Unilateral fungal and mycobacterial keratitis after simultaneous laser in situ keratomileusis

Successful treatment of Keratitis caused by Mycobacterium chelonae and an overview of previous cases in Europe

INTRODUCTION AND PURPOSE

Mycobacterium (M.) chelonae is responsible for a half of relatively rare nontuberculous mycobacteria (NTM) keratitis. We report a case of M. chelonae keratitis in a woman following sclerocorneal suture extraction after cataract surgery.

RESULTS

A 70-year-old woman presented with a red eye and corneal infiltration of her left eye six weeks following sclerocorneal suture extraction after an elective cataract surgery in another institute. She complained of a sharp, cutting pain and photophobia. Since initial corneal scrapes and conjunctival swabs proved no pathogen using culture and PCR methods, non-specific antibiotics and antifungal agents were administered. As keratitis was complicated by an inflammation in the anterior chamber and vitreous, samples of the vitreous fluid were sent for microbiologic examination. DNA of Epstein-Barr virus (EBV) was repeatedly detected. Since the intrastromal abscess had formed, corneal re-scrapings were performed and M. chelonae was detected using culture, MALDI-TOF MS and PCR methods. Therapy was changed to a combination of oral and topical clarithromycin, intravitreal, topical and intracameral amikacin, and oral and topical moxifloxacin. The successful therapy led to stabilization. The optical penetrating keratoplasty was performed and no signs of the infection recurrence were found.

CONCLUSIONS

The diagnosis of nontuberculous mycobacterial keratitis is difficult and often delayed. An aggressive and prolonged antimicrobial therapy should include systemic and topical antibiotics. Surgical intervention in the form of corneal transplantation may be required in the active and nonresponsive infection. In the presented case this was necessary for visual rehabilitation due to scarring.

Nontuberculous Mycobacterial Ocular Infections: A Systematic Review of the Literature

Nontuberculous or atypical mycobacterial ocular infections have been increasing in prevalence over the past few decades. They are known to cause periocular, adnexal, ocular surface and intraocular infections and are often recalcitrant to medical therapy. These infections can potentially cause detrimental outcomes, in part due to a delay in diagnosis. We review 174 case reports and series on nontuberculous mycobacterial (NTM) ocular infections and discuss etiology, microbiology, risk factors, diagnosis, clinical presentation, and treatment of these infections. History of interventions, trauma, foreign bodies, implants, contact lenses, and steroids are linked to NTM ocular infections. Steroid use may prolong the duration of the infection and cause poorer visual outcomes. Early diagnosis and initiation of treatment with multiple antibiotics are necessary to achieve the best visual outcome.

Post-laser in situ keratomileusis interface fungal keratitis

PURPOSE

To report outcomes of post-laser in situ keratomileusis (LASIK) interface filamentous fungal keratitis.

METHODS

This retrospective interventional case series included 6 eyes of 5 patients with microbiologically proven post-LASIK interface fungal keratitis from August 2008 to August 2013. Patients presenting with concurrent bacterial/viral keratitis, systemic illness, prior ocular pathology, or those without a minimum follow-up of 3 months were excluded. Every case underwent microbiological scrapings from residual bed and undersurface of the flap after flap lift at presentation followed by voriconazole interface wash. Flap amputation was performed when required. The outcome measure was complete resolution of infection.

RESULTS

The mean age was 24 ± 3.1 years. The male:female ratio was 4:1. The mean interval between LASIK and symptom onset was 4.16 ± 2 days; and the mean interval between symptom onset and patient referral was 3.16 ± 1.16 days. Interface scrapings showed filamentous fungal filaments in KOH wet mount. The culture grew Aspergillus in case 1 and case 5. Infiltrated LASIK flap needed to be amputated in 4 eyes of 3 patients. Voriconazole wash (100 μg/mL) of the stromal bed was performed in all cases. A positive response to therapy with resolution of infection was seen in all cases at a mean of 6.5 ± 4.6 days. No intraoperative or postoperative complications after interface scraping or voriconazole wash were observed. The final best-corrected visual acuity ranged from 20/20 to 20/80 at a mean follow-up of 9.1 ± 6.5 months.

