Aspergillus fumigatus Hypoxia Adaptation Is Critical for the Establishment of Fungal Keratitis

Purpose

The poor visual outcomes associated with fungal keratitis (FK) underscore a need to identify fungal pathways that can serve as novel antifungal targets. In this report, we investigated whether hypoxia develops in the FK cornea and, by extension, if fungal hypoxia adaptation is essential for virulence in this setting.

Methods

C57BL/6J mice were inoculated with Aspergillus fumigatus and Fusarium solani var. petroliphilum via topical overlay or intrastromal injection. At various time points post-inoculation (p.i.), animals were injected with pimonidazole for the detection of tissue hypoxia through immunofluorescence imaging. The A. fumigatus srbA gene was deleted through Cas9-mediated homologous recombination and its virulence was assessed in the topical infection model using slit-lamp microscopy and optical coherence tomography (OCT).

Results

Topical inoculation with A. fumigatus resulted in diffuse pimonidazole staining across the epithelial and endothelial layers within 6 hours. Stromal hypoxia was evident by 48 hours p.i., which corresponded to leukocytic infiltration. Intrastromal inoculation with either A. fumigatus or F. solani similarly led to diffuse staining patterns across all corneal cell layers. The A. fumigatus srbA deletion mutant was unable to grow at oxygen levels below 3% in vitro, and corneas inoculated with the mutant failed to develop signs of corneal opacification, inflammation, or fungal burden.

Conclusions

These results suggest that fungal antigen rapidly drives the development of corneal hypoxia, thus rendering fungal SrbA or related pathways essential for the establishment of infection. Such pathways may therefore serve as targets for novel antifungal intervention.

Deoxynivalenol Damages Corneal Epithelial Cells and Exacerbates Inflammatory Response in Fungal Keratitis

BACKGROUND

Fungal keratitis (FK) is a kind of infectious keratopathy with a high rate of blindness worldwide. Deoxynivalenol (DON) has been proven to have multiple toxic effects on humans and animals.

OBJECTIVES

The aim of this study was to explore a possible pathogenic role of DON in FK.

METHODS

We first made an animal model of FK in New Zealand white rabbits, and then attempted to detect DON in a culture medium in which Fusarium solani had been grown and also in the corneal tissue of the animal model of Fusarium solani keratitis. Next, a model of DON damage in human corneal epithelial cells (HCECs) was constructed to evaluate effects of DON on the activity, migration ability, cell cycle, and apoptosis in the HCECs. Then, putative the toxic damaging effects of DON on rabbit corneal epithelial cells and the impact of the repair cycle were studied. The expression levels of inflammatory factors in the corneas of the animal model and in the model of DON-damaged HCECs were measured.

RESULTS

The Fusarium solani strain used in this study appeared to have the potential to produce DON, since DON was detected in the corneal tissue of rabbits which had been inoculated with this Fusarium solani strain. DON was found to alter the morphology of HCECs, to reduce the activity and to inhibit the proliferation and migration of HCECs. DON also induced the apoptosis and S-phase arrest of HCECs. In addition, DON was found to damage rabbit corneal epithelial cells, to prolong the corneal epithelial regeneration cycle, and to be associated with the upregulated expression of inflammatory factors in HCECs and rabbit corneas.

CONCLUSIONS

DON appears to have a toxic damaging effect on HCECs in FK, and to induce the expression of inflammatory factors, leading to the exacerbation of keratitis and the formation of new blood vessels. Future studies will explore the possibility of developing a test to detect DON in ophthalmic settings to aid the rapid diagnosis of FK, and to develop DON neutralizers and adsorbents which have the potential to improve keratocyte status, inhibit apoptosis, and alleviate inflammation, therein providing new thinking for therapy of clinical FK.

