BACKGROUND: Pulmonary infection is one of the life-threatening complications occurring during allogeneic hematopoietic stem cell transplantation (alloHSCT), even when prophylactic measures have been employed. Few studies have investigated whether pulmonary infection affects platelet recovery during alloHSCT.

MATERIAL AND METHODS: We retrospectively reviewed 253 consecutive patients with hematologic diseases who received alloHSCT in our institute. Among them, 62 patients (25%) had pulmonary infection within 100 days after alloHSCT. Using the one-to-two propensity-score matching logistic model, 50 patients with pulmonary infection and 100 patients without were included based on age, disease and stage, time from diagnosis to transplantation, infused CD34⁺ cells, and mononuclear cells.

RESULTS: The incidences of prolonged thrombocytopenia in patients with pulmonary infection were 44% (22/50) and 9% (9/100) in the corresponding matched group (P<0.001). The mean time for platelet engraftment in patients with and without pulmonary infection were 19.29±13.96 days and 13.94±4.12 days (P=0.012), respectively. Multivariable logistic regression showed that pulmonary infection was an independent risk factor for impaired platelet recovery (OR: 5.335, 95% CI: 2.735–10.407, P<0.001). Impaired platelet recovery was associated with shorter survival and higher treatment-related mortality.

CONCLUSIONS: Our results indicate that patients with pulmonary infection within 100 days after alloHSCT are more likely to suffer from impaired platelet recovery and have inferior long-term survival.

Keywords: Platelet Count, Blood Platelets, Hematologic Neoplasms, infections, propensity score, young adult