The Usefulness of Mannan Antigen and Anti-mannan Anti-body in the Diagnosis of Candidemia

Abstract Background Candida species are among the important nosocomial infection agents. Since morbidity and mortality are high in invasive candidiasis, early diagnosis is crucial. Hence, rapid serologic tests are needed for diagnosis. One of these methods is the detection of mannan antigen (Mn) and anti-mannan antibody (A-Mn) in the blood. Objectives In this study, we aimed to evaluate the performance of Mn and A-Mn testing in the diagnosis of candidemia. Methods Seventy-two patients with candidemia, 30 patients with bacteremia, 26 individuals without infection as the control group were included in the study. Candida Mn and A-Mn levels were measured by the ELISA method. Sensitivity, specificity, and negative and positive predictive values were calculated to evaluate the performance of the tests. Results The sensitivity and specificity of the Mn in patients with candidemia were 31.9% and 78.7%, respectively. Mn positivity was significantly higher in neutropenic candidemia patients compared with non-neutropenic candidemia patients (p = 0.026). In the A-Mn test, sensitivity and specificity were 81.9% and 42.6%, respectively, and there was no significant difference between the candidemia and bacteremia groups. It was found that the specificity increased (90.2%) when both tests were used together. Conclusions It was determined that the use of Mn and A-Mn tests alone did not contribute significantly to the diagnosis of candidemia, and the combined use of Mn/ A-Mn tests may be useful. It was concluded that the Mn is a more valuable diagnostic tool in the neutropenic patient group, and regular weekly Mn screening can be recommended in these patients.