Frequent lower respiratory tract disease in hematological patients with parainfluenza virus type 3 infection

Human parainfluenza virus type 3 (HPIV‐3) may cause lower respiratory tract infection disease (LRTI‐D) after hematopoietic stem cell transplantation (HSCT). Most previous have studies focused on recipients of HSCT whereas data on characteristics and outcomes in patients with hematological malignancies (HMs) compared to non‐hematological patients are limited. The prognostic value of viral load in respiratory specimens remains elusive. In a 2‐year retrospective study, we determined the frequencies of LRTI‐D in HM, HSCT, and in non‐hematological patients, and HPIV‐3 levels in respiratory tract secretions. Among 98 patients with HPIV‐3 infection, including 31 HSCT and 40 HM, 36 had a diagnosis of LRTI‐D. LRTI‐D was significantly more frequent in patients with HM or HSCT (n = 32, 45.1%) than in non‐hematological patients (n = 4, 14.8%) (p = 0.006). The median HPIV‐3 loads were high in upper respiratory tract secretions regardless of the presence or absence of LRTI‐D (8.3 log10 vs. 7.6 log10 TCID50/106 cells). HPIV‐3 loads in respiratory tract samples in HM were not significantly higher than those found in HSCT but significantly higher than in non‐hematological patients (p = 0.007). In conclusion, LRTI‐D was frequent in HM patients who were diagnosed with HPIV‐3 infection.