Table 1.
Factors that can lead to false-positive and false-negative results with the galactomannan test.63
| False-positive (and cross-reactions) | False-negative |
|---|---|
| Biochemical alterations | Presence of anti-Aspergillus antibodies forming immune complexes |
| Bilirubin ≥20 mg/L | |
| Triglycerides ≥200 mg/dL | |
| Hemoglobin ≥500 mg/dL | |
| Use of cytotoxic chemotherapeutic agents (promoting damage to the intestinal mucosa) | Storage of samples at room temperature for a prolonged period before processing |
| Graft versus host disease and autoreactive antibodies | High serum albumin levels |
| Bacteremia by Pseudomonas spp. or Escherichia coli | Presence of galactomannan-degrading enzymes in biological material |
| Use of β-lactams such as piperacillin-tazobactam, amoxicillin/clavulanic acid | Prior use of antifungal agents |
| IFIs by other fungi: | Chronic granulomatous disease and Job's syndrome (hyperimmunoglobulin E) |
| Fusarium | |
| Cryptococcus | |
| Histoplasma | |
| Penicilium | |
| Alternaria | |
| Paecilomyces | |
| Geotricum | |
| Yarrowia lipolytica | |
| Alterations of intestinal mucosa (intake of cereal and cow milk) | Lack of neutropenia |
| Neonates colonized by Bifidobacterium spp. | |
| Gluconate-containing Plasma-Lyte | |
| Other intravenous fluids containing gluconate | |
| Possibly cardboard or soybean protein |