Consensus recommendations for optimising the diagnosis and treatment of paroxysmal nocturnal haemoglobinuria in Singapore.

Introduction: Paroxysmal nocturnal haemoglobinuria (PNH) is a rare haematologic disease characterised by intravascular haemolysis, thrombophilia and bone marrow failure. There is a lack of established clinical guidance on the screening, diagnosis and manage-ment of PNH in Singapore. A relatively low level of awareness among healthcare professionals regarding PNH manifestations further contributes to diagnostic delays. Additionally, limited access to complement inhibitors, like eculizumab, may delay treatment and impact patient outcomes. Method: Nine haematologists from different institu-tions in Singapore convened to formulate evidence-based consensus recommendations for optimising the diagnosis and management of patients with PNH and improving access to novel treatments. The experts reviewed the existing literature and international guidelines published from January 2010 to July 2023, focusing on 7 clinical questions spanning PNH screening, diagnostic criteria, investigations, treatment and monitoring of subclinical and classic disease, PNH with underlying bone marrow disorders, and PNH in pregnancy. A total of 181 papers were reviewed to formulate the statements. All experts voted on the statements via 2 rounds of Delphi and convened for an expert panel discussion to finetune the recommendations. Results: Sixteen statements have been formulated for optimising the screening, diagnosis and management of PNH. Upon confirmation of PNH diagnosis, individuals with active haemolysis and/or thrombosis should be considered for anti-complement therapy, with eculizumab being the only approved drug in Singapore. Conclusion: The current recommendations aim to guide the clinicians in optimising the screening, diagnosis and management of PNH in Singapore.

Development of resilience scale for older adults.

OBJECTIVES: Older adults are more likely to encounter adverse life events and have protective factors that are different from other populations. Currently, there is no resilience scale designed exclusively for older adults. This study aims at developing a new measurement scale for assessing resilience of older adults. METHODS: Items of Resilience Scale for Older Adults (RSOA) was generated from thorough literature review. A multiple stage method was applied to examine the psychometric properties of the scale. In pretesting, items that did not meet the psychometric criteria were removed. A sample of 368 older adults was collected in the main survey to perform preliminary item selection and removal, reliability and construct validity analyses. Another survey on 76 samples was then conducted to assess test-retest reliability of the scale. RESULTS: RSOA that comprised four constructs (personal strength, meaning and purpose of life, family support, and social support) with a total of 15 items was developed with good reliability and validity. Cronbach's α of the scale was 0.882. All the four constructs were found significantly correlated with life satisfaction of older adults. CONCLUSIONS: The RSOA is a reliable means of assessing psychological and physical resilience of older people as well as predicting their satisfaction with life. The study may also provide important information about elderly coping with adversity.

Discovery of a 382-nt deletion during the early evolution of SARS-CoV-2

To date, the SARS-CoV-2 genome has been considered genetically more stable than SARS-CoV or MERS-CoV. Here we report a 382-nt deletion covering almost the entire open reading frame 8 (ORF8) of SARS-CoV-2 obtained from eight hospitalized patients in Singapore. The deletion also removes the ORF8 transcription-regulatory sequence (TRS), which in turn enhances the downstream transcription of the N gene. We also found that viruses with the deletion have been circulating for at least four weeks. During the SARS-CoV outbreak in 2003, a number of genetic variants were observed in the human population [1], and similar variation has since been observed across SARS-related CoVs in humans and bats. Overwhelmingly these viruses had mutations or deletions in ORF8, that have been associated with reduced replicative fitness of the virus [2]. This is also consistent with the observation that towards the end of the outbreak sequences obtained from human SARS cases possessed an ORF8 deletion that may be associated with host adaptation [1]. We therefore hypothesise that the major deletion revealed in this study may lead to an attenuated phenotype of SARS-CoV-2.

Long-term follow-up of Asian patients younger than 46 years with acute myeloid leukemia in first complete remission: comparison of allogeneic vs. autologous hematopoietic stem cell transplantation.

Optimal therapy for patients with acute myeloid leukemia (AML) in first complete remission (CR-1) remains the subject of debate: with the possibilities of chemotherapy alone, autologous (auto) or allogeneic (allo) hematopoietic stem cell transplantation (HSCT). We undertook a retrospective analysis of AML patients aged below 46 years and in CR-1, who had undergone auto- or allo-HSCT in our institution, to determine the factors associated with a better outcome. Between September 1985 and April 2003, 81 patients underwent autologous (n = 29) or allogeneic (n = 52) HSCT in CR-1. With a median follow-up of 10 years, the probability of 15-year overall survival (OS) was 51%[95% confidence interval (CI) = 32 - 70%] for auto-HSCT vs. 55% (95% CI = 42 - 69) for allo-HSCT, respectively (P = 0.92). The cumulative incidence of relapse at 3 years was 49% (95% CI = 30 - 67) (auto) vs. 21% (95% CI = 10 - 30) (allo), respectively. Non-relapse-related mortality at 3 years was 5% (95% CI = 0 - 14) (auto) vs. 17% (95% CI = 7 - 28) (allo), respectively. This retrospective analysis confirmed that auto- and allo-HSCT led to similar OS. The significantly lower incidence of relapse amongst allograft recipients was balanced by an increased incidence of death in CR.