Diphtheria pertussis tetanus vaccine induced convulsion: is hypocalcemia a triggering factor?


  • Usha Kiran C. B. Department of Pediatrics, Mysore Medical College and Research Institute, Mysore, Karnataka




Calcium, Fever, Hypothalamus, Pertusiss toxin


Background: Active pertussis toxin in diphtheria pertussis tetanus (DPT) vaccine has been proposed to cause severe reactions. A convulsion following DPT vaccine is a known adverse reaction but hypocalcemia as a triggering factor is not reported. The aim of the study was to find the association between serum calcium and DPT vaccine induced convulsions and to study the clinical profile.

Methods: Retrospective observational and descriptive study was done at emergency ward of a tertiary care teaching hospital. 20 infants of DPT induced convulsions with previous normal neurodevelopment were included in the study. Main outcome measures were association between DPT vaccine induced convulsions and serum calcium levels.

Results:Out of 20 infants included in the study, male to female ratio was 1.8:1, all of them were less than 6 months of age, 17 (85% ) were exclusively breast fed, hypocalcemia was seen in 17 cases (85%), 11 (55%) had fever. 16 (80%) had convulsions following third dose of DPT vaccine.

Conclusions:There is a significant association between hypocalcemia and DPT vaccine induced convulsion. Hence there is need for Calcium and Vitamin D3 supplementation in pregnant and lactating mothers and early detection and adequate treatment of rickets in infants. 



Blumberg DA, Lewis K, Mink CA, Christenson P D, Chatfield P, Cherry JD et al. Severe reactions associated with Diphtheria-tetanus-pertussis vaccine: detailed study of children with seizures, hypotonic-hyporesponsive episodes, high fevers and persistent crying. Pediatrics. 1993;91:1158-65.

Griffin MR, Ray WA, Mortimer EA, Fenichel GM, Schaffner W. Risk of seizures and encephalopathy after immunization with Diphtheria-tetanus-pertussis vaccine. J Am Med Asso. 1990;263:1641-5.

Cherry JD, Haltzman AE, Shields WD, Buch D, Nielsen C, Jacobsen V et al. Pertussis immunization and characteristics related to first seizures in infants and children. J Pedia. 1993;122:900-3.

Donnelly S, Loscher CE, Lynch MA, Mills KH. Whole cell but not acellular pertussis vaccine induce convulsive activity in mice: evidence of a role for toxin-induced interleukin-1 beta in a new murine model for analysis of neuronal side effects of vaccination. Infect Immun. 2001;69:4217-23.

WHO. Observed rate of vaccine reaction: Diphtheria, pertussis, tetanus vaccine. WHO;2014.

Zoethout WD, Zoethout WT. Text book of Physiology.12th ed. St Louis Mosby;1952:420-1.

John E, Guyton, Hall. Textbook of Medical Physiology. 13th ed. Philadelphia: Saunders/ Elsiever; 2010:116.






Original Research Articles