A Rare Fungal Orbital Infection in an Immunocompetent Young Male Caused by Lichtheimia corymbifera (Absidia corymbifera).

AIM: To present a case of orbital fungal infection caused by a rare fungus, Lichtheimia corymbifera (Absidia corymbifera) in an immunocompetent individual. MATERIALS AND METHODS: A retrospective case study. RESULT: A 23-year-old male presented with painful proptosis of the right eye for 3 months. Examination revealed normal vision and pupillary light reflex but restricted ocular movements in the right eye. A tender, firm mass was palpable along the inferomedial quadrant of the right orbit. He had acute worsening of proptosis with loss of light perception within 24 hours. Magnetic resonance imaging (MRI) showed a heterogeneously enhancing lesion in the right orbit. Urgent incisional biopsy revealed the growth of Absidial fungal infection. He received intravenous Amphotericin B for 2 weeks with no response. Repeat MRI revealed an extension of the infection up to the cavernous sinus and intracranial optic nerve. He was managed by subtotal exenteration, socket irrigation with Amphotericin B, and intravenous Amphotericin B. CONCLUSION: Invasive orbital fungal infection, though rare, should be considered a differential diagnosis in immunocompetent patients with fulminant proptosis and vision loss.

Cutaneous Absidia corymbifera in a Lupus Nephritis Patient.

A 28-year-old farmer with class IV lupus nephritis presented with a two-week history of a right shin lesion. The lesion was purple in color, fungating, and indurated with a focus of deep ulceration at the inferior pole and punctate, bleeding from its surface. Three months earlier, he was started on induction immunosuppression for a relapse of his lupus nephritis. Since the diagnosis of lupus nephritis, nine years previously, he had had six flares of his disease and had been treated at different time points with cyclophosphamide, rituximab, and high-dose corticosteroids, without adverse events. Laboratory investigations showed improving kidney function (chronic kidney disease [CKD] stage IV) with reducing proteinuria, on his current immunosuppressive regimen. The differential diagnosis for this lesion was calciphylaxis, pyoderma gangrenosum, vasculitic lesion, or an infection. Histology and microbiological analysis confirmed the presence of Absidia corymbifera. He was treated with a combination of isavuconazole, reduction of his immunosuppressive agents, excision of the lesion, and skin grafting.

Invasive Fungal Infection with Absidia Corymbifera in Immunocompetent Patient with Electrical Scalp Burn.

Invasive fungal infection in burn injury is caused by inoculation of fungal spore from patient skin, respiratory tract or from care giver. The risk factors for acquiring fungal infection in burns include age of burns, total burn size, full thickness burns, inhalational injury, prolonged hospital stay, late surgical excision, open dressing, central venous catheters, antibiotics, steroid treatment, long-term artificial ventilation, fungal wound colonization, hyperglycemic episodes and other immunosuppressive disorders. Invasive fungal infection with Absidia corymbifera is rare opportunistic infection encountered in patient with burn injury. The key for treatment is early clinical diagnosis, wide and repeated debridement and systemic and local antifungal treatment. We describe a case of invasive fungal infection with A. corymbifera in a patient with post-electrical scalp burn with late presentation after 10 days of injury in an immunocompetent patient.

Keratitis caused by Absidia corymbifera in an immunocompetent male with no corneal injuries.

Case Report A healthy 55-years-old male went to emergency due to a white infiltrate in the left eye without corneal trauma which partially responds to antibiotic treatment. The infiltrate worsened by the use of topical steroids. Direct microscopic evaluation and Gram stain are a valuable diagnostic tool for the detection of Absidia filaments. There is a successful treatment with anphotericin and posaconazole. Discussion Keratitis caused by Zygomicetes are unusual. This is a rare condition in healthy patients with no corneal trauma. The treatment with amphotericin and posaconazole are synergistic against filamentous fungi.