Exploring Heparanase Levels in Tears: Insights From Herpes Simplex Virus-1 Keratitis Patients and Animal Studies

Purpose

Heparanase (HPSE) cleaves heparan sulfate proteoglycans during herpes simplex virus-1 (HSV-1) infection, aiding in viral egress and disease progression. Its action has been well established in in vitro and in vivo models, but its relevance in human patients remains unclear. This study aimed to specifically evaluate tear HPSE levels of patients with herpes simplex keratitis (HSK) and to correlate these findings with a commonly used murine model.

Methods

Tear samples from patient and mice samples were collected at LV Prasad Eye Institute, Hyderabad, India, and at the University of Illinois, Chicago, IL, respectively. Tears were collected from HSV-1 patients, bacterial/fungal keratitis cases, and healthy individuals. For in vivo study, C57BL/6 mice were infected with HSV-1 (McKrae strain) followed by tear fluid collection at various time points (0-10 days).

Results

The HSV-1, bacterial keratitis, fungal keratitis, and healthy control groups each had 30 patients. There was a significant difference in HPSE expression in the HSV-1 infected eyes (1.55 ± 0.19 units/mL) compared to HSV-1 contralateral eyes (1.23 ± 0.13 units/mL; P = 0.82), bacterial keratitis eyes (0.87 ± 0.15 units/mL; P = 0.0078), fungal keratitis eyes (0.64 ± 0.09 units/mL; P < 0.00001), and normal controls (0.53 ± 0.06 units/mL; P < 0.00001). C57BL/6 mice tear HPSE expression in infected eyes was 0.66 to 5.57 ng heparan sulfate (HS) removed per minute when compared to non-infected eye (range, 0.70-3.67 ng HS removed per minute).

Conclusions

To the best of our knowledge, this study is the first to report elevated HPSE levels in the tears of patients with different forms of HSV-1 keratitis, and it confirms similar findings in a murine model, providing a valuable basis for future in vivo and clinical research on HSV-1 ocular infection.

Transcriptional profiling specifies the pathogen-specific human host response to infectious keratitis

Purpose

Corneal infections are a leading cause of visual impairment and blindness worldwide. Here we applied high-resolution transcriptomic profiling to assess the general and pathogen-specific molecular and cellular mechanisms during human corneal infection.

Methods

Clinical diagnoses of herpes simplex virus (HSV) (n=5) and bacterial/fungal (n=5) keratitis were confirmed by histology. Healthy corneas (n=7) and keratoconus (n=4) samples served as controls. Formalin-fixed, paraffin-embedded (FFPE) human corneal specimens were analyzed using the 3' RNA sequencing method Massive Analysis of cDNA Ends (MACE RNA-seq). The cellular host response was investigated using comprehensive bioinformatic deconvolution (xCell and CYBERSORTx) analyses and by integration with published single cell RNA-seq data of the human cornea.

Results

Our analysis identified 216 and 561 genes, that were specifically overexpressed in viral or bacterial/fungal keratitis, respectively, and allowed to distinguish the two etiologies. The virus-specific host response was driven by adaptive immunity and associated molecular signaling pathways, whereas the bacterial/fungal-specific host response mainly involved innate immunity signaling pathways and cell types. We identified several genes and pathways involved in the host response to infectious keratitis, including CXCL9, CXCR3, and MMP9 for viral, and S100A8/A9, MMP9, and the IL17 pathway for bacterial/fungal keratitis.

Conclusions

High-resolution molecular profiling provides new insights into the human corneal host response to viral and bacterial/fungal infection. Pathogen-specific molecular profiles may provide the foundation for novel diagnostic biomarker and therapeutic approaches that target inflammation-induced damage to corneal host cells with the goal to improve the outcome of infectious keratitis.

Ocular microbial dysbiosis and its linkage with infectious keratitis patients in Northwest China: A cross-sectional study

OBJECTIVES

To evaluate the alteration of ocular surface microbiome of patients with infectious keratitis in northwest of China.

