Post-diphtheritic Polyneuropathy in Children with Diphtheria: A Prospective Observational Study

This study aimed to determine the proportion of diphtheria patients who develop post-diphtheritic polyneuropathy (DP) later on and also to study the clinical features and outcomes of children with post-DP. This prospective observational study was conducted at the Department of Pediatrics, King George’s Medical University, Lucknow, Uttar Pradesh, India. Children under 14 hospitalized with clinically diagnosed diphtheria and post-DP were recruited (n = 81). Detailed clinical examination with appropriate investigations was conducted, including throat swabs for staining and culture for Corynebacterium diphtheria, nerve conduction studies, electrocardiography, and echocardiography. The data were analyzed using Statistical Package for Social Sciences (SPSS) version 16.0. Seventy-four cases of diphtheria and seven cases of post-DP were enrolled, 56.8% were male, and the most prevalent age group afflicted was two to five years. Fifty-three children (65.4%) were partially immunized for diphtheria. Neck swelling, voice change, difficulty breathing, noisy breathing, respiratory involvement, and stridor were significantly more common in the unimmunized group. Voice change, heart rate irregularity, and hypotension were substantially more common in patients who developed clinical neuropathy than those who did not. Early administration of antibiotics in children with diphtheria before hospital admission was found to be significant in those children who did not develop clinical polyneuropathy, 38.5% of diphtheria survivors had abnormal nerve conduction study at six weeks of illness. Neck swelling and change in voice were significantly more common in patients with abnormal nerve conduction velocity (NCV) than in normal nerve conduction studies, 87.5% of children who had taken antibiotics before hospital admission had no clinical neuropathy, and NCV was also normal. Clinical neuropathy developed in just 20% of diphtheria patients with impaired NCV. Any child diagnosed with diphtheria should be followed for three to six months in anticipation of neurological complications. DP carries a good prognosis; hence, timely diagnosis and differentiation from other neuropathies is a prerequisite for rational management.