Todd B. Nippoldt

Adrenal Hemorrhage: A 25-Year Experience at the Mayo Clinic

OBJECTIVE To characterize the clinical course of adrenal hemorrhage (AH) by using a systematic review of the presentation, associated conditions, and outcomes in patients with AH seen at our institution between 1972 and 1997 (a 25-year period). PATIENTS AND METHODS A computer search of recorded dismissal diagnoses identified 204 patients with a diagnosis of AH, but only 141 fulfilled our study criteria. Their records were analyzed systematically by presentation, bilateral or unilateral hemorrhage, corticosteroid treatment, and survival. RESULTS AH is a heterogeneous entity that occurs in the postoperative period, in the antiphospholipid-antibody syndrome, in heparin-associated thrombocytopenia, or in the setting of severe physical stress and multiorgan failure. Standard laboratory evaluation is not helpful in establishing the diagnosis. Of the 141 cases of AH, 78 were bilateral, and 63 were unilateral. Corticosteroid treatment in situations of severe stress or sepsis had little effect on outcome (9% vs. 6% survival with and without corticosteroid treatment, respectively). This is in sharp contrast to AH occurring postoperatively (100% vs. 17% survival with or without treatment, respectively) or in the antiphospholipid-antibody syndrome (73% vs. 0% survival, respectively). CONCLUSIONS A high index of suspicion is required to make a timely diagnosis of AH. Fever and hypotension in the appropriate clinical setting necessitate further investigation. Although the diagnosis of AH is infrequently made while the patient is alive, appropriate imaging techniques are useful for establishing a timely diagnosis. In severe physical stress or sepsis, AH may be a marker of severe, preterminal physiologic stress and poor outcome.

Preliminary Comparison of the Endoscopic Transnasal vs the Sublabial Transseptal Approach for Clinically Nonfunctioning Pituitary Macroadenomas

OBJECTIVE To assess the advantages and disadvantages of an endoscopic transnasal approach to pituitary surgery for a select group of clinically nonfunctioning macroadenomas and to compare results of this approach with the sublabial transseptal approach at a single institution. PATIENTS AND METHODS We retrospectively reviewed the records of 26 patients with clinically nonfunctioning pituitary macroadenomas approached endoscopically and 44 matched control patients with the same tumors approached sublabially between January 1, 1995, and October 31, 1997. RESULTS At baseline, the groups were not significantly different for age, sex distribution, number of comorbid conditions, visual field defects, degree of anterior pituitary insufficiency, or preoperative assessment of tumor volume or invasiveness. Mean (SD) operative times were significantly reduced in the endoscopic group vs the sublabial group: 2.7 (0.7) hours vs 3.4 (0.9) hours (P < .001). Postoperative assessment of surgical resection and postoperative alterations of anterior pituitary function or visual fields were not significantly different between groups, and complication rates were similar in both groups. CONCLUSION This endoscopic transnasal approach to pituitary resection results in significantly shorter operative time without compromising the extent of tumor resection. The distinct disadvantage of this approach is an off-center view of the sella and a diminished working channel to the sella turcica. For these reasons, the endoscopic approach or its variation is an alternative to the sublabial approach but should be considered only by experienced pituitary neurosurgeons.

Insulin-like growth factor system abnormalities in hepatitis C-associated osteosclerosis. Potential insights into increasing bone mass in adults.

Hepatitis C-associated osteosclerosis (HCAO) is a rare disorder characterized by a marked increase in bone mass during adult life. Despite the rarity of HCAO, understanding the mediator(s) of the skeletal disease is of great interest. The IGFs-I and -II have potent anabolic effects on bone, and alterations in the IGFs and/or IGF-binding proteins (IGFBPs) could be responsible for the increase in bone formation in this disorder. Thus, we assayed sera from seven cases of HCAO for IGF-I, IGF-II, IGF-IIE (an IGF-II precursor), and IGFBPs. The distribution of the serum IGFs and IGFBPs between their ternary ( approximately 150 kD) and binary (approximately 50 kD) complexes was also determined to assess IGF bioavailability. HCAO patients had normal serum levels of IGF-I and -II, but had markedly elevated levels of IGF-IIE. Of the IGFBPs, an increase in IGFBP-2 was unique to these patients and was not found in control hepatitis C or hepatitis B patients. IGF-I and -II in sera from patients with HCAO were carried, as in the case of sera from control subjects, bound to IGFBP-3 in the approximately 150-kD complex, which is retained in the circulation. However, IGF-IIE was predominantly in the approximately 50-kD complex in association with IGFBP-2; this complex can cross the capillary barrier and access target tissues. In vitro, we found that IGF-II enhanced by over threefold IGFBP-2 binding to extracellular matrix produced by human osteoblasts and that in an extracellular matrix-rich environment, the IGF-II/IGFBP-2 complex was as effective as IGF-II alone in stimulating human osteoblast proliferation. Thus, IGFBP-2 may facilitate the targeting of IGFs, and in particular IGF-IIE, to skeletal tissue in HCAO patients, with a subsequent stimulation by IGFs of osteoblast function. Our findings in HCAO suggest a possible means to increase bone mass in patients with osteoporosis.

AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS MEDICAL GUIDELINES FOR CLINICAL PRACTICE FOR THE DIAGNOSIS AND TREATMENT OF ACROMEGALY

ENDOCRINE PRACTICE Vol 10 No. 3 May/June 2004 213 American Association of Clinical Endocrinologists Medical Guidelines for Clinical Practice are systematically developed statements to assist health-care professionals in medical decision making for specific clinical conditions. Most of the content herein is based on literature reviews. In areas of uncertainty, professional judgment was applied. These guidelines are a working document that reflects the state of the field at the time of publication. Because rapid changes in this area are expected, periodic revisions are inevitable. We encourage medical professionals to use this information in conjunction with their best clinical judgment. The presented recommendations may not be appropriate in all situations. Any decision by practitioners to apply these guidelines must be made in light of local resources and individual patient circumstances.

Neurophysiologic studies in Morvan syndrome

This study was conducted to clarify the clinical and neurophysiologic characteristics of patients with Morvan syndrome, and to compare and contrast this syndrome with other forms of autoimmune encephalitis. A retrospective chart review of the clinical features and neurophysiologic studies of two cases of Morvan syndrome seen at the Mayo Clinic was performed. Neurophysiologic studies included polysomnography, comprehensive autonomic testing, MRI, positron emission tomography, EEG, and single-photon emission computed tomography. In two cases of Morvan syndrome, the clinical features, electrophysiologic findings, and immunologic studies (high levels of voltage-gated potassium channel antibodies) were consistent with previously reported findings. Several novel observations were made. Autonomic testing demonstrated peripheral autonomic neuropathy in addition to autonomic hyperactivity. Polysomnography showed complete absence of sleep. Neuroimaging study findings were largely normal. Morvan syndrome is an autoimmune disorder affecting both the peripheral and central nervous system. Neurophysiologic studies demonstrate hyperexcitability of peripheral nerves, autonomic dysfunction, and severe insomnia. The absence of abnormalities on imaging studies suggests that central nervous system symptoms are related to functional rather than structural disruption of neural networks.

Surgery for Cushing’s Syndrome: An Historical Review and Recent Ten-year Experience

BackgroundCushing’s syndrome (CS), due to multiple etiologies, is a disorder associated with the ravages of cortisol excess. The purpose of this review article is to provide a historical synopsis of surgery for CS, review a recent 10-year period of operative management at a tertiary care facility, and to outline a practical approach to diagnosis and management.Materials and MethodsFrom 1996 to 2005, 298 patients underwent 322 operative procedures for CS at Mayo Clinic, Rochester, Minnesota. A retrospective chart review was carried out. Data was gathered regarding demographics, preoperative assessment, procedures performed, and outcomes. Data are presented as counts and percentages. Five-year survival rates were calculated where applicable by the Kaplan-Meier method. Statistical analysis was carried out with SAS, version 9 (SAS Institute, Inc., Cary, NC).ResultsTwo-hundred thirty-one patients (78%) had ACTH-dependent CS and 67 patients (22%) had ACTH-independent CS. One-hundred ninety-six patients (66%) had pituitary-dependent CS and 35 patients (12%) had ectopic ACTH syndrome. Fifty-four patients (18%) had cortisol-secreting adenomas, 10 patients (3%) had cortisol-producing adrenocortical carcinomas, and 1% had other causes. Cure rates for first time pituitary operations (transsphenoidal, sublabial, and endonasal) were 80% and 55% for reoperations. Most benign adrenal processes could be managed laparoscopically. Five-year survival rates (all causes) were 90%, 51%, and 23% for adrenocortical adenomas, ectopic ACTH syndrome, and adrenocortical carcinomas, respectively.ConclusionsSurgery for CS is highly successful for pituitary-dependent CS and most ACTH-independent adrenal causes. Bilateral total adrenalectomy can also provide effective palliation from the ravages of hypercortisolism in patients with ectopic ACTH syndrome and for those who have failed transsphenoidal surgery. Unfortunately, to date, adrenocortical carcinomas are rarely cured. Future successes with this disease will likely depend on a better understanding of tumor biology, more effective adjuvant therapies and earlier detection. Clearly, IPSS, advances in cross-sectional imaging, along with developments in transsphenoidal and laparoscopic surgery, have had the greatest impact on today’s management of the complex patient with CS.

