Recurrent fungal keratitis and endophthalmitis

Molecular epidemiology of clinical filamentous fungi in Qatar beyond Aspergillus and Fusarium with notes on the rare species

Due to an increasing number of patients at risk (i.e., those with a highly compromised immune system and/or receiving aggressive chemotherapy treatment), invasive fungal infections (IFI) are increasingly being reported and associated with high mortality rates. Aspergillus spp., particularly A. fumigatus, is the major cause of IFI caused by filamentous fungi around the world followed by Fusarium spp., however, other fungi are emerging as human pathogens. The aim of this study was to explore the epidemiology and prevalence of the non-Aspergillus and non-Fusarium filamentous fungi in human clinical samples over an 11-year period in Qatar using molecular techniques. We recovered 53 filamentous fungal isolates from patients with various clinical conditions. Most patients were males (75.5%), 9.4% were immunocompromised, 20.7% had IFI, and 11.3% died within 30 days of diagnosis. The fungal isolates were recovered from a variety of clinical samples, including the nasal cavity, wounds, respiratory samples, body fluids, eye, ear, tissue, abscess, and blood specimens. Among the fungi isolated, 49% were dematiaceous fungi, followed by Mucorales (30%), with the latter group Mucorales being the major cause of IFI (5/11, 45.5%). The current study highlights the epidemiology and spectrum of filamentous fungal genera, other than Aspergillus and Fusarium, recovered from human clinical samples in Qatar, excluding superficial infections, which can aid in the surveillance of uncommon and emerging mycoses.

Surgical treatment of Metarhizium anisopliae sclerokeratitis and endophthalmitis

A 55-year-old nurse was referred with a 5-month history of right eye corneal abscess. The initial injury occurred when doing lawn work. The infection worsened despite multiple antibiotic, antiviral, and steroid treatments. Visual acuity was limited to hand motion. On examination, there was keratitis, ocular hypertension, and a secondary cataract. Corneal scrapings grew a filamentous fungus, identified as Metarhizium anisopliae (MA). Despite intensive antifungal treatment with topical, intravitreous, and systemic voriconazole, purulent corneal melting and scleritis with endophthalmitis rapidly appeared. An emergency surgical procedure including sclerocorneal transplantation, cataract surgery, a pars plana vitrectomy using temporary keratoprosthesis, and scleral crosslinking was necessary. One year after the surgery, there was no recurrence of infection. Functional outcome remained very poor. This is the first case of sclerokeratitis and endophthalmitis caused by MA ever reported. The infection was successfully treated with an aggressive combination of medical and surgical treatments.

Infectious keratitis progressing to endophthalmitis: a 15-year study of microbiology, associated factors, and clinical outcomes

PURPOSE

To describe the incidence, microbiology, associated factors, and clinical outcomes of patients with infectious keratitis progressing to endophthalmitis.

DESIGN

Nonrandomized, retrospective, consecutive case series.

PARTICIPANTS

All patients treated for culture-proven keratitis and endophthalmitis between January 1, 1995 and December 31, 2009, at the Bascom Palmer Eye Institute.

METHODS

Ocular microbiology and medical records were reviewed on all patients with positive corneal and intraocular cultures over the period of the study. Univariate analysis was performed to obtain P values described in the study.

MAIN OUTCOME MEASURES

Microbial isolates, treatment strategies, and visual acuity (VA) outcomes.

RESULTS

A total of 9934 corneal cultures were performed for suspected infectious keratitis. Only 49 eyes (0.5%) progressed to culture-proven endophthalmitis. Fungi (n = 26) were the most common responsible organism followed by gram-positive bacteria (n = 13) and gram-negative bacteria (n = 10). Topical steroid use (37/49 [76%]) was the most common associated factor identified in the current study, followed by previous surgery (30/49 [61%]), corneal perforation (17/49 [35%]), dry eye (15/49 [31%]), relative immune compromise (10/49 [20%]), organic matter trauma (9/49 [18%]), and contact lens wear (3/49 [6%]). There were 27 patients in whom a primary infectious keratitis developed into endophthalmitis, and 22 patients in whom an infectious keratitis adjacent to a previous surgical wound progressed into endophthalmitis. Patients in the primary keratitis group were more likely to be male (22/27 [81%] vs 8/22 [36%]; P = 0.001), have history of organic matter trauma (8/27 [30%] vs 1/22 [5%]); P = 0.030), and have fungal etiology (21/27 [78%] vs 5/22 [23%]; P<0.001). Patients in the surgical wound-associated group were more likely to use topical steroids (20/22 [91%] vs 17/27 [63%]; P = 0.024). A VA of ≥ 20/50 was achieved in 7 of 49 patients (14%), but was <5/200 in 34 of 49 (69%) at last follow-up. Enucleation or evisceration was performed in 15 of 49 patients (31%).

