[Susceptibility of Candida albicans blood isolates to 3 antifungal drugs: retrospective study in Rio Grande do Sul, Brazil, 1999-2009]

Two cases of fungal cyst infection in ADPKD: is this really a rare complication?

Background

Cyst infection is a prevalent complication in autosomal dominant polycystic kidney disease (ADPKD) patients, however therapeutic and diagnostic approaches towards this condition remain unclear. The confirmation of a likely episode of cyst infection by isolating the pathogenic microorganism in a clinical scenario is possible only in the minority of cases. The available antimicrobial treatment guidelines, therefore, might not be appropriate to some patients.

Case presentation

We describe two unique cases of kidney cyst infection by Candida albicans, a condition that has not been previously described in literature. Both cases presented clear risk factors for Candida spp. infection. However, since there was no initial indication of cyst aspiration and culture, antifungal therapy was not immediately started and empirical treatment was initiated as recommended by the current guidelines. Antifungal treatment was instituted in both cases along the clinical course, according to their specificities.

Conclusion

Our report highlights the possibility of Candida spp. cyst infection. Failure of clinical improvement with antibiotics should raise the suspicion of a fungal infection. Identification of infected cysts should be pursued in such cases, particularly with PET-CT, and when technically possible followed by cyst aspiration and culture to guide treatment. Risk factors for this condition, such as Candida spp. colonization, previous antimicrobial therapy, hemodialysis, necrotizing pancreatitis, gastrointestinal/hepatobiliary surgical procedure, central venous catheter, total parenteral nutrition, diabetes mellitus and immunodeficiency (neutropenia < 500 neutrophils/mL, hematologic malignancy, chemotherapy, immunosuppressant drugs), should be also considered accepted criteria for empirical antifungal therapy.

Photodithazine-mediated antimicrobial photodynamic therapy against fluconazole-resistant Candida albicans in vivo

This study evaluated the efficacy of antimicrobial Photodynamic Therapy (aPDT) against fluconazole-resistant Candida albicans in a murine model of oral candidosis. Mice were inoculated with two clinical isolates (R10, R15) and one reference strain (ATCC) of resistant C. albicans to produce oral candidosis. After inoculation, aPDT mediated by Photodithazine® (PDZ) and LED light was performed. The use of PDZ or light only was also investigated. Additional animals were treated with Nystatin (NYS). Untreated or healthy mice were also evaluated. Microbiological evaluation was performed by recovering C. albicans from the tongue via colony-forming units. Animals were killed 24 hours after treatments, and the tongues were removed for histological analysis. Data were analyzed by one-way ANOVA and Tukey test (P < .05). The results demonstrated that all strains showed the same behavior after aPDT and NYS treatment. A significant reduction in C. albicans viability was achieved after both treatments for R15 and ATCC. No significant reduction was verified for C. albicans R10 submitted to aPDT or NYS. The histological analysis revealed that aPDT did not cause side effects on tissues. aPDT was effective for inactivation of two fluconazole-resistant C. albicans of the three strains evaluated.