Sodium Gluconate Containing Parenteral Nutrition Solution as a Cause of False Positive Aspergillus Galactomannan Assay in Paediatric Patients with Hematological Malignancies.

Background: The detection of Aspergillus galactomannan antigenemia (GM-Ag) is a contributive method in the diagnosis of invasive aspergillosis (IA). Herein, we report 3 cases of false positive GM-Ag in paediatric patients (pts) receiving NP2 Enfants AP-HP® parenteral nutrition (Fresenius, France), and none of them had or developed IA.

Methods: In December 2006, the sera of these 3 pts (1 allogeneic transplant recipient and 2 neutropenic acute leukaemia pts) taken before, during, and after cessation of NP2 solution were tested for the presence of GM-Ag using the Platelia® Aspergillus kit. This solution, its 30 components and 8 other commercially available solutions for parenteral nutrition were tested for the presence of GM.

Results: GM became detectable within 1 day after IV administration of NP2 with indices up to 9.25, remained positive throughout treatment, and became negative (≤0.5) within 48 hours in 2/3 pts. The NP2 solution and a single one of its components, sodium gluconate (SG), tested positive with GM estimated at 55.4ng/ml. No Aspergillus DNA was detected by real-time PCR. Three NP2 and 6 SG batches from different origins yielded similar results. On the other hand, 6 different batches of calcium gluconate and 8 other commercially available SG-free parenteral nutrition solutions tested negative.

Conclusions: These results suggest a strong cross reactivity of Platelia® kit with SG-containing NP2, as recently described with Plasma-Lyte® (Baxter Distribution Centre Europe). We estimate that clinicians and biologists should become aware of this problem which might lead to inappropriate invasive investigations and/or treatments.