CONCLUSIONS

Post-LASIK interface fungal filamentous keratitis can present early and gives good outcomes with early microbiological diagnosis and appropriate management. Voriconazole is an efficient and probably safe adjunct in the armamentarium of corneal surgeons to treat such cases.

Nontuberculous mycobacterial ocular and adnexal infections

The nontuberculous (also called "atypical") mycobacteria have become increasingly important causes of systemic as well as ocular morbidity in recent decades. All ocular tissues can become infected with these organisms, particularly in patients who are predisposed following ocular trauma, surgery, use of corticosteroids, or are immunocompromised. Because of their relative resistance to available antibiotics, multidrug parenteral therapy continues to be the mainstay of treatment of more serious ocular and adnexal infections caused by nontuberculous mycobacteria (NTM). Periocular cutaneous, adnexal, and orbital NTM infections remain rare and require surgical debridement and long-term parenteral antibiotic therapy. NTM scleritis may occur after trauma or scleral buckling and can cause chronic disease that responds only to appropriate antibiotic therapy and, in some cases, surgical debridement and explant removal. NTM infectious keratitis following trauma or refractive surgical procedures is commonly confused with other infections such as Herpes simplex keratitis and requires aggressive topical therapy and possible surgical debridement, particularly in those cases occuring after laser in situ keratomileusis. Only 18 cases of endophthalmitis due to NTM have been reported. Systemic and intraocular antibiotic therapy and multiple vitrectomies may be needed in NTM endophthalmitis; the prognosis remains poor, however. Disseminated NTM choroiditis in acquired immune deficiency syndrome patients with immune reconstitution during highly active anti-retroviral therapy is a rare infection that can present as a necrotizing chorioretinitis with dense vitritis, mimicking many other entities and needs to be recognized so that timely, life-saving treatment can be administered. Regardless of which ocular tissue is infected, all NTM ocular infections present similar challenges of recognition and of therapeutic intervention. We clarify diagnosis and delineate modern, effective therapy for these conditions.

Bilateral deep anterior lamellar keratoplasty for the management of bilateral post-LASIK mycobacterial keratitis

A 25-year-old Vietnamese man who had bilateral simultaneous laser in situ keratomileusis (LASIK) for moderate myopia developed bilateral Mycobacterium abscessus keratitis that was treated with intensive medical therapy, flap removal, superficial keratectomy, and, following disease progression, therapeutic deep anterior lamellar keratoplasty (DALK). To our knowledge, this is the first reported case of bilateral post-LASIK mycobacterial keratitis successfully treated with DALK.

Recalcitrant Post-LASIK Mycobacterium chelonae Keratitis Eradicated after the Use of Fourth-Generation Fluoroquinolone

OBJECTIVE

To report a patient with Mycobacterium chelonae keratitis after LASIK and discuss therapeutic measures.

DESIGN

Interventional case report and literature review.

INTERVENTION

A healthy, 25-year-old man presented 6 weeks after LASIK with infectious keratitis in the left eye. Scrapings were obtained from the central stromal bed after lifting the flap and inoculated on culture media.

MAIN OUTCOME MEASURES

Response to medical treatment.

RESULTS

Mycobacterium chelonae was identified from stromal bed scrapings. The protracted course of the infection necessitated surgical debridement and flap amputation with slow and suboptimal response to prolonged (14 weeks) treatment with topical amikacin 3.3%, clarithromycin 1%, and levofloxacin 0.5%. The substitution of levofloxacin 0.5% with gatifloxacin 0.3% resulted in closure of the epithelial defect within 1 week and resolution of the infiltrates in 3 weeks. The combined regimen of gatifloxacin 0.3%, amikacin 3.3%, and clarithromycin 1% was continued for a total of 4 months. The patient remains infection free 1 year after stopping all antibiotics.

