| Clinical Transplantation, published online 9/2005. |
|
| The low-dose (1 μg) adrenocorticotropin stimulation test in kidney
and kidney–pancreas transplant patients: a potential guideline for
steroid withdrawal |
|
| M Baz-Hecht, E Osher, T Yachnin, R Nakache, G Nakache, K Tordjman
and N Stern |
|
| Institute of Endocrinology, Metabolism and Hypertension and The Unit
of Organ Transplantation, Sackler Faculty of Medicine, Tel Aviv Sourasky
Medical Center, Tel Aviv University, Tel Aviv, Israel |
|
| Chronic steroid treatment is known to impair the hypothalamic–pituitary
adrenal axis (HPA) but the need to assess HPA function prior to withdrawal
of steroid therapy in post-transplant patients has not been uniformly
accepted. We evaluated the status of the HPA axis in 48 kidney or kidney–pancreas
transplant patients who were considered for possible discontinuation
of glucocorticoid therapy using a recently validated dynamic test of
HPA integrity, the low-dose (1 μg) adrenocorticotropin (ACTH) test.
HPA suppression was detected in 29 (60%) of the patients, four of which
had severe hypoadrenalism prohibitive of steroid withdrawal. Neither
the duration of steroid treatment nor 8:00 am serum cortisol was a
useful marker of hypoadrenalism. 8:00 am cortisol in subjects with
normal HPA reserve and subjects with partial hypoadrenalism overlapped
considerably but levels <5 μg/dL were indicative of severe hypoadrenalism.
Pre-withdrawal diagnosis of partial hypoadrenalism allowed the identification
of subjects requiring no further steroid replacement under regular
daily circumstances. However glucocorticoid supplementation was prescribed
in the event of stress such as infection, exceptional effort, trauma
or surgery. Individuals with partial HPA impairment, but not patients
with severe HPA suppression, improved upon retesting 3 months later.
Patients exhibiting normal response to 1 mcg ACTH enjoyed an uneventful
course following steroid withdrawal. Since hypoadrenalism is extremely
common in post-transplant patients, we recommend the use of the low-dose
ACTH test as a convenient method to identify patients with various
degrees of hypoadrenalism prior to steroid withdrawal. |
