(1→3)-β-D-glucan and Galactomannan Testing for the Diagnosis of Fungal Peritonitis in Peritoneal Dialysis Patients, a Pilot Study

Fungal peritonitis is an uncommon but serious complication of peritoneal dialysis (PD) due to the fact that routine culture to recovered the etiologic agents are time consuming and KOH staining has very low sensitivity. Peritoneal (1→3)-β-D-glucan (BG) or galactomannan (GM), both fungal cell wall components, are candidate biomarkers of fungal peritonitis. Hence, a comparative cross-sectional analysis of peritoneal dialysis fluid (PDF) BG (Fungitell, Cape Cod, MA, USA) and GM (Platelia Aspergillus Ag kits, Bio-rad, France) from all PD patients with and without fungal peritonitis (13 cases, identified by culture), over a 1 year period, was performed. PDF of the fungal peritonitis group showed very high BG (494 ± 19 pg/ml) and high GM (3.41 ± 1.24) similar results were noted in specimens from cases of peritonitis with other causes, especially gram negative bacterial peritonitis. A BG cut-off value at 240 pg/ml and GM at 0.5 showed sensitivity/ specificity at 100%/ 83% and 77%/ 58%, respectively. A concomitantly positive GM reduced the false positive rate of BG from nonfungal peritonitis. In conclusion, BG and GM in peritoneal fluid with provisional cut-off values were applicable as surrogate biomarkers for the diagnosis of fungal peritonitis in PD patients.