Six-year experience with GM test in hematological patients in a public Brazilian tertiary hospital

Invasive fungal infection (IFI) is frequent in patients with hematologic malignancies or submitted hematopoietic stem cell transplantation (HSCT).

Objectives: To evaluate the role of the GM (galactomannan) test in prescribing therapeutic antifungals; to determine invasive aspergillosis (IA) frequency, the factors associated with positive GM test, and the in-hospital mortality.

Methods: We conducted a retrospective observational study including patients aged 18 or over with hematological malignancy or submitted to HSCT. GM test was measured twice weekly. The hypothesis of IFI was considered in patients with neutropenia and persistent fever despite broad-spectrum antibiotics.

Results: A total of 496 patients were evaluated; the mean of GM tests performed per patient was 4.2 (+3.1), and 86 (17.3 %) had positive results. IFI was diagnosed in 166 (33.5 %) and IA in 22 (24.6 %) patients. Positive GM test was more frequent in patients with IFI (72.2 % and 25.1 %; OR 8.1; 95 % CI 4.8 - 13.8), and was associated with therapeutic antifungals prescription (52, 9 % and 20.5 %; OR 4.3, 95CI% 2.0 - 9.4), as well as lung abnormalities on HRCT (45.3% vs. 21.5 %; OR 3.0, 95 %CI 1.4 - 6.5). Mortality was 31.6 %. In the multivariate analysis, the variables associated with mortality were the hypothesis of IFI (OR 6.35; 95 % CI 3.63-11.12.0), lung abnormalities on HRCT (57.9 % and 26.9 %; OR 2 0.6; 95 % CI 1.5 - 4.4), and positive GM test (57.9 % and 26.9 %; OR 2.7 95 % CI 1.6 - 4.5).

Conclusions: Positive GM test was associated with lung abnormalities on HRCT and with the introduction of therapeutic antifungals. If adequate anti-mold prophylaxis is available, the GM test should not be used as screening, but to investigate IFI in high-risk patients. The diagnosis of IFI, positive GM test and lung abnormalities on HRCT were predictors of hospital mortality in patients with hematological malignancies or undergoing HSCT.