Late-onset severe pneumonia after allogeneic hematopoietic stem cell transplantation: prognostic factors and treatments

COVID-19 was associated with the complications after allogeneic hematopoietic stem cell transplantation

We aimed to identify the severity and duration of COVID-19 infection on complications after allo-HSCT. Enrolled 179 hospitalized patients with COVID-19 were categorized into long-term infection (> 18 days, n = 90) or short-term infection group (≤ 18 days, n = 89) according to the median duration of COVID-19. The severity of COVID-19 was categorized as asymptomatic infection, mild, moderate, severe, and critical illness according to guidelines of National Institutes of Health. Particularly, severe illness and critical illness were classified as serious infection. Asymptomatic infection, mild illness and moderate illness were classified as non-serious infection. The 150-day probabilities of poor graft function (PGF), cytomegalovirus (CMV) pneumonia and non-relapse mortality (NRM) were significantly higher in long-term infection group. The 150-day probabilities of CMV pneumonia and NRM after COVID-19 were higher in serious infection group. The 150-day probabilities of overall survival (OS) was significantly lower in long-term and serious infection group. In multivariable analysis, the severity of COVID-19 was associated with NRM and OS, and the duration of COVID-19 was associated with PGF. In summary, our data reported that the severity and duration of COVID-19 were associated with several complications and contribute to poor outcomes after allo-HSCT.

Clinical manifestations, prognostic factors, and outcomes of adenovirus pneumonia after allogeneic hematopoietic stem cell transplantation

BACKGROUND

Severe pneumonia is one of the most important causes of mortality after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Adenovirus (ADV) is a significant cause of severe viral pneumonia after allo-HSCT, and we aimed to identify the clinical manifestations, prognostic factors, and outcomes of ADV pneumonia after allo-HSCT.

METHODS

Twenty-nine patients who underwent allo-HSCT at the Peking University Institute of Hematology and who experienced ADV pneumonia after allo-HSCT were enrolled in this study. The Kaplan-Meier method was used to estimate the probability of overall survival (OS). Potential prognostic factors for 100-day OS after ADV pneumonia were evaluated through univariate and multivariate Cox regression analyses.

RESULTS

The incidence rate of ADV pneumonia after allo-HSCT was approximately 0.71%. The median time from allo-HSCT to the occurrence of ADV pneumonia was 99 days (range 17-609 days). The most common clinical manifestations were fever (86.2%), cough (34.5%) and dyspnea (31.0%). The 100-day probabilities of ADV-related mortality and OS were 40.4% (95% CI 21.1%-59.7%) and 40.5% (95% CI 25.2%-64.9%), respectively. Patients with low-level ADV DNAemia had lower ADV-related mortality and better OS than did those with high-level (≥ 106 copies/ml in plasma) ADV DNAemia. According to the multivariate analysis, high-level ADV DNAemia was the only risk factor for intensive care unit admission, invasive mechanical ventilation, ADV-related mortality, and OS after ADV pneumonia.

CONCLUSIONS

We first reported the prognostic factors and confirmed the poor outcomes of patients with ADV pneumonia after allo-HSCT. Patients with high-level ADV DNAemia should receive immediate and intensive therapy.

Clinical characteristics and outcomes of allogeneic hematopoietic stem cell transplantation recipients with coronavirus disease 2019 caused by the Omicron variant: a prospective, observational cohort study

We aimed to describe the clinical characteristics, particularly the occurrence and risk factors of severe/critical illness, in allogeneic hematopoietic stem cell (allo-HSCT) recipients infected with coronavirus disease 2019 (COVID-19) caused by Omicron variant in an observational prospective study (n = 311). The median time from allo-HSCT to COVID-19 diagnosis was 8.5 months (range 0.8-106.1) months. Four patients (1.3%) were reported to be asymptomatic during Omicron variant infection, and 135 (43.4%) patients showed lower respiratory tract disease. Thirty-four (10.9%) patients were categorized into serious infection (severe illness n = 25; critical illness n = 9) and the median duration from COVID-19 diagnosis to serious infections was 6 days (range, 0-29) days. Thirteen (4.2%) and 6 (1.9%) patients required intensive care unit care and invasive mechanical ventilation, respectively. Receiving more than 1 type of immunosuppressive therapies at COVID-19 diagnosis was associated with severity and persistence of infection. Six patients (1.9%) died after diagnosis of COVID-19 infection. The 4-week probability of overall survival after COVID-19 diagnosis was 98.7%, which was 100% and 88.2% for non-serious and serious infection group (P < 0.001), respectively. Thus, we observed a relatively low serious infection and mortality rate in allo-HSCT recipients infected with COVID-19 caused by Omicron variant.

