Rhinofacial conidiobolomycosis: Clinical and microbiological characterisation and shift in the management of a rare disease.

BACKGROUND: Conidiobolomycosis is a rare tropical rhinofacial fungal infection which has not been well characterised. The available evidence in its management is sparse due to lack of clinical studies and the limited data on antifungal susceptibility patterns. OBJECTIVE: To analyse the clinical manifestations, antifungal treatment and outcomes of patients with conidiobolomycosis and to determine antifungal susceptibility profiles of the isolates. PATIENTS/METHODS: Retrospective analysis of data of all patients with a diagnosis of conidiobolomycosis confirmed by histopathology and culture at a tertiary care hospital from 2012 to 2019 was done. RESULTS: There were 22 patients, 21 males and one female, with a mean age of 37.1 years. Most common presenting symptom was nasal obstruction, found in 20 (90.90%) patients. Patients who presented within 12 months had a better cure rate (85%) compared to those who presented late (67%). Among the 19 patients who had a follow-up, good outcome was seen in 15 of the 17 (88.24%) patients who were on itraconazole or potassium iodide containing regimen. Of the six patients who received additional trimethoprim-sulphamethoxazole (co-trimoxazole), 67% showed good outcome with two patients showing complete cure and two patients still on treatment with significant improvement. High minimum inhibitory concentration (MIC) values were noted for azoles and amphotericin B, whereas co-trimoxazole showed lowest MIC ranges. CONCLUSION: Itraconazole and potassium iodide are reasonable first-line options for the treatment of conidiobolomycosis. Good clinical response to KI and comparatively lower MIC of co-trimoxazole are promising. Further studies are required for developing clinical breakpoints that can predict therapeutic outcomes.

A first-line antiretroviral therapy-resistant HIV patient with rhinoentomophthoromycosis.

The Conidiobolus coronatus-related rhinoentomophthoromycosis in immunocompetent and immunocompromised (HIV negative) individuals has been treated successfully with antifungal drugs. However, C. coronatus infections in first-line antiretroviral therapy (ART)-resistant (HIV infected) individuals particularly with rhinoentomophthoromycosis have not been reported previously. Here, we describe a case of itraconazole non-responding rhinoentomophthoromycosis in an HIV-infected patient with first-line antiretroviral (ART) drug resistance which was successfully managed through systematic diagnostic and therapeutic approaches in dermatologic setting. A 32-year-old HIV-1-infected man presented with painless swelling, nasal redness and respiratory difficulty. The patient was receiving first-line ART and had a history of traumatic injury before the onset of nasopharyngeal manifestations. The patient's previous history included oral candidiasis and pulmonary tuberculosis.

Pathogenicity of Conidiobolus coronatus and Fusarium solani in mouse models.

To study the pathogenicity of Conidiobolus coronatus (C. coronatus) and Fusarium solani (F. solani) in animal models. Immunocompromised mice were treated with cyclophosphamide and prednisolone via intraperitoneal injection before and after inoculation. According to pathogenic characteristics of different fungi, C. coronatus was used to infect mice via intravenous inoculation, intraperitoneal inoculation, gastrointestinal infusion and intradermal inoculation methods. And F. solani was used to infect mice by inoculation via the abraded or normal skin. In the group of immunocompromised mice, C. coronatus was isolated from the lung tissues of one mouse on day 7 and another on day 10 respectively. The corresponding histopathology revealed infiltration of local inflammatory cells in the lung tissue. Pathogenic lesions were observed in all normal and immunocompromised mice infected with F. solani via abraded skin. The lesions in the immunocompromised mice were more severe and persisted longer than those in the normal mice. Moreover, hyphae were mostly observed in the histopathological examination and fungal culture from the immunocompromised mouse. The pathogenicity of C. coronatus was relatively weak as it did not induce local infections and did not disseminate the disease in immunocompetent and immunocompromised mice. Therefore, F. solani is a type of opportunistic pathogenic fungus, and abraded skin is one of the causative routes of infection.

Orofacial infection by Conidiobolus coronatus.

Entomophtoramycosis is a type of subcutaneous mycosis which includes both basidiobolomycosis and conidiobolomycosis; the latter is caused by Conidiobolus coronatus, a saprophytic fungus which lives in tropical soils. This mycosis characteristically affects the paranasal sinuses and oropharynx, with the potential to deform the face in patients without apparent immunodeficiency. It has a chronic course of infection with a tendency to form granulomas visible using histology. We present the case of a 28 year-old male agricultural worker, with a clinical profile of 6 months' evolution of rhinofacial tumefaction, nasal obstruction and post-nasal drip who was diagnosed with conidiobolomycosis by means of tissue culture after multiple biopsies of the facial area. The patient received antifungal treatment with amphotericin B and subsequently with itraconazol, resulting in a dramatic improvement without the need for surgical treatment; itraconazol was administered for one year and there was no evidence of relapse at the end of this period. Due to the low frequency of this disease there is no established treatment strategy; however, the use of azoles such as itraconazol with or without adjuvant surgical treatment is increasingly seen in case reports. The present report adds to the clinical experience in Colombia of this rare mycosis and also describes the long-term clinical and therapeutic response.

