GROWTH-HORMONE NEUROSECRETORY DYSFUNCTION ASSOCIATED WITH RING CHROMOSOME-18

The patient was a girl 5 years and 1 month old of markedly short statu re (-3,9 SD) for her chronological age. Although her karyotype was 46, XX, r(18)(p11q23), there were no symptoms of a chromosomal deletion. Other authors have described cases with a ring autosome showing a phen otype with short stature alone as 'ring syndrome', regardless of which autosome is involved, The present case seems to fall into this catego ry. Although blood growth hormone (GH) showed normal responses to four types of provacative tests, the mean value of blood GH levels obtaine d at 30 min intervals for 24 h was low, indicating the existence of gr owth hormone neurosecretory dysfunction (GHND).