[Relationship between treatment and prognosis in patients with late-onset severe pneumonia after allogeneic hematopoietic stem cell transplantation]

OBJECTIVE

To explore the relationship between drug treatment and outcomes in patients with late-onset severe pneumonia (LOSP) after allogeneic stem cell transplantation (allo-SCT).

METHODS

We retrospectively analyzed the effects of the initiation time of treatment drugs, especially antiviral drugs and glucocorticoids on the clinical outcomes in 82 patients between January 2016 and August 2021 who developed LOSP after allo-SCT in Peking University People's Hospital. Univariate analysis was performed by Mann-Whitney U test and χ² test, and multivariate analysis was performed by Logistic regression. When multiple groups (n>2) were involved in the χ² test, Bonferroni correction was used for the level of significance test.

RESULTS

Of all 82 patients in this study, the median onset time of LOSP was 220 d (93-813 d) after transplantation, and the 60-day survival rate was 58.5% (48/82). The median improvement time of the survival patients was 18 d (7-44 d), while the median death time of the died patients was 22 d (2-53 d). Multivariate analysis showed that the initiation time of antiviral drugs from the onset of LOSP (< 10 d vs. ≥10 d, P=0.012), and the initiation time of glucocorticoids from antiviral drugs (< 10 d vs. ≥10 d, P=0.027) were the factors affecting the final outcome of the patients with LOSP at the end of 60 d. According to the above results, LOSP patients were divided into four subgroups: group A (antiviral drugs < 10 d, glucocorticoids ≥10 d), group B (antiviral drugs < 10 d, glucocorticoids < 10 d), group C (antiviral drugs ≥10 d, glucocorticoids ≥10 d) and group D (antiviral drugs ≥10 d, glucocorticoids < 10 d), the 60-day survival rates were 91.7%, 56.8%, 50.0% and 21.4%, respectively.

CONCLUSION

Our study demonstrated that in patients who developed LOSP after allo-SCT, the initiation time of antiviral drugs and glucocorticoids were associated with the prognosis of LOSP, and the survival rate was highest in patients who received antiviral drugs early and glucocorticoids later. It suggested that for patients with LOSP of unknown etiology should be highly suspicious of the possibility of a secondary hyperimmune response to viral infection.

Mesenchymal stromal cell treatment improves outcomes in children with pneumonia post-hematopoietic stem cell transplantation: a retrospective cohort study

BACKGROUND

Hematopoietic stem cell transplantation (HSCT) is a standard therapy strategy for most malignant disorders in children. However, transplant-related pneumonia remains a major therapy challenge and mesenchymal stromal cells (MSCs) are rarely reported in HSCT-related pneumonia. The aim of our study was to assess the efficacy of MSC for HSCT-related pneumonia in children.

METHODS

We retrospectively retrieved HSCT-related (severe and non-severe) pneumonia cases (aged < 18 years), which underwent MSC treatment (MSC group) or non-MSC treatment (non-MSC group) in Guangzhou Women and Children's Medical Center, from December 2017 to December 2019. We investigated outcomes of the two different treatments among severe cases and non-severe cases, respectively. The primary endpoints were differences in overall cure rate and time to cure between MSC and non-MSC groups. The secondary endpoints were 180-day overall survival and cumulative cure rate.