METHODS

The corneal scrapings, eyelid margin and conjunctiva samples were collected from 57 participants, who were divided into bacterial keratitis, fungal keratitis, viral keratitis and control group. The V3-V4 region of bacterial 16S rDNA in each sample was amplified and sequenced on the Illumina HiSeq 2500 sequencing platform, and the differences among different groups were compared bioinformatically.

RESULTS

Significant alterations of the microbiome were observed in alpha-diversity and beta-diversity analysis between the keratitis groups and the control group (p < 0.05). There was no significant differences between eyelid margin and conjunctiva samples in Alpha-Diversity analysis, but a significant difference between eyelid margin and corneal scraping samples in the keratitis group (p < 0.05, independent t-test). The abundances of Bacillus, Megamonas, Acinetobacter, and Rhodococcu were significantly elevated, while the abundance of Staphylococcus was decreased in the keratitis group compared to the control group.

CONCLUSIONS

The abundance of the ocular microbiome in patients with bacterial keratitis, fungal keratitis, or viral keratitis was significantly higher than those in the control group. Keratitis patients may have ecological disorder on ocular surface microbiome compared with controls. We believe that the conjunctiva and eyelid margin microbiome combined analysis can more comprehensively reflect the composition and abundance of ocular surface microbiome.

A case of stromal microsporidiosis: medical strategies employed for successful resolution

We describe the diagnosis and successful management of a case of stromal microsporidiosis, an important emerging ocular disease. Stromal microsporidiosis is recalcitrant and very often requires therapeutic keratoplasty for effective eradication. We successfully managed a steroid-treated case diagnosed only after 9 months, with a combination of polyhexamethyl biguanide 0.04%, chlorhexidine 0.04% and fluconazole 0.3% eye drops supplemented with tablet albendazole. However, complete resolution was achieved only after epithelial debridement. Toxicity due to the drugs was not noted. Diagnostic delays, steroid use and inappropriate therapy are commonly observed in stromal microsporidiosis. In spite of these potential disadvantages, our case responded well with complete eradication of the infection. The disease being fairly indolent and slowly progressive, medical therapy should be continued, in the absence of progression or other complications. Epithelial debridement may facilitate healing.

[Clinical observation of ocular injury caused by chestnut burr]

Objective: To analyze the clinical characteristics and treatment of ocular injury caused by chestnut burr. Methods: Retrospective case series study. Data of 48 patients (48 eyes) with ocular injuries caused by chestnut burrs hospitalized in Qingdao Eye Hospital were collected from January 2013 to March 2019. All patients were followed up for at least 3 months. The time of seeking medical advice, lesion region, and characteristics and treatment methods were analyzed. Results: There were 48 patients, including 33 males and 15 females, aged 19 to 74 years [mean, (56±10) years]. The time of injury was late September (25 cases) and early October (23 cases). The shortest time to visit our hospital was 3 hours after injury, and the longest was 8 months after injury. There were 13 cases (27.1%, 13/48) with corneal and/or scleral foreign bodies. All patients were treated with corneal or scleral foreign body extraction. Twenty-four patients (50.0%, 24/48) developed fungal keratitis. Among them, 18 patients had a corneal ulcer, and the infection involved the superficial or full-thickness corneal layer. Six patients had no corneal ulcer, and the infection involved the deep stroma and corneal endothelial surface. The positive rate of fungal examination by confocal microscopy was 87.5% (21/24). Antifungal drugs (2 cases), corneal debridement (5 cases), conjunctival flap covering (2 cases), corneal stroma injection (1 case), and penetrating keratoplasty(14 cases) were given according to the depth of fungal infection. Most of the pathogens were Alternaria spp. Eleven patients (22.9%, 11/48) with necrotizing scleritis were treated with exploration of the sclera. Three patients had scleral foreign body residues on ultrasound biomicroscopy examination, which were removed by operation. Four patients were found to have fungi at the necrotic site of the sclera. Conclusions: The main types of ocular injuries caused by chestnut burrs are corneal and/or scleral foreign bodies, fungal keratitis, and necrotizing scleritis. Chestnut burr foreign bodies should be removed as soon as possible. In the case of fungal keratitis, a drug or surgical intervention should be carried out as early as possible. Necrotizing scleritis is often induced by long-term foreign body retention. Scleral incision and exploration is an effective form of treatment. (Chin J Ophthalmol, 2020, 56: 370-375).

