Advances in Drug Treatment of Fungal Keratitis

Fungal keratitis is an important cause of corneal blindness in China, accounting for 45% of infectious keratitis. The main pathogenic bacteria include yeast, filamentous bacteria and nearly 100 kinds of fungi, which are difficult to diagnose, difficult to treat and poor prognosis. When the infected fungal strains have strong virulence and poor drug sensitivity, it is easy to prolong the disease. Once the fungal infection involves the whole limbus and reaches the whole layer of the cornea, it will be followed by intraocular tissue infection such as anterior chamber, lens and vitreous body. When the infection is difficult to control and the visual function is seriously damaged, the enucleation of eye contents has to be performed, which causes irreversible harm to the patient’s appearance and physical and mental health. Therefore, in order to gain greater hope for the vision of patients with fungal keratitis, In recent years, with the continuous progress of clinical medicine and microbiological diagnostics, the treatment methods of fungal keratitis have been constantly updated. This article will briefly review the new progress in drug and surgical treatment of fungal keratitis in recent years to provide patients with better visual prognosis. .

Antifungal efficacy of natamycin in experimental fusarium solani keratitis

AIM: To evaluate the efficacy of topical administration Natamycin, which is produced by China, in an experimental rabbit model of Fusarium solani keratitis, to provide experimental basis for the application of clinical safety. METHODS: Fusarium solani was induced in the right eye of 30 New Zealand rabbits. Forty-eight hours after inoculation, the animals were divided into 3 different treatment groups, 10 rabbit eyes of each group: Group 1 (Natamycin) treated with topical Natamycin, group 2 (Natacyn) treated with topical Natacyn, group 3 (control) treated with topical saline solution. The eyes of each group was examined clinically with slit lamp using ulcer scoring system on day 4, 10, 15, and 21 for status of healing, corneal vascularisation, iritis, hypopyon and macular nebula. The findings were recorded on day 10 and day 21. RESULTS: Ulcer score on day 10, day 15, day 21: The score of Natamycin group are 1.45 +/- 0.16, 1.08 +/- 0.11, 0.70 +/- 0.40. The score of Natacyn group are 1.35 +/- 0.12, 1.10 +/- 0.12, 0.65 +/- 0.35. the score of control group are 1.30 +/- 0.08, 3.63 +/- 0.28, 3.80 +/- 0.16. Natamycin group and Natacyn group were different from control group (P <0.01). There is no difference between Natamycin group and Natacyn group. Status of healing on day 10 and day 21: The cure rate of the Natamycin group is 90% on day 10, and 100% on day 21. The cure rate of the Natacyn group is 80% on day 10, and 100% on day 21.Natamycin group and Natacyn group were different from control group (P<0.01). There is no difference between Natamycin group and Natacyn group. Corneal vascularisation, iritis, hypopyon and macular nebula on day 10 and day 21: in Natamycin group, the number of the eyes which have Corner vascularisation, iritis, hypopyon and macular nebula are 2,0,0,2. In Natacyn group, the number of the eyes which have Corner vascularisation, iritis, hypopyon and macular nebula are 1,0,0,2. In control group, the number of the eyes which have Corner vascularisation, iritis, hypopyon and macular nebula are 9,9,8,9.Natamycin group and Natacyn group were different from control group (P<0.01). There is no difference between Natamycin group and Natacyn group. CONCLUSION: Natamycin was found to be effective in fungal keratitis, similar to Natacyn, and it can stop the corner vascularisation, iritis, hypopyon and macular nebula to happen. Natamyin manufactured in China is effective against fungal keratitis, with esay availability and low toxicity in its use.

