Pituitary Function and Growth Hormone Dynamics in Acromegaloidism Robert B. Mims, MD Los Angeles, California

Acromegaloidism is a condition which resembles acromegaly by its clinical manifestations but is not due to pituitary or hypothalamic dysfunction. Twenty patients were diagnosed as having this disorder and the results from studying growth hormone (GH) responses in 15 patients (11 women and four men) were included in this report. Clinical manifestations closely resembled those ofacromegalics, including history of progressive changes, acral enlargement, visual disturbances, abnormal visual fields in four patients, and sella turcica enlargement in two patients. The glucose tolerance test (GTT) was abnormal in 12/15 patients, 13/15 were > 10 percent obese, 8/15 had hypertension, 7/15 had large-statured relatives, but lactorrhea was absent in all patients. The mean serum GH concentration was 2.2 ng/ml, which suppressed to 0.6 ng/ml during the GTT; increased to 24 ng/ml during hypoglycemia; and increased to 10.3 ng/ml after L-dopa ingestion. Other pituitary hormones (LH, FSH, TSH, prolactin), the metyrapone test, 24-hour random and nocturnal sleeping GH concentrations were normal. These GH values and responses helped to differentiate acromegaloidism from treated and untreated acromegaly. The pathogenesis of acromegaloidism was not determined, but somatomedin studies may prove helpful in further defining this disorder. Acromegaloidism is defined' as "a bodily condition resembling acromegaly but not due to a pituitary disorder." It may be confused with mild or early acromegaly on a clinical basis, especially since many acromegalic patients present for evaluation without classical signs and symptoms. Also, one must frequently evaluate patients who have been classified as having "burnt-out acromegaly," or those who have had therapy for a pituitary disorder in the past. Thus, pituitary function and growth hormone dynamics were studied in 15 patients referred for evaluation of acromegaly, but instead had acromegaloidism. Results obtained from studying these patients are the subject of this report.

Materials and Methods Eight of the 15 subjects were admitted to the Clinical Research Center for From the University of Southern California School of Medicine and the Los Angeles County-University of Southern California Medical Center, 1200 North State Street, Los Angeles, California 90033. Requests for reprints should be addressed to Dr. Robert B. Mims, 1150 Montgomery Drive, Santa Rosa, CA 95405.

the durations of these studies and informed consents were obtained before investigation. The other seven subjects were evaluated in the Department of Internal Medicine after regular hospital consents, but the tests were analyzed in the Clinical Research Center. All subjects received regular hospital diets, fluid ad libitum, and could ambulate within the unit when tests were not being done. Anti-cubital blood samples were obtained through a heparinized, indwelling, # 19 butterfly infusion set, promptly processed, and serum aliquots stored at -lOC until assay. Patients ranged in age from 17 to 67 years, and 11/15 were women. Details of the standard oral glucose tolerance test (GTT) for growth hormone suppression, insulin induced hypoglycemia, 1.0 gm L-dopa test, 24hour random growth hormone sampling, nocturnal growth hormone sampling, and diagnostic criteria for acromegaly have previously been described.2 Lutenizing hormone (LH), follicle stimulating hormone (FSH), thyrotrophin stimulating hormone (TSH), prolactin (PRL), and growth hormone (GH) were analyzed by

JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION, VOL. 70, NO. 12, 1978

radioimmunoassay, and serum cortisol and glucose by methods previously described.3 The percentage of obesity was calculated from body weights and heights, allowing 100 lb for 5 feet, plus 5 lb for each additional inch of height in women; 110 lb for 5 feet, plus 5 lb for each additional inch of height in men.

Clinical Manifestations in Patients With Acromegaloidism Table 1 shows the clinical manifestations noted in the 15 patients with acromegaloidism. Eleven patients were women and four were men; seven were white, five were black, two were Mexican-American, and one was Filipino. There ages ranged from 17 to 67 years, but 11/15 patients were over age 40. Acral enlargement and coarse facial features had been present from a few months up to about ten years. Headaches were noticeable in seven patients and considered very severe by one patient. Arthralgias, hyperhidrosis, hypertrichosis, paraesthesias, fatigue, and weakness were present in several patients. Oily, odorous skin, dysphonia, oligomenorrhea, and amenorrhea were equivocal or absent in most patients, but 6/11 women were postmenopausal at the time of the study. Four patients noticed lightheadedness, 11/15 patients had gained between 10-20 pounds in the past, and one patient had a carpel tunnel syndrome. Examination showed definite or equivocal acromegaloid facies in 14/15 patients and it was rated severe in three patients. Acral enlargement was present in all patients and rated severe in 6/15 patients. Heel pad measurements ranged from 19 to 31 cm in five patients, but only one patient had radiographic tufting. The sella turcica was borderline enlarged in two patients and definitely enlarged in two others, for which one patient had previously received a hypophysectomy. Visual fields were abnormal in 4/11 patients. Hypertension was present in 8/15 patients and borderline in two patients. The GTT was abnormal in 12/15 patients, but two were known to have 919

