Diphtheria in Children- A Clinical Profile of Cases during an Outbreak in Kerala, India

Introduction: Diphtheria is an acute potentially fatal infectious disease caused by the toxigenic strains of Corynebacterium diphtheriae. Acute respiratory obstruction, toxic myocarditis and neurologic weakness are the most important complications of diphtheria. The clinical presentation and severity of diphtheria vary in immunized and non-immunized children. Early diagnosis and prompt treatment including administration of diphtheria antitoxin and antibiotics minimize mortality. Aim: To observe the changing trends in the clinical presentation of diphtheria during the 2016 outbreak and its association with immunization status and antitoxin administration. Materials and Methods: This Longitudinal prospective study conducted among children admitted to Government Medical College, Kozhikode, Kerala, a tertiary care centre with a diagnosis of diphtheria during January 2016 to December 2016. Details of socio-demographic data, clinical presentation, investigations, immunization status, treatment and complications were collected using a semi-structured performa. These children were managed by an interim guideline provided by the state authorities. They were followed-up for 3 months. The data was analyzed using Statistical Package for Social Sciences (SPSS), version 18.0. Results: Among 76 children, 62(82%) were from Malappuram and Kozhikode districts, which have relatively low immunization coverage. Most admissions were in July 2016. Majority (58, 76.3%) of children belonged to Muslim community. The mean age was 8.1 years with male to female ratio 1.53:1. Most of the children (47, 62%) were unimmunized or partially immunized. Cultures were positive for C. diphtheriae in 20 children. Complications were noted in 36 children, which included asymptomatic myocarditis in 31, symptomatic myocarditis in one, palatal palsy in nine, loss of accommodation in four and distal weakness in five. Only one child who received antitoxin within 72 hours of disease onset developed neurological complications. Complications were common in children who received less than minimum three doses of diphtheria vaccines compared to those who received three or more doses (54% vs. 44%). There was no mortality. Conclusion: There was an upward shift in age of affected children. Neurological complications were significantly less in those who received antitoxin within 72 hours of disease onset. Regular monitoring helped to detect asymptomatic myocarditis. The outbreak highlighted the need to improve a