Conjunctival microbiome changes associated with fungal keratitis: metagenomic analysis

AIM: To investigate the ocular surface microbiome profile of patients with fungal keratitis(FK) through bacterial 16 S r DNA sequencing. METHODS: The swab samples were collected from 8 patients with FK(Group 1 from the corneal ulcer, Group 2 from the conjunctival sac of the infected eyes, and Group 3 from the conjunctival sac of the fellow eyes) and 10 healthy eyes(Group 4 from the conjunctival sac). Bacterial 16 S rDNA V4-V5 region sequencing was performed to characterize the bacterial communities on the ocular surfaces of the patients with FK. RESULTS: Our metagenomic data showed that 97% of the sequence reads were categorized into 245 distinct bacterial genera, with 67.75±7.79 genera detected in Group 1, 73.80±13.44 in Group 2, 74.57±14.14 in Group 3, and 89.60±27.49 in Group 4. Compared with the healthy eyes(Group 4), both infected(Groups 1 and 2) and fellow eyes(Group 3) of the patients with FK showed reduced bacterial diversity and altered ocular surface microbiota compositions, with lower abundance of Corynebacterium and Staphylo coccus and higher abundances of Pseudomonas, Achromobacter, Caulobacter and Psychrobacter. CONCLUSION: Our report depicts the altered ocular surface bacterial community structures both in the affected and fellow eyes of patients with FK. These changes may contribute to the pathogenesis of FK or the increased risk for FK.

Review of clinical and basic approaches of fungal keratitis

Fungal keratitis（FK） is a serious disease which can cause blindness. This review has current information about the pathogenesis, limitations of traditional diagnosis and therapeutic strategies, immune recognition and the diagnosis and therapy of FK. The information of this summary was reviewed regularly and updated as what we need in the diagnosis and therapy of FK nowadays.

Effects of COX-2 inhibitor NS-398 on IL-10 expression in rat fungal keratitis

AIM: To investigate the expression of interleukin-10 (IL-10) and the effect of NS-398 (COX-2 inhibitor) on the expression of IL-10 in fungal keratitis in rats, and analyze its effects on anti-fungus immunity. METHODS: Ninety Wister rats were randomly divided into 3 groups. Group A was blank control group (10 eyes). Group B was fungal keratitis group (40 eyes). Group C was fungal keratitis group treated with NS-398 (40 eyes). PAS staining, 100g/L potassium hydroxide (KOH) smear and fungal culture confirmed the successful establishment of fungal keratitis model. After the central epithelium was scraped, Fusarium solani colonies were applied and contact lens was put on the right cornea of group B and C, and plane contact lens was put on the left cornea of control eyes. Phosphate buffered saline (PBS) eyedrops were given for group B and NS-398 eyedrops for group C. The expression of IL-10 on corneas of group B and C on the 1(st) day, 3(rd) days, 75(th) days, and 14(th) days were detected by immunohistochemistry and semi- quantitative reverse transcription- polymerase chain reaction (RT-PCR). RESULTS: Histopathologic examination showed neutrophil infiltration and severe tissue necrosis in ulcer cornea. PAS staining confirmed the existence of hyphae and spores in the superficial layer of stroma. In the blank and control groups almost no expression of IL-10 was detected at any observing points. In group B the expression of IL-10 increased at first and decreased thereafter. Its expression also showed significant difference at any observing points (P < 0.01). Compared with group B, the expression of IL-10 in group C showed no difference on the 1(st)day, decrease on the 3(rd) day, but a significant increase on the 7(th) day and 14(th) day. CONCLUSION: IL-10 takes part in the occurrence and development of fungal keratitis. NS-398 can upgrade the expression of IL-10 in fungal keratitis in the later period of the ulcer. Meanwhile, pathologic observation showed a slightly corneal opacity. IL-10 may play an important role in the process of cornea anti-damage repair.

Amniotic membrane covering promotes healing of cornea epithelium and improves visual acuity after debridement for fungal keratitis

