneumonia, and Cytomegalovirus retinitis. Conjunctival smears were taken and stained positive for the presence of Microsporidia. The patient was diagnosed with bilateral microsporidial keratoconjunctivitis and fumagillin therapy was initiated. After 5 days of therapy, the patient reported significant improvements characterized by a decrease in blurred vision with only slight blurring in the left eye, decrease in headache, and decreased foreign body sensation. The patient continued topical fumagillin therapy for more than 14 months, with only slight blurring in the left eye and no apparent ocular toxicity as a result of fumagillin therapy. DISCUSSION Although rare in occurrence, increasing numbers of documented microsporidial infections are being reported in the medical literature, particularly in individuals who are seropositive for HIV. Clinicians need to be cognizant of microsporidial keratoconjunctivitis as another opportunistic infection in this patient population. CONCLUSIONS Although a curative agent has yet to be discovered, fumagillin represents a safe, effective, low-cost, topical agent for the treatment of microsporidial keratoconjunctivitis.
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Affiliation(s)
- M J Garvey
- University of California, Davis Medical Center, Sacramento 95817, USA
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Rickman LS, Freeman WR. Medical and virological aspects of ocular human immunodeficiency virus infection for the ophthalmologist. Semin Ophthalmol 1995; 10:91-110. [PMID: 10155633 DOI: 10.3109/08820539509059986] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- L S Rickman
- Division of Infectious Diseases, University of California San Diego School of Medicine, USA
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Affiliation(s)
- L Akduman
- Washington University, Department of Ophthalmology and Visual Sciences, St Louis, MO 63110-1093, USA
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Affiliation(s)
- B Rajeev
- Doheny Eye Institute, Los Angeles, CA
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Abstract
Microsporidia are obligate intracellular spore-forming protozoal parasites belonging to the phylum Microspora. Their host range is extensive, including most invertebrates and all classes of vertebrates. More than 100 microsporidial genera and almost 1,000 species have now been identified. Five genera (Enterocytozoon spp., Encephalitozoon spp., Septata spp., Pleistophora sp., and Nosema spp.) and unclassified microsporidia (referred to by the collective term Microsporidium) have been associated with human disease, which appears to manifest primarily in immunocompromised persons. The clinical manifestations of microsporidiosis are diverse and include intestinal, pulmonary, ocular, muscular, and renal disease. Among persons not infected with human immunodeficiency virus, ten cases of microsporidiosis have been documented. In human immunodeficiency virus-infected patients, on the other hand, over 400 cases of microsporidiosis have been identified, the majority attributed to Enterocytozoon bieneusi, an important cause of chronic diarrhea and wasting. Diagnosis of microsporidiosis currently depends on morphological demonstration of the organisms themselves. Initial detection of microsporidia by light microscopic examination of tissue sections and of more readily obtainable specimens such as stool, duodenal aspirates, urine, sputum, nasal discharge, bronchoalveolar lavage fluid, and conjunctival smears is now becoming routine practice. Definitive species identification is made by using the specific fluorescein-tagged antibody (immunofluorescence) technique or electron microscopy. Treatment options are limited, but symptomatic improvement of Enterocytozoon bieneusi infection may be achieved with the anthelmintic-antiprotozoal drug albendazole. Preliminary observations suggest that Septata intestinalis and Encephalitozoon infections may be cured with albendazole. Progress is being made with respect to in vitro propagation of microsporidia, which is crucial for developing antimicrosporidial drugs. Furthermore, molecular techniques are being developed for diagnostic purposes, taxonomic classification, and analysis of phylogenetic relationships of microsporidia.
