Prophylactic oseltamivir during major seasonal influenza H1N1 outbreak might reduce both H1N1 and associated pulmonary aspergillosis in children undergoing haploidentical transplantation.

Following a major seasonal outbreak of H1N1 influenza in 2018 September, prophylactic oseltamivir for six months was initiated in children undergoing haploidentical HCT with regular monitoring for influenza and other respiratory virus infections. Influenza was not detected in 22 children undergoing prophylaxis, compared to 8 H1N1 infections in 21 adults without prophylaxis (P = .01). Four children on prophylaxis were detected to have other respiratory viruses, compared to 8 in those without prophylaxis. Invasive pulmonary aspergillosis (IPA) was observed only in association with H1N1 (4/8 with H1N1 vs 0/35 without H1N1, P = .001) and was thus lower in the prophylaxis group (P = .04). The overall incidence of episodes of respiratory illness and hospital stay were also lower in those on prophylaxis (P = .001). There were no untoward side effects associated with prophylactic oseltamivir. Prophylactic oseltamivir was safe and effective in prevention of H1N1 infection and subsequent IPA in children at-risk, early after haploidentical HCT.

Impact of extended infusional mesna prophylaxis on the incidence of BK viruria and hemorrhagic cystitis following post-transplantation cyclophosphamide and CTLA4Ig-based haploidentical transplantation.

Hemorrhagic cystitis (HC) has been reported with increased frequency following post-transplantation cyclophosphamide (PTCy)-based haploidentical hematopoietic cell transplantation (HCT) along with a strong association with BK viruria. We prospectively evaluated the incidence of BK viruria and HC in 115 patients (median age 20 years, 2-65) undergoing PTCy-based haploidentical HCT with (n = 71) or without (n = 44) CTLA4Ig. HC prophylaxis consisted of a continuous infusion of mesna 30 min prior and 48 h post-PTCy. The overall incidence of BK viruria was 65.7%. None with BK viruria < 104 copies/ml developed clinical symptoms (n = 65). The incidence of BK viruria ≥ 104 copies/ml was 7.1% (n = 8) and 75% developed HC. The incidence of HC was 5.4% at a median of 30 days. Both BK viruria ≥ 104 copies/ml and HC were strongly associated with acute GVHD (p < 0.001). A higher NRM was observed in those with BK viruria ≥ 104 copies/ml, related to GVHD and its complications (41.7% vs 12.6%, p = 0.04). The incidences of acute GVHD, vis-à-vis, overall BK viruria, BK viruria ≥ 104 copies/ml, and HC, tended to be lower in patients receiving CTLA4Ig. Thus, extended infusional mesna, coupled with significant reduction in alloreactivity along with possible preservation of antiviral immunity associated with the use of CTLA4Ig, was probably responsible for a much lower incidence of BK viruria and resultant HC than reported previously following PTCy-based haploidentical HCT.

Alterations in NKG2A and NKG2C Subsets of Natural Killer Cells Following Epstein-Barr Virus Reactivation in CTLA4Ig-based Haploidentical Transplantation Is Associated With Increased Chronic Graft-Versus-Host Disease.

BACKGROUND: The impact of newer approaches to haploidentical transplantation on Epstein-Barr virus (EBV) is largely unknown. METHODS: We prospectively evaluated the incidence of EBV reactivation and its impact on transplantation outcomes in 71 patients undergoing haploidentical transplantation with posttransplantation cyclophosphamide in combination with CTLA4Ig-based T-costimulation blockade. RESULTS: Eight patients developed EBV reactivation at a median of 96 days with no incidence of lymphoproliferative disorder. There was no impact of EBV reactivation on acute graft-versus-host disease (GVHD), nonrelapse mortality, progression-free, or overall survival. Despite an overall incidence of 19%, there was a significant increase in chronic GVHD following EBV reactivation (62.5% versus 8%; P = 0.01). NKG2A subset of CD56 natural killer cells increased substantially and persisted following EBV reactivation and chronic GVHD, with a reciprocal decrease in NKG2C subset, whereas the reverse was witnessed in those without chronic GVHD (P < 0.01). Increase in NKG2C subset and a decrease in the NKG2A subset were witnessed within 3 months of subsidence of chronic GVHD. CONCLUSIONS: Thus, CTLA4Ig-based haploidentical transplantation was associated with a low incidence of EBV reactivation without EBV-lymphoproliferative disorder. However, EBV reactivation was associated with a sustained alteration in NKG2A and NKG2C subsets of CD56 natural killer cells which might have a pathogenic role in chronic GVHD.