Glycoprotein secreted by Absidia corymbifera is associated with apoptosis of human umbilical vein endothelial cells / 中华微生物学和免疫学杂志

Objective To partially purify the toxic factor secreted by A. corymbifera and to analyze the mechanism of A. corymbifera-induced human umbilical vein endothelial cell (HUVEC) apoptosis. Methods Glycoprotein secreted by A. corymbifera was purified by Con A Lectin chromatography. The influence of different protein fractions on HUVEC apoptosis was determined by flow eytometer. Both denaturing and nondenaturing deglycosylation of purified glycoprotein was performed and the ability of the protein moiety and carbohydrate moiety to induce HUVEC apoptosis was evaluated respectively. Activation of related caspases during A. corymbifera-induced apoptosis was analyzed by Western blot. The role of caspase-8 and -9 in HUVEC apoptosis was investigated using caspase inhibitors. Caspase inhibitors were used to stop the suppression of HUVEC viability by XTT assay. Results Flow cytometric analysis shows the total protein as well as the glycoprotein fraction of A. corymbifera may induce HUVEC apoptosis in a dose dependent manner. In contrast, similar activity was not observed in the non-glycoprotein fraction. Neither deglycosylated protein nor carbohydrate moiety is able to induce HUVEC apoptosis alone. In the apoptotic signaling pathway, caspase9, caspase-3 and cytochrome C were activated significantly, except caspase-8. Moreover, caspase-9 inhibitor, instead of caspase-8 inhibitor, completely abrogates A. corymbifera-induced HUVEC apoptosis. Caspase9 and caspase-3 inhibitors completely waived the suppression of HUVEC viability by A. corymbifera. Conclusion Glycoprotein secreted by A. corymbifera is associated with HUVEC apoptosis. Intact glycoprotein is essential for the apoptotic progress. Intrinsic apoptotic signaling pathway mediates A. corymbifera-induced HUVEC apoptosis.

Absidia corymbifera induces apoptosis of human umbilical vein endothelial cells in vitro / 中华微生物学和免疫学杂志

Objective To analyze the influence of Absidia corymbifera on cell activity of human umbilical vein endothelial cells (HUVEC) as well as the related mechanism. Methods Time course analy sis of the influence of A. corymbifera on cell viability of HUVEC was determined by cell counting after Trypan blue staining. Apoptosis of HUVEC induced by A. corymbifera was observed under fluorescence microscope after treatment with apoptosis detection kit. Time course analysis of HUVEC apoptosis induced by A. corymbifera was detected by flow cytometry quantitatively. Effect of caspase-3 inhibitor on A. corymbifera associated apoptosis was also evaluated at the same time. Activation of caspase-3 inside HUVEC was detected by Western blot. Results A. corymbifera inhibited cell viability of HUVEC in a time-dependent manner by Trypan blue staining. After 12 hours' co-culture, A. corymbifera began to show suppression on cell viability (P =0. 001 ). Fluorescence microscope observation revealed A. corymbifera induced apoptosis of HUVEC instead of necrosis. Flow cytometry analysis showed A. corymbifera induced apoptosis of HUVEC in a time-dependent manner. A. corymbifera began to show obvious effect on apoptosis after 12 h co-culture (P =0.0036). Moreover, A. corymbifera-associated apoptosis was almost abrogated completely by caspase-3 inhibitor. Western blot analysis demonstrated that A. corymbifera triggered the activation of caspase-3 inside HUVEC in a timedependent fashion. Conclusion A. corymbifera induces apoptosis of HUVEC in vitro. Such apoptotic signal is transmitted through caspase cascade reaction.

Cutaneous mucormycosis caused by Absidia corymbifera in a horse.

A 5-year-old pregnant Spanish thoroughbred mare was presented with an extensive granulomatous lesion, of four months duration, on the left medial foreleg. On examination, the wound was covered by a large mass of ulcerated granulation tissue exuding thick serosanguinous fluid. The mare had not responded to previous treatment. Physical examination revealed no fever, no lameness and the presence of intense pruritus. A surgical resection was carried out to take samples for histopathology. On histopathologic examination the dermis and subcutaneous tissue showed large multifocal necrotic eosinophilic areas and inside these areas, irregularly ramified fungal hyphae. Microbiological examination showed abundant fungal growth and the strain corresponded to Absidia corymbifera. Treatment with amphotericin B was started but there was no improvement in the lesion. The mare aborted, became anorexic, had febrile episodes, had very poor body condition and was euthanized.