PROLACTIN AND TSH RESPONSES TO THE IN 146 HYPOPITUITARY DWARFS

Abstract

Prolactin (PRL) and TSH were measured from 0 to 90-120 minutes after TRH 0.2 mg IV in 146 hypopituitary dwarfs : 76 with cranial radiotherapy and/or hypothalamic lesions (groupe A) and 70 without grossly detectable lesion (group B) including 14 after breech presentation and 19 isolated GH deficiency. Abnormal PRL responses, either delayed or outside the normal range, were found in 71 patients, 45 from group A (59 %) and 26 from group B (37 %). Abnormal TSH responses, delayed or outside the normal range, or in the normal range with low plasma T4, were found in 90 patients : 50 from group A (66 %) of which 26 had low T4 and 40 from group B (57 %) of which 19 had low T4. One of the responses at least was abnormal in 113 (77 %): 63 from group A (83 %) and 50 from group B (71 %), only 49 patients showing abnormal responses of both hormones. In group B, 19 patients with otherwise isolated GH deficiency and normal T4 had an abnormal response of one or two hormones. It may be concluded that 1/considering both TSH and PRL responses, TRH test is abnormal in most hypopituitary dwarfs including otherwise isolated GH deficient subjects. 2/ While the percentage of normal TSH response seems identical in the different etiological types an abnormal PRL response is more frequent in lesional hypopituitarism.