AIM:To investigate the effect of amniotic membrane covering(AMC) on the healing of cornea epithelium and visual acuity for fungal keratitis after debridement.METHODS:Twenty fungal keratitis patients were divided into two groups randomly, the AMC group and the control group, ten patients each group. Both debridement of the infected cornea tissue and standard anti-fungus drugs treatments were given to every patients, monolayer amniotic membrane were sutured to the surface of the entire cornea and bulbar conjunctiva with 10-0 nylon suture for patients in the AMC group.The diameter of the ulcer was determined with slit lamp microscope and the depth of the infiltration was determined with anterior segment optical coherence tomography. Uncorrected visual acuity(UCVA) was tested before surgery and three month after healing of the epithelial layer. The healing time of the cornea epithelium, visual acuity(VA) was compared between the two groups using t- test.RESULTS:There was no statistical difference of the diameter of the ulcer, depth of the infiltration, height of the hypopyon and VA between the two groups beforesurgery(P 】0.05). The average healing time of the AMC group was 6.89 ±2.98 d, which was statistically shorter than that of the control group(10.23±2.78d)(P 【0.05).The average UCVA of the AMC group was 0.138 ±0.083,which was statistically better than that of the control group(0.053±0.068)(P 【0.05).CONCLUSION:AMC surgery could promote healing of cornea epithelium after debridement for fungal keratitis and lead to better VA outcome.

Clinical observation of removal of the necrotic corneal tissue combined with conjunctival flap covering surgery under the guidance of the AS-OCT in treatment of fungal keratitis

AIM: To study the clinical observation of removal of the necrotic corneal tissue combined with conjunctival flap covering surgery under the guidance of the AS-OCT in treatment of fungal keratitis. METHODS:A retrospective study was done to 10 patients (10 eyes) who had accepted removal of the necrotic corneal tissue combined with conjunctival flap covering surgery for fungal keratitis,the diagnosis by corneal scraping and smear examination or confocal microscopy check hyphae. Local and systemic antifungal therapy more than one week for all patients, corneal ulcer enlarge or no shrink. Slit lamp microscope examination the diameter of corneal ulcer about 2mm-4mm. Anterior segment optical coherence tomography (AS-OCT)examine the depth of corneal ulcer between 1/3-1/2, infiltrate corneal stroma about 20um-80um,the diameter of corneal ulcer about 3mm-6mm.Type-B ultrasonic exclusion endophthalmitis. Complete removal lesions until transparent of stoma, make conjunctival flap equal or greater than ulcer 1mm nearby conjunctiva. Continued antifungal therapy. The vision, fungal recurrence, conjunctival flap rollback or desquamate were analysed. ' RESULTS:Ten patients had success done this surgery, the corneal ulcer was not enlarge and healing afteroperation. 7 cases were bridging conjunctival flap and 3cases were single conjunctival flap. Preoperation vision above 0.1 had 8 cases,7 cases had vision above 0.1 one week after surgery, while 1 cases vision droped from 0.3 to 0.05.There was not recurrent for fungal,2 cases conjunctival flap rollback:1 case was bridging and 1case was single flap, no conjunctival flap desquamate. CONCLUSION: It is safe and effective to perform removal of the necrotic corneal tissue combined with conjunctival flap covering surgery under the guidance of the AS-OCT in treatment of fungal keratitis which werenot sensitive or aggravate for antifungal drugs.

Corneal collagen cross-linking and liposomal amphotericin B combination therapy for fungal keratitis in rabbits

AIM： To observe the therapeutic effect of corneal collagen cross-linking（CXL） in combination with liposomal amphotericin B in fungal corneal ulcers.METHODS： New Zealand rabbits were induced fungal corneal ulcers by scratching and randomly divided into 3groups, i.e. control, treated with CXL, and combined therapy of CXL with 0.25% liposomal amphotericin B（n =5 each）. The corneal lesions were documented with slit-lamp and confocal microscopy on 3, 7, 14, 21 and 28 d after treatment. The corneas were examined with transmission electron microscopy（TEM） at 4wk.RESULTS： A rabbit corneal ulcer model of Fusarium was successfully established. The corneal epithelium defect areas in the two treatment groups were smaller than that in the control group on 3, 7, 14 and 21d（P 〈0.05）. The corneal epithelium defect areas of the combined group was smaller than that of the CXL group（P 〈0.05） on 7 and 14 d, but there were no statistical differences on 3, 21 and 28 d. The corneal epithelium defects of the two treatment groups have been healed by day 21. The corneal epithelium defects of the control group were healed on 28 d. The diameters of the corneal collagen fiber bundles（42.960 ±7.383 nm in the CXL group and 37.040±4.160 nm in the combined group） were thicker than that of the control group（24.900±1.868 nm）,but there was no difference between the two treatment groups. Some corneal collagen fiber bundles were distorted and with irregular arrangement, a large number of fibroblasts could be seen among them but no inflammatory cells in both treatment groups. CONCLUSION： CXL combined with liposomal amphotericin B have beneficial effects on fungal corneal ulcers. The combined therapy could alleviate corneal inflammattions, accelerate corneal repair, and shorten the course of disease.

