Ocular Basidiobolomycosis: A Case Report

Abstract

Background: Ocular basidiobolomycosis is an unusual infection caused by fungus of the order Entomophthorales. This fungus has been previously reported as a common cause of skin, subcutaneous, and gastrointestinal tract infection. The fungus isolation and its typical characteristics are clues for diagnosis of this uncommon pathogen. Case Report: A 47-year-old male patient with nodular scleritis in the left eye after an eye injury from sawdust was treated as bacterial scleritis. The lesion improved with early surgical drainage and antibacterial therapy; then, he was discharged from the hospital. Thereafter, the patient was re-admitted due to progression of infectious scleritis with keratitis and orbital cellulitis. Surgical abscess drainage was performed again. The microbiological study demonstrated Basidiobolus ranarum. The patient was treated with topical ketoconazole, subconjunctival fluconazole injection, and oral itraconazole with partial response to the treatment. However, the patient eventually denied any further treatment and did not return for follow-up. Conclusions: B. ranarum is a rare pathogen of ocular infection in which a definite diagnosis requires isolation of the causative organism. Delay in diagnosis and appropriate treatment can lead to extension of the infection and poor outcomes.

Divergent Evolution of Early Terrestrial Fungi Reveals the Evolution of Mucormycosis Pathogenicity Factors

“…The “mycobacterial membrane protein large transporter” domain is well represented in all three subphyla of Mucoromycota as well as Basidiobolus ( fig. 2 e ) consistent with the observations of fungal–bacterial interactions documented in these lineages ( Uehling et al 2017 ; Desirò et al 2018 ; Chang et al 2019 ; Bonfante and Venice 2020 ; Tabima et al 2020 ). Although the TLD domain is universally present in almost all fungal lineages (except Wallemia ichthyophaga ), the exceptionally large number of TLD domains identified in Glomeromycotina members is unusual ( fig.…”

“…S1, Supplementary Material online). The complex mixed history observed in the genomes of Basidiobolus is evidenced by their enriched secondary metabolite genes many of which are result of horizontal gene transfer from Bacteria, regionally duplicated genomes, and the broad range of animal hosts it can be found to inhabit including insects, amphibians, reptiles, and human beings ( Henk and Fisher 2012 ; Tabima et al 2020 ). This may explain the sources of phylogenetic conundrums that we have encountered in the last decades using different molecular markers.…”

“…Progress on genomics and related multi-omics has greatly expanded our knowledge on zygomycetes. This includes the identification of a mosquito-like polyubiquitin gene in a zygomycete fungus inhabiting the gut of mosquitoes ( Zancudomyces culisetae , Zoopagomycota) ( Wang et al 2016 ), the discovery of a photosynthetic mycelium using algal symbionts ( Linnemannia elongata , Mortierellomycotina) ( Du et al 2019 ; Vandepol et al 2020 ), the isolation of cicada behavior modifying alkaloids from Massospora (Entomophthoromycotina) ( Boyce et al 2019 ), and the expansion of secondary metabolite genes of amphibian gut fungi ( Basidiobolus , Entomophthoromycotina) via Horizontal Gene Transfer from bacteria co-existing in the gastrointestinal tract ( Tabima et al 2020 ). However, a conundrum remains as to the evolutionary history of the zygomycete fungi.…”

Infectious Scleritis: Pathophysiology, Diagnosis, and Management

“…2,5,11 Several reports have described atypical cases featuring a painfree presentation, normal visual acuity, lack of corneal infiltrates, normal intraocular pressure, and absence of anterior chamber reaction. 8,[45][46][47][48] Other uncommon manifestations include aqueous fistula formation in pneumococcal scleritis, inverse hypopyon in a case of pyomyositis with S. aureus scleritis, and spontaneous IS in immunocompromised patients with no history of ocular surgery or trauma. 5,32,49 Infectious scleritis may also masquerade as other diseases, including SINS, autoimmune scleritis, ocular tumors, orbital cellulitis, cavernous sinus thrombosis, and carotidcavernous fistula.…”

Divergent evolution of early terrestrial fungi reveals the evolution of Mucormycosis pathogenicity factors

“…Basidiobolus can be isolated from various types of environments, including soils or leaf litters, dung of frogs or lizards, and various insects (e.g., mosquitoes, mites, springtails) (Lyon et al 2001; Garros et al 2008; Manning and Callaghan 2008; Werner et al 2012). Recently, people also found that Basidiobolus can infect human eyes (Tananuvat et al 2018; Vilela and Mendoza 2018). The two CotH copies identified in Basidiobolus genomes may be involved in the pathogenic processes.…”