Table 1. Summary of the Clinical Manifestations in 15 Patients with Acromegaloidism Patient Number

Age/sex Years of acral or facial enlargement Increased headaches

Oligoamenorrhea Arthralgias Hyperhidrosis Hypertrichosis Hyperpigmentation Paresthesias Weight gain Oily odorous skin Fatigue or weakness Dysphonia Acromegalic facies Acral enlargement Frontal bosslation Prognathism Visceramegaly Enlarged sella Abnormal visual fields Hypertension Abnormal GTT Percent obesity Lactorrhea ASHD Large relatives

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Glucose Tolerance Test and GH Suppression in Acromegaloidism Figure 1 shows the results of the GTT in 15 patients with acromegaloidism. The GTT was abnormal in 12/15 patients when based on the two hour glucose concentration expected for their age. Only three of 12 patients had increased fasting glucose concentrations, and 2/3 were known to have diabetes mellitus. The mean fasting GH and glucose concentrations were 2.2 ng/ml and 93 mg/dl respectively in these subjects. The mean glucose concentration increased to 172 mg/dl during the GTT, which suppressed the mean GH concentration to 0.6 ng/ml. The GH concentration was sup920

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42M 42F 58M 17M 58F 57F 33F 62F 49F 21F 42F 57F 67F 17F 46F 8 4 0 3 >10 4 10 8 1 3 0 10 10 2 1/2 +* ± ± + + + + ++ 0 + 0 0 0 0 0 0 0 PMP PMP 0 PMP PMP 0 PMP 0 PMP 0 Ot 0 0 + + + + 0 + + 0 0 0 0 0 0 0 + ++ ++ + + 0 + + 0 0 0 0 0 0 0 0 0 0 + + 0 + 0 0 0 0 0 0 0 0 + 0 0 0 0 0 0 0 0 0 0 0 0 0 + ± ++ 0 + 0 0 0 0 0 0 0 0 0 0 + + + + + + + + + + 0 + 0 + 0 + + ± + + 0 0 0 0 0 0 0 0 0 0 + + ++ 0 + ± + + + 0 + 0 0 0 0 0 + 0 0 + 0 0 0 0 0 0 0 0 0 0 + ± + + + ± + ++ + ++ + + ++ 0 + + + +++ ++ ++ ++ + + ++ + + ++ + 0 + ± ++ + + 0 + 0 0 0 0 0 0 0 + + + ± ± 0 0 0 0 + 0 0 0 + + 0 0 ± ± 0 0 0 + 0 0 + 0 0 0 0 0 0 + 0 0 0 0 0 0 0 0 + 0 0 + 0 + + 0 + 0 0 0 + 0 0 0 0 + 0 0 0 ± ± + + + 0 0 + + + + + + 0 0 + + + 0 0 0 + + + + + + + + 18 32 25 9 33 13 22 50 8 12 27 17 34 30 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 + 0 0 0 + + 0 0 0 + + 0 0 0 ± + + + + + + 0 0 0 0 0 0 0 0

*(+)=present on scale of 1-3; t(0)=absent;

diabetes. Obesity of 10 percent or greater was present in 13/15 patients, and seven patients had known largestatured relatives. Frontal bosselation, prognathism, and visceromegaly was equivocal or absent in all except one patient, and none of the patients had lactorrhea.

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(

)=equivocal; (PMP)=postmenopausal.

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Pituitary function and growth hormone dynamics in acromegaloidism.

Pituitary Function and Growth Hormone Dynamics in Acromegaloidism Robert B. Mims, MD Los Angeles, California Acromegaloidism is a condition which res...
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