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Affiliation(s)
- R Weber
- Department of Medicine, University Hospital, Zurich, Switzerland
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Schwartz DA, Visvesvara GS, Leitch GJ, Tashjian L, Pollack M, Holden J, Bryan RT. Pathology of symptomatic microsporidial (Encephalitozoon hellem) bronchiolitis in the acquired immunodeficiency syndrome: a new respiratory pathogen diagnosed from lung biopsy, bronchoalveolar lavage, sputum, and tissue culture. Hum Pathol 1993; 24:937-43. [PMID: 7504651 DOI: 10.1016/0046-8177(93)90106-q] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Encephalitozoon hellem is a recently described microsporidian associated with an expanding spectrum of clinical presentations in patients with the acquired immunodeficiency syndrome (AIDS). It is morphologically similar to Encephalitozoon cuniculi, a microsporidian infection of mammals and some avians, and their differentiation rests on biochemical and antigenic analyses. This report describes a patient previously diagnosed with keratoconjunctivitis due to E hellem who subsequently was found to have respiratory tract microsporidiosis by sputum cytology. He subsequently developed pulmonary symptoms and a left lower lobe interstitial infiltrate. A bronchoalveolar lavage and transbronchial biopsy revealed microsporidial bronchiolitis, and the etiologic agent was identified as E hellem using an immunofluorescent antibody technique. Lavage fluid was successfully cultured in monkey kidney cells, and cultivated E hellem organisms were studied using immunohistochemistry as well as scanning and transmission electron microscopy. The pathologic features of this newly described cause of protozoal bronchiolitis, the role of immunofluorescent antibody examination and in vitro tissue culture for species-specific diagnosis, and the significance of microsporidial pulmonary infections in AIDS patients are discussed.
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Affiliation(s)
- D A Schwartz
- Department of Pathology, Emory University School of Medicine, Atlanta, GA
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Schwartz DA, Visvesvara GS, Diesenhouse MC, Weber R, Font RL, Wilson LA, Corrent G, Serdarevic ON, Rosberger DF, Keenen PC. Pathologic features and immunofluorescent antibody demonstration of ocular microsporidiosis (Encephalitozoon hellem) in seven patients with acquired immunodeficiency syndrome. Am J Ophthalmol 1993; 115:285-92. [PMID: 8095123 DOI: 10.1016/s0002-9394(14)73577-9] [Citation(s) in RCA: 85] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
We studied the clinicopathologic features of seven patients with acquired immunodeficiency syndrome (AIDS) and ocular microsporidiosis. All patients had decreased levels of CD4-positive cells (mean, 26/ml3) and ocular symptoms; five had bilateral punctate epithelial keratopathy, one had intermittent red eyes with conjunctivitis, and one had red eyes only. Light and electron microscopy of corneal and conjunctival biopsy and cytologic specimens and intact globes disclosed microsporidia belonging to the genus Encephalitozoon. Because E. cuniculi and E. hellem, the two species of the Encephalitozoon genus, are morphologically identical, an immunofluorescent antibody technique was used for species identification. In all seven patients, the agent was identified as E. hellem. Pathologic examination of globes obtained after autopsy disclosed E. hellem infection to be restricted to the corneal and conjunctival epithelium. We studied methods for the routine diagnosis of ocular microsporidiosis in patients with AIDS, including the role of immunofluorescent antibody staining.
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Affiliation(s)
- D A Schwartz
- Department of Pathology, Emory University School of Medicine, Atlanta, Georgia
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Diesenhouse MC, Wilson LA, Corrent GF, Visvesvara GS, Grossniklaus HE, Bryan RT. Treatment of microsporidial keratoconjunctivitis with topical fumagillin. Am J Ophthalmol 1993; 115:293-8. [PMID: 8117342 DOI: 10.1016/s0002-9394(14)73578-0] [Citation(s) in RCA: 96] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Encephalitozoon hellem is a newly described cause of microsporidial keratoconjunctivitis, occurring chiefly in patients with significantly diminished CD4+ T-lymphocyte levels. This disorder is symptomatically disabling and generally recalcitrant to topical antimicrobial therapy. Two homosexual men with E. hellem keratoconjunctivitis diagnosed by Gram stain, transmission electron microscopy, and specific indirect immunofluorescent assay were treated with topical fumagillin (Fumidil B). Both patients had marked symptomatic improvement with reduction of clinical findings. Symptoms and signs recurred with temporary discontinuation of the drug. Both patients, however, remained symptom-free on maintenance levels of topical fumagillin with no evidence of toxic side effects.
