Infectious keratitis

Current Opinion in Infectious Diseases

Volumn 20, Issue 2, 2007, Pages 129-141

  Thomas, Philip Aloysius ^a   Geraldine, Pitchairaj ^b  

^a JOSEPH EYE HOSPITAL   (India)

^b BHARATHIDASAN UNIVERSITY   (India)

Author keywords

Corneal ulceration; Keratitis aetiology; Keratitis bacterial; Keratitis fungal; Keratitis viral; Suppurative keratitis

Indexed keywords

ACICLOVIR; AMIKACIN; AMPHOTERICIN B; CEFALOTIN; CHLORAMPHENICOL; CHLORHEXIDINE; CIPROFLOXACIN; CLARITHROMYCIN; CORTICOSTEROID; COTRIMOXAZOLE; CYCLOSPORIN; FLUCONAZOLE; GANCICLOVIR; GATIFLOXACIN; GENTAMICIN; HEXAMIDINE; KETOCONAZOLE; LEVOFLOXACIN; MILTEFOSINE; MOXIFLOXACIN; OFLOXACIN; POLY(HEXAMETHYLENEBIGUANIDE); POVIDONE IODINE; PREDNISOLONE; PROPAMIDINE; STAPHYLOCOCCUS VACCINE; TOBRAMYCIN; UNINDEXED DRUG; VALACICLOVIR; VORICONAZOLE;

ACANTHAMOEBA; ADENOVIRUS; BACTERIUM; BLEPHARITIS; COMBINATION CHEMOTHERAPY; CONFOCAL MICROSCOPY; CONTACT LENS; CORNEA ULCER; DISEASE PREDISPOSITION; ENVIRONMENTAL FACTOR; EXOPHIALA; EYE INJURY; EYE SURGERY; FUSARIUM; HEALTH CARE COST; HERPES SIMPLEX KERATITIS; HUMAN; IMPRESSION CYTOLOGY; KERATITIS; KERATOMYCOSIS; MONOTHERAPY; NOCARDIA; NONHUMAN; OCCUPATIONAL HAZARD; PATHOGENESIS; PENETRATING KERATOPLASTY; PROTOZOON; PSEUDOMONAS AERUGINOSA; REVIEW; SINGLE DRUG DOSE; STREPTOCOCCUS PNEUMONIAE; UNSPECIFIED SIDE EFFECT; VERNAL CONJUNCTIVITIS; VIRUS KERATITIS;

ACANTHAMOEBA; AMEBIASIS; ANIMALS; CONTACT LENSES, EXTENDED-WEAR; EYE INFECTIONS, BACTERIAL; EYE INFECTIONS, FUNGAL; EYE INFECTIONS, VIRAL; FEMALE; HUMANS; KERATITIS; MALE;

EID: 33847360047     PISSN: 09517375     EISSN: None     Source Type: Journal    
DOI: 10.1097/QCO.0b013e328017f878     Document Type: Review

References (105)