CONCLUSION

Treatment of post-LASIK nontuberculous mycobacteria remains a challenge. Institution of combination therapy including fortified amikacin, clarithromycin 1%, and a fourth-generation fluoroquinolone appeared to be beneficial in this patient.

Bacillus megaterium Delayed Onset Lamellar Keratitis After LASIK

PURPOSE

To report the history and clinical presentation of a 23-year-old man who developed delayed onset lamellar keratitis in his right eye 2 weeks after uneventful LASIK for correction of myopia.

METHODS

Initial clinical presentation suggested an infectious etiology, which led to therapeutic elevation of the LASIK flap and further microbiologic investigation with bacterial cultures.

RESULTS

Bacterial cultures revealed Bacillus megaterium, which was sensitive to all antibiotics against which it was tested. Twenty-four hours after initiating aggressive topical and oral antibiotic therapy, symptomatic relief occurred in the affected eye. The patient's uncorrected final visual acuity at 1-year follow-up was 20/15 in the right eye, and the stromal bed developed a faint peripheral non-visually significant scar.

CONCLUSIONS

This case is an unusual presentation and course for microbial keratitis following LASIK, which occurred despite aseptic technique and fluoroquinolone antibiotic prophylaxis. Following refractive surgery one should be prepared to culture the lamellar interface in cases of suspected microbial keratitis and begin aggressive antibiotic therapy.

Fourth-generation fluoroquinolones in the treatment of mycobacterial infectious keratitis after laser-assisted in situ keratomileusis surgery

CASE REPORT

Infectious keratitis after laser-assisted in situ keratomileusis (LASIK) is a rare complication that may be challenging to diagnose and treat. We discuss some of the reasons for difficulties diagnosing postoperative atypical or nontuberculous mycobacterial infection and establishing an effective treatment, with reference to reports of comparative antibacterial activity of the most commonly used antibiotics.

COMMENTS

To the best of our knowledge, we are the first to report the use of the fourth-generation fluoroquinolone moxifloxacin in combination therapy for the successful treatment of this condition.

Nocardia keratitis after laser in situ keratomileusis: Clinicopathologic correlation

A case of Nocardia asteroides keratitis occurring 3 weeks after laser in situ keratomileusis (LASIK) in a nontraumatized eye is reported. The patient presented with decreased vision, inflammation, and stromal melting of the LASIK flap, discrete infiltrates, and an anterior chamber cellular reaction. Cultures for acid-fast bacteria grew Nocardia asteroides after 5 days. Infection progressed despite treatment with topical antibiotics and eventually required penetrating keratoplasty (PKP). Postoperatively, the patient was placed on moxifloxacin, a fourth-generation flouroquinolone. The patient experienced a recurrence of Nocardia keratitis at the graft-host interface 2 months after the PKP. This eventually resolved with a combination of topical moxifloxacin and imipenem therapy.

In Vitro Activity of Fluoroquinolones Against Mycobacterium abscessus and Mycobacterium chelonae Causing Infectious Keratitis After LASIK in Brazil

PURPOSE

To evaluate the in vitro activity of fluoroquinolones against Mycobacterium abscessus and Mycobacterium chelonae isolated from outbreaks of infectious keratitis in Brazil.

MATERIAL AND METHODS

Micobacterial isolates were recovered from infectious keratitis cases related outbreaks that occurred in Brazil after LASIK for myopia. Two outbreaks occurred in Rio de Janeiro in 1998 and 1999, and 3 in São Paulo between 2000 and 2003. All laboratorial analysis, including molecular identification and antibiotic susceptibility testing with determination of the minimum inhibitory concentration (MIC) levels for ciprofloxacin, ofloxacin, gatifloxacin, and moxifloxacin, were performed at Universidade Federal de São Paulo in Brazil.