CONCLUSIONS

Progression of infectious keratitis to endophthalmitis is relatively uncommon. The current study suggests that patients at higher risk for progression to endophthalmitis include patients using topical corticosteroids, patients with fungal keratitis, patients with corneal perforation, and patients with infectious keratitis developing adjacent to a previous surgical wound. Patients with sequential keratitis and endophthalmitis have generally poor visual outcomes.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Case report of Acremonium intraocular infection after cataract extraction

A 64-year-old woman was referred to our clinic for the treatment of chronic uveitis in her left eye, which had started two weeks after an uncomplicated cataract extraction. She was treated with topical steroids with an initially good response, yet she subsequently developed severe inflammation and plaque-like material around the intraocular lens, despite continuous steroid therapy. She underwent pars plana vitrectomy, smear and culture of the aqueous and vitreous fluids, and intravitreal antibiotic injection under the impression of Propionibacterium acne (P. acne) endophthalmitis. As a result of the smear and culture of the vitreous fluid identified as an Acremonium species, she was treated with intravenous amphotericin B injections for five days, followed by oral voriconazole administration. During the post-operative 18-month follow-up, she was stable without significant relapse of uveitis. In this case, the best correction of visual acuity was an improvement from 20/40 to 20/20.

Corneal Concentrations following Systemic Administration of Amphotericin B and Its Lipid Preparations in a Rabbit Model

BACKGROUND

Amphotericin B (AmB) and various lipid formulations of AmB are available for the treatment of fungal infections of the eye. Currently, the recommended route of administration for the treatment of fungal keratitis is by topical application. Nevertheless, because of the risk of a difficult to treat exogenous fungal endophthalmitis, a combined topical and systemic treatment is frequently given when treating deep fungal keratitis. To date, little is known about the pure corneal availability of these drugs following systemic treatment. In this study, the corneal concentration following 7 daily doses of parenteral AmB lipid complex (ABLC) or liposomal AmB (L-AmB) was compared to that of AmB deoxycholate (D-AmB) in a rabbit model.

METHODS

Following induction of uveitis in one rabbit eye by intravitreal injection of endotoxin, daily doses of D-AmB (1 mg/kg), ABLC (5 mg/kg) or L-AmB (5 mg/kg) were given intravenously on 7 consecutive days. Five or more rabbits per treatment were used. AmB concentrations were determined by high-performance liquid chromatography (HPLC) in corneas collected at autopsy 24 h after the 7th and final dose. Data were analyzed using the Mann-Whitney U test.

RESULTS

After 7 days of treatment, mean corneal concentrations of AmB in the inflamed eyes were significantly higher (2.38 +/- 1.47 microg/g; p < 0.01) following treatment with L-AmB compared with ABLC (<0.1 microg/g) and D-AmB (0.46 +/- 0.2 microg/g). No AmB could be detected in the corneas of the non-inflamed eyes.

CONCLUSION

In our rabbit model, AmB penetration into the cornea was significantly higher after systemic administration of L-AmB compared with conventional D-AmB or ABLC.

Therapeutic penetrating keratoplasty in severe fungal keratitis using cryopreserved donor corneas

AIMS

To investigate whether cryopreserved donor cornea could be used for therapeutic penetrating keratoplasty (PKP) to eradicate the infection, obviate complications, and preserve anatomical integrity in severe fungal keratitis.

METHODS

In this retrospective, consecutive case series, 45 eyes of 45 patients with severe fungal keratitis, which exhibited anterior chamber collapse, corneal perforation, and/or large suppurative corneal infiltrate, received therapeutic PKP after removal of the infected corneal tissue, irrigation of the anterior chamber by 0.2% fluconazole solution, iris dissection of fibrinoid membrane, and iridectomy and therapeutic PKP using corneas cryopreserved at -20 degrees C.

RESULTS

Among 45 eyes, 39 eyes (86.7%) were successfully eradicated the fungal infection without recurrence and maintained their anatomical integrity without any complication. Four of 45 eyes (8.9%) showed postoperative rise of intraocular pressure, of which three were controlled with subsequent antiglaucoma surgeries, whereas one eye needed additional antiglaucoma medications. Two of 45 eyes (4.4%) were enucleated because of uncontrollable fungal infection and secondary retinal detachment, respectively. 23 eyes received subsequent optical PKP and, among them, 21 maintained clear corneal grafts and two suffered from graft failure due to allograft rejections.

CONCLUSION

Cryopreserved donor corneas are effective substitutes in therapeutic PKP to control severe fungal corneal infection and preserve the global integrity, and may offer additional advantages over conventional PKP in reducing allograft rejection, eradicating fungal infection during the postoperative period, and improving the success of optical PKP for visual rehabilitation.