Impact of Preemptive Granulocyte Infusions During Febrile Neutropenia in Patients Colonized with Carbapenem-Resistant Gram-Negative Bacteria Undergoing Haploidentical Transplantation.

We prospectively studied the impact of preemptive granulocyte infusions (pGIs) in 69 patients colonized with carbapenem-resistant gram-negative bacteria (CRGNB) undergoing haploidentical hematopoietic cell transplantation (HCT) compared with a previous cohort of 33 patients who received only antimicrobials directed toward CRGNB at the onset of neutropenic fever (non-pGI group). All patients developed neutropenic fever at a median of day +8 (range, -4 to +12) after transplantation. Engraftment kinetics were similar for both groups. The median number of GIs was 2 (range, 1 to 7), and the median dose of granulocytes infused was 5 × 1010 granulocytes per infusion (range, 1 to 30). The overall incidence of CRGNB bloodstream infections (BSIs) was 21.2% in non-pGI group (7/33) and 17.5% (12/69) in the pGI group (P = .8). However, the CRGNB-related mortality among those with BSI was 100% (7/7) in the non-pGI group versus 16.6% (2/12) in the pGI group (P = .001). The day 100 (4.4% versus 24.4%, P = .002) and 2-year nonrelapse mortality (7.5% versus 35.6%, P = .0001) were significantly reduced in the pGI group. The overall survival at 2 years was 75.6% in the pGI group versus 21.2% in the non-pGI group (P = .0001). Colonization and subsequent BSI with CRGNB are associated with a high incidence of mortality in patients undergoing HCT. pGI reduced early mortality associated with CRGNB in colonized patients undergoing post-transplant cyclophosphamide-based haploidentical HCT.

Gut Colonization with Carbapenem-resistant Enterobacteriaceae Adversely Impacts the Outcome in Patients with Hematological Malignancies: Results of A Prospective Surveillance Study.

BACKGROUND: Gut colonisation with carbapenem-resistant enterobacteriaceae (CRE) is a risk factor for CRE bacteremia and patients with haematological malignancies (HM) are at the highest risk of mortality. METHODS: We conducted a prospective surveillance study of gut colonisation with CRE and its impact on the outcome of 225 consecutive patients of HM over 28 months. RESULTS: The median age of the cohort was 46 years, the majority with acute leukaemia. 48 (21%) patients were colonised with CRE on admission (CAD). Another 46 patients were colonised with CRE in the hospital (CIH). The risk factors for CAD and CIH were a diagnosis of acute leukaemia and duration of hospital stay respectively. CRE accounted for 77% of infection-related mortality (IRM). The incidence of CRE bacteremia in CRE positive patients was 18% (17/94), and mortality in those with CRE bacteremia was 100%. IRM was 35.3% in CIH group compared to 10.5% in the CAD group (p=0.0001). IRM was highest in those with acute myeloid leukaemia (AML) and CIH (54.9% p=0.0001). On multivariate analysis, CIH was the most important risk factor for IRM (HR-7.2). CONCLUSION: Our data demonstrate that a substantial proportion of patients with HM are colonised with CRE without prior hospitalisation, but those with nosocomial colonisation have the highest risk of mortality, particularly in those with AML.