The purpose of the study is to investigate the role of the human immune response to candidemia/invasive candidiasis as it relates to the cytokine interferon-gamma.

In this study, patients with Candida bloodstream infection, peritonitis/intra-abdominal abscess, and pleural empyema will be enrolled.

Persistent candidiasis confirmed by culture will be defined as follows: (i) Candida bloodstream infection present for >48 hours after initiation of effective antifungal treatment and after removal of intravenous devices, (ii) Intra-abdominal infection (peritonitis or abscess) that persists for >96 hours after source control intervention and effective antifungal treatment, (iii) Pleural empyema that persists for >96 hours after placement of drainage catheter and effective antifungal treatment.

Outcomes in patients with and without persistent candidiasis will be assessed.

Subjects must meet all following inclusion criteria to qualify for the study:

1. Willing and able to provide written informed consent. If the subject is unable to consent for himself/herself, a legally authorized representative must provide informed consent on his/her behalf.
2. Males or females ≥18 years of age
3. Patients having one or more systemic signs attributable to candidemia or invasive candidiasis (fever, hypothermia, hypotension, tachycardia, tachypnea, local signs of inflammation).
4. Isolation of Candida from blood, intra-abdominal abscess/peritoneal fluid or pleural fluid.

Exclusion Criteria

Subjects must NOT meet any of the following exclusion criteria to qualify for the study:

1. Severe neutropenia (absolute neutrophil count <500 cells/microL)
2. Profound lymphopenia (<300 cells/microL)
3. The Principal Investigator (PI) is of the opinion the subject should not participate in the study.
4. Females who are pregnant.

Patients with Candida bloodstream infection, peritonitis/intra-abdominal abscess, and pleural empyema