Changes in corneal innervation and pain responses in fungal keratitis

AIM: To characterize changes in the cornea nerve and pain responses in fungal keratitis(FK).METHODS: A retrospective analysis of in vivo confocal microscopy images of 11 FK corneas was performed, and the results were compared with those for 11 normal corneas. Subbasal corneal nerves were analyzed for total nerve number, main nerve trunk number, branching patterns and tortuosity. C57 BL/6 mice were infected with Aspergillus fumigatus. Disease severity was determined through clinical scoring and slit lamp photography. Corneas were harvested at 1, 3, 5, and 7 d post infection(p.i.) and assessed for β III tubulin. Corneal mechanical sensitivity thresholds were detected by von Frey test. β-endorphin(β-EP) and μ receptor protein expression was detected through Western blotting.RESULTS: Total nerve number, main nerve trunk number, and nerve branching were significantly lower in FK patients than in controls, but tortuosity was not significantly different. In infected mice, subbasal nerve density decreased from 1 d p.i., reaching a minimum at 5 d p.i. Clinical scores rose at 1 d p.i., peaked at 3 d p.i., and decreased at 5 d p.i. Mechanical sensitivity thresholds showed the same trends. β-EP and μ receptor protein expression increased after infection.CONCLUSION: Corneal nerve density is lower in FK patients and Aspergillus fumigatus-infected mice than in controls. Pain sensitivity decreases with postinfection corneal ulcer aggravation. β-EP and μ receptor proteins are both upregulated in infected mouse corneas.

Rapamycin liposome gutta inhibiting fungal keratitis of rats

AIM: To study the therapeutic effect of rapamycin liposome eyedrops on fungal keratitis(FK) and its effect on the expression of monocyte chemotactic protein-1(MCP-1).METHODS: This study adopted the thin film dispersion method to prepare rapamycin liposomes eyedrops, as well as used the orthogonal design to analyze and study main influencing factors that affected the quality of liposomes. Totally 96 healthy Wistar rats were randomly divided into four groups: normal control group(A), FK blank control group(B), FK blank liposomes control group(C), and 30 FK rapamycin liposome treatment group(D). Groups B, C, and D were first prepared as FK animal models. The corneal response was recorded in details on day 1, 3, 5, 7, and 14 after modeling. Six rats were obtained and immunohistochemistry and semi-quantitative reverse transcription polymerase chain reaction(RT-PCR) were used to detect the expression of MCP-1 protein and mRNA, respectively.RESULTS: The severity of corneal lesions in the rapamycin treatment group was reduced, and the clinical score of the slit lamp examination was lower than that of Groups B and C(P<0.01). The expression of MCP-1 in rapamycin treatment group was significantly inhibited, comparing to that of groups B and C(P<0.01).CONCLUSION: Liposome is a good drug carrier for rapamycin. Rapamycin has a good therapeutic effect on FK. It can reduce FK fungal burden and significantly inhibit the expression of MCP-1 protein and mRNA.

