Indian Journal of Pathology and Microbiology

LETTER TO EDITOR
Year
: 2010  |  Volume : 53  |  Issue : 3  |  Page : 587--588

Post traumatic fungal keratitis caused by Acremonium recifei


Susan Verghese 
 Department of Microbiology, Chettinad Hospital and Research Institute, Kelambakkam, Kancheepuram Dist., Chennai - 603 103, Tamil Nadu, India

Correspondence Address:
Susan Verghese
Department of Microbiology, Chettinad Hospital and Research Institute, Kelambakkam, Kancheepuram Dist., Chennai - 603 103, Tamil Nadu
India




How to cite this article:
Verghese S. Post traumatic fungal keratitis caused by Acremonium recifei.Indian J Pathol Microbiol 2010;53:587-588


How to cite this URL:
Verghese S. Post traumatic fungal keratitis caused by Acremonium recifei. Indian J Pathol Microbiol [serial online] 2010 [cited 2021 Sep 23 ];53:587-588
Available from: https://www.ijpmonline.org/text.asp?2010/53/3/587/68263


Full Text

Sir,

Fungal keratitis is a common, potentially sight-threatening ocular infection. The majority of cases occur after corneal injury, usually by fungus-contaminated plant material. A broad spectrum of fungal species have been identified as etiologic agents. [1]

Our patient was a 33-year-old male who had a history of injury to the left eye, which failed to heal. Local therapy with antibiotics did not resolve the problem for more than 2 weeks.

On examination, the eye had mild redness and there was a centrally placed corneal ulcer that had infiltrating edges. He complained of pain, lacrimation and redness of the eye. He underwent a corneal scraping procedure in the operation theater and the material was plated on multiple media such as blood agar, MacConkey agar and Sabauraud's dextrose agar, which were incubated at two temperatures (37 o C and 22 o C) and thioglycolate broth.

The KOH mouth revealed fungal septate hyphae. The Gram's smear also showed partially stained fungal filaments. The patient was started on natamycin 5% eye drops, which were used six times a day. He was lost to follow-up as he did not come back for a review. The culture yielded a moderately rapidly growing fungus that was at first white but soon changed to pink, with the reverse also pink to brown, and it produced a brown diffusing pigment into the medium [Figure 1].

The lactophenol blue mount revealed awl-shaped phialides that tapered and that held groups of crecentric conidia which were nonseptate. The conidia appeared bound by gelatinous material [Figure 2].

Susceptibility test for the fungus was not performed because it was unavailable and the response to treatment could not be assessed as the patient was lost to follow-up.

Acremonium spp. are filamentous fungi commonly isolated from plant debris and soil. They are classified among the deuteromycetes group of fungi by some authorities.

There are three main species of Acremonium commonly \implicated in infections are : Acremonium falciforme, Acremonium kiliense and Acremonium recifei.[2]

Acremonium species are one of the causative agents of eumycotic white grain mycetoma. It has been implicated in rare cases of onychomycosis, keratitis, endophthalmitis, endocarditis, meningitis, peritonitis and osteomyelitis. [2] This fungus is known to cause opportunistic infections in immunocompromised patients, such as bone marrow transplant recipients.

Because Acremonium species are cosmopolitan in nature, they can also be encountered as contaminants. Thus, their isolation in culture requires cautious evaluation.

Chander et al.[3] have reported that Aspergillus species were the most common agents causing fungal keratitis, in their study form North India. Acremonium species formed only 6.6% of their total number of isolates. Saha et al.[4] have also reported that Aspergillus species were the most common agents causing corneal ulcers from East Delhi. In contrast, in a report from Chennai, South India, Fusarium species were the most frequent fungi isolated, forming 45.85% of the isolates, followed by Aspergillus species, which formed 24.37% of the isolates. [5]

The phialides of Acremonium are separated from the hyphae by a septum and taper toward their apices. At the apices of the phialides are hyaline conidia 2 to 3 Χ 4 to 8 ΅m in size. They usually appear in clusters, in balls or, rarely, as fragile chains. The conidia are bound by a gelatinous material. They may be single or multicellular, fusiform with a slight curve or resemble a shallow crescent. These structural properties of the conidia vary depending on the species.

Acremonium falciforme usually produces crescentic, nonseptate conidia. Sometimes, two- or three-celled conidia may also be observed. Acremonium kiliense, on the other hand, has a short straight conidia and the conidia of Acremonium recifei are usually crescentic and nonseptate. This isolate was identified as Acremonium recifei because of the cresentric nonseptate conidia and the presence of brown diffusing pigment in the medium.

The risk factors for fungal keratitis are agricultural occupation, male gender, age between 30 and 59 years, history of trauma and self-medication. The response to treatment in fungal keratitis depends both on antifungal therapy and on surgical intervention when the ulcers are large. Newer agents, such as Voriconazole and Posaconazole, exhibit favorable in vitro activity against Acremonium species. Itraconazole has high MICs for Acremonium isolates. Natamycin, also known as Pimaricin, is a naturally occurring antifungal agent produced during fermentation by the bacterium Streptomyces natalensis, commonly found in soil. Natamycin is classified as a macrolide polyene antifungal and is recommended for the treatment of fungal keratitis.

To conclude, it is important to correctly identify the causative agent of keratitis in order to treat the patient effectively.

References

1Horstkotte MA, Horstkotte MA, Weiίmann J, Engelmann K, Gantier JC, Sobottka I. Successful treatment of ulcerating keratitis due to Acremonium recifei with Voriconazole. 15 th European Congress of Clinical Microbiology and Infectious Diseases; 2005. p. 1134_01_345 Abs.
2Fincher RM, Fisher JF, Lovell RD, Newman CL, Espinel-Ingroff A, Shadomy HJ. Infection due to the fungus Acremonium (cephalosporium). Medicine (Baltimore) 1991;70:398-409.
3Chander J, Sharma A. Prevalence of fungal corneal ulcers in northern India. Infection 1994;22:207-9.
4Saha R, Das S. Mycological profile of infectious Keratitis from Delhi. Indian J Med Res 2006;123:159-64.
5Bharathi MJ, Ramakrishnan R, Vasu S, Meenakshi, Palaniappan R. Aetiological diagnosis of microbial keratitis in South India - A study of 1618 cases. Indian J Med Microbiol 2002;20:19-24.