Respiratory virus infection after allogeneic hematopoietic stem cell transplant in a tropical center: Predictive value of the immunodeficiency scoring index

Background

Respiratory virus infection (RVI) is a prevalent infection in patients after allogeneic hematopoietic stem cell transplant (allo‐HSCT) and can result in significant morbidity and mortality. Ability to assess the potential severity of RVI is important in the management of such patients.

Methods

We reviewed the cases of RVI in allo‐HSCT recipients and explored the predictive value of the immunodeficiency scoring index (ISI) established for respiratory syncytial virus (RSV) and its applicability for RVI caused by other respiratory viruses.

Results

RVI occurred year‐round in our tropical transplant center, with peaks in the middle and end of the year. Ninety‐five of the 195 recipients developed a total of 191 episodes of RVI, giving a cumulative incidence of 28% by 6 months and 52% by 24 months for the first episode of RVI. RSV, influenza, rhinovirus, and parainfluenza were the most common viruses. Pneumonia occurred in 63.64%, 42.31%, and 32.42% of adenovirus, influenza, and RSV RVI episodes, respectively, but was also non‐negligible in the more benign viruses, such as coronavirus (31.58%) and rhinovirus (23.68%). Nineteen of the 63 episodes of viral pneumonia required mechanical ventilation and 14 deaths occurred within 6 weeks of the RVI. Receiver operating characteristic analysis showed that an ISI of ≥8 predicted pneumonia with a positive predictive value of >80% for RVI caused by RSV, influenza, adenovirus, and parainfluenza, while it was not predictive for coronavirus and rhinovirus.

Conclusions

The ISI is a useful aid for decision‐making during clinic consultation for patients presenting with symptoms suggestive of an RVI.

Clinicopathological features and outcome of chronic lymphocytic leukaemia in Chinese patients

Chronic lymphocytic leukaemia (CLL) is uncommon in Chinese population and its biology, genetics and treatment outcome in Chinese patients have not been comprehensively investigated. In this study, we studied the clinicopathological features and outcome of 212 Chinese patients with newly diagnosed CLL in Hong Kong and Singapore. The median age at diagnosis was 64 years. The majority of patients presented with early-stage disease (Binet stage A, 56.1%). Del(13)(q14) was the most frequent abnormality (41.7%) detected by fluorescence in situ hybridization (FISH) analysis. Del(17p) and TP53 gene mutations were detected in 7.8% and 8.2% of patients, respectively. MYD88 mutations were found at a higher frequency (11.5%) than expected. CLL with unmutated variable region of the immunoglobulin heavy chain genes (IGHV) occurred in only 31.2% of cases, and was associated with advanced-stage disease (p <0.01) and adverse FISH abnormalities (p<0.01). With a median follow-up of 39 months, the median overall survival (OS) was 108 months. The presence of del(17p) or TP53 mutations was associated with a significantly shorter time to first treatment and an inferior OS (p <0.01). Unmutated IGHV was also associated with a significantly shorter time to treatment (p <0.01). Among patients who required treatment, the median OS and progression-free survival (PFS) were 107 and 23 months, respectively. The presence of del(17p) was associated with a significantly inferior OS and PFS (p <0.01). In summary, Chinese CLL patients had similar genetic aberrations at diagnosis compared with those of Western populations. FISH abnormalities are major factors affecting outcome.