Anti-inflammatory effects of astaxanthin against fungal keratitis

AIM:To characterize effect of astaxanthin(ASX)in Aspergillus fumigatus(A.fumigatus)induced keratitis in mouse model.METHODS:In vivo,fungal keratitis mouse model was established in C57BL/6 mice using A.fumigatus,followed by ASX or dimethyl sulfoxide(DMSO)treatment.Clinical responses were evaluated by clinical score and myeloperoxidase(MPO)assay.Inflammatory cytokines were assessed by reverse-transcription polymerase chain reaction(RT-PCR),Western blot,immunofluorescence,and enzyme-linked immuno sorbent assay(ELISA).RESULTS:In animal model,ASX improved corneal transparency and clinical response,suppressed the expression of inflammatory cytokine like IL-1β,TNF-α,and HMGB-1.Neutrophil levels have been shown to decrease in ASX-treated cornea by immunofluorescence and MPO.TLR2 and TLR4 levels were lower in ASX-treated group than DMSO-treated.CONCLUSION:ASX can suppress inflammatory response and reduce inflammatory cytokine production in mice model with A.fumigatus keratitis.

Potential role of nuclear receptor ligand all-trans retinoic acids in the treatment of fungal keratitis

·Fungal keratitis(FK) is a worldwide visual impairment disease. This infectious fungus initiates the primary innate immune response and, later the adaptive immune response. The inflammatory process is related to a variety of immune cells, including macrophages, helper T cells, neutrophils, dendritic cells, and Treg cells, and is associated with proinflammatory, chemotactic and regulatory cytokines. All-trans retinoic acids(ATRA)have diverse immunomodulatory actions in a number of inflammatory and autoimmune conditions. These retinoids regulate the transcriptional levels of target genes through the activation of nuclear receptors.Retinoic acid receptor α(RAR α), retinoic acid receptor γ(RAR γ), and retinoid X receptor α(RXR α) are expressed in the cornea and immune cells. This paper summarizes new findings regarding ATRA in immune and inflammatory diseases and analyzes the perspective application of ATRA in FK.

Combined Application of 5% Natamycin and 0.2% Fluconazole for the Treatment of Fungal Keratitis

Purpose: To observe the clinical efficacy of combined use of 5% natamycin and 0.2% fluconazole for the treatment of fungal keratitis. Methods:A total of 65 cases diagnosed with fungal keratitis by direct smear and/or fungus culture from January 2010 to January 2013 were enrolled in this study.The duration from the onset of symptoms to admission to our ophthalmic center ranged from 9 to 90 d (mean 29.5 ±19.1 d) in the severe group, which significantly differed from the 7 to 36 d (mean 16.6±7.1 d) in the non-severe group (P<0.01). All cases were divided into non-severe and severe groups based on the degree of corneal inflammation. All cases were treated with topical use of 5% natamycin and 0.2% fluconazole once per hour. The same clinical and examination protocols were adopted for both groups. Results:In the non-severe group,23 of the 24 patients (95.8%) were healed, and 1 (4.2%) showed treatment effica cy. In the severe group,12 of 41 patients (29.3%) were healed, 11(26.8%) showed clinical efficacy, and 18(43.9%) showed no efficacy. The patients between two groups significantly differed in terms of efficacy (P<0.01). Conclusion:Combined use of 5% natamycin and 0.2% fluconazole is efficacious in treating fungal keratitis, especially mild or moderate infections.

Mincle in the innate immune response of mice fungal keratitis

AIM： To investigate how macrophage inducible C-type lectin（Mincle） influences inflammation in mice fungal keratitis induced by Aspergillus fumigatus（A. fumigatus）.METHODS： C57 BL/6 mice were infected with A. fumigatus after pretreated with Mincle agonist TDB or Mincle neutralizing antibody（MincleAb）, taking DMSO or IgG as control group respectively. The cornea lesions were monitored with slit-lamp microscope and evaluated by clinical score. Mincle expression was assessed using reverse transcriptionploymerase chain reaction（RT-PCR） and immunostaining. The expression of cytokines（IL-1β, TNF-α and IL-6） chemokines（CXCL-1 and MIP-2） was determined by RTPCR and ELISA. Neutrophil infiltration was observed by immunostaining. The levels of nitric oxide（NO） generated by corneas were tested by Griess reaction. RESULTS： Mincle mRNA and protein levels were higher in infected corneas than normal corneas of C57 BL/6 mice, saving clinical scores revealed differences. When pretreated with Mincle agonist TDB, the mRNA and protein levels of IL-1β, TNF-α and IL-6 in infected corneas were significantly increased compared with the control group（P〈0.01）. Results of the counterpart in corneas pretreated with Mincle neutralizing antibody was decreased consistently（P〈0.01）. Expression of CXCL1 and MIP-2 mRNA levels were upregulated in TDB group and down-regulated in Mincle Ab group（P〈0.01）, coincide with neutrophil aggregation degree in corneas showed by immunostaining. As for the concentration of NO, it was promoted in TDB group compared with DMSO control group, and decreased in Mincle Ab group compared with Ig G control group.CONCLUSION： Mincle plays a dual role in mice fungal keratitis. It participates in the innate immune system by enhancing inflammation. What＇s more, Mincle can mediate cytotoxic effects by regulating the formation of NO.