RESULTS

Finally, 31 severe pneumonia cases (16 in MSC group, 15 in non-MSC group) and 76 non-severe cases (31 in MSC group, 45 in non-MSC group) were enrolled in this study. Among severe pneumonia cases, overall cure rate in MSC group was significant higher than that in non-MSC group (12[75.0%] vs. 5[33.3%]; OR = 6.00, 95% CI [1.26-28.5]; p = 0.020); the time (days) to cure in MSC group was dramatically reduced compared with that in non-MSC group (36 [19-52] vs. 62 [42-81]; OR = 0.32, 95% CI [0.12-0.88]; p = 0.009); the 180-day overall survival in MSC group was better than that in non-MSC group (74.5% [45.4-89.6] vs. 33.3% [12.2-56.4]; p = 0.013). Among non-severe pneumonia cases, the time (days) to cure in MSC group was notably decreased compared with that in non-MSC group (28 [24-31] vs. 33 [26-39]; OR = 0.31, 95% CI [0.18-0.56]; p = 0.003). Compared with non-MSC group, MSC-treated patients achieved significant improvements of cumulative cure rate not only in severe pneumonia cases (p = 0.027), but also in non-severe cases (p < 0.001).

CONCLUSIONS

This study revealed that MSC treatment could contribute to improving outcomes in children with pneumonia post-HSCT, especially in severe cases. These findings suggest MSC treatment as a promising therapy for HSCT-related pneumonia in children.

A Predicted Model for Refractory/Recurrent Cytomegalovirus Infection in Acute Leukemia Patients After Haploidentical Hematopoietic Stem Cell Transplantation

Objective

We aimed to establish a model that can predict refractory/recurrent cytomegalovirus (CMV) infection after haploidentical donor (HID) hematopoietic stem cell transplantation (HSCT).

Methods

Consecutive acute leukemia patients receiving HID HSCT were enrolled (n = 289). We randomly selected 60% of the entire population (n = 170) as the training cohort, and the remaining 40% comprised the validation cohort (n = 119). Patients were treated according to the protocol registered at https://clinicaltrials.gov (NCT03756675).

Results

The model was as follows: Y = 0.0322 × (age) – 0.0696 × (gender) + 0.5492 × (underlying disease) + 0.0963 × (the cumulative dose of prednisone during pre-engraftment phase) – 0.0771 × (CD34+ cell counts in graft) – 1.2926. The threshold of probability was 0.5243, which helped to separate patients into high- and low-risk groups. In the low- and high-risk groups, the 100-day cumulative incidence of refractory/recurrent CMV was 42.0% [95% confidence interval (CI), 34.7%–49.4%] vs. 63.7% (95% CI, 54.8%–72.6%) (P &lt; 0.001) for total patients and was 50.5% (95% confidence interval (CI), 40.9%–60.1%) vs. 71.0% (95% CI, 59.5%–82.4%) (P = 0.024) for those with acute graft-versus-host disease. It could also predict posttransplant mortality and survival.

Conclusion

We established a comprehensive model that could predict the refractory/recurrent CMV infection after HID HSCT.

Clinical Trial Registration

https://clinicaltrials.gov, identifier NCT03756675.

A Scoring System for Predicting the Prognosis of Late-Onset Severe Pneumonia after Allogeneic Hematopoietic Stem Cell Transplantation

Late-onset severe pneumonia (LOSP) is defined as severe pneumonia developing during the late phase of allogeneic hematopoietic stem cell transplantation (allo-HSCT). Because of the high mortality in patients with LOSP, it is important to identify prognostic factors. In this study, we aimed to develop a risk score system with broad applicability that can help predict the risk of LOSP-associated mortality. We retrospectively analyzed 100 patients with LOSP after allo-HSCT between June 2009 and July 2017. The assessment variables included immune, nutritional, and metabolic parameters at the onset of LOSP. Of these 100 patients, 45 (45%) eventually died, and 55 (55%) were positive for organisms, most commonly viruses. In the multivariate analysis, higher monocyte count (≥0.20 × 10⁹/L versus <0.20 × 10⁹/L; P = .001), higher albumin level (≥30.5 g/L versus <30.5 g/L; P = .044), lower lactic dehydrogenase level (<250 U/L versus ≥250 U/L; P = .008) and lower blood urea nitrogen concentration (<7.2 mmol/L versus ≥7.2 mmol/L; P = .026) at the onset of LOSP were significantly associated with better 60-day survival. A risk score system based on the foregoing results showed that the probability of 60-day survival decreased with increasing risk factors, from 96.3% in the low-risk group to 49.1% in the intermediate-risk group and 12.5% in the high-risk group. Our results indicate that this scoring system using 4 variables can stratify patients with different probabilities of survival after LOSP, which suggests that patients' immune, nutritional, and metabolic status are crucial factors in determining outcome.