Pituitary tumor type affects the chance of biochemical remission after radiosurgery of hormone-secreting pituitary adenomas.

OBJECTIVE Reported biochemical remission rates have ranged widely after stereotactic radiosurgery for patients with hormone-secreting pituitary adenomas. Confounding variables include histology, radiation dose, use of pituitary-suppressive medications, and length of follow-up. METHODS A retrospective review of 46 patients with pituitary adenomas (growth hormone-secreting, n = 27; prolactin-secreting, n = 11; adrenocorticotropin-secreting, n = 8) undergoing radiosurgery between January 1990 and December 2003 was conducted. All received a tumor margin dose of 18 Gy or more and were off pituitary-suppressive medications for at least 1 month before radiosurgery. The groups were similar with regard to irradiated volume, radiation dose, and follow-up. The median endocrinological follow-up after radiosurgery was 54 months. RESULTS The 4-year remission rates were 87% for patients with Cushings disease, 67% for patients with acromegaly, and 18% for patients with prolactinomas. Patients with oversecretion of adrenocorticotropin or growth hormone were more likely to achieve remission after radiosurgery than patients with prolactinomas (hazard ratio, 4.4; 95% confidence interval, 1.1-18.2; P = 0.04). Of 44 patients with normal or partial anterior pituitary function before radiosurgery, 16 (36%) developed one or more new anterior pituitary deficits. The incidence of new anterior pituitary deficits was 26% at 4 years. No differences were noted in the incidence of new anterior deficits among the groups. CONCLUSION There seems to be a differential sensitivity after radiosurgery for hormone-secreting pituitary adenomas. Remission rates are greater for patients with Cushings disease and acromegaly, whereas radiosurgery is less effective in achieving biochemical remission for patients with prolactinomas.

Factors Associated With Endocrine Deficits After Stereotactic Radiosurgery of Pituitary Adenomas

OBJECTIVETo analyze the factors associated with anterior pituitary deficits after pituitary adenoma stereotactic radiosurgery (SRS). METHODSThe tumor, pituitary stalk, and pituitary gland were segmented on the dose plans of 82 patients (secreting tumors, n = 53; nonsecreting tumors, n = 29) for dose-volume analysis. No patient had undergone prior radiation therapy and all patients had at least 12 months of endocrinological follow-up (median, 63 months; mean, 69 months; range, 13–134). RESULTSThirty-four patients (41%) developed new anterior pituitary deficits at a median of 32 months (range, 2–118) after SRS. The risk of developing new anterior pituitary deficits was 16% and 45% at 2 and 5 years, respectively. Multivariate analysis of the entire group showed that poor visualization of the pituitary gland (hazard ratio [HR] = 2.63, 95% confidence interval [CI] = 1.10–6.25, P = .03) was associated with a higher rate of new anterior pituitary deficits. Dosimetric analysis of 60 patients whose pituitary gland could be clearly identified showed that increasing mean pituitary gland radiation dose correlated with new anterior pituitary deficits (HR = 1.11, 95% CI = 1.02–1.20, P = .02). New anterior pituitary deficits stratified by mean pituitary gland radiation dose: ≤7.5 Gy, 0% (0/7); 7.6 to 13.2 Gy, 29% (7/24); 13.3 to 19.1 Gy, 39% (9/23); >19.1 Gy, 83% (5/6). CONCLUSIONNew endocrine deficits after pituitary adenoma radiosurgery were correlated with increasing radiation dose to the pituitary gland. Methods that limit the radiation dose to the pituitary gland during SRS may increase the probability of preserving pituitary function.

Effect of Growth Hormone Replacement on BMD in Adult-Onset Growth Hormone Deficiency

To determine if replacement of GH improves BMD in adult‐onset GHD, we administered GH in physiologic amounts to men and women with GHD. GH replacement significantly increased spine BMD in the men by 3.8%.

Impulse control disorders in patients with dopamine agonist‐treated prolactinomas and nonfunctioning pituitary adenomas: a case–control study

We aimed to assess the prevalence of impulse control disorders (ICDs) in patients with prolactin‐secreting adenomas treated with dopamine agonists (DAs), to identify associated factors and to compare it with a group of patients with nonfunctioning pituitary adenoma.