Immunologic mechanism of fungal keratitis

Fungal keratitis(FK)is a refractory disease that poses a serious threat to vision,with common risk factors like eye trauma,contact lens wearing,topical corticosteroids and antibiotic abuse.Nowadays,topical and systemic anti-fungal drugs and ocular surgeries are still the main therapeutic modalities.However,the pathogenesis of FK,especially the immunologic mechanism within it,has not yet been deeply clarified.A better understanding of the pathogenesis of FK is imperative for more effective therapies and prognosis.Meanwhile,the immune protection strategies are also urgently required to manage FK.This review highlights recent advances in the immunologic mechanism in the pathogenesis of FK,in hope of providing valuable reference information for more effective anti-fungal treatment.

Two-step strategy—conjunctival flap covering surgery combined with secondary deep anterior lamellar keratoplasty for the treatment of high-risk fungal keratitis

AIM:To investigate whether the two-step strategy[conjunctival flap covering surgery(CFCS)combined with secondary deep anterior lamellar keratoplasty(DALK)]is effective for patients with high-risk fungal keratitis(FK).METHODS:In this noncomparative,retrospective case series,10 subjects(6 males,4 females)with a mean age of 56.5±7.1(range 47-72)y with high-risk FK undergone the two-step strategy were included.Reported outcome measures were healing of the corneal ulcer,recurrence of FK,reject reaction,improvement in best corrected visual acuity(BCVA)and relevant complications.RESULTS:The average diameter of corneal infiltrates was 7.50±0.39 mm,ranging from 6.94 to 8.13 mm.The mean depth of corneal infiltrates was 422.4±77.1μm,ranging from 350 to 535μm.The mean corneal thickness was 597.4±117.3μm,ranging from 458 to 851μm.Hypopyon and endothelial plaques were presented in all patients.The period between the two steps was 3.65±0.9(ranging from 3 to 5)mo.The graft diameter was 7.75±0.39 mm.At the last follow-up(average 9.25±3.39,ranging from 5.5 to 17mo),no fungal recurrence or graft rejection appeared,and all patients showed improvement of BCVA.One patient suffered from liver function impairment due to oral voriconazole for 4wk and recovered spontaneously after 1wk of drug withdrawal.CONCLUSION:The two-step strategy is safe and effective in the treatment of high-risk FK by transforming intentional therapeutic penetrating keratoplasty during acute infection to later optical DALK.It is a practical strategy,especially in areas lacking fresh donor corneas and eye bank services.

The pathogenic spectrum of fungal keratitis in northwestern China

I am Na An, from the Shaanxi Key Lab of Ophthalmology, Shaanxi Institute of Ophthalmology,Xi＇an City First Hospital, Xi＇an, Shaanxi Province, China. Fungal keratitis is a severe problem in most developing countries.

