The association of fever with transfusion‐associated circulatory overload

Background Fever is described in transfusion‐associated circulatory overload (TACO), reflecting either comprehensive haemovigilance or an inflammatory pathobiology (such as congestion‐associated atheroma disruptions). Methods Hospital haemovigilance data (1/1/2010–31/12/2012) were reviewed for TACO cases (frequency and mode of referral). TACO with or without fever (TACO+F/−F) was examined for its association with patient age (as a surrogate for atheroma burden) and product age (as a surrogate for storage‐related pyrogens). Fever in allergic transfusion reactions was also compared. Results Of 972 reactions, 107 suspected cases of TACO (11%) were seen. TACO+F vs. TACO−F occurred in 42·1 vs. 57·9%, respectively. TACO+F cases were discovered in referrals to investigate either a fever (in 47·1%) or dyspnoea (in 52·9%). Among TACO+F cases, 24·4% had already been febrile, whereas 75·6% exhibited a new reaction‐associated fever. After excluding preexisting fevers, TACO+F occurred in 31·8% of TACO, compared with 8·2% of allergic reactions with fever, for an odds ratio of 5·2 (2·9–9·4 [95% CI]), P < 0·001. TACO+F/TACO−F showed no difference in median host age (69 vs. 64 years, P = 0·3), RBC age (22 days +F/−F, P = 0·9) or severity. Conclusion Transfusion‐associated circulatory overload disproportionately exhibits fever compared with allergic reactions. However, TACO+F did not associate with patient or product age, nor reflect severity. To better understand TACO+F, the fever‐congestion sequence merits attention. Further study is needed to see whether TACO+F occurs as reproducibly elsewhere, and in association with atherosclerosis in a better characterized cohort.