In vitro susceptibility of Conidiobolus lamprauges recovered from sheep to antifungal agents.

Data regarding the susceptibility of Conidiobolus lamprauges is limited and there is no consensus about the optimal treatment for infections caused by Conidiobolus spp. In this context, the objective of this study was to evaluate the in vitro susceptibility of six C. lamprauges strains isolated from sheep conidiobolomycosis to amphotericin B, ketoconazole, fluconazole, itraconazole, posaconazole, voriconazole, anidulafungin, caspofungin, micafungin, flucytosine, and terbinafine using the CLSI M38-A2 microdilution technique. Terbinafine was the most active (MIC range <0.06-0.5 µg/mL). Resistance or reduced susceptibility was observed for amphotericin B and azole and echinocandin antifungals. Additional studies are necessary to determine the therapeutic potential of terbinafine as monotherapy or in combination therapy with other antifungals.

Free fatty acids in the cuticular and internal lipids of Calliphora vomitoria and their antimicrobial activity.

The cuticular and internal lipid composition in Calliphora vomitoria larvae, pupae, and male and female adults was studied. The free fatty acid (FA) compositions of the lipids were chemically characterized using gas chromatography (GC) and gas chromatography-electron impact mass spectrometry (GC-MS). Analyses of cuticular extracts from larvae, pupae, and male and female adults revealed that the carbon numbers of the acids ranged from C7:0 to C22:0, from C8:0 to C24:0, from C7:0 to C24:0 and from C7:0 to C22:0 respectively. The internal lipids of C. vomitoria larvae, pupae, male and female adults contained FAs ranging from C8:0 to C20:0, from C9:0 to C22:0, from C8:0 to C24:0 and from C9:0 to C22:0 respectively. Nine FAs with odd-numbered carbon chains from C7:0 to C21:0 were identified in the cuticular lipids of the larvae. The internal lipids of C. vomitoria larvae contained 8 odd-numbered FAs ranging from C9:0 to C19:0. Eight odd-numbered FAs from C9:0 to C21:0 were identified in the cuticular and internal lipids of pupae, while nine such FAs were found in the cuticular lipids of male and female adults. The internal lipids of adult males and females respectively contained nine and seven odd-numbered FAs, while both larvae and pupae contained eight such compounds. Eight unsaturated FAs were identified in the cuticular lipids of larvae, adult males and females and also in the internal lipids of females. Seven unsaturated FAs were identified in the cuticular lipids of pupae. The internal lipids of larvae, pupae and males contained 10, 11 and 12 unsaturated FAs respectively. Developmental changes were found both in the amounts of extracted cuticular and internal FAs and in their profiles. Four cuticular FAs (C7:0, C9:0, C10:0 and C15:1), identified as being male-specific, were either absent in the female cuticle or present there only in trace amounts. Cuticular and internal extracts obtained from larvae, pupae, adult males and females were tested for their potential antimicrobial activity. The minimal inhibitory concentrations of extracts against reference strains of bacteria and fungi were determined. Antimicrobial activity was the strongest against Gram-positive bacteria; Gram-negative bacteria, on the other hand, turned out to be resistant to all the lipids tested. Overall, the activities of the internal lipids were stronger. All the lipid extracts were equally effective against all the fungal strains examined. In contrast, crude extracts containing both cuticular and internal lipids displayed no antifungal activity against the entomopathogenic fungus Conidiobolus coronatus, which efficiently killed adult flies, but not larvae or pupae.

Effects of insect cuticular fatty acids on in vitro growth and pathogenicity of the entomopathogenic fungus Conidiobolus coronatus.

