Endocrinology Flashcards
How is hypothyroidism detected on neonatal screening?
Measuring TSH - high in hypothyroidism
Causes of Rickets
Nutritional (primary)
Intestinal malabsorption of Ca: celiac disease, CF, cholestatic liver disease
Defective production of 25(OH) D3 - chronic liver disease
Chronic renal disease
Clinical features of Rickets
FTT/ short stature
Frontal bossing of skull
Craniotabes
Delayed closure of ant fontanelle
Rickety rosary - the costochondral junctions are palpable
Wrists and ankles are widened
Harrisons sulci
Bowing of weightbearing bones
Lab values in Rickets
Calcium decreased or normal
Phosphate decreased
Alkaline phosphatase very elevated
25 (OH) D3 decreased
PTH increased
1,25 (OH)2 D3 (active vit D) has three functions:
1) increase absorption of calcium from intestine
2) increase reabsorption of calcium from bones (also PTH)
3) increase reabsorption of calcium from kidneys (also PTH)
Common cause of hypoparathyroidism in childhood
Congenital deficiency - DiGeorge syndrome
Symptoms of hypocalcemia
Muscle spasms leading to tetani
Seizures
Bronchospasms
Laryngospasm - stridor
Diarrhea
Most common enzyme deficiency in CAH
21- hydroxylase deficiency
Lab values in salt-losing CAH
Very high level of 17-alpha-hydroxyprogesterone
Hyponatremia Hyperkalemia Hypoglycemia Hypotension Metabolic acidosis
Presentation of CAH in female infants
Virilization of external genitalia – ambiguous genitalia
Clitoral hypertrophy
Variable fusion of labia
Internal genitalia female
Causes of congenital hypothyroidism
Maldescent of thyroid and athyrosis
Dyshormogenesis
Iodine deficiency
