Subclinical but significant? Updated review of pediatric hypothyroidism.

The rate of true hypothyroidism requiring treatment among children with elevated TSH referred to pediatric endocrinology ranged widely from 6.3 to 59%.

• Five studies met inclusion criteria and were analyzed from an initial search of 211 articles across four databases.
• Study population consisted of children ages 1-18 years without an underlying risk for hypothyroidism.
• The wide range (6.3-59%) indicates substantial variability across study populations and settings.
• The review focused on children referred to pediatric endocrinology with elevated TSH values.

Three key risk factors were identified as associated with developing hypothyroidism requiring treatment: TSH >10 mIU/L, presence of goiter, and positive anti-thyroid antibodies.

• TSH >10 mIU/L was identified as a significant risk factor for true thyroid disease.
• Goiter presence was identified as a clinical risk factor.
• Anti-thyroid antibodies were identified as a laboratory risk factor.
• These risk factors were derived from analysis of five studies meeting inclusion criteria.
• These findings are intended to guide practitioners about when to refer to endocrinology.

A TSH threshold of 9.6 mIU/L was identified as a high-risk value associated with thyroid disease when averaged among four studies.

• The 9.6 mIU/L threshold represents an average across four of the five included studies.
• This threshold is intended to help guide decisions about referral to pediatric endocrinology.
• The threshold is meant to assist practitioners in determining when to repeat TSH before considering referral.
• The value also helps practitioners anticipate the need for thyroid hormone replacement.

A systematic literature search of four databases identified 211 articles regarding TSH values in healthy children, of which five studies met the inclusion criteria.

• Inclusion criteria required studies on children ages 1-18 years.
• Studies were required to involve children without an underlying risk for hypothyroidism.
• The search was conducted across four databases.
• Only five of 211 articles met the full inclusion criteria for analysis.

The review findings are intended to guide clinical decision-making regarding TSH repeat testing, endocrinology referral timing, and anticipation of thyroid hormone replacement need.

• The results address when to repeat TSH value before considering referral to endocrinology.
• The findings provide guidance on when to refer patients to endocrinology.
• The data help practitioners anticipate when thyroid hormone replacement will be needed.
• The review addresses subclinical hypothyroidism, which the authors characterize as 'subclinical but significant' in the pediatric population.