Abstract

Diphtheria continues to be reported from many parts of the world. Complete heart block is rare but often fatal complication of diphtheric myocarditis. We report six children with diphtheric myocarditis who presented with complete heart block. Three patients survived, one with persistent complete heart block. Aggressive supportive management including transvenous pacing may result in complete recovery in a significant number of children  with diphtheric myocarditis.
Material and Method: For this  study, 67 patients having diphtheria presenting for the first time in a 3 year period were enrolled after obtaining informed verbal consent from the guardian of each child. Demographical profile, vaccination status, clinical spectrum, ECG interpretation and echocardiographic findings were recorded.
Results: Among the 67 enrolled children (M: F 2.4:1) with age ranging from 24 to 172 months (median 106 months), 56.7% subjects presented with diphtheria were non-vaccinated. Almost 37.3% had a cardiac involvement in the form of diphtheria cardiomyopathy or arrhythmia. Total 7.5% patient expired on follow up. Septal paradoxes had 76% sensitivity and 100% specificity with a positive predictive value (PPV) of 100%. Nasopharyngeal membrane had a PPV of 40.4% (P=0.42). Neck swelling had a PPV of 57.9% (P=0.02). Moderate severity score of diphtheria disease had a PPV of 90% and severe disease had a PPV of 100%. Tracheostomy at presentation having a PPV of 100% (p=0.001). Presence of arrhythmia was associated with the highest mortality (Odd Ratio 18.1; 95% CI 2.7-73.9; P = 0.0001). Presence of septal paradoxes on echo had association with the cardiac involvement (OR 10.1: 95% CI 1.2-84.6; P = 0.0005)
Conclusion: Early prediction by alone or in combination of ECG and echocardiographic marker leads to early pick up of the disease and can decrease the burden of the disease in the community. Increased immunization coverage including booster dose of diphtheria and Tetanus (DT), easy availability of anti-diphtheritic serum (ADS), early prediction and recognition and effective treatment all may reduce the incidence and mortality.