Unorthodox ophthalmic preparations on the Ghanaian market: a potential risk for ocular and enteric infections

PURPOSE

Microbial contamination of orthodox ophthalmic preparations poses a serious threat to the user by causing ocular infections. There is no such information about unorthodox ophthalmic preparations in a medical pluralistic system such as Ghana. The aim of this study was to assess unorthodox ophthalmic medications on the Ghanaian market for possible microbial contaminations.

METHODS

Unorthodox ophthalmic preparations were collected across different herbal and homeopathic outlets in Ghana. A total of 27 samples were collected from the ten (10) regions in Ghana. The samples were inoculated in different culture media (Plate count Agar, Blood Agar, MacConkey Agar, Saboraud Dextrose Agar). The microorganisms isolated were identified using standard microbiological procedures and antimicrobial susceptibility was done to determine whether they were resistant or susceptible strains.

RESULTS

All the samples were contaminated with bacteria and the majority were contaminated with fungus. A total of forty-eight bacteria spp. was isolated thus seven different types namely: Staphylococcus aureus, Bacilli spp., Serrati spp., Escherichia coli, Pseudomonas spp., Klebsiella spp. and Shigella spp. with Staphylococcus aureus being the predominant bacteria. For fungi, a total of eleven fungi species thus four different types namely: Cephalosporium spp., Penicillium spp., Cercosporium spp. and Clasdosporium spp. with the predominant fungi being Penicillium spp. Per the class of preparations, 15 contaminants were isolated from ten (10) anti-inflammatory preparations. The fungi were all susceptible to both Ketoconazole and Fluconazole but the bacteria were resistant to all the conventional antibiotics except Ciprofloxacin and Gentamycin.

CONCLUSION

Unorthodox ophthalmic preparations found on the Ghanaian market are contaminated with bacteria and fungi of clinical importance.

Recent Clinical Manifestation and Prognosis of Fungal Endophthalmitis: A 7-Year Experience at a Tertiary Referral Center in Korea

This study analyzed the recent causes, prognosis, and treatment strategies for fungal endophthalmitis. A retrospective review of patients who were diagnosed with fungal endophthalmitis at our center was conducted. The fungal organisms isolated from each patient and the visual prognosis according to the route of infection and treatment method were analyzed. A total of 40 eyes from 30 patients with fungal endophthalmitis were included in this study. Candida species were the most common causative organisms in 35 of 40 eyes. Endogenous and exogenous endophthalmitis were observed in 33 and 7 eyes, respectively. Pre- and post-treatment best-corrected visual acuity (BCVA) was not significantly different between endogenous endophthalmitis and exogenous endophthalmitis. The 40 eyes were treated using the following modalities: intravitreal antifungal agent injection with intravenous antifungal agent (16 eyes), vitrectomy with intravenous antifungal agent (14 eyes), intravenous antifungal agent alone (9 eyes), and evisceration (1 eye). Post-treatment BCVA only significantly improved after treatment in the vitrectomy group. Candida species were the most common cause of fungal endophthalmitis, irrespective of the route of infection. The visual prognosis of fungal endophthalmitis was generally poor. In conclusion, if the general condition of the patient tolerates a surgical procedure, prompt vitrectomy and intravitreal injection of antifungal agents can improve visual acuity.

