Scedosporium Keratitis: An Experience From a Tertiary Eye Hospital in South India

Ocular scedosporiosis: A case series

Purpose

To report five cases of ocular scedosporiosis with associated predisposing factors, treatment courses, and clinical outcomes.

Observation

This case series consists of 5 patients diagnosed with ocular scedosporiosis. Two patients were female and 3 were male. The average age was 68.4 years (range 53-85). Four of the 5 had a clear history of ocular surgery or ocular trauma with organic foreign material. Two developed sclero-keratitis. Two had cornea-only involvement. There was 1 scleritis-only case. Patients with scleritis required topical and systemic treatment. Patients with only keratitis were treated topically. The two patients with sclero-keratitis ultimately progressed to eye removal despite maximal therapy.

Conclusion and importance

Ocular scedosporiosis is exceedingly rare, especially in the Unites States. We highlight similarities and differences of five ocular scedosporiosis cases. Most cases involved either ocular surgery or contamination with ground or plant matter. This case series highlights the challenge of the diagnosis and the aggressivity of this disease.

Scedosporiosis and lomentosporiosis: modern perspectives on these difficult-to-treat rare mold infections

SUMMARYAlthough Scedosporium species and Lomentospora prolificans are uncommon causes of invasive fungal diseases (IFDs), these infections are associated with high mortality and are costly to treat with a limited armamentarium of antifungal drugs. In light of recent advances, including in the area of new antifungals, the present review provides a timely and updated overview of these IFDs, with a focus on the taxonomy, clinical epidemiology, pathogenesis and host immune response, disease manifestations, diagnosis, antifungal susceptibility, and treatment. An expansion of hosts at risk for these difficult-to-treat infections has emerged over the last two decades given the increased use of, and broader population treated with, immunomodulatory and targeted molecular agents as well as wider adoption of antifungal prophylaxis. Clinical presentations differ not only between genera but also across the different Scedosporium species. L. prolificans is intrinsically resistant to most currently available antifungal agents, and the prognosis of immunocompromised patients with lomentosporiosis is poor. Development of, and improved access to, diagnostic modalities for early detection of these rare mold infections is paramount for timely targeted antifungal therapy and surgery if indicated. New antifungal agents (e.g., olorofim, fosmanogepix) with novel mechanisms of action and less cross-resistance to existing classes, availability of formulations for oral administration, and fewer drug-drug interactions are now in late-stage clinical trials, and soon, could extend options to treat scedosporiosis/lomentosporiosis. Much work remains to increase our understanding of these infections, especially in the pediatric setting. Knowledge gaps for future research are highlighted in the review.

Challenges in the diagnosis and management of atypical fungal keratitis during the COVID-19 pandemic: a case series

Fungal keratitis is a time-sensitive ocular infection that often requires a high index of suspicion followed by intensive medical/surgical interventions to achieve a successful clinical outcome. COVID-19 pandemic-related restrictions, necessitated the modification of conventional protocols and guidelines associated with the treatment of keratomycosis. We report four cases of atypical fungal keratitis with poorly differentiated clinical characteristics. The challenges faced during their management were (1) the dilemma of clinically differentiating fungal (Scedosporium and Purpureocillium lilacinum) and bacterial keratitis; (2) treatment of Scedosporium and Trichosporon keratitis with natamycin monotherapy; (3) mixed infection of Candida albicans and Aureobasidium pullulans and continuing medications before rescraping the corneal ulcer against the recommended treatment guidelines; (4) phenotypic identification and differentiation among morphologically resembling fungi; and (5) decision making arising out of disparities between KOH and fungal culture results. Three patients responded well to conservative treatments. The fourth patient underwent therapeutic keratoplasty but was lost to follow-up due to travel-related pandemic restrictions. This case series seeks to broaden the clinician's knowledge of rare and emerging moulds as presumptive aetiologies of keratomycosis. It also intends to emphasize the significance of early microbiological investigations, (direct microscopy and culture), in resource-limited settings, for initiating empirical treatment for a better visual prognosis.

Clinical profile and treatment outcomes of Fusarium keratitis

Purpose:

To determine the seasonality, clinical profile, and treatment outcome of Fusarium keratitis.

Methods:

A retrospective medical chart review of 97 patients with culture-proven Fusarium keratitis at a tertiary eye care institution from January 2018 to December 2019.

Results:

The median (SD) age at enrollment was 44.6 (16) years; 75 (79.8%) of them were male. Presence of infiltrate less than 4 mm² at baseline indicated 4.4 times the odds of achieving final BCVA more than 20/60 (95% CI: 1.4–13.3; P = 0.008). The absence of surgical management indicated 8.1 times the odds of achieving final BCVA of more than 20/60 (95% CI: 0.9–71.5; P = 0.06). The visual acuity at presentation, duration between symptoms and presentation, history of ocular trauma, previous use of topical medications, and presence of hypopyon were not identified as significant predictors of final BCVA in the multivariable regression analysis.

Conclusion:

Smaller infiltrate size and absence of surgical management are the significant predictors of good visual outcome. Visual outcome of Fusarium keratitis is poor, and a significant number of patients did not respond to anti-fungal therapy and had to undergo surgeries. To the best of our knowledge, this is the largest case series on Fusarium keratitis to date.

