4 yrs old child presents with lethargy, delayed development of epiphysis, and and retarded dental eruption. He also seemed to have growth retardation and mental retardation. He also shows slow relaxation component of deep tendon reflexes. Diagnosis is:

Juvenile hypothyroidism often presents with sho stature and abnormal weight gain. Other findings include delayed epiphyseal development, delayed closure of fontanels, and retarded dental eruption. The skin may be dry, thick, scaly, coarse, pale, cool, or mottled, or have a yellowish tinge. The hair may be dry, coarse, or brittle. Lateral thinning of the eyebrows may occur. Musculoskeletal findings include hypotonia and a slow relaxation component of deep tendon reflexes (best appreciated in the ankles). Other findings include physical and mental sluggishness, nonpitting myxedema, constipation, large tongue, hypothermia, bradycardia, hoarse voice or cry, umbilical hernia, and transient deafness. Pubey may be delayed. Ref: Zeitler P.S., Travers S.H., Nadeau K., Barker J.M., Kelsey M.M., Kappy M.S. (2012). Chapter 34. Endocrine Disorders. In W.W. Hay, Jr., M.J. Levin, R.R. Deterding, J.J. Ross, J.M. Sondheimer (Eds), CURRENT Diagnosis & Treatment: Pediatrics, 21e.