Epidemiological Aspect and common Bacterial and Fungal isolates from Suppurative Corneal Ulcer in Mymensingh Region

This prospective study was done to find out the epidemiological factors of suppurative corneal ulcer and the common causative bacterial and fungal isolates from the, patients with suppurative corneal ulcer in secondary and tertiary level hospital at Mymensingh region. A total 100 samples of corneal scrapings were collected purposively from clinically diagnosed suppurative corneal ulcer patients from March 18, 2012 to March 17, 2013. Out of the total 100 samples, bacterial species were 29(29%) cases and the fungal spacies were 71(71%) identified by the culture in blood agar, chocolate agar and sabouraud's agar media and also by microscopic examination. The bacterial species were streptococcus pneumonae 12 cases (12%), Staphylococcus aureus 9 cases (9%), pseudomonas in 6 cases (6%), and Streptococcus pyoganes 2 cases (2%). Fungal species were aspergillus fumigatus 61 cases (61%), aspergillus niger 10 cases (10%). Out of the study populations, most of the populations were from the age group of 41 to 60 years (39 %), followed 21 to 40 years (34%) age group. Considering the sex, male were 67%, female were 33%. The majority of patients came from the rural area of Mymensingh region; occupationally they were farmers (44%). Ocular trauma due to agricultural materials was the most common associated factor (71%). The etiological and epidemiological pattern of suppurative corneal ulcer varies significantly with geographical region, patient population and health of the cornea. The present study was carried out to explore the epidemiological pattern, causative bacterial and fungal specie by laboratory procedure from corneal scraping and to invent a prospective guide line for the management of corneal ulcer in the community.

[Top ten research advances of ophthalmology in China (2009-2013)]

In order to showcase the major research advances in ophthalmology of the recent five years (2009-2013) in China, the 11th Committee of the Ophthalmic Division of Chinese Medical Association launched the selection of Top Ten Research Advances of Ophthalmology in China. Each ophthalmic subspecialty group voted its top ten research advances and chose two out of ten to join the selection. The Committee voted top ten out from all candidates and announced the final result with honor. The following research advances were selected as the Top Ten Research Advances of Ophthalmology in China: Innovative theory and its application of fungal keratitis; Increased gradient pressure between IOP and ICP is the main cause of glaucomatous optic neuropathy; Domestic developed anti-VEGF medicine Conbercept has been applied successfully in the treatment of choriodal neovascularization; IL-23/IL-17 pathway and their regulation in the pathogenesis of uveitis; The creation of myopic animal model and the biochemical mechanism of myopia; Specialists' consensus on diagnosing amblyopia in children; Generation of induced pluripotent stem cells from human fibroblasts of the Tenon's capsule; The development and application of endoscopic navigation system in orbital surgery; Studies of pathogenesis on congenital cataract candidate gene mutations; The regulation for the diagnosis and treatment of pediatric retinal diseases in China and its extension.

Pediatric infectious endophthalmitis: a review

Infectious endophthalmitis is a rare but severe complication of septecemia, intraocular surgeries, or penetrating eye trauma. The etiology, prognosis, and management of pediatric endophthalmitis resulting from exogenous and endogenous infections are reviewed. Open-globe trauma and glaucoma surgery are the most frequent causes of endophthalmitis in children, whereas endogenous infection is the least common cause. Streptococcus and Staphylococcus species are common bacterial agents in both posttraumatic and postoperative pediatric endophthalmitis, whereas Candida albicans is a commonly reported organism in endogenous endophthalmitis. Additionally, Streptococcus pneumoniae and Haemophilus influenzae appear more likely as pathogens in children than in adults. The clinical manifestations and outcome usually correlate with the virulence of the infecting organism. The visual prognosis of endophthalmitis is generally poor.