Long-term renal outcome after allogeneic hemopoietic stem cell transplant: A comprehensive analysis of risk factors in an Asian patient population

Allogeneic hemopoietic stem cell transplantation (allo-HSCT) poses a significant challenge to renal function due to multiple drug- and complication-related renal toxicity. In this single-center series of 216 adult Asian patients with a long and complete follow-up, 41 developed chronic kidney disease (CKD) giving a cumulative incidence of 19.0% at 25 years (median follow-up duration 7.84 years, range 2.0-27.7 years), but only two of the 41 patients reached stage 4 CKD and another two required dialysis. In contrast, acute kidney injury occurred in most patients, where glomerular filtration rate (GFR) suffered a mean fall of 50 mL/min/1.73 m² at 6 months post-transplant compared with baseline. Suppression of renal function may last beyond 6 months but is potentially reversible, although not to baseline level in most patients. Analysis of a comprehensive range of 18 risk factors showed that older age, lower GFR at transplant, unrelated donor, diagnosis of AML, presence of diabetes mellitus at transplant, and duration of foscarnet use were significantly associated with CKD development, with the first three remaining as independent risks for CKD in multivariate analysis. Long-term survival is not affected by renal function, being 78.6% as compared to 85.5% for patients with low vs normal GFR at 2 years, respectively.

Isomorphic coalescence of aster cores formed in vitro from microtubules and kinesin motors

We report fluorescence microscopy studies of the formation of aster-like structures emerging from a cellular element-based active system and a novel analysis of the aster condensation. The system consists of rhodamine labeled microtubules which are dynamically coupled by functionalized kinesin motor proteins cross-linked via streptavidin-coated quantum dots (QDs). The aster-shaped objects contain core structures. The cores are aggregates of the QD-motor protein complexes, and result from the dynamic condensation of sub-clusters that are connected to each other randomly. The structural specificity of the aster core reflects a configuration of the initial connectivity between sub-clusters. Detailed image analysis allows us to extract a novel correlation between the condensation speed and the sub-cluster separation. The size of the core is scaled down during the condensation process, following a power law dependence on the distance between sub-clusters. The exponent of the power law is close to two, as expected from a geometric model. This single exponent common to all the contractile lines implies that there exists a time regime during which an isomorphic contraction of the aster core continues during the condensation process. We analyze the observed contraction by using a model system with potential applicability in a wide range of emergent phenomena in randomly coupled active networks, which are prevalent in the cellular environment.

Role of Surveillance Imaging in Patients With Peripheral T-Cell Lymphoma

INTRODUCTION

The role of surveillance imaging (SI) in patients with peripheral T-cell lymphoma (PTCL) in first complete remission (CR1) is unclear.

MATERIALS AND METHODS

Patients with PTCL were identified through prospectively maintained T-cell lymphoma databases from the National Cancer Centre Singapore/Singapore General Hospital and Weill-Cornell Medical College after institutional review board approval. Patients with leukemia or indolent, composite, and cutaneous lymphomas were excluded. The patients' medical records were retrospectively reviewed to determine the frequency and type of SI used. Of those with relapse, the method of relapse detection and data on symptoms, signs, and elevated lactate dehydrogenase LDH were extracted.

RESULTS

A total of 338 patients were included in the present study. In the first year after achieving CR1, patients had an average of 1.2 and a median of 1 SI performed (range, 0-4). In the second year after achieving CR1, they had an average of 0.78 and a median of 1 SI performed (range, 0-4). Of the 135 patients who achieved CR1, 61 (45%) developed a relapse. Relapses were detected before SI in 48 (84%), and 9 patients had relapses detected during routine SI. Of the 9 patients whose relapses were detected during planned SI, only 3 did not have any symptoms or signs suggestive of relapsed disease. Of these 3 patients, 2 had angioimmunoblastic T-cell lymphoma and 1 had natural killer/T-cell lymphoma.

CONCLUSION

Most PTCL relapses were detected before planned SI, and most patients had symptoms with relapse. Only 3 patients (5.2%) were completely asymptomatic at relapse, suggesting a limited utility of routine imaging for detecting PTCL relapses.

Mixed Phenotype Acute Leukemia with Low Hypodiploidy in a Pediatric Patient

We describe the case of a 16 year-old female with mixed phenotype acute leukemia B/myeloid, NOS (formerly biphenotypic leukemia) with masked hypodiploidy and somatic TP53 and CDKN2A/B deletions. She achieved morphologic remission with lymphoid-directed multi-agent chemotherapy, but experienced an early medullary relapse 11 months from initial diagnosis. Her case details the unusual finding of hypodiploidy in a patient with ambiguous lineage leukemia and highlights the complexity of therapy selection for these high-risk patients.