Ruxolitinib is an effective salvage treatment for multidrug-resistant graft-versus-host disease after haploidentical allogeneic hematopoietic stem cell transplantation without posttransplant cyclophosphamide

The purpose of our study is to identify the efficacy of ruxolitinib in human leukocyte antigen (HLA) haploidentical hematopoietic stem cell transplantation (haplo-HSCT) recipients with multidrug-resistant (MDR)-graft-versus-host disease (GVHD, n = 34). MDR-GVHD was defined as GVHD showing no improvement after at least 3 types of treatments. The median number of previous GVHD-therapies was 4 for both MDR-acute GVHD (aGVHD) and MDR-chronic GVHD (cGVHD). For MDR-aGVHD (n = 15), the median time to response was 10 days (range 2 to 65), and the overall response rate (ORR) was 60.0% (9/15), including 40.0% (6/15) complete response (CR) and 20.0% (3/15) partial response (PR). The 1-year probability of overall survival after ruxolitinib was 66.7%. The rates of hematologic and infectious toxicities were 73.3% and 46.7% after ruxolitinib treatment. For MDR-cGVHD (n = 19), the median time to response was 29 days (range 6 to 175), and the ORR was 89.5% (17/19), including 26.3% (5/19) CR and 63.2% (12/19) PR. All patients remained alive until our last follow-up. The rates of hematologic and infectious toxicities were 36.8% and 47.4% after ruxolitinib treatment. Ruxolitinib is an effective salvage treatment for MDR-GVHD in haplo-HSCT recipients.

Positive stool culture could predict the clinical outcomes of haploidentical hematopoietic stem cell transplantation

We aimed to identify the effect of positive stool cultures (PSCs) on the clinical outcomes of patients undergoing haploidentical hematopoietic stem cell transplantation (haplo-HSCT) (n = 332). PSCs were observed in 61 patients (PSC group, 18.4%). Enterobacteriaceae in stool specimens was associated with a higher risk of bloodstream infection, and Candida in stool specimens was related to a higher risk of platelet engraftment failure. The cumulative incidence of infection-related mortality 1 year after haplo-HSCT in the PSC group was higher than that of the patients who showed persistently negative stool cultures (NSC group; 19.2% vs. 8.9%, P = 0.017). The probabilities of overall survival (71.4% vs. 83.8%, P = 0.031) and disease-free survival (69.6% vs. 81.0%, P = 0.048) 1 year after haplo-HSCT for the PSC group were significantly lower than those for the NSC group, particularly for patients who had Candida in their stool specimens. In multivariate analysis, Candida in stool specimens significantly increased the risk of mortality and was associated with poorer survival. Our results showed that PSC influenced the clinical outcomes after haplo-HSCT, particularly those who had Candida in their stool specimens.

Treatment of late-onset hemorrhagic cystitis after allogeneic hematopoietic stem cell transplantation: the role of corticosteroids