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49. Thomas PA, Leck AK, Myatt M. Characteristic clinical features as an aid to the diagnosis of suppurative keratitis caused by filamentous fungi. Br J Ophthalmol 2005; 89:1554-1558. This describes a partial diagnostic score to help in differentiating filamentous fungal from bacterial keratitis based on criteria such as serrated margins, raised slough and dry texture.
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58. Kumar M, Mishra NK, Shukla PK. Sensitive and rapid polymerase chain reaction-based diagnosis of mycotic keratitis through single-stranded conformation polymorphism. Am J Ophthalmol 2005; 140:851-857. A modified PCR technique was found superior to microscopy and culture in diagnosis of fungal keratitis but ultimately only confirmed the clinical suspicion of fungal keratitis in four patients.
59. Gregori NZ, Schiffman JC, Miller DM, Alfonso EC. Clinical trial of povidone-iodine (betadine) versus placebo in the pretreatment of corneal ulcers. Cornea 2006; 25:558-563. Povidone-iodine pretreatment of corneal ulcers before institution of specific antimicrobial therapy was not superior to placebo in improving the outcome of infectious keratitis.
60. Vasseneix C, Gargala G, Francois A, et al. A keratitis rat model for evaluation of anti-Acanthamoeba polyphaga agents. Cornea 2006; 25:597-602. This describes the first rat model of chronic amoebic keratitis, which mimics human Acanthamoeba keratitis in many respects.
61. Awwad ST, Parmar DN, Heilman M, et al. Results of penetrating keratoplasty for visual rehabilitation after Acanthamoeba keratitis. Am J Ophthalmol 2005;1080-1084. The outcome of penetrating keratoplasty was improved (no recurrences) if there was an interval of at least 3 months between discontinuation of antiamoebic therapy and performing surgery.
62. Mauger TF, Craig E. Combined Acanthamoeba and Stenotrophomonas maltophilia keratitis treated with a conjunctival flap followed by penetrating keratoplasty. Cornea 2006; 25:631-633. Polymicrobial infection was eradicated by a combination of conjunctival flap surgery, cryotherapy and keratoplasty.
63. Ly CN, Pham JN, Badenoch PR, et al. Bacteria commonly isolated from keratitis specimens retain antibiotic susceptibility to fluoroquinolones and gentamicin plus cephalothin. Clin Exp Ophthalmol 2006; 34:44-50. This describes the continued relevance of fortified topical antibiotic therapy and of fluoroquinolone monotherapy for bacterial keratitis.
64. Mitra A, Tsesmetzoglou E, McElvanney A. Corneal deposits and topical ofloxacin: the effect of polypharmacy in the management of microbial keratitis. Eye 2006; Mar 17 [Epub ahead of print].
65. Parmar P, Salman A, Kalavathy CM, et al. Comparison of topical gatifloxacin 0.3% and ciprofloxacin 0.3% for the treatment of bacterial keratitis. Am J Ophthalmol 2006; 141:282-286. This was the first paper describing efficacy of topical gatifloxacin therapy for bacterial keratitis, particularly that due to Gram-positive cocci.
66. Meallet MA. Subpalpebral lavage antibiotic treatment for severe infectious scleritis and keratitis. Cornea 2006; 25:159-163. Describes several advantages of a subpalpebral lavage technique for continuous perfusion of the eye with antibiotics; possible emergence of drug-resistant bacterial strains is not considered.
67. McDermott AM, Rich D, Cullor J, et al. The in vitro activity of selected defensins against an isolate of Pseudomonas in the presence of human tears. Br J Ophthalmol 2006; 90:609-611. This elegant study showed that activity of defensins is affected by presence of human tears. This may have implications for other therapeutic modalities in the eye as well.
68. Sponsel W, Chen N, Dang D, et al. Topical voriconazole as a novel treatment for fungal keratitis. Antimicrob Agents Chemother 2006; 50:262-268. Topical voriconazole therapy was effective for experimental keratitis due to Paecilomyces lilacinus, which is, however, a less frequent cause of filamentous fungal keratitis than Fusarium or Aspergillus.