WPSS is a strong prognostic indicator for clinical outcome of allogeneic transplant for myelodysplastic syndrome in Southeast Asian patients

To better understand the predictive factors and improve clinical outcome of allogeneic transplant for patients with myelodysplastic syndrome (MDS), we retrospectively analyzed the post-transplant outcome of 60 Southeast Asian patients with MDS. Multivariate analysis showed that WHO classification-based Prognostic Scoring System (WPSS) significantly affect overall survival (OS), progression-free survival (PFS), cumulative incidence of relapse (CIR), and cumulative incidence of non-relapse mortality (CINRM). Stratified by WPSS into very low/low, intermediate, high, and very high-risk categories, 3-year OS was 100, 61, 37, and 18% (p = 0.02); PFS was 100, 55, 32, and 18% (p = 0.014); CIR was 12, 24, 38, and 59% (p = 0.024); CINRM was 0, 6, 12, and 26% (p = 0.037), respectively. WHO classification, Revised International Prognostic Scoring System (IPSS-R), IPSS-R-defined cytogenetic risk groups, donor gender, and acute and chronic graft vs host disease (GVHD) also influenced different aspects of transplant outcome. We found that WPSS is a powerful predictor of post-transplant outcome. WPSS provides an important model not only for prognostication but also for exploration of further post-transplant measures such as immunological maneuvers or novel therapy to improve the poor outcome of high-risk patients.

Pre-transplant achievement of negativity in minimal residual disease and French-American-British L1 morphology predict superior outcome after allogeneic transplant for Philadelphia chromosome positive acute lymphoblastic leukemia: an analysis of Southeast Asian patients

To better understand predictive factors and improve the clinical outcome of allogeneic transplant for patients with Philadelphia positive acute lymphoblastic leukemia, we analyzed 67 Southeast Asian patients transplanted in our institutions. Multivariate analysis showed that disease status before transplant, year of transplant and, interestingly, French-American-British (FAB) subtype had a significant impact on overall survival (OS) and non-relapse mortality. Patients who were minimal residual disease (MRD) negative at transplant had a 3-year OS of 73% compared to those who were MRD positive (45%) and refractory (0%). The 3-year cumulative incidence of relapse was 18% and 36% for the MRD negative and positive groups, respectively. FAB L1 subtype had a significantly superior 3-year OS of 63% vs. 29% for L2 subtype. Pre-transplant use of a tyrosine kinase inhibitor significantly improved outcomes in univariate but not multivariate analysis, as it served to induce more patients into MRD negativity, which was the factor that directly improved transplant outcome.

Towards a global system of vigilance and surveillance in unrelated donors of haematopoietic progenitor cells for transplantation

Safety of living donors is critical to the success of blood, tissue and organ transplantation. Structured and robust vigilance and surveillance systems exist as part of some national entities, but historically no global systems are in place to ensure conformity, harmonisation and the recognition of rare adverse events (AEs). The World Health Assembly has recently resolved to require AE/reaction (AE/R) reporting both nationally and globally. The World Marrow Donor Association (WMDA) is an international organisation promoting the safety of unrelated donors and progenitor cell products for use in haematopoietic progenitor cell (HPC) transplantation. To address this issue, we established a system for collecting, collating, analysing, distributing and reacting to serious adverse events and reactions (SAE/R) in unrelated HPC donors. The WMDA successfully instituted this reporting system with 203 SAE/R reported in 2011. The committee generated two rapid reports, reacting to specific SAE/R, resulting in practice changing policies. The system has a robust governance structure, formal feedback to the WMDA membership and transparent information flows to other agencies, specialist physicians and transplant programs and the general public.