Dressing Ignition and Facial Burns Following Orbital Exenteration

A 49-year-old woman with type II diabetes mellitus and a history of smoking underwent partial eyelid-sparing exenteration of the right orbit and antifungal therapy for zygomycosis. The medial orbital wall healed with a 7-mm fistula to the ethmoid sinus and a moist granulating apex required daily dressing changes for several months. Eighteen weeks following surgery, the patient cleaned her face with an alcohol wipe and then lit a cigarette, igniting the dressing covering the exenterated eye socket. This caused severe burns to the periorbital regions of both eyes requiring debridement, allografts, and then split-thickness skin grafting. Factors predisposing to this unusual and serious complication of orbital exenteration are reviewed and the subjects of treatment and prevention are discussed. To our knowledge, this is the first reported case of dressing ignition with serious facial burns in a postexenteration patient.

Endogenous endophthalmitis: microorganisms, disposition and prognosis

PURPOSE

Endogenous endophthalmitis is a severe and potentially blinding complication caused by haematogenous spreading of microorganisms. We evaluated the causative microorganisms, disposition to and prognosis of the disease.

METHODS

Thirty-one eyes of 28 patients were treated between 1996 and 2006 as the result of an endogenous endophthalmitis.

RESULTS

The microorganisms responsible for infection could be identified in 94% of all eyes investigated. Candida isolates were obtained in 15, gram-positive isolates in 11, gram-negative in one and Aspergillus in two of the 29 eyes studied. The majority of patients suffered from severe general disease (immuno-deficiency, severe surgical procedures, diabetes mellitus) and one third were intravenous drug abusers. Only one patient was otherwise healthy. The prognosis depended on the causative microorganisms. Whereas none of the eyes with Candida infection became blind, all except two of the eyes with gram-positive bacteria, Nocardia or Aspergillus infection lost visual function or had to be enucleated.

CONCLUSION

Compared to postoperative endophthalmitis, patients with endogenous endophthalmitis are more likely to have Candida isolates. Visual prognosis depends mainly on the underlying microorganisms, and is particularly poor in the case of infection with gram-positive bacteria or Aspergillus.

[Dacryocystitis caused by Candida lusitaniae]

CASE REPORT

We report the case of a 60-year-old woman with recurrent dacryocystitis of the right lacrimal sac. She did not recover after medical treatment, nor after dacryocystorhinostomy with canalicular intubation. She also had dacryocystitis on the left side. The material that was obtained during surgery was grown in a culture medium and Candida Lusitaniae was identified as the responsible organism. All symptoms disappeared after topical treatment with amphotericin B and dacryocystorhinostomy.

DISCUSSION

Dacryocystitis caused by Candida Lusitaniae is very rare. We should always consider whether Candida Lusitaniae is responsible for the primary infection or is the agent resulting from a superadded infection caused by previous antibiotic therapy.

[Comparison of minimum inhibitory concentration and postantibiotic effect of eyedrops on isolates in National Surveillance of Infectious Keratitis in Japan]

PURPOSE

To determine the minimum inhibitory concentration (MIC) and postantibiotic effect (PAE) of antibiotic eyedrops against various isolates from infectious keratitis samples.

METHOD

MIC and postantibiotic bactericidal effect (PABE)/postantibiotic fungicidal effect (PAFE) after 4 min of exposure to nine antibacterial eyedrops or four antifungals were examined using 100 clinical isolates collected by the National Surveillance of Infectious Keratitis in Japan in 2003.

RESULT

The PABEs of tobramycin and micronomicin sulfate showed better results than other drugs, and the other drugs demonstrated various PABEs depending on the bacterial strains; in particular most drugs showed low PABE against Serratia marcescens. There were no significant differences between PABEs of methicillin-resistant and methicillin-susceptible Staphylococci. Also there was no statistical correlation between MIC and PABE of Staphylococci. All the antifungals demonstrated low PAFE against Candida spp.

CONCLUSION

PABE/PAFEs vary among species of microorganisms, and since they have no relation with the usual MIC, various other factors, including species of isolates, actual clinical effects, and prevention of drug-resistance induction, should be considered in the selection of drugs.

