This Article Full Text Full Text (PDF) Submit a related Letter to the Editor Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Copyright Permission Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Findling, J. W. Articles by Raff, H. Search for Related Content PubMed PubMed Citation Articles by Findling, J. W. Articles by Raff, H.

Identification of Patients with Cushing’s Disease with Negative Pituitary Adrenocorticotropin Gradients during Inferior Petrosal Sinus Sampling: Prolactin as an Index of Pituitary Venous Effluent

Endocrine-Diabetes Center (J.W.F.), Endocrine Research Laboratory (H.R.), and Department of Radiology (M.E.K.), St. Luke’s Medical Center, Milwaukee, Wisconsin 53215; and Department of Medicine (J.W.F., H.R.), Medical College of Wisconsin, Milwaukee, Wisconsin 53226

Address all correspondence and requests for reprints to: Hershel Raff, Ph.D., Endocrinology, St. Luke’s Physician’s Office Building, 2801 West Kinnickinnic River Parkway, Suite 245, Milwaukee, Wisconsin 53215. E-mail: hraff{at}mcw.edu.

Inferior petrosal sinus sampling for ACTH differentiates pituitary ACTH-dependent Cushing’s (CD) from the ectopic ACTH syndrome (EAS). Petrosal sinus to peripheral (IPS:P) ACTH ratios greater than 2.0 in the basal state or a peak greater than 3.0 after CRH are diagnostic of CD. However, false-negative rates of 1–10% have been reported. We report three patients with features of CD with peak IPS:P ACTH ratios less than 3.0 after CRH suggesting EAS. We compared IPS:P prolactin (PRL) as an index of pituitary venous effluent in these three index cases with 44 patients with CD and five with EAS. The dominant basal IPS:P PRL ratio was greater than 1.8 in all 49 patients but was less than 1.2 in the three index cases. The IPS:P ACTH ratio normalized to IPS:P PRL was greater than 0.8 in all CD patients but was less than 0.6 in EAS patients. The IPS:P ACTH ratios normalized to IPS:P PRL were greater than 1.2 in the index cases, which was similar to those with CD. The three index cases had clinical and biochemical remissions after pituitary surgery.

PRL is an index of pituitary venous effluent during inferior petrosal sinus sampling in patients with CD who fail to have a peak IPS:P ACTH ratio greater than 3.0 after CRH. IPS:P PRL should be measured when results indicate EAS.

This article has been cited by other articles:

				S. Tsagarakis, D. Vassiliadi, I. S. Kaskarelis, J. Komninos, E. Souvatzoglou, and N. Thalassinos The Application of the Combined Corticotropin-Releasing Hormone plus Desmopressin Stimulation during Petrosal Sinus Sampling Is Both Sensitive and Specific in Differentiating Patients with Cushing's Disease from Patients with the Occult Ectopic Adrenocorticotropin Syndrome J. Clin. Endocrinol. Metab., June 1, 2007; 92(6): 2080 - 2086. [Abstract] [Full Text] [PDF]

				J. W. Findling and H. Raff Cushing's Syndrome: Important Issues in Diagnosis and Management J. Clin. Endocrinol. Metab., October 1, 2006; 91(10): 3746 - 3753. [Abstract] [Full Text] [PDF]