title: Electrocardiographic abnormalities in patients with diphtheria: a prospective study.
abstract: OBJECTIVE
  To determine the incidence of and risk factors for electrocardiographic (ECG) abnormalities in adults with diphtheria.
  
  
  METHODS
  A prospective study was conducted involving 122 adult patients with respiratory tract diphtheria. Diphtheria was confirmed by isolation of a toxin-producing strain of Corynebacterium diphtheriae. Patients had serial clinical evaluations and ECGs for a minimum of 21 days.
  
  
  RESULTS
  Cardiac involvement was detected in 25 (28%) of 88 evaluable patients, with a median time from symptom onset to an abnormal ECG of 9 days (range, 4 to 24 days). In a logistic regression analysis, age (odds ratio [OR] = 4.1; 95% confidence interval [CI]: 1.6 to 11.0), shared accommodation (OR = 2.9; 95% CI: 1.0 to 8.6), fever (OR = 4.2; 95% CI: 1.1 to 16.6), and extensive respiratory tract infection with subcutaneous edema (OR = 7.0; 95% CI: 1.2 to 42.2) were independent risk factors for cardiac involvement.
  
  
  CONCLUSIONS
  Cardiac involvement is a common complication of respiratory tract infection with C. diphtheriae, and occurs more often among older patients, those with lower socioeconomic status, and those with severe respiratory tract involvement.
authors.affiliation: Department of Medicine, Tampere University Hospital, Tampere, Finland. jukka.lummio@pshp.fi
authors.forename: Jukka T
authors.initials: JT
authors.lastname: Lumio
authors.forename: Kaj W E
authors.initials: KW
authors.lastname: Groundstroem
authors.forename: Oleg B
authors.initials: OB
authors.lastname: Melnick
authors.forename: Heini
authors.initials: H
authors.lastname: Huhtala
authors.forename: Aza G
authors.initials: AG
authors.lastname: Rakhmanova
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D004165:Diphtheria / Q000150:complications* / Q000503:physiopathology; D004562:Electrocardiography; D005260:Female; D006331:Heart Diseases / Q000175:diagnosis / Q000209:etiology*; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011446:Prospective Studies; D012959:Socioeconomic Factors