Candidaemia: a 10-year study in an Indian teaching hospital

Emerging threat of candida resistance among neonates at a teaching institute of Jharkhand

Purpose

In the past few decades, candidemia has escalated to worrisome levels, leading to substantial morbidity and mortality in neonates. The rise in anti-fungal drug resistance demands prompt diagnosis and treatment. This study aimed to determine the speciation and susceptibility pattern of Candida species recovered from special care new-born units and identify risk factors for developing candidemia in neonates.

Method

A total of 580 blood samples from clinically suspected septicemic neonates were collected and subjected to culture. Cultures positive for yeasts were sub-cultured on Sabouraud dextrose agar. Identification of a suspected purified colony of Candida was confirmed to the species level by both conventional and automated techniques matrix-assisted laser desorption and ionization time-of-flight mass spectrometry. Anti-fungal susceptibility of isolates was performed by an automated method (VITEK 2 system) using VITEK 2 cards. Multi-variate logistic regression analysis was used to identify risk factors associated with candidemia.

Result

A total of 56 (9.66%) isolates of Candida species were recovered from 580 blood cultures. Non-albicans Candida species predominated with 82.14% of cases, whereas 17.86% of cases were caused by Candida albicans. Candida tropicalis (46.42%) was the most common isolate recovered, followed by Candida albicans (17.8%). Risk factor analyses identified a very low birth weight [odds ratio (OR) =4.05, 95% confidence interval (CI) =2.03-8.08] and prolonged antibiotic therapy (OR = 3.79, 95% CI = 1.7-8.7) among others as significant predictors of candidemia. All the Candida isolates showed 100% sensitivity to voriconazole and micafungin, whereas the overall sensitivities for fluconazole, amphotericin B, caspofungin, and flucytosine were 85.71%, 96.43%, 96.43%, and 91.07%, respectively.

Conclusion

Candidemia is a life-threatening condition in neonates. Identification of Candida species and routine anti-fungal susceptibility is a must to select a suitable and effective anti-fungal therapy to revoke emerging resistance to anti-fungals.

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.

Antibiotic overuse as a risk factor for candidemia in an Indian pediatric ICU

OBJECTIVE

To identify risk factors and mycological characteristics of candidemia in Pediatric ICU of a tertiary-care hospital.

METHODS

Patients were screened for candidemia by blood culture. Recovered isolates were speciated and subjected to antifungal susceptibility testing. For every candidemic patient, three controls were matched for age, underlying diagnosis and period of hospitalization. Premature neonates were also matched for birth-weight. Proportion of cases and controls on specific antibiotics or indwelling devices was compared using Chi-square test, while unpaired t-test was used for comparing the number of antibiotics used and the number of days of antibiotic administration. Concordance between susceptibility testing methods was evaluated using Chi-square test.

RESULTS

Significantly wider spectrum of antibiotic coverage was observed among the 28 candidemic patients. While every patient received antibiotic against enteric gram-negative bacilli, antibiotic usage for additional groups of microorganisms was significantly higher among cases. Association of candidemia with increasing use of indwelling devices was also observed. Endogenous colonization was higher in candidemic infants. Candida albicans was the commonest species (n = 18), followed by C. tropicalis (n = 7). Fluconazole and ketoconazole resistance was observed in 10.7 % cases.

CONCLUSIONS

This information on pediatric candidemia could be used to devise locally-tailored strategies for identifying at-risk patients, underline the importance of routine antifungal susceptibility testing and formulate appropriate guidelines for management.

Recent experience with fungaemia: change in species distribution and azole resistance

Owing to a rise in frequency and change in pattern of cases with fungaemia at our tertiary care centre, we conducted a prospective study for 4 months to understand the epidemiology and outcome of this infection. Detailed case histories including management protocol and outcomes were noted. Records of 140 cases with fungaemia (27.1% adult and 72.9% paediatric patients) were analysed. Although C. tropicalis was the most common yeast isolated, significantly higher isolation of C. guilliermondii (30.4%) and C. pelliculosa (17.6%) was noted in paediatric patients; and C. albicans (26.3%) and C. glabrata (10.5%) in adult patients. Rare species isolated included C. ustus (0.7%) and Trichosporon asahii (2.1%). Mortality was high (56.9% and 47.4%, respectively), in both groups of patients. Resistance to azoles (fluconazole, itraconazole, voriconazole) emerged in C. albicans (12.5-18.8%) and C. tropicalis (10.2-13.6%). Antifungal susceptibility testing report modified the therapy from fluconazole to amphotericin B in 8 patients; 5 survived. In conclusion, the study highlighted the rise of non-albicans Candida species in our hospital with differential distribution in paediatric and adult wards and emergence of azole resistance.

Epidemiology of candidemia in a tertiary care centre of north India: 5-year study

BACKGROUND

To determine the distribution of species of Candida and the risk factors associated with candidemia in Indian population for which we conducted a retrospective study for 5 years in a tertiary care centre of North India.

MATERIALS AND METHODS

Blood samples from 7,297 patients aged from 3 days to 85 years, suspected with candidemia, were collected and tested for Candida. The susceptibility patterns toward fluconazole for the year 2005 isolates were tested by micro-dilution assay as described in the CLSI (M27A-2 method).

