Antifungal Effect and Inhibition of the Virulence Mechanism of D-Limonene against Candida parapsilosis

Yeasts from the Candida parapsilosis complex are clinically relevant due to their high virulence and pathogenicity potential, such as adherence to epithelial cells and emission of filamentous structures, as well as their low susceptibility to antifungals. D-limonene, a natural compound, emerges as a promising alternative with previously described antibacterial, antiparasitic, and antifungal activity; however, its mechanisms of action and antivirulence activity against C. parapsilosis complex species have not been elucidated. Therefore, in the present study, we aimed to evaluate the antifungal and antivirulence action, as well as the mechanism of action of D-limonene against isolates from this complex. D-limonene exhibited relevant antifungal activity against C. parapsilosis complex yeasts, as well as excellent antivirulence activity by inhibiting yeast morphogenesis and adherence to the human epithelium. Furthermore, the apoptotic mechanism induced by this compound, which is not induced by oxidative stress, represents an important target for the development of new antifungal drugs.

Successful Treatment of Scedosporium Sinusitis in Two Lung Transplant Recipients: Review of the Literature and Recommendations for Management

Background

Scedosporium fungal infection is an emerging disease which is difficult to diagnose and treat. Patients undergoing lung transplant may be colonized prior to transplantation and are at risk for lethal allograft infection after transplantation.

Objectives

To identify and evaluate treatment options.

Methods

This study is a retrospective review of patients treated at a tertiary academic medical center from 2007 to 2017 with positive sinonasal cultures. A review of the literature was also performed to identify additional cases.

Results

Two lung transplant patients had a positive culture for Scedosporium. The literature search resulted in 37 citations, which yielded only 2 prior cases of Scedosporium paranasal sinus colonization or infection in lung transplant recipients. Three of the 4 patients had cystic fibrosis. Two of the patients were colonized before initial transplant, while 1 patient was colonized before subsequent transplant. Three of the 4 patients survived, and all 3 had disease isolated to their sinuses and lungs treated with sinus surgery, while the fourth had disseminated disease and did not undergo sinus surgery. All patients were treated with multiple antifungals due to resistance patterns. One surviving patient cleared both sinus and lung cultures in less than 1 month, while the other 2 surviving patients achieved negative cultures after a minimum of 6 months.

Conclusions

Surgery may be especially important in patients with fungal sinus colonization or infection before or after lung transplantation. Chronic sinusitis is an important source for persistent fungal colonization and reinfection of the allograft which could be removed with surgical debridement before causing highly morbid pulmonary disease.

Successful prevention of scedosporiosis after lung transplantation in a cystic fibrosis patient by combined local and systemic triazole therapy

A persistent colonization with Scedosporium apiospermum (S. apiospermum) often results in disseminated infection with a high mortality rate in immunosuppressed patients. We present the first case of successful prevention of scedosporiosis in an adolescent female cystic fibrosis patient post double lung transplant, with a combination of local and systemic voriconazole therapy and surgical intervention.

Pseudallescheria boydii species complex fungal rhinitis and sinusitis in a dog

A 9 yr old male castrated Australian shepherd mixed-breed dog with a 3 mo history of intermittent unilateral epistaxis was diagnosed with Pseudallescheria boydii species complex fungal rhinitis and sinusitis. This fungal organism is a rare cause of disease in dogs and an emerging human pathogen. The dog was successfully treated with topical clotrimazole.

Orbital and cranial nerve presentations and sequelae are hallmarks of invasive fungal sinusitis caused by Mucor in contrast to Aspergillus

BACKGROUND

Acute fulminant invasive fungal sinusitis (IFS) is a rapidly progressing, destructive process almost exclusively affecting immunocompromised patients. Outcome differences have been found in patients with Mucor and Aspergillus. We performed this study to compare the presenting symptoms and long-term morbidity with IFS caused by Mucor versus Aspergillus species.

METHODS

Retrospective chart review was performed of 48 patients with 49 cases of acute fulminant IFS over a 19-year period. Presenting symptoms and long-term morbidity related to the orbits and cranial nerves were evaluated.

RESULTS

Mucor was found in 22 cases and Aspergillus was found in 27 cases. Orbital (proptosis, periorbital edema, and ophthalmoplegia) and cranial nerve symptoms were seen at presentation more often in Mucor (6 [27%] and 9 [41%]) than in Aspergillus patients (3 [11%] and 7 [26%]; p=0.079). Long-term orbital and cranial nerve sequelae occurred in 16 (72%) Mucor cases and 10 (37%) Aspergillus cases (p=0.0210). The IFS-related mortality was 32% (7) in the Mucor group and 11% (3) in the Aspergillus group (p=0.089).

CONCLUSION

Patients with acute fulminant IFS present with similar sinus symptoms; however, there is a trend toward a greater prevalence of orbital and neurological symptoms in patients with Mucor versus Aspergillus. Long-term orbital and neurological morbidity is more prevalent in patients with Mucor compared with Aspergillus. These data suggest that the presence of orbital and neurological symptoms at presentation warrants more aggressive surgical intervention because of the likelihood of Mucor.

Pseudallescheria fusoidea, a new cause of osteomyelitis

Osteomyelitis resulting from a mold infection often presents as a chronic and indolent disease process. Described here for the first time is a case of osteomyelitis of the foot caused by the mold Pseudallescheria fusoidea, which resulted from traumatic implantation after an injury sustained 3 years earlier.