Clinical Characteristics And Influence Factors Of Prognosis Of Infantile Spasms: Analysis Of 115 Cases

Objective: To summarize the clinical characteristics of infantile spasms and analyze the influence factor of prognosis, providing the theoretical evidence for diagnosis, treatment and prognosis judgement. Methods: The database of 115 children with infantile spasms diagnosed in hospital from 1996 to 2006 was reviewed, regarding the sex, age of onset, pattern of spasms, mental and motor development, etiology, EEG and treatment, of which 27 cases were followed up.Results:(1) A total of 115 cases had infantile spasms. The sex ratio of male:female was 1.74:1. In this study, the age of onset of infantile spasms varied from 2 days to 1 year 7 months, with a peak age ranged from 3 to 8 months(66.96%). The course of spasms lasted from 1 day to 1 year 8 months.(2) The clinical seizure patterns of infantile spasms including flexor, extensor, mixed extensor-flexor, subtle spasms and limb predominance were shown in 69.57%, 5.22%, 12.17%, 5.22% and 7.83% patients, respec- tively. Onset age of the latter two was almost little than 3 months.(3) 97 cases had mental and motor development retardation except 18 cases when taken into hospital. There was significant difference in mental and motor development between the two groups : course of spasms lasting shorter than one month and that longer than one month.(4) In this study, 51 cases had abnormal personal history. As to the neuroimaging examination, abnormal findings were found in 49 cases in CT, 35 cases in MRI respectively. The underlying causes were determined in 81 patients, including prenatal causes in 49 cases and perinatal or postnatal causes in 32 cases. 34 cases were cryptogenic. In the symptomatic group, the major underlying causes were intrauterine asphyxia, brain malformation or dysplasia, and perinatal asphyxia or intracranial hemor- rhage. There was statistically significant in the age of onset among the prenatal, perinatal or postnatal cause group and cryptogenic group.(5) In terms of EEG in 115 cases, several patterns were identified, including hypsarrhythmia (N=37;32.17%), modified hypsarrhythmia(N=58; 50.43%) and other interictal pattern (N=20;17.39%).(6) Among 58 newly diagnosed infantile spasms, 38 cases were free of spasms within 14 days after treatment. 20 cases still suffered from spasms after 14 days of treatment. There were 16 cryptogenic cases in the former and 2 cases in the latter.(7) 27 cases were followed up, in which 2 died, 13 free of seizure, and 12 still suffered from spasm or other forms of convulsion, with 7 evolved into other seizure type. As to the psychological examination, mental retardation was present in all the patients followed up: mild in 3, moderate in 9, and severe in 13.(8) Several influence factors were analyzed in relation to short term seizure control, including sex, age of onset, time lag before treatment, neurodevelopment when taken into hospital, family history of epilepsy, etiology, EEG and hormonal treatment. Only a symptomatic etiology had a positive correlation with poor short term spasm control, odds ratio=5.995.(9) The following influence factors in relation to long term prognosis were analyzed, including sex, age of onset, time lag before treatment, neurodevelopment when taken into hospital, family history of epilepsy, etiology and EEG. Only etiology was statistically significant.Conclusions:(1) The earlier age of onset was, the more atypical the clinical mani- festation was. It also represented as subtle spasms, focal seizure or clonic attack, and changed into typical spasms gradually.(2) The longer the course of spasms was, the worse the mental retar- dation was. The mental retardation appeared after one month of spasms.(3) The age of onset of infantile spasms was influenced by etiology. Onset age of the prenatal group was the earliest, followed by the crypto- genic group. And that of the perinatal or postnatal group was significantly later than the former two.(4) In the symptomatic group of infantile spasms, 81.48% of the patients were caused by intrauterine asphyxia, brain malformation or dysplasia, and perinatal asphyxia or intracranial hemorrhage. So it was necessary to strengthen health care of mother during prenatal and perinatal periods to prevent and reduce the incidence of infantile spasms.(5) The seizure control and neurodevelopment of infantile spasms of cryptogenic group were better than those of symptomatic group. The prognosis of infantile spasms depended on etiology.