Eighteen fatty acids identified in the cuticle of three insect species representing differing susceptibilities to C. coronatus infection, were tested for effects on the in vitro growth and pathogenicity of the parasitic fungus. At all applied concentrations (0.1-0.0001% w/v) growth was inhibited by C(16:0), C(16:1), C(18:0), C(18:1), C(18:2), C(18:3), C(20:0) and C(20:1). At high concentrations spore germination was inhibited by C(7:0), C(8:0), C(9:0), C(10:0), C(12:0), C(18:2) and C(18:3) and hyphal growth was merely retarded by C(5:0), C(6:0), C(6:2), C(14:0), C(16:0), C(16:1), C(18:0,) C(18:1), C(20:0) and C(20:1). The presence of C(15:0) at the 0.1% concentration stimulated growth of C. coronatus. Sporulation was inhibited by all concentrations of C(16:0) and C(18-20) fatty acids. Low concentrations of C(5:0), C(6:0), C(6:2) and C(7:0) enhanced sporulation. Fatty acids C(5-12) as well as C(18:3), C(20:0) and C(20:1) decreased the ability of fungal colonies to infect G. mellonella while C(16:1) elevated it thus suggesting that C(16:1) may stimulate production of enzymes involved in the host invasion. Toxicity of metabolites released into incubation medium decreased with varying degrees in the presence of C(6:0), C(6:2,) C(7:0), C(9:0), C(12:0), C(16:1), C(18:2), C(18:3), C(20:0) and C(20:1); other fatty acids had no effect. Further work is needed to analyse the effects of exogenous fatty acids on the C. coronatus enzymes implicated in fungal pathogenicity as well as on the production of insecticidal metabolites.

Rhinofacial Conidiobolus coronatus infection presenting with nasal enlargement.

Rhinofacial Conidiobolus coronatus infection is a rare form of zygomycosis in humans living in the northern hemispheres. Most human cases are observed in the periequatorial areas of Africa, Asia, or South America. Only limited information regarding optimal treatment is available. We report a case of rhinofacial C. coronatus infection in an emigrated Sudanese patient. The infection was successfully treated with terbinafin and itraconazole for 12 months. Diagnosis was confirmed by microbiological culture from a tissue biopsy. Antimicrobial susceptibility testing of this organism was not predictive of optimal therapy.

Nasofacial phycomycosis: persistence pays.

Nasofacial phycomycosis caused by Conidiobolus is a rare fungal infection most often encountered in the developing world in conditions of poverty. A clinical presentation of the natural history of this condition observed over a period of 6 years by a visiting volunteer surgical team demonstrates the role of multimodality surgical and antifungal drug treatment in producing a successful outcome. The particular sensitivity of this infection to the new generation antifungal Voriconazole is noted.

Novel bifunctional alkaline protease inhibitor: protease inhibitory activity as the biochemical basis of antifungal activity.

An alkaline protease inhibitor (API) from a Streptomyces sp. NCIM 5127 was shown to possess antifungal activity against several phytopathogenic fungi besides its antiproteolytic (anti-feedent) activity [J. V. Vernekar et al. (1999) Biochem. Biophys. Res. Commun. 262, 702-707]. Based on the correlation between antiproteolytic and antifungal activities in several tests such as copurification, heat inactivation, chemical modification, and its binding interaction with the fungal protease, we demonstrate, for the first time, that the dual function of API is a consequence of its ability to inhibit the essential alkaline protease. The parallel enrichment of both the functions during purification together with the heat inactivation of API leading to the concomitant loss of the two activities suggested their presence on a single molecule. Chemical modification of API with NBS resulted in the complete loss of antiproteolytic and antifungal activities, with no gross change in conformation implying the involvement of a Trp residue in the active site of the inhibitor and the presence of a single active site for the two activities. Treatment of API with DTT abolished both the activities although the native structure of API remained virtually unaffected, indicating the catalytic role of the disulfide bonds. Inactivation of API either by active site modification or by conformational changes leads to the concurrent loss of both the antiproteolytic and antifungal activities. Experimental evidences presented here serve to implicate that the antifungal activity of API is a consequence of its protease inhibitory activity.

[Influence of free fatty acids on growth, sporulation and virulence of the parasitic fungus Conidiobolus coronatus]. / Wplyw wolnych kwasów tluszczowych na wzrost, sporulacje i wirulencje pasozytniczego grzyba Conidiobolus coronatus.

Five free fatty acids (FFA): C16:0, C18:0, C18:1, C18:2 and C18:3 were introduced into culture media in order to investigate differential development of pathogenic fungus Conidiobolus coronatus as a function of FFA concentration. All tested FFA showed fungistatic action inhibiting hyphae growth and sporulation. Fungal colonies grown in the presence of FFA showed decreased virulence.

In-vitro antifungal susceptibilities of Basidiobolus and Conidiobolus spp. strains.

The in-vitro antifungal susceptibilities of nine isolates belonging to Basidiobolus spp. and seven to Conidiobolus spp. against six antifungals (amphotericin B, ketoconazole, miconazole, itraconazole, fluconazole and flucytosine) were tested. A broth microdilution method, generally following the NCCLS guidelines, was used. Inoculum concentrations of the order of 100 cfu/mL were obtained by culturing fungi in a broth medium (Czapeck broth supplemented with 2% Tween 80 and 0.07% agar). MICs and MFCs were highly variable and isolate-dependent, with the exception of those of flucytosine which were constantly very high. In general, however, Basidiobolus spp. displayed low MICs of fluconazole, itraconazole, ketoconazole and miconazole, and Conidiobolus spp. were resistant to all antifungals tested.