RESULTS

Most of the episodes have been caused by species other than C. albicans. Non-albicans candidemia was 79%-80% in both female and male populations. The most frequent species isolated from 275 patients in 5 years (January 2001-December 2005) was C. tropicalis (35.3%), followed by C. albicans (21.5%), C. parapsilosis (20%), C. glabrata (17.5%), C. krusei (3.3%), C. haemulonii (1.5%), and C. guilliermondii (1%). C. parapsilosis was the predominant in the fifth year of the study (2004-2005). Dose-dependent susceptibility to fluconazole was observed in 5% (n = 3) of the strains. Antifungal resistance was found in 11.7% (n = 7), which includes only C. glabrata.

CONCLUSION

These results were comparable to those derived from other regions of India. C. tropicalis has been reported as the predominant species involved in the cases of candidemia. But in 2005 it has moved toward C. parapsilosis. No true antifungal resistance is reported. Further epidemiological surveillance is needed.

Oral itraconazole in treatment of candidemia in a pediatric intensive care unit

OBJECTIVE

To examine efficacy of itraconazole in the treatment of candidemia in critically ill children.

METHODS

We studied retrospectively cases of candidemia seen consecutively in our Pediatric Intensive Care Unit (PICU) over three and half years. Candida isolates from those patients included. Candida albicans--19, C. tropicalis--31, C. guillermondii--9, C.krusei--4 and C. glabrata--1.

RESULTS

Of the 64 patients, 48 (75%) had symptoms suggestive of septicemia and 16 had no symptoms suggestive of septicemia. No antifungal therapy was given to asymptomatic patients; they recovered from candidemia without development of any sequelae. Of the 48 symptomatic patients 11 died before results of fungal culture became available and antifungal therapy could be started. Thirty seven patients were treated with itraconazole (10 mg/kg/day orally or through gastric tube). Seven (18.9 %) of 37 patients died, 3 within first week of antifungal therapy. Thirty (81%) patients recovered; microbiological cure was noted on average by day 14 (range 4-30 days). The mean +/- SD duration of therapy in patients who responded was 24 +/-7 days (range 21-42 days). None had any major side effect.

CONCLUSION

We conclude that oral itraconazole may be effective in treatment of candidemia in children in a PICU where non-C. albicans candida species constituted majority (70%) of all Candida isolates.

Candidemia in a pediatric intensive care unit

OBJECTIVE

To examine the incidence, epidemiology, and clinical characteristics of candidemia in a pediatric intensive care unit.

DESIGN

Retrospective cohort study.

SETTING

Pediatric intensive care unit of a tertiary care teaching and referral hospital in north India.

SUBJECTS

All patients with candidemia from March 1993 to December 1996.

INTERVENTIONS

Patient-related data were analyzed to study candidemia in relation to reason for fungal culture, underlying medical conditions, predisposing factors, Candida isolates, antimicrobial and antifungal treatment, and deaths.

MEASUREMENTS AND MAIN RESULTS

Sixty-four patients with candidemia were identified. The Candida species isolated were Candida tropicalis (48.4%), C. albicans (29.7%), C. guillermondii (14.1%), C. krusei (6.3%), and C. glabrata (1.6%). Thirty-three patients were detected by a high-risk surveillance blood culture, whereas 31 patients were detected while undergoing septic workup. Sixteen (25%) patients were asymptomatic; they recovered without any antifungal therapy and without any sequelae. Of 48 symptomatic patients, 11 died before institution of antifungal therapy; 37 received oral itraconazole (10 mg.kg(-1).day(-1)). Seven (19%) of these 37 patients died. Those who recovered had sterile culture on average by day 14 (range, 4-30) and received the antifungal therapy on average for 24 days (range, 9-42 days). Overall mortality rate was 28.1%, and bivariate analysis showed significant association with Pediatric Risk of Mortality score (p =.0001), presence of symptoms (p =.003), isolation of nonalbicans Candida in general (p =.04) and C. tropicalis specifically (p =.001), and failure to give presumptive antifungal therapy (p =.055). On multivariate analysis, Pediatric Risk of Mortality score and isolation of C. tropicalis were the only significant predictors of mortality.

CONCLUSIONS

Nonalbicans Candida accounted for 70% of candidemia in a pediatric intensive care unit. High-risk surveillance blood cultures aided diagnosis in about half the patients. Severity of illness and isolation of C. tropicalis were significant predictors of mortality.

Epidemiology of Candida species infections in critically ill non-immunosuppressed patients

A substantial proportion of patients become colonised with Candida spp during hospital stay, but only few subsequently develop severe infection. Clinical signs of severe infection manifest early but lack specificity until late in the course of the disease, thus representing a particular challenge for diagnosis. Mostly nosocomial, invasive candidiasis occurs in only 1-8% of patients admitted to hospitals, but in around 10% of patients housed in intensive care units where it can represent up to 15% of all nosocomial infections. We review the epidemiology of invasive candidiasis in non-immunocompromised, critically ill patients with special emphasis on disease trends over time, pathophysiology, diagnostic approach, risk factors, and impact. Recent epidemiological data suggesting that the emergence of non-albicans candida strains with reduced susceptibility to azoles, previously linked to the use of new antifungals for empiric and prophylactic therapy in immunocompromised patients, may not have occurred in the critically ill. Management of invasive candidiasis in these patients will be addressed in the December issue of The Lancet Infectious Diseases.

