CANDIDA SPP. OTHER THAN CANDIDA ALBICANS: A MAJOR CAUSE OF FUNGAEMIA IN A TERTIARY CARE CENTRE

Candidaemia in a tertiary care centre of developing country: Monitoring possible change in spectrum of agents and antifungal susceptibility

Purpose

Candidaemia is a major cause of morbidity and mortality of hospitalised patients, especially in developing countries. This study was conducted to monitor any change in species distribution and antifungal susceptibility pattern of Candida species causing candidaemia over the last 20 years.

Materials and Methods

The candidaemia cases reported during January 1999 and December 2018 at our centre were reviewed. The yeasts were identified by phenotypic characters (during 1999-2014) and matrix-assisted laser desorption ionisation-time of flight mass spectrometry (MALDI-TOF MS) (during 2014-2018). Antifungal susceptibility testing (AFST) was performed in accordance with the Clinical and Laboratory Standards Institute guidelines.

Results

A total of 602,963 blood samples from patients with suspected sepsis were processed. Candidaemia was diagnosed in 7927 (1.31%) cases. The frequency of cases rose significantly (P = 0.000) in the last quarter of the study. Candida tropicalis (40.1%) was the most common species, followed by Candida albicans (15.2%), Wickerhamomyces anomalus (13.1%), Candida krusei (6.6%), Candida parapsilosis (4.7%) and others. Rare species such as Candida auris, Candida lambica, Candida orthopsilosis, Candida vishwanathii were identified after the introduction of MALDI-TOF. The minimum inhibitory concentrations of amphotericin B rose significantly from the first to last quarter (0.5%-4.9%). Fluconazole resistance was fairly constant at 7.4%-8.8%.

Conclusion

Local epidemiology of candidaemia at our centre was distinct regarding prevalence and change of spectrum of species. The identification of rare species was possible after the introduction of MALDI-TOF. With the emergence of multidrug-resistant C. auris and resistance in other species, routine AFST has become imperative.

Candida tropicalis in the tropics: A rare fungal cause of perinephric abscess

Perinephric and renal abscess are very rare entities with insidious presentation and pose a great diagnostic challenge, common etiology being bacterial. Only less than 30 cases of fungal etiology have been reported in literature. Herein, we report first case of fungal perinephric abscess caused by Candida tropicalis in a young diabetic female who presented with right flank pain and vomiting. Diagnosis made by CT imaging and culture of USG guided aspiration of perinephric abscess revealed growth of Candida tropicalis. Candida tropicalis perinephric abscess requires a very high index of suspicion for diagnosis. Associated high morbidity and mortality rates are likely due to misdiagnosis, therefore fungal perinephric and renal abscess must be kept as differential diagnosis in cases of fever with abdominal pain. Prompt diagnosis and early treatment are important for better outcome. Imaging and microbiological investigations are required for diagnosis, and drainage is indicated for successful therapy.

Biofilm as a virulence marker in Candida species in Nosocomial blood stream infection and its correlation with antifungal resistance

Nosocomial blood stream infections (BSI) due to fungi especially Candida is increasing steadily. A two year prospective study was conducted in the S.C.B. Medical College with an aim to evaluate the species distribution, antifungal susceptibility and biofilm formation of Candida spp. isolated from nosocomial BSIs. 34 Candida spp. were isolated from 359 blood cultures. Antifungal susceptibility was performed by microbroth dilution technique and both visual and spectrophotometric method were used for biofilm detection. C. tropicalis was the common spp. isolated followed by C. parapsilosis and others. Most (92%) of the isolates were susceptible to Amphoterecin-B and highest resistance was observed against Flucytosine (37%) and Fluconazole(35%). Biofilm production and antifungal resistance was observed more in nonalbicans Candida spp.

A review of Candida species causing blood stream infection

The incidence of candidemia has been on a rise worldwide. The epidemiology of invasive fungal infections in general and of candidemia in particular has changed in the past three decades because of a variety of factors like the AIDS epidemic, increased number of patients receiving immunosuppressive therapy for transplantation and the increasing use of antimicrobials in the hospital setups and even in the community. The important risk factors for candidemia include use of broad-spectrum antimicrobials, cancer chemotherapy, mucosal colonization by Candida species, indwelling vascular catheters like central venous catheters, etc. More than 90% of the invasive infections due to Candida species are attributed to five species-Candida albicans, Candida glabrata, Candida parapsilosis, Candida tropicalis and Candida krusei. However, the list of new species of Candida isolated from clinical specimens continues to grow every year. Early diagnosis and proper treatment is the key for management of candidemia cases.