69. Ozbek Z, Kang S, Sivalingam J, et al. Voriconazole in the management of Alternaria keratitis. Cornea 2006; 25:242-244. This is a case report of the efficacy of voriconazole in therapy of keratitis due to Alternaria, another infrequent cause of filamentous fungal keratitis.
70. Garcia-Valenzuela E, Song CD. Intracorneal injection of amphotericin B for recurrent fungal keratitis and endophthalmitis. Arch Ophthalmol 2005; 123:1721-1723. Combined intrastromal and intravitreal amphotericin B led to eradication of recurrent fungal keratitis in one patient.
71. Yilmaz S, Maden A. Severe fungal keratitis treated with subconjunctival fluconazole. Am J Ophthalmol 2005; 140:454-458. Subconjunctival fluconazole therapy was effective in treating 12 of 13 patients with fungal keratitis. Only six of the infections were culture-proven, however; eight of the infections were presumably with Candida, which is known to be susceptible to fluconazole.
72. Dev S, Rajaraman R, Raghavan A. Severe fungal keratitis treated with subconjunctival fluconazole. Am J Ophthalmol 2006; 141:783. Subconjunctival fluconazole therapy led to eradication of infection in 54% of patients with filamentous fungal keratitis; there was insufficient mention of the severity of keratitis in the patients.
73. Sonego-Krone S, Sanchez-Di Martino D, Ayala-Lugo R, et al. Clinical results of topical fluconazole for the treatment of filamentous fungal keratitis. Graefe's Arch Clin Exp Ophthalmol 2006; 244:782-787. Topical fluconazole, alone or in combination with oral ketoconazole, was effective in culture-proven filamentous fungal keratitis; there was insufficient detail about severity of the keratitis in the responders.
74. Chen H-C, Tan H-Y, Hsiao C-H, et al. Amniotic membrane transplantation for persistent corneal ulcers and perforations in acute fungal keratitis. Cornea 2006; 25:564-572. Amniotic membrane transplantation promoted epithelialization and prevented corneal perforation provided there was continued antifungal treatment.
75. Kaye S, Choudhary A. Herpes simplex keratitis. Progress in Retinal and Eye Research 2006; 25:355-380. This is a very good review on herpes simplex viral keratitis that focuses on recent advances in management of the condition.
76. Tabbara KF. Treatment of herpetic keratitis. Ophthalmology 2005; 112:1640-1641. This is the first case series describing effective treatment and prophylaxis of herpetic keratitis by using ganciclovir gel 0.15%.
77. de Rojas Silva MV, Diez-Feijoo E, Javaloy J, Sanchez-Salorio M. Prophylactic perioperative antiviral therapy for LASIK in patients with inactive herpetic keratitis. J Refract Surg 2006; 22:404-406. Oral valacyclovir and topical acyclovir were used to prevent LASIK-induced reactivation of herpetic keratitis in a small group of patients.
78. Rao SN. Treatment of herpes simplex virus stromal keratitis unresponsive to topical prednisolone 1% with topical cyclosporine 0.05%. Am J Ophthalmol 2006; 141:771-772. Topical cyclosporine was a safe and effective treatment for a series of patients with non-necrotizing herpes stromal keratitis who had not responded to corticosteroids.
79. Bauer D, Lu M, Wasmuth S, et al. Immunomodulation by topical particle-mediated administration of cytokine plasmid DNA suppresses herpetic stromal keratitis without impairment of antiviral defense. Graefe's Arch Clin Exp Ophthalmol 2006; 244:216-225. This interesting paper highlights probable future trends in therapy of herpetic stromal keratitis by delivering cytokine DNA directly to the affected cornea.
80. Romanowski EG, Yates KA, Teuchner B, et al. N-chlorotaurine is an effective antiviral agent against adenovirus in vitro and in the Ad5/NZW rabbit ocular model. Invest Ophthalmol Vis Sci 2006; 47:2021-2026. This describes a drug with potential future use for ocular adenoviral infections.
81. Epstein PS, Pashinsky YY, Gershon D, et al. Efficacy of topical cobalt chelate CTC-96 against adenovirus in a cell culture model and against adenovirus keratoconjunctivitis in a rabbit model. BMC Ophthalmology 2006; 6:22. This describes another drug with potential future use for ocular adenoviral infections.