RESULTS

Fifteen samples were identified as M. chelonae, and 3 were identified as M. abscessus. The outbreaks studied were designated SP-1 in 2000; SP-2 in 2000-2001; and SP-3 in 2003, R1 in 1988 and R2 in 1999. All but 1 of the M. chelonae were resistant to all fluoroquinolones with an MIC90 greater than 32 microg/mL. The only susceptible isolate had MIC levels for ciprofloxacin, ofloxacin, gatifloxacin, and moxifloxacin of 0.38 microg/mL, 0.032 microg/mL, 0.047 microg/mL, and 0.19 microg/mL, respectively. MIC levels for all 3 M. abscessus isolates tested were greater then 32 microg/mL for all fluoroquinolones tested.

CONCLUSIONS

Fluoroquinolone MICs for 17 M. abscessus and M. chelonae isolates recovered from infectious keratitis cases in Brazil indicate that they are not susceptible to these drugs in vitro. Further studies to investigate the in vivo effectiveness of fluoroquinolones against mycobacteria are required because in vitro tests do not support their use in the treatment of micobacterial keratitis in this particular geographic area.

Nontuberculous (atypical) mycobacterial keratitis after LASIK: current status and clinical implications

PURPOSE

Corneal infection with unfamiliar organisms such as nontuberculous (atypical) mycobacteria after laser in situ keratomileusis (LASIK) can be a significant clinical problem, and mismanagement of such corneal infection in an otherwise healthy, young individual can lead to significant medicolegal issues for the refractive surgeon. Because nontuberculous (atypical) mycobacterial keratitis is the most common infection after LASIK, the refractive surgeon should be aware of all aspects of this dreaded infection to be better prepared to manage such cases.

METHODS

Literature search.

RESULTS/CONCLUSIONS

This article provides a comprehensive compilation of all reported cases of nontuberculous (atypical) mycobacterial keratitis in the English literature and provides some useful recommendations for the clinical management of such corneal infection after LASIK.

Infections following laser in situ keratomileusis: an integration of the published literature

Infections occurring after laser in situ keratomileusis (LASIK) surgery are uncommon, but the number of reports have steadily increased in recent years. This systematic, comprehensive review and analysis of the published literature has been performed in order to develop an integrative perspective on these infections. We have stratified the data by potential associations, microbiology, treatment, and the degree of visual loss, using Fisher's exact tests and Student's t-tests for analysis. In this review, we found that Gram-positive bacteria and mycobacterium were the most common causative organisms. Type of postoperative antibiotic and steroid use was not associated with particular infecting organisms or severity of visual loss. Gram-positive infections were more likely to present less than 7 days after LASIK, and they were associated with pain, discharge, epithelial defects, and anterior chamber reactions. Fungal infections were associated with redness and tearing on presentation. Mycobacterial infections were more likely to present 10 or more days after LASIK surgery. Moderate or severe visual reductions in visual acuity occurred in 49.4% of eyes. Severe reductions in visual acuity were significantly more associated with fungal infections. Flap lift and repositioning preformed within 3 days of symptom onset may be associated with better visual outcome.

Nattrassia mangiferae keratitis after laser in situ keratomileusis

A 32-year-old man had photophobia and blurred vision 2 weeks after uneventful laser in situ keratomileusis to correct myopia. He was treated with steroids for suspected diffuse lamellar keratitis, antiherpetics, and antibiotic eyedrops, but the condition worsened and the patient developed further blurred vision, an inflamed eye, and pain. When referred to us, the patient had an extensive corneal ulcer with hypopyon and mycelia were reported in scrapings of the ulcer bed. Nattrassia mangiferae (Hendersonula toruloidea) was cultured from the specimen. The patient was treated with antifungal agents and 2 penetrating keratoplasties. At the last examination, the uncorrected visual acuity was 20/200.