Spectrum of fungal keratitis: clinicopathologic study of 44 cases

AIM: To determine the causative agents of fungal keratitis and study the predisposing factors over a period of ten years in a single tertiary care hospital. ·METHODS: A retrospective analysis of fungal corneal ulcers was done from 2003-2012. Patients’ clinical data were noted from the file records. Correlation of histopathological diagnosis was done with the report on fungal culture. · RESULTS: Mycotic keratitis was established in 44 cases by a positive fungal culture. Direct microscopic examination of potassium hydroxide(KOH) mounts revealed fungal elements in 39 cases while 40 cases showed fungus on Gram stained smears. Males(54.55%) were more commonly affected than the females(45.45%). The age ranged from 18 to 82 years. Most common age group to be involved was 41-60 years. Predisposing risk factors were seen in 34(77.27%) cases. Most common findings on clinical examination were anterior chamber reaction and conjunctival injection seen in all the cases. Other common findings were stromal infiltration and hypopyon seen in 20(45.45%) and 18(40.91%) cases respectively. On histopathological examination the fungus was typed,as aspergillus in 34 cases while no definite typing was possible in 10 cases. The predominant isolate was aspergillus flavus(59.09%) followed by fusarium(15.91%). Mixed fungal and bacterial infection was seen in 3(6.82%) cases. ·CONCLUSION: Although culture is the gold standard for definitive diagnosis of fungal keratitis,direct microscopic examination of corneal scrapings or histomorphological evaluation of biopsies allow a rapidpreliminary diagnosis. Early administration of antifungal treatment helps in preventing dreadful complications.

A Case of Fungal Keratitis Secondary to Cylindrocarpon Destructans

Purpose: To report the first human case of fungal keratitis caused by Cylindrocarpon destructans and to highlight the issues with the use of topical steroids, the duration of antifungal treatment and the potential role of topical ciclosporin. Methods: A patient presented following being injured in the left eye by a fuchsia plant. Data was collected by slit lamp examination and review of the case notes and microbiology reports. Results: No organisms were cultured from a corneal scrape however cultures from a corneal biopsy identified cylindrocarpon species morphologically resembling Cylindrocarpon destructans. The patient responded well to topical amphotericin and clotrimazole and oral voriconazole but, developed a corneal perforation, which required an urgent tectonic penetrating keratoplasty (PKP). Despite being on topical dexamethasone and natamycin, the patient presented two months post-operatively with a corneal epithelial defect and a large hypopyon. Subsequently, the patient developed a deep corneal infiltrate and corneal vascularisation with a persistent epithelial defect. Conclusion: This is the first reported case of keratitis caused by Cylindrocarpon destructans. The case highlights: the contentious issues in the use of topical steroids following PKP and the duration of antifungal treatment both in primary infection and following PKP. Furthermore, the case accentuates a potential role for ciclosporin as an alternative to steroids following PKP.

Differential expression of antimicrobial peptides in human fungal keratitis

AIM:To analyze a series of antimicrobial peptides(AMPs)in corneal tissue from individuals with fungal keratitis(FK)during the active phase of the fungus infection and after healing.METHODS:Patients undergone lamellar keratoplasty for the treatment of severe FK or corneal scar had their corneal buttons sampled.Quantitative real-time polymerase chain reaction(PCR)was used to ascertain the gene expression of human beta-defensin(HBD)-1,-2,-3,-9,S100A7,8,9,and LL-37.RESULTS:All AMPs’messenger ribonucleic acid(mRNA)expression was considerably elevated in all samples(n=12).In contrast to controls,where HBD-2,-3,and S100A7 mRNAs were expressed at very low levels,it was discovered that HBD-1,-9,S100A8,S100A9,and LL-37 were constitutively expressed in all healed samples(n=4).HBD-1,-2-3,S100A7,and LL-37 mRNAs were significantly increased in all active FK samples(n=8).The levels of HBD-9,S100A8,and S100A9 mRNAs were moderately upregulated in all active FK samples.Subgroup comparison showed that HBD-2 was significantly increased in Fusarium keratitis samples(n=5),and LL-37 mRNAs were significantly enhanced in Aspergillus keratitis samples(n=3).Whereas there was not significantly increased of HBD-1,-3,-9,S100A7,8,9 mRNA in Aspergillus keratitis samples compared with Fusarium keratitis samples.CONCLUSION:AMPs expression is increased in active FK,but not all AMPs are equally expressed.HBD-2 and LL-37 expression levels are the highest,showing some specificity of AMP expression related to FK.Human AMPs,particularly HBD-2 may play a significant role in Fusarium keratitis and LL-37 might be the key player in Aspergillus keratitis.