Patients with aggressive B-cell lymphoma receiving CAR T-cell therapy have a low rate of severe infections despite lack of universal antibacterial and antifungal prophylaxis.

OBJECTIVES: Our aim was to describe the frequency and severity of infectious complications after chimeric antigen receptor (CAR) T-cell therapy in patients with large B-cell lymphoma (LBCL). METHODS: We retrospectively reviewed clinical records of LBCL patients treated with CD19-targeted CAR T-cell therapy from July/2018 to December/2021 at our institution, and identified all infectious episodes from CAR T-cell infusion until disease progression, death or last follow-up. RESULTS: Overall, 137 patients were included. Thirty six percent had received ≥3 previous lines of therapy and 26% an autologous hematopoietic cell transplantation (auto-HCT). Cytokine release syndrome occurred in 87 (64%) patients. Antibacterial prophylaxis was not used in any patient; only 38% received antifungal prophylaxis. Sixty three infectious events were observed in 41 (30%) patients. Fifty two (83%) of the infectious events had at least one pathogen identified (bacteria [n = 38], virus [n = 11], and fungi [n = 3]). Most of the infectious events occurred during hospitalization for CAR-T treatment. Infection-related mortality was observed in two patients. Independent risk factors for infection included male gender, previous auto-HCT, ≥3 lines of treatment and pre-lymphodepletion neutropenia. CONCLUSIONS: Infections after CAR T-cell therapy in patients with lymphoma are frequent but generally not severe. A conservative and tailored antimicrobial prophylaxis seems to be a safe approach.

Histological and microbiological evaluation of surgical wound closure in mouse skin with cyanoacrylate (Histoacryl®) in comparison to poliglecaprone (Monocryl®) traditional suture.

Incisional wound closure is a key surgical step to facilitate tissue healing, reduce the risk of infection and obtain esthetic and functional recovery. Cyanoacrylates such as Histoacryl® have become a popular choice in surgical veterinary practice. However, how Histoacryl® is affecting tissue regeneration and bacterial load in the wound in comparison to poliglecaprone (Monocryl®) traditional suture methods remains to be determined. This work aimed to evaluate how wounded tissue responds to traditional suture with Monocryl® (poliglecaprone 25/4-0) and Histoacryl®, as well as provide evidence of their effects on wound healing in mice. Fortyeight hours after the incisional procedure, wound tissue biopsies were prepared for histological and microbiological analysis. Biopsies were fixed and colored with Mallory's trichrome and hematoxylin-eosin stains. For microbiological assays, biopsies were suspended in tryptic soy broth (TSB) and 1/10 diluted to evaluate the number of CFU in nutrient agar plates. Our results show no differences between Histoacryl® and Monocryl® traditional suture suggesting that both methods could be used to treat wounds in small animals such as rodents.

Genetic diversity and drug resistance of Mycobacterium tuberculosis in Ecuador.

BACKGROUND: The genetic diversity of Mycobacterium tuberculosis in Quito, Ecuador is not well known. OBJECTIVE: To investigate mutations related to drug resistance and bacterial genotypes in M. tuberculosis strains in Ecuador. DESIGN: This was a retrospective study of M. tuberculosis isolates from 104 patients. Isolates were phenotypically resistant to rifampicin (RMP) and/or isoniazid (INH). The genotype was determined using 24-locus mycobacterial interspersed repetitive units-variable-number tandem repeats (MIRU-VNTR). RESULTS: Isolates showed mutations in the rpoB and katG genes, and the inhA promoter. In rpoB, we found 13 genetic alterations at codons 511, 513, 514, 515, 516, 526 and 531. Forty-six (44.2%) RMP-resistant isolates belonged to codon 531. In katG, there were nine genetic alterations at codons 296, 312, 314, 315, 322, 324 and 351. Fifty-three (51%) INH-resistant isolates belonged to codon 315. Five mutations not previously described were identified in katG: Thr324Ser, Thr314Ala, Ala312Pro, Trp351Stop and deleted G at 296 codon. The Latin American Mediterranean (LAM) (33.7%) and Ghana (30.8%) lineages presented most of the main mutations observed. CONCLUSION: This is the first report from Ecuador; it describes five new mutations in katG and indicates that LAM is the most prevalent lineage.

Bet v 1 sensitization modulates allergenic molecular immune response.

