Demographic characteristics and ECG and laboratory findings of patients with scrub typhus admitted to Chosun University Hospital and normal subjects visiting the hospital for health check-ups from January 2008 to December 2012 were retrospectively studied.
ECG abnormalities at admission were observed in 76 (43.2%) of 176 patients with confirmed scrub typhus. The following ECG abnormalities were observed: long QT interval (34 cases, 19.3%); ischemia, including ST-segment changes, abnormal Q waves, and poor R progression (26 cases, 14.8%); arrhythmia [22 cases, 12.5%; this group included atrial fibrillation (Af) (16 cases, 9.1%), atrial premature contraction (5 cases, 2.8%) and premature ventricular complex (1 case, 0.6%)]; and conduction changes, including atrioventricular (AV) block, right bundle branch block (RBBB), and left bundle branch block (LBBB) (12 cases; 6.8%). Compared with the age- and sex-matched control group, ECG abnormalities were significantly more common among scrub typhus patients (43.6% vs. 13.9%, p<0.001). Abnormal laboratory findings were significantly more common in patients with scrub typhus in the abnormal ECG group, which showed a significantly higher severity score than the normal ECG group (6.47 vs. 5.05, p=0.001); abnormal ECG findings were also correlated with increased disease severity.
ECG abnormalities were more common in patients with scrub typhus than in the general population and were associated with more severe disease. As QT prolongation occurs in approximately 20% of patients with scrub typhus, clinicians should pay additional attention to drugs that affect QT prolongation.
D. M. Kim,
H. Sul, None
C. M. Kim, None