Epidemiology of invasive fungal diseases in patients with hematological malignancies and haematopoietic cell transplantation recipients: Systematic review and meta-analysis of trends over time.

BACKGROUND

Invasive fungal diseases (IFD) are severe complications in patients with hematological malignancies, worsening prognosis, and increasing mortality. Despite extensive research, epidemiological data often lack temporal systematization, hindering interpretation and practical application. The objective was to assess the incidence and etiology of IFDs in oncohematological patients across different therapeutic groups using published studies.

METHODS

A systematic search was conducted in PubMed (Medline), Embase, and Google Scholar. Meta-analyses using primarily random-effects models were performed to estimate IFD incidence, overall etiological structure (proportions of major genera like Aspergillus, Candida, and rare pathogens), and analyze temporal trends (pre- vs. post-2010).

RESULTS

Incidence analysis included 34 publications (47 cohorts; 91,151 participants); etiology analysis included 35 cohorts (4427 isolates). Pooled IFD incidence was significantly higher in allo-HSCT recipients (9.96 %, 95 % CI 8.24-11.83 %) compared to chemotherapy (5.22 %, 95 % CI 3.96-6.65 %) and auto-HSCT (3.39 %, 95 % CI 1.56-5.83 %). Overall, Aspergillus (44.8 %) and Candida (34.1 %) dominated IFD etiology. A numerical shift occurred over time, with Candida proportion (48.6 %) surpassing Aspergillus (38.0 %) after 2010, reversing the pattern seen before 2010 (Candida 30.0 %, Aspergillus 47.8 %). Rare pathogens collectively accounted for ∼12.9 % pre-2010 and ∼8.8 % post-2010. Despite these numerical shifts, no statistically significant overall differences in IFD incidence or the proportions of major/rare pathogen groups were found between the pre- and post-2010 periods based on subgroup difference tests (p > 0.05). Etiology varied significantly by treatment.

CONCLUSION

This comprehensive meta-analysis reveals significant variability in IFD incidence and etiology based on treatment modality, with allo-HSCT conferring the highest risk. While numerical shifts in pathogen distribution occurred over time, statistically significant overall temporal trends were not detected in this dataset for major or rare pathogens. High study heterogeneity is a key limitation. The findings underscore the need for risk-stratified prophylaxis and diagnostics, informing antifungal stewardship strategies tailored to treatment settings.