A Simple and Effective Technique for Production of Pycnidia and Pycnidiospores by Macrophomina phaseolina.

Production of pycnidia and pycnidiospores by Macrophomina phaseolina is not often seen in vitro. The objective of this study is to develop a simple and effective technique to obtain pycnidiospores of M. phaseolina isolates in vitro and to evaluate germination rates and pathogenicity of pycnidiospores. We found M. phaseolina isolates can produce pycnidia on oatmeal agar (OMA) under ultraviolet light with 365 nm wavelength (UV). For evaluating the effect of OMA and UV on growth of M. phaseolina, combinations of two agar media and three lighting conditions were tested. The results confirm that all six M. phaseolina isolates produced pycnidia only on OMA under UV. The pycnidiospores produced on OMA under UV had germination rates higher than 90%. In pathogenicity tests, inoculation with the pycnidiospores showed symptoms later than inoculation with hypha-colonized toothpicks. Significant differences in the pathogenicity is detected between isolates Mp2014003 and Mp2014024 when inoculation is done with the pycnidiospores (P < 0.001), but not when hypha-colonized toothpicks are used as inoculum (P = 0.091). This study provides a new method for obtaining pycnidiospores of M. phaseolina for future investigations.

Phialophora chinensis fungal keratitis: An initial case report and species identification.

Purpose: To report the initial case of microbial keratitis caused by Phialophora chinensis, a rare cause of fungal keratitis. Observations: A 66-year-old gentleman with a complex right eye (OD) ocular history including herpes simplex virus infectious epithelial keratitis with subsequent neurotrophic keratopathy, and prior combined Candida albicans and parapsilosis fungal keratitis presented with pain OD in the absence of an antecedent trauma. The patient was found to have a filamentous fungal keratitis, which was subsequently cultured and identified as Phialophora chinensis by the laboratory. Despite topical and oral antifungal treatment based on sensitivities determined by the lab, the patient ultimately required intrastromal and subconjunctival antifungal injections, corneal crosslinking, and superficial keratectomy with amniotic membrane to clinically improve. The fungal keratitis recurred twice, with each occurrence rapidly progressing to corneal perforation. Months after the second penetrating keratoplasty, the patient's mental status declined due to multiorgan failure. An occult pulmonary malignancy was discovered during this hospital stay, and the patient was lost to follow-up after entering hospice. Conclusions and Importance: We report a unique case of fungal keratitis caused by Phialophora chinensis and the subsequent management, including both medical and surgical interventions. Despite a multimodal treatment regimen, this case demonstrates the recalcitrant and potentially recurrent nature of fungal keratitis caused by P. chinensis.