Summary: Background Allergy is characterized by allergen-specific IgE production. Molecular-based allergy diagnostic allows to define the precise sensitization profile. Bet v 1 is the major allergen of the PR-10 family. It has been reported that pan-allergens could affect the sensitization panel in adults. This study aimed to evaluate the impact of Bet v 1 sensitization on sensitization pattern in a large sample of children. Methods Serum IgE molecular components were assessed by ISAC method. Sera from 1,205 children, 708 males (58.76%) and 497 females (41.24%), median age 8.61 years (4.93 - 12.54 years) were analyzed. Results A total of 354 PR-10-positive subjects were detected out of 1,205 subjects. Bet v 1 positive children were significantly more frequently sensitized to other molecules belonging to PR-10 family and noteworthy also to other allergenic families than Bet v 1 negative children. Conclusions The present study demonstrates that Bet v 1 sensitization may significantly affect the sensitization pattern in children living in Genoa, a Mediterranean city located in a birch-free area.

Frequency and clinical impact of CDKN2A/ARF/CDKN2B gene deletions as assessed by in-depth genetic analyses in adult T cell acute lymphoblastic leukemia.

Recurrent deletions of the CDKN2A/ARF/CDKN2B genes encoded at chromosome 9p21 have been described in both pediatric and adult acute lymphoblastic leukemia (ALL), but their prognostic value remains controversial, with limited data on adult T-ALL. Here, we investigated the presence of homozygous and heterozygous deletions of the CDKN2A/ARF and CDKN2B genes in 64 adult T-ALL patients enrolled in two consecutive trials from the Spanish PETHEMA group. Alterations in CDKN2A/ARF/CDKN2B were detected in 35/64 patients (55%). Most of them consisted of 9p21 losses involving homozygous deletions of the CDKNA/ARF gene (26/64), as confirmed by single nucleotide polymorphism (SNP) arrays and interphase fluorescence in situ hybridization (iFISH). Deletions involving the CDKN2A/ARF/CDKN2B locus correlated with a higher frequency of cortical T cell phenotype and a better clearance of minimal residual disease (MRD) after induction therapy. Moreover, the combination of an altered copy-number-value (CNV) involving the CDKN2A/ARF/CDKN2B gene locus and undetectable MRD (≤ 0.01%) values allowed the identification of a subset of T-ALL with better overall survival in the absence of hematopoietic stem cell transplantation.

Long-term prognosis for 1-year relapse-free survivors of CD34+ cell-selected allogeneic hematopoietic stem cell transplantation: a landmark analysis.

CD34+ cell selection significantly improves GvHD-free survival in allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, specific information regarding long-term prognosis and risk factors for late mortality after CD34+ cell-selected allo-HSCT is lacking. We conducted a single-center landmark analysis in 276 patients alive without relapse 1 year after CD34+ cell-selected allo-HSCT for AML (n=164), ALL (n=33) or myelodysplastic syndrome (n=79). At 5 years' follow-up after the 1-year landmark (range 0.03-13 years), estimated relapse-free survival (RFS) was 73% and overall survival (OS) 76%. The 5-year cumulative incidence of relapse and non-relapse mortality (NRM) were 11% and 16%, respectively. In multivariate analysis, Hematopoietic Cell Transplantation Comorbidity Index score⩾3 correlated with marginally worse RFS (hazard ratio (HR) 1.78, 95% confidence interval (CI) 0.97-3.28, P=0.06) and significantly worse OS (HR 2.53, 95% CI 1.26-5.08, P=0.004). Despite only 24% of patients with acute GvHD within 1 year, this also significantly correlated with worse RFS and OS, with increasing grades of acute GvHD associating with increasingly poorer survival on multivariate analysis (P<0.0001). Of 63 deaths after the landmark, GvHD accounted for 27% of deaths and was the most common cause of late mortality, followed by relapse and infection. Although prognosis is excellent for patients alive without relapse 1 year after CD34+ cell-selected allo-HSCT, risks of late relapse and NRM persist, particularly due to GvHD.

Tacrolimus plus sirolimus with or without ATG as GVHD prophylaxis in HLA-mismatched unrelated donor allogeneic stem cell transplantation.

HLA-matched related or unrelated donors are not universally available. Consequently, patients can be offered hematopoietic stem cell transplantation (HSCT) from alternative donors, including mismatched unrelated donors (MMURD), known to cause a higher incidence of acute GVHD (aGVHD) and chronic GVHD. In vivo T-cell-depletion strategies, such as antithymocyte globulin (ATG) therapy, significantly decrease the risk of GVHD. We performed a multicenter, retrospective study comparing tacrolimus (TAC) and sirolimus (SIR) with or without ATG in 104 patients (TAC-SIR=45, TAC-SIR-ATG=59) who underwent MMURD HSCT. Use of ATG was associated with a lower incidence, albeit not statistically significant, of grades 2-4 aGVHD (46% vs 64%, P=0.09), no difference in grades 3-4 aGVHD (10% vs 15%, P=0.43), a trend for a lower incidence of moderate/severe chronic GVHD (16% vs 37%, P=0.09) and more frequent Epstein-Barr virus reactivation (54% vs 18%, P=0.0002). There were no statistically significant differences in 3-year overall survival (OS) (TAC-SIR-ATG=40% (95% confidence interval (CI)=24-56%) vs TAC-SIR=54% (95% CI=37-70%), P=0.43) or 3-year cumulative incidence of relapse/progression (TAC-SIR-ATG=40% (95% CI=28-58%) vs TAC-SIR=22% (95% CI=13-39%), P=0.92). An intermediate Center for International Blood & Marrow Transplant Research disease risk resulted in a significantly lower non-relapse mortality and better OS at 3 years. Our study suggests that addition of ATG to TAC-SIR in MMURD HSCT does not affect OS when compared with TAC-SIR alone.