Systemic Candida infection in University hospital 1997-1999: the distribution of Candida biotypes and antifungal susceptibility patterns

A total of 102 Candida species were isolated from blood cultures from January 1997 to October 1999. Using assimilation of carbohydrate test, 52 (51.0%) of the Candida sp. were identified as C. parapsilosis, 25.5% (26) were C. tropicalis. C. albicans made up 11.8% (12), 6.9% (7) were C. rugosa, 3.8% (4) C. glabrata and 1% (1) C. guilliermondii. No C. dubliniensis was found in the study. In vitro antifungal susceptibility tests showed that all Candida species were sensitive to nystatin, amphotericin B and ketoconazole. Although all isolates remained sensitive to fluconazole, intermediate susceptibility was found in 3 C. rugosa isolates. Antifungal agents with high frequency of resistance were econazole, clotrimazole, miconazole and 5-fluorocytosine. Candida species found to have resistance to these antifungal agents were non-C. albicans.

Outbreak of Pichia anomala infection in the pediatric service of a tertiary-care center in Northern India

An outbreak of nosocomial fungemia due to the unusual yeast, Pichia anomala occurred in the pediatric wards of our hospital over a period of 23 months (April 1996 to February 1998). A total of 379 neonates and children (4.2% admissions) were infected. The probable index case was admitted to the pediatric emergency ward, with subsequent transmission to the premature nursery, pediatric intensive care units, and other children wards. Carriage on the hands of health care personnel was likely to be responsible for dissemination of the fungus. The outbreak could only be controlled after a health education campaign to improve hand-washing practices was instituted and after nystatin-fluconazole prophylaxis to all premature neonates and high-risk infants was introduced. In a case-control study, we identified a lower gestational age, a very low birth weight (<1,500 g), and a longer duration of hospital stay as significant risk factors associated with P. anomala fungemia in premature neonates. We conducted a culture prevalence survey of 50 consecutive premature neonates and found that 28% were colonized with P. anomala at a skin or mucosal site on the date of delivery and that 20% of these neonates subsequently developed P. anomala fungemia. We performed multilocus enzyme electrophoresis on 40 P. anomala outbreak isolates (including patient and health care workers' hand isolates), and the results suggested that these isolates were identical. Our study highlights the importance of P. anomala as an emerging nosocomial fungal pathogen.

New and emerging yeast pathogens

The most common yeast species that act as agents of human disease are Candida albicans, Candida tropicalis, Candida glabrata, Candida parapsilosis, and Cryptococcus neoformans. The incidence of infections by other yeasts has increased during the past decade. The most evident emerging pathogens are Malassezia furfur, Trichosporon beigelii, Rhodotorula species, Hansenula anomala, Candida lusitaniae, and Candida krusei. Organisms once considered environmental contaminants or only industrially important, such as Candida utilis and Candida lipolytica, have now been implicated as agents of fungemia, onychomycosis, and systemic disease. The unusual yeasts primarily infect immunocompromised patients, newborns, and the elderly. The role of central venous catheter removal and antifungal therapy in patient management is controversial. The antibiograms of the unusual yeasts range from resistant to the most recent azoles and amphotericin B to highly susceptible to all antifungal agents. Current routine methods for yeast identification may be insufficient to identify the unusual yeasts within 2 days after isolation. The recognition of unusual yeasts as agents of sometimes life-threatening infection and their unpredictable antifungal susceptibilities increase the burden on the clinical mycology laboratory to pursue complete species identification and MIC determinations. Given the current and evolving medical practices for management of seriously ill patients, further evaluations of the clinically important data about these yeasts are needed.

Fungemia: An increasing problem in a Danish university hospital 1989 to 1994

OBJECTIVE: To present data on episodes of fungemia in a Danish tertiary-care university hospital admitting all types of patients and to compare the data with previous findings from the same hospital. METHODS: Retrospective identification of episodes of fungemia from 1989 to 1994 and collection of data from computerized files at the Clinical Microbiology Department at Rigshospitalet and the Mycology Reference Laboratory at Statens Seruminstitut. RESULTS: The incidence of fungemia increased gradually from 19 episodes in 1989 to 57 episodes in 1994. An earlier report from the same hospital showed 20 to 25 episodes of fungemia per year between 1984 and 1988. Candida albicans was the dominating species during both periods, accounting for 73% of isolates during 1984 to 1988 and 67% during 1989 to 1994. However, in the hematology department where fluconazole has been used extensively, C. albicans constituted 47% of isolates with Candida krusei and Candida glabrata comprising 25%. CONCLUSIONS: The incidence of fungemia in our tertiary-care hospital has increased threefold from 1989 to 1994. Candida albicans was the dominating cause of fungemia but, in the hematology department, this yeast accounted for less than half of the isolates during the same time period.