To compare and analyze the clinical characteristics of children with delayed language acquisition due to two different diagnoses, which were specific language impairment (SLI, a primarily delayed language development) and global developmental delay (GDD, a language delay related to cognitive impairment).

Among 1,598 children who had visited the developmental delay clinic from March 2005 to February 2011, 467 children who were diagnosed with GDD and 183 children who were diagnosed with SLI were included in this study. All children were questioned about past, family, and developmental history, and their language competences and cognitive function were assessed. Some children got electroencephalography (EEG), in case of need.

The presence of the perinatal risk factors showed no difference in two groups. In the children with GDD, they had more delayed acquisition of independent walking and more frequent EEG abnormalities compared with the children with SLI (p<0.01). The positive family history of delayed language development was more prevalent in children with SLI (p<0.01). In areas of language ability, the quotient of receptive language and expressive language did not show any meaningful statistical differences between the two groups. Analyzing in each group, the receptive language quotient was higher than expressive language quotient in both group (p<0.01). In the GDD group, the Bayley Scales of Infant Development II (BSID-II) showed a marked low mental and motor quotient while the Wechsler Intelligence Scale showed low verbal and nonverbal IQ. In the SLI group, the BSID-II and Wechsler Intelligence Scale showed low scores in mental area and verbal IQ but sparing motor area and nonverbal IQ.

The linguistic profiles of children with language delay could not differentiate between SLI and GDD. The clinicians needed to be aware of these developmental issues, and history taking and clinical evaluation, including cognitive assessment, could be helpful to diagnose adequately and set the treatment plan for each child.

To identify the clinical characteristics and investigate function related aspects of Korean children with Rett syndrome.

A total of 26 patients diagnosed as Rett syndrome were clinically observed until the age of five or over. We surveyed past history, developmental history, and presence of typical clinical features of Rett syndrome. Furthermore, we investigated differences in clinical characteristics according to functional status and changes in clinical features related to growth.

There were no problems related to gestational, perinatal or neonatal history. Only 12 patients had an ultimate head circumference of less than 3 percentile. Developmental regression was definite in all patients. At final assessment, only 14 patients were able to walk. Twenty patients had an epileptic history requiring medication. Sixteen patients with scoliosis showed progression during serial follow-up. The percentage of patients who were able to walk before 16 months was higher in the high function group than the low function group. The age of regression was 5.4 and 4.0 years in the high and low function group respectively, but the difference was not statistically significant. Scoliosis was more severe and seizure onset age was younger in the low function group.

We investigated 26 clinical characteristics in Korean children with Rett syndrome. Their clinical features change according to age, and we believe such knowledge could be utilized in rehabilitation to minimize their disabilities.

To perform an in depth evaluation of children, and thus provide a systematic method of managing children, who after infantile health screening, were categorized as suspected developmental delay.

78 children referred to the Developmental Delay Clinic of Ilsan Hospital after suspected development delay on infantile health examinations were enrolled. A team comprised of a physiatrist, pediatrician and pediatric psychiatrist examined the patients. Neurological examination, speech and cognitive evaluation were done. Hearing tests and chromosome studies were performed when needed clinically. All referred children completed K-ASQ questionnaires. Final diagnoses were categorized into specific language impairment (SLI), global developmental delay (GDD), intellectual disability (ID), cerebral palsy (CP), motor developmental delay (MD) or autism spectrum disorder (ASD).

72 of the 78 patients were abnormal in the final diagnosis, with a positive predictive value of 92.3%. Thirty (38.4%) of the 78 subjects were diagnosed as GDD, 28 (35.8%) as SLI, 5 (6.4%) as ASD, 9 (12.5%) as MD, and 6 (7.6%) as normal. Forty five of the 78 patients had risk factors related to development, and 18 had a positive family history for developmental delay and/or autistic disorders. The mean number of abnormal domains on the K-ASQ questionnaires were 3.6 for ASD, 2.7 for GDD, 1.8 for SLI and 0.6 for MD. Differences between these numbers were statistically significant (p<0.05).

Because of the high predictive value of the K-ASQ, a detailed evaluation is necessary for children suspected of developmental delay in an infantile health promotion system.