82. Chang JH, McCluskey PJ, Wakefield D. Toll-like receptors in ocular immunity and the immunopathogenesis of inflammatory eye disease. Br J Ophthalmol 2006; 90:103-108. This is an outstanding review of the possible role of Toll-like receptors in ocular immunity and in pathogenesis of ocular conditions, including infectious keratitis; of particular interest is the explanation for responsiveness to ocular pathogens but relative inactivity in response to the normal conjunctival bacterial flora.
83. Xue ML, Zhu H, Willcox M, et al. The role of IL-1β in the regulation of IL-8 and IL-6 in human corneal epithelial cells during Pseudomonas aeruginosa colonization. Curr Eye Res 2001; 23:406-414.
84. Oka M, Norose K, Matsushima K, et al. Overexpression of IL-8 in the cornea induces ulcer formation in the SCID mouse. Br J Ophthalmol 2006; 90:612-615. Interleukin-8 causes chemoattraction of neutrophils in corneal ulceration, which may be relevant to pathogenesis of some forms of infectious keratitis.
85. Johnson AC, Heinzel FP, Diaconu E, et al. Activation of toll-like receptor (TLR)2. TLR4 and TLR9 in the mammalian cornea induces MyD88-dependent corneal inflammation. Invest Ophthalmol Vis Sci 2005; 46:589-595.
86. Hao JL, Nagano T, Nakamura M, et al. Galardin inhibits collagen degradation by rabbit keratocytes by inhibiting the activation of pro-matrix metalloproteinases. Exp Eye Res 1999; 68:565-572.
87. Lu Y, Fukuda K, Li Q, et al. Role of nuclear factor-kB in interleukin-1-induced collagen degradation by corneal fibroblasts. Exp Eye Res 2006; 83:560-568. Nuclear factor-KB was found to mediate interleukin 1-induced collagen degradation, so could serve as a target for therapies that aim to reduce collagen destruction in infectious keratitis.
88. McClellan SA, Lighvani S, Hazlett LD. IFN-gamma: regulation of nitric oxide in the P. aeruginosa-infected cornea. Ocul Immunol Inflamm 2006; 14:21-28. Synergistic interaction between IFN-gamma and nitric oxide may explain the resistance of BALB/c mice to P. aeruginosa keratitis, with positive implications for human infectious keratitis.
89. McClellan SA, Huang X, Barrett RP, et al. Matrix metalloproteinase-9 amplifies the immune response to Pseudomonas aeruginosa corneal infection. Invest Ophthalmol Vis Sci 2006; 47:256-264. This outstanding experimental study explained the myriad mechanisms by which this metalloproteinase contributes to corneal destruction in P. aeruginosa keratitis. Metalloproteinase inhibitors may thus have a role in therapy of infectious keratitis.
90. Huang X, Du W, McClellan SA, et al. TLR4 is required for host resistance in Pseudomonas aeruginosa keratitis. Invest Ophthalmol Vis Sci 2006; 47:4910-4916. This outstanding experimental study explained the mechanisms by which defi-ciency of Toll-like receptor 4 promotes P. aeruginosa keratitis. This may have relevance for keratitis due to other ocular pathogens as well.
91. Huang X, Hazlett LD, Du W, Barrett RP. SIGIRR promotes resistance against Pseudomonas aeruginosa keratitis by down-regulating type-1 immunity and IL-1R1 and TLR4 signaling. J Immunol 2006; 177:548-556. This experimental study explained another putative mechanism (single Ig IL-1R-related molecule) by which BALB/c mice are resistant to P. aeruginosa keratitis.
92. Georgakopoulos CD, Exarchou AM, Gartaganis SP, et al. Immunization with specific polysaccharide antigen reduces alterations in corneal proteoglycans during experimental slime-producing Staphylococcus epidermidis keratitis. Curr Eye Res 2006; 31:137-146. This paper raises the possibility of preventing infectious keratitis by active and passive immunization provided the relevant microbial antigens are identified.
93. Kumar A, Zhang J, Yu FS. Innate immune response of corneal epithelial cells to Staphylococcus aureus infection: role of peptidoglycan in stimulating proinflammatory cytokine secretion. Invest Ophthalmol Vis Sci 2004; 45:3513-3522.
