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

Wang, Lin; Allen, John; Diong, Colin; Goh, Yeow‐Tee; Gopalakrishnan, Sathish; Ho, Aloysius; Hwang, William; Lim, Francesca; Oon, Lynette; Tan, Thuan‐Tong; Linn, Yeh‐Ching; Tan, Ban Hock

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.