Kératite infectieuse bilatérale chez une patiente porteuse de lentilles souples cosmétiques

We report a case of an immunocompetent 20-year-old woman, wearing planocosmetic contact lenses to change the color of her eyes, with no contact lens hygiene regimen. She developed a bilateral infectious keratitis. Acanthamoeba and Fusarium solani were isolated in both eyes. Bilateral penetrating keratoplasty was needed because of bilateral corneal perforation. Three months later, bilateral simultaneous phacoemulsification was performed because of a dense cataract and a severe decrease in her vision. Six months after surgery, her best corrected visual acuity was 0.7 in the right eye, and 0.6 in the left eye. Cosmetic contact lenses expose the wearers to the same potential ocular complications as other contact lenses. Wearers must be informed of such complications, which may be sight-threatening. Based on this case, we strongly recommend that all cosmetic contact lens wearers be examined and followed as if they were standard contact lens wearers.

[Refractory mycosis in ophthalmology]

Ophthalmological mycosis were seen as blephlitis, conjunctivitis, keratitis, orbititis, endophthalmitis. These dideases were almost hard to diagnose and were rare and refractory to treatment. Among them, keratomycosis was most frequent and relatively refractory to treatment. Orbit mycosis was rare but most refractory to treatment. Almost of them were fatal in our knowledge.

Scedosporium prolificans sclerokeratitis

BACKGROUND

The fungus Scedosporium prolificans was first described as a human pathogen in 1984, and has been associated with metastatic endophthalmitis and one previously reported case of sclerokeratitis.

METHODS

We report a case of S. prolificans sclerokeratitis in the setting of late scleral necrosis complicating pterygium surgery with adjunctive beta-irradiation.

RESULTS

A poor clinical response to topical natamycin and amphotericin B, and systemic itraconazole and ketoconazole was encountered. Enucleation was required, with subsequent microbiological cure. Pathological correlation is described.

CONCLUSIONS

S. prolificans infections often respond poorly to medical therapy. Early surgical intervention is indicated in culture-proven scleritis due to Scedosporium prolificans.

Recurrent corneal infections in a patient with the acquired immunodeficiency syndrome

A 29-year-old female intravenous drug abuser infected with the human immunodeficiency virus suffered recurrent, bilateral corneal infections over an 11-month period. Multiple infectious organisms were responsible, including capnocytophaga species, Candida albicans, Staphylococcus aureus, coagulase-negative staphylococcus, and a-streptococcus. One eye was eviscerated because of corneal perforation and loss of vision; the second eye has maintained good vision. Predisposing factors usually associated with corneal infections were absent. Treatment was complicated by extremely poor patient compliance, ongoing intravenous drug abuse, and concurrent multiple extraocular medical problems.

Fungal invasion of seven hydrophilic contact lenses

In six patients we reviewed the clinical, microbiologic, and histopathologic findings of seven hydrophilic contact lenses that had been infiltrated by fungi. Three patients had visual blurring or irritation and redness while wearing a contaminated lens; of these, two were unaware of any lens deposits. Three of the lenses from two patients were spares kept in storage for six months and one year, respectively. One contaminated lens had been torn and was kept in a case while a loaner lens was worn. Culture of this lens grew Cladosporium species. The contact lens case from one patient grew Penicillium species. Gross pathologic inspection disclosed multiple brown deposits in five lenses, multiple gray infiltrates in one lens, and a white infiltrate in one lens. Light microscopic examination disclosed partial-thickness (three lenses) or full-thickness (four lenses) invasion of the lens matrix by fungi, which contained granular, brown pigment in six lenses.

Corneal complications associated with the use of crack cocaine

BACKGROUND

A case series of patients with corneal complications associated with crack cocaine use is presented. Patients had infectious keratitis or sterile epithelial defects.

METHODS

Entry criteria into this series included the presence of an infectious corneal ulcer or sterile epithelial defect after the patient used crack cocaine routinely. Patients were prospectively identified from July 1, 1989 to June 30, 1991.