94. Xiao J, Nataraja K, Rajala MS, et al. Vitronectin: A possible determinant of adenovirus type 19 tropism for human corneal epithelium. Am J Ophthalmol 2005; 140:363-369. Just as this extracellular matrix protein promotes in-vitro adenoviral infection of human corneal epithelium, there may be other proteins which promote viral infection.
95. Keadle TL, Morris JL, Stuart PM. The effects of aminoguanidine on primary and recurrent ocular herpes simplex virus infection. Nitric Oxide 2005; 13:247-253. Aminoguanidine (which inhibits inducible nitric oxide synthase) was not found to affect virus shedding or clinical disease in recurrent HSV keratitis.
96. Biswas PS, Banerjee K, Kinchington PR, Rouse BT. Involvement of IL-6 in the paracrine production of VEGF in ocular HSV-1 infection. Exp Eye Res 2006; 82:46-54. Interleukin-6 produced by HSV-infected cells found to stimulate corneal and inflammatory cells to produce VEGF, a potent angiogenic factor.
97. Naito J, Mott KR, Osorio N, et al. Herpes simplex virus type 1 immediate-early protein ICP0 diffuses out of infected rabbit corneas. J Gen Virol 2005; 86:2979-2988.
98. Morishige N, Jester JV, Naito J, et al. Herpes simplex virus type 1 ICP0 localizes in the stromal layer of infected rabbit corneas and resides predominantly in the cytoplasm and/or perinuclear region of rabbit keratocytes. J Gen Virol 2006; 87:2817-2825. Eyes acutely infected with HSV were found to have this viral protein localized to corneal epithelial and stromal cells, which is a finding of great relevance to our understanding of pathogenesis of herpes stromal keratitis.
99. Serrano-Luna Jde J, Cervantes-Sandoval I, Calderon J, et al. Protease activities of Acanthamoeba polyphaga and Acanthamoeba castellanii. Can J Microbiol 2006; 52:16-23.
100. Polcicova K, Biswas PS, Banerjee K, et al. Herpes keratitis in the absence of anterograde transport of virus from sensory ganglia to the cornea. PNAS 2005; 102:11462-11467. An HSV USP mutant was constructed which did not exhibit anterograde axonal spread and yet was able to produce keratitis; this has important implications for our understanding of spread of HSV from sensory ganglia to the cornea.
101. Garate M, Marchant J, Cubillos I, et al. In vitro pathogenicity of Acanthamoeba is associated with the expression of the mannose-binding protein. Invest Ophthalmol Vis Sci 2006; 47:1056-1062. This important paper explains why Acanthamoeba cysts bind poorly to corneal cells, since there is little expression of the mannose-binding protein.
102. Garate M, Alizadeh H, Neelam S, et al. Oral immunization with Acanthamoeba mannose-binding protein ameliorates amoebic keratitis. Infect Immun 2006; Sep 18 [Epub ahead of print]. This paper raises the exciting possibility that acanthamoebic keratitis can be ameloriated, if not entirely prevented, by active immunization.
103. Getshen K, Srinivasan M, Upadhyay MP, et al. Corneal ulceration in South East Asia. I: A model for the prevention of bacterial ulcers at the village level in rural Bhutan. Br J Ophthalmol 2006; 90:276-278. This outstanding paper provides evidence that posttraumatic bacterial keratitis can be effectively prevented if antibiotic ointment is administered soon after trauma to treat the trauma-induced corneal abrasion. This is possibly the first such paper in its genre.
104. Maung N, Thant CC, Srinivasan M, et al. Corneal ulceration in South-East Asia. II: A strategy for the prevention of fungal keratitis at the village level in Burma. Br J Ophthalmol 2006; 90:968-970. This is another outstanding paper to provide evidence that posttraumatic fungal keratitis can be effectively prevented if ointment containing an antibacterial and antifungal is administered soon after trauma to treat the trauma-induced corneal abrasion.
105. Pepose JS, Keadle TL, Morrison LA. Ocular herpes simplex: changing epidemiology, emerging disease patterns and the potential of vaccine prevention and therapy. Am J Ophthalmol 2006; 141:547-557. Development of vaccines against HSV is described in this complex review; that these vaccines should not exacerbate immune-mediated herpes stromal keratitis is stressed.