We aimed to evaluate the treatments, particularly the role of corticosteroids, in patients with late-onset hemorrhagic cystitis (LOHC) after allogeneic hematopoietic stem cell transplantation (allo-HSCT). One hundred and sixty-three consecutive patients who underwent non-T-cell-depleted allo-HSCT and met the criterion of LOHC after allo-HSCT were enrolled in this study. The median time from allo-HSCT to the occurrence of LOHC was 29 (range, 4–155) days. Pathogens identified in blood and/or urine samples from 143 patients were mostly viruses. All of the patients with LOHC received intravenous fluid hydration, alkalization, and forced diuresis, of which 2 patients achieved complete remission (CR) after these treatments. The remaining 161 patients received anti-infection therapies and 71 achieved CR after the therapies. Corticosteroids were additionally applied to 83 out of 90 patients who did not achieve CR after anti-infection therapies, and 88.0% (n = 73) of them showed a grade 3 to 4 LOHC at the beginning of corticosteroid therapy. Thirty-five patients showed an immediate response (CR or downgraded at least one grade) within 1 week after the beginning of the corticosteroid therapy. Sixty-four patients (77.1%) achieved CR after corticosteroid therapy, and the median period from the beginning of corticosteroid therapy to CR was 17 days. Thus, we observed that viruses were the most common pathogens in LOHC after allo-HSCT and that anti-infection therapies were critical. For patients not showing a satisfactory response to anti-infection therapies, additional corticosteroid therapy may help to achieve CR.

Utility of flexible bronchoscopy with polymerase chain reaction in the diagnosis and management of pulmonary infiltrates in allogeneic HSCT patients

Objectives

Pulmonary infiltrates in allogeneic hematopoietic stem cell transplant (allo‐HSCT) patients are potentially life‐threatening and require early diagnosis and treatment. We aimed to retrospectively explore the clinical efficacy of polymerase chain reaction (PCR) in conjunction with flexible bronchoscopy (FB) in allo‐HSCT patients with pulmonary infiltrates.

Patients and methods

We retrospectively reviewed all patients undergoing FB after allo‐HSCT at the Peking University Institute of Hematology from January 2013 to December 2016. We used PCR to detect various viruses in FB specimens, particularly for 27 viruses.

Results

One hundred forty‐nine diagnostic FBs were performed in 130 patients. The overall diagnostic yield was 58%. Eighty‐nine percent of the patients with a positive FB result were diagnosed with a pulmonary infection. Viruses were the most common infectious diagnosis (70%), followed by fungi (48%), bacteria (38%), and Pneumocystis jirovecii (12%). Multivariate analyses showed that a chest computed tomography (CT) finding of diffuse pulmonary infiltrates (P = .012) and positive results in assisted microbiological and serological analyses (P = .000) predicted a positive FB result. FB results prompted a treatment modification in 61% of cases.

Conclusions

FB in conjunction with PCR is efficient in the rapid diagnosis and management of pulmonary infiltrates in allo‐HSCT patients.

[Clinical value of PCR for viral detection of bronchoalveolar lavage fluid in the diagnosis and treatment of pneumonia after allogeneic hematopoietic stem cell transplantation]

Objective: To analyze the clinical value of real-time PCR for virus detection in the diagnosis and treatment of patients after allo-HSCT who had no infection evidence of pneumonia using routine pathogen detection panel. Methods: The clinical data of 71 episodes with acute lung injury from May 2015 to March 2017 after allo-HSCT in hematology department of Peking University People's Hospital (PKUPH) were retrospectively analyzed. PCR for virus detection and other routine pathogen detection tests were performed on bronchoalveolar lavage fluid (BALF) samples. Results: Among 71 episodes with acute lung injury, a total of 15 patients were diagnosed as lower respiratory tract disease merely associated with virus (detection rate of 21.13%) , 19 episodes were absent of lower respiratory tract infection. The median time from allo-HSCT to the occurrence of lung injury were 176 (49-1 376) d and 196 (57-457) d respectively (z=-0.191, P=0.864) . There were no statistical differences for baseline characteristics and clinical features between two groups. The 100-day attributable mortalities were 13.3% (2/15) and 26.3% (5/19) (χ(2)=0.864, P=0.426) . Patients with low-dose steroids treatment had favorable outcome than those with high-dose steroids treatment (the dose of methylprednisolone ≥250 mg/d as standard) [4.2% (1/24) vs 60.0% (6/10) ]. In patients with detectable virus in BALF, 2 patients died with early high-dose steroids treatment, while 11 patients survived with no steroids treatment or late application. Conclusions: Virus infection should be considered in post-HSCT pneumonia patient with negative result using routine pathogen detection panel. Expanding virus detection panel by PCR in BALF could increase diagnostic precision and might be instructive to treatment.