RESULTS

Fourteen patients with crack-related corneal problems were identified. In 10 patients with infectious corneal ulcers, both bacterial and fungal organisms were isolated, and patients were treated with appropriate antimicrobial therapy. The group of patients with sterile corneal epithelial defects were seen after they had rubbed their eyes vigorously after crack cocaine use. The epithelial defects were treated and healed without complication.

CONCLUSION

Crack cocaine users appear to represent a unique subset of young patients predisposed to infectious keratitis and corneal epithelial defects. A number of hypotheses are offered to explain this effect. Both ophthalmologists and the general public should be aware of these severe corneal problems associated with the use of crack cocaine.

Human infectious corneal ulcer caused by Pythium insidiosum

Pythium insidiosum is a fungus-like organism known to infect a variety of animals. In humans, the few known cases involving Pythium have included arterial infections and cellulitis. We present what we believe to be the first case of P. insidiosum recovered from a human corneal ulcer. The organism is difficult to isolate, causing delays in diagnosis. It is also resistant to the usual antifungal medications, making surgical excision the treatment of choice.

Infectious endophthalmitis

The internist or family medicine consultant can have an important role in the management of endophthalmitis. Even though intraocular antimicrobial therapy is the most effective method of treatment, the consultant can assist in the selection of systemic antibiotic agents and in the monitoring of systemic side effects of the treatment. In addition, the consultant can be called on to evaluate patients with endogenous endophthalmitis for systemic involvement. The joint efforts of the ophthalmologist and consultant should allow optimal treatment in an attempt to improve the visual prognosis for these devastating ocular infections.

Preseptal and orbital cellulitis

The patient with a tender, erythematous, swollen eyelid represents a complex clinical challenge to the physician, who must arrive at a correct diagnosis from numerous differential possibilities. Knowledge of the anatomy of the orbit and surrounding structures and proper clinical and radiologic examination are necessary to accurately diagnose these conditions. Proper selection of antibiotic therapy and timely surgical intervention, directed at both the orbital infection and the underlying condition, are essential to avoid serious morbidity from these infections. This article reviews in detail preseptal cellulitis, Hemophilus influenzae type B infection in children, orbital infection related to paranasal sinusitis, orbital infection from other causes, and mycotic infections of the orbit.

Atypical presentation of fungal dacryocystitis. A report of two cases

BACKGROUND

Candida albicans has only rarely been implicated in nasolacrimal duct obstruction. Its association with dacryoliths is well known, but it is unclear whether it is an etiologic factor or is present as a result of the obstruction.

FINDINGS

The authors report 2 cases of fungal dacryocystitis that were not associated with dacryolith formation and where Candida species appear to be the primary etiologic agent.

CONCLUSION

The possibility of a fungal infection should be considered in the evaluation of "routine" chronic dacryocystitis, particularly in the presence of corneal ulceration or postoperative endophthalmitis, as prompt initiation of appropriate therapy may be crucial.

Pseudallescheria boydii keratitis

We treated a case of post-traumatic keratitis caused by the soil saprophyte, Pseudallescheria boydii. The injury was caused by a wood splinter which produced a perforating corneal laceration that was primarily repaired. Signs of corneal infection were not evident until the fourth postoperative week. The organism was eradicated by topical miconazole and natamycin. Subsequent penetrating keratoplasty combined with cataract extraction and intraocular lens implantation has achieved a good visual outcome.

Mycotic keratitis: a study in coastal Karnataka

Fungi were isolated from 67 cases out of the 295 cases of corneal ulcers investigated. Aspergillus species and species of Candida were the major fungal members isolated. Allescheria boydii was isolated from 3 cases, having no previous history of injury to the eye or infection with bacterial or viral agents. A boydii corneal infection is a rare occurrence. Higher incidence of mystic keratitis was seen among females than males. No relationship to seasonal changes could be established. Bacterial infection was associated in 46. 27% of the cases of mycotic keratitis and Staphylococcus was the predominant bacterial pathogen observed.