Patterns of infection and infection-related mortality in patients with steroid-refractory acute graft versus host disease.

This study aimed to characterize the incidence, etiology and outcome of infectious episodes in patients with steroid refractory acute GvHD (SR-GvHD). The cohort included 127 adults treated with inolimomab (77%) or etanercept (23%) owing to acute 2-4 SR-GvHD, with a response rate of 43% on day +30 and a 4-year survival of 15%. The 1-year cumulative incidences of bacterial, CMV and invasive fungal infection were 74%, 65% and 14%, respectively. A high rate (37%) of enterococcal infections was observed. Twenty patients (15.7%) developed BK virus-hemorrhagic cystitis and five percent had an EBV reactivation with only one case of PTLD. One-third of long-term survivors developed pneumonia by a community respiratory virus and/or encapsulated bacteria, mostly associated with chronic GvHD. Infections were an important cause of non-relapse mortality, with a 4-year incidence of 46%. In multivariate analysis, use of rituximab in the 6 months before SCT (hazard ratio; HR 4.2; 95% confidence interval; CI 1.1-16.3), severe infection before SR-GvHD onset (HR 5.8; 95% CI 1.3-26.3) and a baseline C-reactive protein >15 UI/mL (HR 2.9; 95% CI 1.1-8.5) were associated with infection-related mortality. High rates of opportunistic infections with remarkable mortality warrant further efforts to optimize long-term outcomes after SR-GvHD.

Colistin-resistant Escherichia coli clinical isolate harbouring the mcr-1 gene in Ecuador.

Colistin resistance mediated by the mcr-1 gene has been reported worldwide, but to date not from the Andean region, South America. We report the first clinical isolate of Escherichia coli harbouring the mcr-1 gene in Ecuador. The strain was isolated from peritoneal fluid from a 14-year-old male with acute appendicitis, and subjected to molecular analysis. The minimum inhibitory concentration of colistin for the strain was 8 mg/ml and it was susceptible to carbapenems but resistant to tigecycline. The strain harboured mcr-1 and bla CTX-M-55 genes and was of sequence type 609. The recognition of an apparently commensal strain of E. coli harbouring mcr-1 serves as an alert to the presence in the region of this recently described resistance mechanism to one of the last line of drugs available for the treatment of multi-resistant Gram-negative infections.

Panniculitis caused by Mycobacterium monacense mimicking erythema induratum: a case in Ecuador.

We report the first case of recently characterized species M. monacense associated with chronic nodular vasculitis, infecting a young woman. This case represents the first isolation of M. monacense from Ecuador. The isolate was identified by conventional and molecular techniques.

Severe infections after single umbilical cord blood transplantation in adults with or without the co-infusion of CD34+ cells from a third-party donor: results of a multicenter study from the Grupo Español de Trasplante Hematopoyético (GETH).

BACKGROUND: Umbilical cord blood transplantation (CBT) is an established alternative source of stem cells in the setting of unrelated transplantation. When compared with other sources, single-unit CBT (sCBT) is associated with a delayed hematologic recovery, which may lead to a higher infection-related mortality (IRM). Co-infusion with the sCBT of CD34+ peripheral blood stem cells from a third-party donor (TPD) (sCBT + TPDCD34+) has been shown to markedly accelerate leukocyte recovery, potentially reducing the IRM. However, to our knowledge, no comparative studies have focused on severe infections and IRM with these 2 sCBT strategies. METHODS: A total of 148 consecutive sCBT (2000-2010, median follow-up 4.5 years) were included in a multicenter retrospective study to analyze the incidence and risk factors of IRM and severe viral and invasive fungal infections (IFIs). Neutrophil engraftment occurred in 90% of sCBT (n = 77) and 94% sCBT + TPDCD34+ (n = 71) recipients at a median of 23 and 12 days post transplantation, respectively (P < 0.01). RESULTS: The 4-year IRM was 24% and 20%, respectively (P = 0.7), with no differences at day +30 (5% and 4%, respectively) and day +100 (10% and 8%, respectively). In multivariate analysis early status of the underlying malignancy, cytomegalovirus (CMV)-seronegative recipient and high CD34+ cell content in the cord blood unit before cryostorage (≥1.4 × 10(5) /kg) were protective of IRM. Among the causes of IRM, bacterial infections and IFIs were more common in sCBT (15% vs. 4%), while CMV disease and parasitic infections were more common in the sCBT + TPDCD34+ cohort (5% vs. 16%). CONCLUSION: These data show that sCBT supported with TPDCD34(+) cells results in much shorter periods of post-transplant leukopenia, but the short- and long-term rates of IRM were comparable to those of sCBT, presumably because immune recovery is equally delayed in both graft types.