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Affiliation(s)
- M C Diesenhouse
- Department of Ophthalmology, Emory University School of Medicine, Atlanta, Georgia
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McCluskey PJ, Goonan PV, Marriott DJ, Field AS. Microsporidial keratoconjunctivitis in AIDS. Eye (Lond) 1993; 7 ( Pt 1):80-3. [PMID: 8325429 DOI: 10.1038/eye.1993.17] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Microsporidia are rare human opportunistic pathogens that are now increasingly recognised in patients with AIDS, most commonly as an ocular or enteric pathogen. This paper reports a case of microsporidial keratoconjunctivitis in a patient with AIDS which responded to treatment with dibromopropamidine isethionate ointment. The clinical and laboratory features of microsporidial ocular infection are reviewed.
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Affiliation(s)
- P J McCluskey
- Department of Ophthalmology, St Vincent's Hospital, Sydney, Australia
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Dunn JP, Holland GN. HUMAN IMMUNODEFICIENCY VIRUS AND OPPORTUNISTIC OCULAR INFECTIONS. Infect Dis Clin North Am 1992. [DOI: 10.1016/s0891-5520(20)30490-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Affiliation(s)
- G N Holland
- UCLA Ocular Inflammatory Disease Center, UCLA School of Medicine
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Lacey CJ, Clarke AM, Fraser P, Metcalfe T, Bonsor G, Curry A. Chronic microsporidian infection of the nasal mucosae, sinuses and conjunctivae in HIV disease. Genitourin Med 1992; 68:179-81. [PMID: 1607196 PMCID: PMC1194852 DOI: 10.1136/sti.68.3.179] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A case of chronic infection of the nasal mucosae, sinuses and conjunctivae with a microsporidian parasite in association with HIV infection and immune deficiency is reported. This microsporidian resembles both Encephalitozoon cuniculi and the newly described Encephalitozoon hellem by electron microscopy. This occurred in an adult male resident in the UK with no history of foreign travel. Although there are previous descriptions of conjunctival infections from the USA, this is the first description of infection of the nasal epithelium. Further studies are underway to classify this protozoan.
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Affiliation(s)
- C J Lacey
- Department of Genitourinary Medicine, General Infirmary, Leeds, UK
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Hennequin C, Pialoux G, Bouree P, Dupont B. Microsporidioses et syndrome d'immunodéficience acquise (SIDA). Med Mal Infect 1992. [DOI: 10.1016/s0399-077x(05)80284-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Metcalfe TW, Doran RM, Rowlands PL, Curry A, Lacey CJ. Microsporidial keratoconjunctivitis in a patient with AIDS. Br J Ophthalmol 1992; 76:177-8. [PMID: 1540567 PMCID: PMC504202 DOI: 10.1136/bjo.76.3.177] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A male patient is described with acquired immune deficiency syndrome (AIDS) who developed chronic keratoconjunctivitis and chronic sinusitis due to infection with the microsporidian Encephalitozoon cuniculi. Diagnosis was confirmed by electron microscopic examination of conjunctival epithelial cells and nasal polypectomy specimens. Treatment with propamidine isethionate 0.1% (Brolene) eye drops six times daily led to a prompt resolution of the keratoconjunctivitis.
