Localized acquired hypertrichosis after cast treatment in pediatric and adolescent patients: a natural history study.

BACKGROUND: Localized acquired hypertrichosis (LAH) is a condition characterized by increased hair growth and is frequently seen after cast removal in children and adolescents. The purpose of this study was to examine the natural history of LAH and its potential impact on patients' quality of life. METHODS: Patients between the ages of 5 and 16 years, in whom hypertrichosis was detected after the removal of a cast were enrolled in a prospective study. Each patient completed the Children's Dermatology Life Quality Index after cast removal and at follow-up. Each patient was followed up until complete resolution of hypertrichosis. Statistical analyses were performed to determine any relation between the time to resolution of hypertrichosis and potential contributing variables including age, sex, initial diagnosis, type of cast, type of cast liner, and duration of cast. RESULTS: Of the 25 enrolled patients, 3 were lost during follow-up and 1 girl was excluded. The mean Children's Dermatology Life Quality Index total score was 1.1±1.4, with the majority of patients (68%) scoring 0 or 1. The hypertrichosis was completely resolved within 6 months in 17 of the 21 patients and within 6 to 12 months in the remaining 4. Although duration of cast showed a statistically significant correlation to time to resolution (P=0.008), the other variables studied showed no significant relationship. CONCLUSIONS: According to this study, LAH is typically resolved within 6 months in 80% of patients. It was not found to negatively impact the quality of life in any of the patients. The study determined that the longer the cast was applied, the longer was the time for hypertrichosis to resolve. LEVEL OF EVIDENCE: Level II, prognostic study.

Mouse behavioral tasks relevant to autism: phenotypes of 10 inbred strains.

Three defining clinical symptoms of autism are aberrant reciprocal social interactions, deficits in social communication, and repetitive behaviors, including motor stereotypies and insistence on sameness. We developed a set of behavioral tasks designed to model components of these core symptoms in mice. Male mice from 10 inbred strains were characterized in assays for sociability, preference for social novelty, and reversal of the spatial location of the reinforcer in T-maze and Morris water maze tasks. Six strains, C57BL/6J, C57L/J, DBA/2J, FVB/NJ, C3H/HeJ, and AKR/J, showed significant levels of sociability, while A/J, BALB/cByJ, BTBR T(+)tf/J, and 129S1/SvImJ mice did not. C57BL/6J, C57L/J, DBA/2J, FVB/NJ, BALB/cByJ, and BTBR T(+)tf/J showed significant preference for social novelty, while C3H/HeJ, AKR/J, A/J, and 129S1/SvImJ did not. Normal scores on relevant control measures confirmed general health and physical abilities in all strains, ruling out artifactual explanations for social deficits. Elevated plus maze scores confirmed high anxiety-like behaviors in A/J, BALB/cByJ, and 129S1/SvImJ, which could underlie components of their low social approach. Strains that showed high levels of performance on acquisition of a T-maze task were also able to reach criterion for reversal learning. On the Morris water maze task, DBA/2J, AKR/J, BTBR T(+)tf/J, and 129S1/SvImJ failed to show significant quadrant preference during the reversal probe trial. These results highlight a dissociation between social task performance and reversal learning. BTBR T(+)tf/J is a particularly interesting strain, displaying both low social approach and resistance to change in routine on the water maze, consistent with an autism-like phenotype. Our multitask strategy for modeling symptoms of autism will be useful for investigating targeted and random gene mutations, QTLs, and microarray analyses.