Table 1

Proposed "HPD" classification

Facet
Possible values

Hypothalamic-pituitary dysfunction or adaptation ("H")
H0: Normal TSH secretion, adequate to T4 level
H1: Thyrotropic insufficiency


Impaired plasma protein binding ("P")
P0: Normal binding to plasma proteins
P1: Normal binding with reduced levels of plasma proteins
P2: reduced binding to proteins within normal levels
P3: reduced binding and reduced protein levels


Reduced deiodation ("D")
D0: Normal deiodation
D1: Reduced deiodation activity

Example: H1P0D1: Thyrotropic insufficiency with reduced deiodation and normal protein binding.

Dietrich et al. BMC Endocrine Disorders 2008 8:13   doi:10.1186/1472-6823-8-13