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Didier PJ, Didier ES, Orenstein JM, Shadduck JA. Fine structure of a new human microsporidian, Encephalitozoon hellem, in culture. THE JOURNAL OF PROTOZOOLOGY 1991; 38:502-7. [PMID: 1920150 DOI: 10.1111/j.1550-7408.1991.tb04824.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Encephalitozoon hellem is a new human microsporidian isolated from corneal biopsies and conjunctival scrapings of three AIDS patients and cultured in Madin Darby canine kidney (MDCK) cells. Encephalitozoon hellem and Encephalitozoon cuniculi display different protein profiles with sodium dodecyl sulfate-polyacrylamide gel electrophoresis and unique antibody binding patterns with murine antisera against Western blots of each organism. Developmental stages of E. hellem in culture are similar to E. cuniculi. Meronts are 1.3-2.7 microns in diameter, develop within a parasitophorous vacuole adjacent to the vacuolar membrane, divide by binary fission, and contain one or two discrete nuclei. Sporonts measure 2 x 3 microns, separate from the vacuolar membrane, and have a thickened outer membrane. Sporoblasts display a tri-layered wall and possess the earliest recognized polar filaments. Mature spores measure 1 x 1.5 microns and are more electron-dense than other stages. Each spore contains a single nucleus, a polar tubule with four to nine coils, thin electron-dense exospore and thick, electron-lucent endospore. Although E. hellem and E. cuniculi differ biochemically and immunologically, their fine structure and development are indistinguishable.
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Affiliation(s)
- P J Didier
- Department of Pathology, Tulane Regional Primate Research Center, Tulane University, Covington, Louisiana 70433
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Hollister WS, Canning EU, Willcox A. Evidence for widespread occurrence of antibodies to Encephalitozoon cuniculi (Microspora) in man provided by ELISA and other serological tests. Parasitology 1991; 102 Pt 1:33-43. [PMID: 1903878 DOI: 10.1017/s0031182000060315] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The enzyme-linked immunosorbent assay (ELISA) was used to survey human sera for antibodies to Encephalitozoon cuniculi using spores obtained from in vitro cultures as antigen. Sera were obtained from patients with tropical diseases, neurological and renal disorders, patients who were HIV positive and those who had been tested for HIV but found to be negative. Sera from inhabitants of the village of Jali, The Gambia and from healthy blood donors were also examined. Numerous sera from all groups except the blood donors gave positive ELISA reactions at dilutions of 1:400. On titration, those with titres of 1:400 were reclassified as negative. Antibody titres of 1:800 and above were considered to be indicative of past or present infections with E. cuniculi. Many of these ELISA seropositives were also positive by IFAT or PAP. When examined by Western blotting of SDS-PAGE protein profiles of E. cuniculi spores, sera from many patients who had a tropical association reacted with the characteristic profiles shown by known positive mouse and rabbit sera. Others in the tropical group showed antibody binding to some but not all of the immunodominant polypeptides and yet others were negative in spite of their reactivity in the ELISA, IFAT or PAP test. Less agreement between ELISA and Western blotting results was obtained with the other groups of patients, although reactivity with one or more of the major polypeptide bands was sometimes seen. Serum from one blood donor, examined by ELISA and Western blotting, was positive. Differences in the methods of antigen preparation and of epitopes recognized by individuals may account for different reactivities in the tests. It is concluded that infections of E. cuniculi are common in the tropics and that reactivations of these infections might be a hazard to AIDS patients.
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Yee RW, Tio FO, Martinez JA, Held KS, Shadduck JA, Didier ES. Resolution of microsporidial epithelial keratopathy in a patient with AIDS. Ophthalmology 1991; 98:196-201. [PMID: 1848925 DOI: 10.1016/s0161-6420(91)32331-5] [Citation(s) in RCA: 90] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
A patient with a positive human immunodeficiency virus (HIV) titer and cryptococcal meningitis suffered bilateral epithelial keratopathy caused by Encephalitozoon, which did not respond to sulfas, erythromycin, bacitracin, tobramycin, neomycin, polymyxin B, or fluconazole. Eventual administration of itraconazole for the meningitis apparently produced resolution of the long-lasting (2-month) ocular infection. This new oral triazole antifungal may be valuable against the increasingly prevalent microsporidial infections in patients with acquired immune deficiency syndrome. Debulking of the infection by corneal scraping may have contributed to the authors' success.
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Affiliation(s)
- R W Yee
- Department of Ophthalmology, University of Texas Health Science Center, San Antonio 78284
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