Low-dose post-transplant cyclophosphamide can mitigate GVHD and enhance the G-CSF/ATG induced GVHD protective activity and improve haploidentical transplant outcomes

Use of high-dose, post-transplant cyclophosphamide (PTCy) results in low rates of graft-versus-host-disease (GVHD) and favorable immune reconstitution, although with higher rates of relapse and somewhat high rates of graft failure. We hypothesized that permissible dose reduction of PTCy might be feasible. The current study attempts to establish a murine model and focus on regulatory T cells (Tregs) to clarify the immunological mechanisms for GVHD prevention by low-dose PTCy. In addition, a prospective, clinical cohort study in haploidentical, T-cell replete transplantation is initiated to support the rational. We found that acute GVHD could be alleviated by low-dose PTCy and could be further mitigated after the combined use of low-dose PTCy and antithymocyte globulin (ATG) in mice. Flow-cytometric analyses in mice showed that low-dose PTCy could increase the number of Tregs and the effect on Tregs is significantly prominent with the combined use of low-dose PTCy and ATG. In the clinical cohort study, the cumulative incidence of grades II-IV acute GVHD in combined treatment cohort with low-dose PTCy and ATG/granulocyte colony-stimulating factor (G-CSF) (17%; 95% CI, 5-29%) was significantly lower than both that in matched-pair cohort (33%; 95% CI, 25-41%; P = 0.04) and that in historical cohort (56%; 95% CI, 42-70%; P < 0.001). In-vivo immune reconstitution analysis showed that low-dose PTCy could facilitate suppressive Tregs reconstitution. In conclusion, low-dose PTCy is sufficient for GVHD abrogation under lymphopenic situation and can enhance the protective effect of ATG/G-CSF on GVHD. Intensified conditioning followed by low-dose PTCy might be a feasible option for patients undergoing haploidentical transplantation.

Late-onset severe pneumonia after allogeneic hematopoietic stem cell transplantation: prognostic factors and treatments

Background

In this study, we aimed to evaluate the prognostic factors associated with and treatments for late‐onset severe pneumonia (LOSP) in patients who underwent allogeneic hematopoietic stem cell transplantation (allo‐HSCT).

Methods

Fifty consecutive patients who underwent non‐T‐cell‐depleted allo‐HSCT at the Peking University Institute of Hematology and met the criterion of LOSP after allo‐HSCT were enrolled.

Results

The median time from allo‐HSCT to the occurrence of LOSP was 231 (90–1487) days. Twenty‐eight patients harbored 1 or more pathogens (infectious LOSP, I‐LOSP), whereas 22 did not harbor any pathogens (non‐infectious LOSP, NI‐LOSP). The 100‐day survival rate of LOSP patients was 31.1%. Patients smoking before allo‐HSCT (0% vs. 35.4%, P = 0.002) and male gender (20.0% vs. 61.9%, P = 0.026) had lower 100‐day survival rate. Patients with a lower bronchoalveolar lavage fluid (BALF) neutrophil percentage had higher 100‐day survival rate relative to those with higher BALF neutrophil percentage (45.5% vs. 16.7%, P = 0.012). The 100‐day survival rate of patients with I‐LOSP was lower than that of patients with NI‐LOSP (19.1% vs. 46.9%, P = 0.043). Patients given late (≥1 week after LOSP diagnosis) and low‐dose methylprednisolone (MP) therapy (≤2 mg/kg/day) had the best 100‐day survival rate. In the multivariate analysis, nonsmoking before allo‐HSCT and late and low‐dose MP therapy were significantly associated with a better survival after LOSP.

Conclusion

LOSP is a severe complication after allo‐HSCT. The correct timing and corticosteroid dosage in the context of broad‐spectrum antimicrobial therapy might further improve the outcomes of patients with LOSP.