Pseudohypoparathyroidism (PHP) is a genetic disorder of end-organ insensitivity to the effect of PTH, which results in hypocalcemia, hyperphosphatemia, and increased PTH levels
Symptoms & Signs 

-As the name implies, patients with pseudohypoparathyroidism have signs and symptoms characteristic of hypoparathyroidism

-PHP may be associated by a characteristic phenotype known as Albright Hereditary Osteodystrophy (AHO) which includes short stature, round facies, shortening of the fourth metacarpals (brachydactyly), and osteoma cutis 

-Examination of the clenched fist reveals a characteristic depression where the knuckle of the fourth metacarpal should be located.


-A high concentration of serum PTH, low serum calcium, high phosphate, and 

signs and symptoms of hypoparathyroidism

-patients with pseudohypoparathyroidism do not respond to infused PTH


Treatment is the same as for hypoparathyroidism



-The four parathyroid glands produce and secrete PTH

-Hypoparathyroidism develops when the parathyroid glands fail to secrete sufficient quantities of PTH, resulting in a low calcium level and a high phosphorus level 

-The most common cause of hypoparathyroidism is neck surgery with removal or destruction of the parathyroid glands

-Other causes include congenital abnormalities of the third and fourth pharyngeal pouches (DiGeorge syndrome), autoimmune or drug induced or radiation induced hypothyroidism 

Symptoms & Signs 

Skin: Dry, scaly skin, coarse hair

Ocular: Cataracts, Papilledema 

Dental: enamel hypoplasia, defective root formation, delayed teeth eruption

Respiratory: Bronchospasm, laryngospasm, stridor 

Cardiac: Heart failure, Prolonged QT interval on ECG

Psychological: Confusion, behavioral changes, psychosis 

Neuromuscular: numbness, tingling, carpopedal spasms, seizures, Parkinsonism

Tetany: Spontaneous tonic muscular contractions; Classically diagnosed by Chvostek sign and Trousseau sign

Chvostek sign: twitching or contraction of the facial muscles in response to tapping the facial nerve at a point anterior to the ear and above the zygomatic bone

Trousseau sign: it is elicited by inflating the sphygmomanometer with the cuff around the arm above the systolic blood pressure for 3 min; The wrist and metacarpophalangeal joints flex, the DIP and PIP joints extend, and the fingers adduct


Labs: Inappropriately low or undetectable PTH level, low calcium level, high phosphorus level

EKG: a prolonged QT interval on the ECG


Recombinant PTH; IV or oral calcium, Vitamin D supplementation; correction of hypomagnesemia