A follow-up study of 18 infants and children who suffered convulsions (9 cases) or “hypotonic-hyporesponsive“ episodes (9 cases) within 48 hours following DTP immunization was conducted in the Depts of Pediatrics, UCLA Hospital and Clinics, and the Kaiser Permanente Medical Group, Los Angeles, CA. After an interval of 6 to 7 years, of 16 children contacted and considered normal by the parents, 2 had delayed language or a speech problem, 1 was a grade behind in school, 1 was hyperactive and required dexedrine, 4 (31%) of 13 tested had minor neurological abnormalities, 6 (46%) had full-scale IQ scores below 90, and 7 (54%) had below average verbal IQ scores that the authors explained by the proportion of Hispanic and bilingual children in the sample. It was concluded that none of the 16 children suffered any serious neurologic damage as a result of either convulsions or “hypotonic-hyporesponsive episodes related to prior DTP immunizations. [1]

COMMENT. A previous study quoted in the article failed to demonstrate IQ deficits following febrile seizures [2]. The low IQ scores recorded at follow-up in approximately 50% of the children with seizures related to DTP immunization might suggest a febrile seizure of the complex type with residual brain pathology. This possibility was discounted because the present study population included 7 (44%) Hispanic and 3 (19%) bilingual children, although all spoke English at school.