Impact of Epstein Barr virus-related complications after high-risk allo-SCT in the era of pre-emptive rituximab.

We monitored 133 high-risk allo-SCT recipients for 6 months after transplant for EBV reactivation by quantitative real-time PCR. Rituximab was given as pre-emptive therapy for viremia >1000 copies/mL. The 1-year cumulative incidence of EBV reactivation was 29.4% (95% confidence interval (CI): 18-40) in patients monitored due to initial high-risk characteristics (n=93) and 31.8% (95% CI: 19.7-44) in those followed because of the development of refractory GVHD (n=40). Overall response rate to Rituximab was 83%. Nine patients (9.6%) developed post-transplant lymphoproliferative disorder (PTLD) at a median of +62 days after SCT. Eight of them showed a concomitant CMV reactivation. Second SCT was the only risk factor associated with EBV infection and PTLD in multivariate analysis (hazard ratio (HR) 2.6 (95% CI: 1.1-6.4; P=0.04) and HR 6.4 (95%CI: 1.3-32; P=0.02)). The development of EBV reactivation was not associated with non-relapse mortality or OS (P=0.97 and P=0.84, respectively).

GVHD prophylaxis with sirolimus-tacrolimus may overcome the deleterious effect on survival of HLA mismatch after reduced-intensity conditioning allo-SCT.

Large studies, mostly based on series of patients receiving CSA/tacrolimus (TKR) plus MTX as immunoprophylaxis, have demonstrated a deleterious effect on survival of the presence of a single mismatch out of eight loci after allogeneic hematopoietic SCT (alloHSCT). We retrospectively analyzed a series of 159 adult patients who received sirolimus(SRL)/TKR prophylaxis after alloHSCT. We compared overall outcomes according to HLA compatibility in A, B, C and DRB1 loci at the allele level: 7/8 (n=20) vs 8/8 (n=139). Donor type was unrelated in 95% vs 70% among 7/8 vs 8/8 pairs, respectively (P=0.01). No significant differences were observed in 3-year OS (68 vs 62%), 3-year EFS (53 vs 49%) and 1-year non-relapse mortality (9 vs 13%). Cumulative incidence of grades II-IV acute GVHD (aGVHD) was significantly higher in 7/8 alloHSCT (68% vs 42%, P<0.001) but no significant differences were found for III-IV aGVHD (4.5% vs 11%), overall (35% vs 53%) and extensive (20% vs 35%) chronic GHVD in 7/8 vs 8/8 subgroups, respectively. In summary, the present study indicates favorable outcomes after alloHSCT using the combination of SRL/TKR combination as GVHD prophylaxis with OS in the range of 55-70%, and non-significant differences in overall outcomes, irrespective of the presence of any mismatches at obligatory loci.

Plerixafor in patients with lymphoma and multiple myeloma: effectiveness in cases with very low circulating CD34+ cell levels and preemptive intervention vs remobilization.

This retrospective study presents data from 105 consecutive multiple myeloma and lymphoma patients who had PB CD34+ cell counts <10/µL on day 4 of steady-state G-CSF mobilization for autologous hematopoietic cell transplantation. Our results confirm the capacity of plerixafor to improve mobilization outcomes in this clinical setting. In addition, they show that the effectiveness of plerixafor, compared with G-CSF only, translates to patients with very low (<3.5/µL) circulating CD34+ cell counts: overnight CD34+ cell count expansion (5.3- vs 1.7-fold), overall CD34+ cell yield (2.29 vs 0.15 × 10(6) CD34+ cells per kg) and patients yielding ⩾2 × 10(6) CD34+ cells per kg (63% vs 3%). Furthermore, our data also show that preemptive plerixafor is significantly more effective and more efficient than in remobilization: CD34+ cell yield in the first apheresis (3.28 vs 2.0 × 10(6) CD34+ cells per kg) and overall (3.73 vs 2.44 × 10(6) CD34+ cells per kg), patients yielding ⩾2 × 10(6) CD34+ cells per kg in the first apheresis (85% vs 44%) and overall (92% vs 64%), all this requiring less days and doses of plerixafor treatment (1.08 vs 1.48). These data would advocate using plerixafor as an early preemptive intervention based on day 4 circulating CD34+ counts, including very high-risk patients with very low circulating levels.