A case of myhre syndrome with a very rare finding: Severe constipation

Myhre syndrome is an extremely rare connective tissue disorder, described by intellectual disability, fibrosis (thickening

and scarring of connective tissue), characteristic facial features (blepharophimosis, short philtrum, thin lips, maxillary

hypoplasia and prognathism), striking muscular build and typical skeletal anomalies (short stature, limited range of joint

motion, broad ribs, iliac hypoplasia, brachydactyly, platyspondyly and thickened calvarium). Additional findings are

congenital heart defects, restrictive pulmonary disease, gastrointestinal abnormalities (pyloric stenosis, duodenal

strictures), severe constipation, autistic-like behaviors and hearing loss. This syndrome was first defined by Myhre at al.

in 1981 in two unrelated males with intellectual disability, short stature, a skeletal muscular hypertrophy, decreased

joint mobility and mixed hearing loss. To date, more than 60 individuals have been reported to the medical literature.

Myhre syndrome, inherited in an autosomal dominant manner, occurs sporadically. In majority of cases, de novo

mutation in the SMAD4 gene cause this disorder. We presented a 13-year-old boy who had short stature, mild

intellectual disability, dysmorphic facial features (short palpebral fissures, deeply set eyes, maxillary hypoplasia,

prognathism, short philtrum with downturned nasal tip and small ears), short neck, brachydactyly, 2-3 syndactyly,

muscular build and thickened skin. He had also congenital heart defect and digestive problems such as severe

constipation. In patient, next generation sequence analysis revealed a recurrent p.Ile500Val mutation in the SMAD4

gene. Here, we present a rare finding: severe constipation in a patient with Myhre syndrome due to a heterozygous

mutation in the SMAD4 gene.