Fungal keratitis: A review of clinical presentations, treatment strategies and outcomes

Infectious keratitis is a significant cause of corneal blindness worldwide. Although less prevalent in the developed world, cases of fungal keratitis account for almost half of all keratitis cases, occurring in the developing countries. These cases are one of the most refractory types of infectious keratitis and present various challenges to the treating physician such as delayed presentation, long waiting time for culture positivity, limited availability effective antifungal drugs, prolonged duration for response to therapy, a highly variable spectrum of anti-fungal drug sensitivity and a high recurrence rate following keratoplasty. The advent of rapid diagnostic tools, molecular methods, in vitro anti-fungal drug sensitivity testing, alternatives to natamycin, targeted drug delivery and most importantly the results of large randomized controlled trials have significantly improved our understanding and approach towards the diagnosis and management of cases with fungal keratitis. Overall, Aspergillus and Fusarium species are the most common causes ones of fungal keratitis. History of antecedent trauma is a significant predisposing factor. Corneal scrapings for microscopic evaluation and culture preparation, is the standard of care for establishing the diagnosis of fungal keratitis. Molecular identification of cultures offers accurate identification of fungal pathogens, especially the rare species. Natamycin is an approved first-line drug. Voriconazole is the best alternative, especially for non-fusarium cases. Management involves administration of drugs usually by a combination of various routes, the treatment regimen being individualized depending upon the response to therapy. Photodynamic therapy is a newer treatment modality, being tried for non-responsive cases, before resorting to a therapeutic graft.

Fungal keratitis caused by Pseudallescheria boydii: clinical and mycological characteristics

Background

Pseudallescheria keratitis is rare but important type of fungal keratitis because of the inherently resistance of the organism to many existing antifungal agents.

Methods

Slit-lamp and confocal microscopy were used for clinical examinations. Fungal isolates were identified based on morphological characteristics and DNA sequence of the internal transcribed spacer region (ITS). In vitro antifungal susceptibility testing for fungal isolates was performed according to the Clinical and Laboratory Standards Institute (CLSI, M38-A2).

Result

All patients had a history of ocular trauma. In clinical examination hypopion were seen in three patients. The main antifungal medications were topical voriconazole. After treatment the visual acuity of all patients improved in 2–3 weeks.

Conclusion

All four patients of Pseudallescheria keratitis had similar clinical features. Accurate and rapid identification of species should be helpful in treating p. boydii keratitis.

Predictive Factors for Resolution of Dematiaceous Fungal Keratitis

PURPOSE

To ascertain the clinicomicrobiological correlation and evaluate the prognostic factors associated with medical resolution in cases of Curvularia, Alternaria, and Scedosporium keratitis.

METHODS

A retrospective review of clinical and microbiological records of culture-proven cases of Curvularia, Alternaria, and Scedosporium keratitis from 2017 to 2019 was performed. Multivariate logistic regression analyses were performed to assess the predictive factors for medical resolution.

RESULTS

There were a total of 79 eyes of 79 patients. Among these, there were 56 (70.8%), 15 (18.9%), and 8 (10.1%) patients with Curvularia, Scedosporium, and Alternaria keratitis, respectively. Clinical resolution with medical treatment was achieved in 46 of 56 (82.1%) patients with Curvularia keratitis, 8 of 15 (53.3%) patients with Scedosporium, and 7 of 8 (87.5%) patients with Alternaria keratitis. In comparison between Curvularia and Scedosporium, macroscopic pigmentation [18/56 (32.1%)] of anterior stromal plaque-like infiltrate [20/56 (35.7%)] was clinically more in cases with Curvularia, whereas larger diameter of the infiltrate, P = 0.002, posterior stromal infiltrate (40%), P = 0.03, and hypopyon, P = 0.009, were more common with Scedosporium. Multivariate logistic regression analysis, by backward elimination, showed that maximum dimension of the infiltrate (P = 0.01; odds ratio = 0.52, 95% confidence interval, 0.31-0.86) and presence of a hypopyon (P = 0.02; odds ratio = 0.12, 95% confidence interval, 0.02-0.71) were significant factors that were not favoring medical resolution.

CONCLUSIONS

Larger size of the infiltrate, posterior stromal involvement, and presence of a hypopyon are poor prognostic indicators among all 3 species. Variation in species is not a predictor of clinical resolution.

[Scedosporium apiospermum-a rare pathogen of keratomycosis]

This article presents the case of a 44-year-old contact lens wearer who presented with acute keratitis resistant to antibacterial treatment in the right eye. The anterior segment of the eye showed circular conjunctival hyperemia, a corneal white cell infiltrate with radiating margins and a central corneal erosion. Microbiological investigation of a corneal scraping revealed growth of Scedosporium apiospermum. Intensive antimycotic treatment and several corneal collagen crosslinking procedures were performed; however, because of rapidly evolving necrotizing ulcerative keratitis, a keratoplasty à chaud was carried out.

