Impact of Previous Invasive Fungal Infections on the Outcome of Patients Undergoing Allogeneic Hematopoietic Stem Cells

Introduction: Outcome in allogeneic HSCT varies widely depending on disease type, stage, stem cell source, HLA-matched status and conditioning regimen. IFI is a possible complication of HSCT and a prior IFI increases the patient's risk for transplant related mortality due to the possibility of reactivation of the fungal infection. This study aimed to evaluate the impact of a previous IFI history on transplant outcome

Methods: We retrospectively collected the clinical data of patients considered eligible for allogeneic HSCT during 2014 at the Rome Transplant Network (RTN), a JACIE accredited metropolitan transplant program established in Rome since 2006. The observation of patients was continued until 31 December 2015. The diagnosis of IFI were defined as possible, probable and proven as established by European Organization for Research and treatment of Cancer.

Results: Twenty-one (37%) out of 57 eligible patients had an IFI episode before transplant: 6 of the episodes were proven, 4 probable and 11 possible. Overall, 10 (47%) pneumonia, 4 (19%) gastroenteritis, 3 sinusitis, 2 candida sepsis, 1 meningitis and 1 cutaneous abscess were registered. Five out of 21 patients (23%) died before HSCT versus 2 of 36 patients (5%) without previous documented IFI, [OR 5.31 95% CI 0.93- 30.40 , p value 0.06 Fisher Test], .

A larger percentage of patients with past IFI waited HSCT over 6 months from the date of eligibility in comparison with those without previous IFI [43% vs 30% ; OR 1.87 95% CI 0.54-6.40 , p value 0.5 Yates test]; Sixteen (57%) out of 28 dead patients in the pre-transplant period have had a previous IFI episode vs 5(17%) out of patients alive [OR 6.4, 95% CI 1.89-21.68, p value: 0.004 Yates Test].

In the post-transplant period, only 6% of patients with a past IFI, experienced an engraftment in a time of < 15 days, vs 30% of patients without past IFI [OR 4.86 CI 95% 0,5-43,2, p value 0,2 Yates test]. In the post-transplant period, a IFI was diagnosed in 13 (26%) patients; ten (76%) out of 13 patients had a past IFI versus 9 (24%) of the patients without IFI.. [OR 7.87, CI 95% 1,8-34,2, p value 0,005 Yates test].Among the dead HSCT patients, those who had a previous IFI had a lower median survival [160 days (range 22- 480)] compared to patients without a previous IFI who died [196.5 days period (range 20-820)].

Conclusions: A previous IFI episode in the pre transplant period slow the accessibility to the transplant, adversely affects the engraftment, and is significantly associated with increased post-transplant mortality