Itself a prefixed noun, "para-thyroid" attracts prefixes, single or multiple, to designate various disorders—not all of them involving the parathyroid gland. Although hyper- or. hypo-parathyroidism clearly implies that the gland is either over- or under-functioning, "pseudo-hypo-parathyroidism" shifts the responsibility for manifestations of apparent hypo-parathyroidism to the renal tubule, which fails to respond to the phosphoruretic action of parathyroid hormone. And contradicting the mathematical principle that two negatives equal a positive, "pseudo-pseudo-hypo-parathyroidism" denotes not hypo-parathyroidism, but a variant of pseudo-hypoparathyroidism in which characteristic bone changes are absent.
Defying another principle—Aristotle's law of the excluded middle, also known as the principle of contradiction—is the paradoxical "hypo-hyper-parathyroidism." Introduced by Costello and Dent1 in 1963, when they reported a coexisting manifestation of both diminished and increased parathyroid function in a 15-year-old girl, this nearly forgotten term has been recently revived by Watson2 in his follow-up on the same patient, and in his