Causative fungi and treatment outcome of dematiaceous fungal keratitis in North India

Purpose

The aim of the study is to identify risk factors, clinical characteristics, causative fungi, and treatment outcome of dematiaceous fungal keratitis in North India.

Methods

Consecutive cases of culture-proven dematiaceous fungal keratitis between January 2012 and June 2017 were retrieved from the medical record department. Risk factors, clinical signs, and outcome were registered.

Results

Eighty-three patients were included. Identified dematiaceous fungal organism were Curvularia sp. (n = 55/83; 66.3%), Alternaria sp. (n = 12/83; 14.5%), Ulocladium sp. (n = 5/83; 6%), Bipolaris sp. (n = 5/83; 6.1%), Scedosporium sp. (n = 3/83; 3.6%), Acremonium sp. (n = 2/83; 2.4%), and Epicoccum sp. (n = 1/83; 1.2%). Male preponderance was reported. The most common predisposing factor was corneal trauma (67.4%). In cases associated with corneal trauma due to vegetative matter, sugarcane was the most common cause. In all, 89% of the patients were more than 30 years of age. The median infiltrate size was 8 mm². The median time of antifungal therapy was 4.2 weeks (interquartile range [IQR]: 1-25 weeks). Complications were seen in 14 (n = 14/65; 21.5%) patients. Complete resolution of dematiaceous fungal keratitis was present in 27 (n = 27/65; 41.5%) eyes.

Conclusion

Curvularia sp. and Alternaria sp. were the predominant pathogenic genera causing dematiaceous fungal keratitis. Among the causative fungi, infections due to Scedosporium sp. were associated with the worst outcomes. Ulocladium sp. and Epicoccum sp. were also identified. Both the species are not reported previously as a causal organism of dematiaceous fungal keratitis from North India.

A case report of infectious scleritis with corneal ulcer caused by Scedosporium aurantiacum

RATIONALE

Scedosporium species is rare pathogen of ocular infection. The accurate diagnosis is delaying in many cases and the clinical prognosis is poor due to its resistance to antifungal agents. This report describes a patient with infectious scleritis and corneal ulcer caused by Scedosporium auranticum infection who required enucleation to control the infection.

PATIENT CONCERNS

A 70-year-old woman visited our clinic after experiencing ocular discomfort in her right eye for 4 days after minor ocular trauma, with soil exposure.

DIAGNOSES

Scedosporium species was isolated from a culture of corneal tissue, Scedosporium aurantiacum was identified in a culture of necrotic tissue.

INTERVENTIONS

She was started on treatment with antifungal agents, including topical amphotericin B and systemic fluconazole, but her ocular condition did not improve. Although the lesion showed temporary improvement, ocular pain and corneal ulcer recurred 3 months later. Evisceration was performed due to corneal perforation, and enucleation was also performed for dehiscence of the conjunctiva and scleral necrosis.

OUTCOMES

After enucleation, postoperative systemic voriconazole treatment controlled the infection without recurrence.

LESSONS

S aurantiacum keratitis is difficult to eradicate, even with several months of treatment with systemic and topical antifungal agents, and tends to progress to scleritis. The infection can be terminated by the orbital enucleation. Infection with this rare organism should be included in the differential diagnosis of patients with severe infectious keratitis.

Mycotic keratitis caused by Scedosporium apiospermum in an immunocompetent patient

CLINICAL CASE

A 51 year-old immunocompetent male was referred due to presenting with a large corneal ulcer with hypopyon in the right eye. Topical amphotericin B, fluconazole and moxifloxacin, as well as oral itraconazole were initially indicated. Following the report of mycotic structures on staining, topical natamycin was started. The result of the culture was reported two weeks later as, Scedosporium apiospermum (S. apiospermum), and topical voriconazole was then added. The response to treatment was very slow, and took five weeks after receiving triple therapy (natamycin, voriconazole and fluconazole) and one dose of intrastromal voriconazole, for the hypopyon to disappear. The final outcome was successful, achieving healing of the ulcer. The patient is waiting for a corneal transplant.

DISCUSSION

A microbiological study is essential in patients in whom fungal keratitis is suspected. The treatment of choice against S. apiospermum is with voriconazole, but the combination of various antifungal agents may be required.

Ocular infections caused by Scedosporium apiospermum: A case series

The aim of our retrospective study is to report a case series of ocular infections caused by a rare fungus, Scedosporium apiospermum, in a South Indian population. Thirteen cases of culture-positive S. apiospermum infections diagnosed between January 2011 and March 2016 were included in this study. The parameters evaluated were predisposing factors, treatment and final clinical outcome. The most common mode of presentation was keratitis (84.6%) followed by sclerokeratitis (15.3%). The predisposing factors involved were unspecified foreign body injury (30.7%), organic matter injury (15.3%), uncontrolled diabetes (7.6%), and recent manual small-incision cataract surgery (7.6%). Five cases (38.46%) had no predisposing factor. Of the 11 keratitis cases, nine (69.2%) responded well to combination medical therapy while one case (7.6%) required therapeutic keratoplasty. One case was lost to follow-up. Both cases which presented with sclerokeratitis showed no response to medico-surgical treatment progressing to panophthalmitis and evisceration.