Emerging Threat of Wickerhamomyces anomalous (Formerly Candida pelliculosa) in Neonates: A Case Series and Review of Current Evidence.

INTRODUCTION: Neonatal sepsis is a systemic infection in newborn infants within the first month of life. It is a serious condition with a higher rate of mortality, thus it requires prompt recognition and treatment. Invasive candidiasis (IC) is a substantial source of morbidity and mortality in the neonatal intensive care unit (NICU) and the third most frequent cause of late-onset sepsis in very-low-birth-weight (VLBW) newborns. For the IC, the major etiological agent is Candida albicans, but other nonalbicans Candida (NAC) species can also invade the bloodstream and spread the infection. In a recent scenario, the outbreak of Wickerhamomyces anomalous (formerly C. pelliculosa) fungemia in a NICU presents a significant challenge in healthcare settings. This case report series presents six cases of W. anomalous sepsis in neonates admitted to our NICU.

CASE REPORT: The study investigated the clinical and treatment profile of six cases of fungemia originating from the NICU. The objective was to assess the therapy outcome. An automated system (VITEK 2) was used for rapid biochemical identification of Candida species, which revealed W. anomalous growth. Furthermore, the susceptibility of these isolates to antifungal drugs was evaluated using VITEK 2 automated antifungal susceptibility testing (AFST) system. In this case report, we presented six cases of term neonates who were admitted due to respiratory distress. The neonate received numerous antibiotic courses as well as nutrients from a parenteral source due to severe enteral nutrition intolerance. Notably, the four patients did not undergo any invasive procedures; they received only mechanical ventilation support. Subsequently, one patient (Case 6) underwent surgery, and another (Case 5) remained on a ventilator. Neither of the patients who underwent invasive procedures survived. Further, all the W. anomalous isolated from NICU cases were susceptible to fluconazole, voriconazole, and amphotericin B.

CONCLUSION: Our case serves as a reminder to maintain a higher level of suspicion for fungal infections in preterm and term infants in the NICU. Antifungal prophylaxis may be considered for these patients if one or more risk factors are present. Additionally, it is important to note that NAC species can occasionally be the causative agent. Therefore, we should always bear in mind the possibility of these fungal pathogens as infectious agents in neonates with risk factors.