Serum calcitonin in thyroid disorders and in pheochromocytoma kindred.

Serum calcitonin was determined by RIA in 59 healthy subjects (Group 1), 49 randomly selected patients with treated or untreated thyroid disorders (Group 2), and in 12 kindred of a pheochromocytoma index case (Group 3). Although most subjects in Group 2 had normal calcitonin levels, there were significant (p less than 0.001) differences between all three groups. Of the five patients in Group 2 with high serum calcitonin, one had medullary cancer of the thyroid, one had multiple endocrine neoplasia, one had acromegaly, and two remained undiagnosed. Increased serum calcitonin levels were also found in seven of 12 normotensive relatives of a patient with pheochromocytoma. It is therefore concluded that high serum calcitonin levels in patients with thyroid disorders strongly suggest the presence of C-cell neoplasia or medullary cancer of the thyroid.

Parathyroid adenomas evaluated by Tl-201/Tc-99m pertechnetate subtraction scintigraphy and high-resolution ultrasonography.

Thallium-201/technetium-99m pertechnetate subtraction scintigraphy of the parathyroid glands was performed in a prospective study of 33 patients who had undergone bilateral neck exploration for elevated serum calcium and serum parathyroid hormone levels. In 31 cases, the Tl-201/Tc-99m subtraction technique yielded an overall sensitivity of 81%, specificity of 99%, and accuracy of 94% for identifying solitary parathyroid adenomas. Tl-201/Tc-99m subtraction scintigraphy correctly identified 73% of parathyroid adenomas weighing less than 499 mg, 79% of those weighing 500-1,499 mg, and 100% of adenomas weighing more than 1,500 mg. In a subgroup of 24 patients with solitary parathyroid adenomas who underwent both scintigraphy and high-resolution sonography, the sensitivity, specificity, and accuracy of both procedures were similar.

Parathyroid adenomas studied by digital subtraction angiography.

Eighteen patients who had elevated serum calcium and parathormone levels were prospectively studied with intravenous digital subtraction angiography (DSA). Intravenous DSA of the neck and mediastinum was performed in the anteroposterior, the left anterior, and the right anterior oblique projections. The study was considered positive if an abnormal blush or blood supply was noted. Upon operation, 14 patients were confirmed to have parathyroid adenomas, of whom five had positive preoperative DSA examinations. Four patients were followed medically (three negative DSA, one positive DSA). A positive intravenous DSA may be useful to guide neck explorations for parathyroid adenomas; however, the low sensitivity of the study may limit its screening potential.

Plasma cortisol following injection of 1-39 or 1-18 ACTH.

Forty units of 1-39 ACTH of animal origin or 0.4 mg of synthetic 1-18 ACTH administered at 8 A.M. via either the intramuscular route to 10 subjects with intact adrenocortical function produced comparable increases in plasma cortisol at 1, 2, and 6 hours. The increase in plasma cortisol lasted at least 6 hours but less than 12 hours after intravenous crystalline 1-39 ACTH and at least 16 hours but less than 24 hours after the same dose of 1-39 ACTH administered as a depot gel via the intramuscular route. However, neither intravenous nor the intramuscular injection of 1-39 ACTH produced increases that were still evident at 24 hours. Following either the intramuscular or intravenous injection of 0.4 mg of the synthetic 1-18 ACTH, the plasma cortisol increase was still evident at the 24th hour. Our findings indicate that the plasma cortisol responses to either 40 units of exogenous 1-39 ACTH of animal origin or to 0.4 mg of a synthetic 1-18 ACTH are most consistent in the first 6 hours following either intravenous or intramuscular injection.

The so-called diabetes mellitus of ataxia telangiectasia.

Achados de 26 casos da literatura, somados aos 3 casos aqui descritos, sugerem que cerca de um terco dos pacientes com ataxia telangiectasia tem glicemia de jejum normal com hiperglicemias apos a ingestao oral de glicose. Estes achados enquadram-se nos criterios para tolerancia a glicose diminuida do assim chamado diabetes quimico. O diabetes do tipo II estava presente em apenas um dos 29 pacientes e nenhum deles tinha a deficiencia total de insulina que se encontra no diabetes tipo I. Entao, as hiperglicemias da ataxia telangiectasia representam apenas tolerancia diminuida a glicose e sao claramente distintas do diabetes, seja tipo I ou II. A frequente hiperinsulinemia basal ou apos sobrecarga de glicose de ataxia telangiectasia, com ou sem hiperglicemias, e compativel com a hipotese de bloqueio ou diminuicao de numero de receptores para insulina

Electroretinographic testing in diabetics: a comparison study of the Burian-Allen and the Henkes corneal electrodes.

A series of 57 diabetics underwent standard electroretinographic recordings for the purpose of testing the effect of insulin on the electroretinograms in diabetes mellitus, specifically on the oscillatory potential changes (Kozak et al., Jap. J. Ophthal. Suppl., 1979). Use of the speculum-type corneal electrode (Burian-Allen, Hansen Labs.,) produced 9 corneal abrasions in the first 28 patients in this series. However, when the technique of examination was altered by use of the Henkes-type bipolar electrode, only 2 abrasions were produced in the last 29 patients. These frequencies of abrasions are statistically different. The suggestion is made that electroretinographic tracings in diabetics the performed with the use of the Henkes bipolar low-vacuum corneal electrode (Medical Workshops, Holland).

Diabetic complications and their prevention or reversal.

Patients with Type I, i.e., insulin-deficient diabetes, Type II or non-insulin-deficient diabetes, and impaired glucose tolerance or so-called chemical diabetes are variably predisposed to develop macroangiopathy, i.e., atherosclerosis, microangiopathy or basement membrane thickening, and neuropathy. Once these morphologic changes appear, they in all probability will remain irreversible even when precise regulation is attained. Hence prevention is the only realistic goal.

Discrepancies between glycosuria and home estimates of blood glucose in insulin-treated diabetes mellitus.

Glycosuria can be a misleading indicator of blood or plasma glucose levels. Thus glycosuria may be present when blood glucose levels are within the normal fasting or postprandial range, and it may be absent when the blood glucose is distinctly above normal. In such patients the blood glucose must be measured, preferably by the patient, as a guide to insulin and other therapy. However, urine glucose tests are valid indicators in a minority of patients and are essential in all patients for the detection of acetone.

Parameters of good control in diabetes mellitus.

Optimal control of diabetes should achieve not only euglycemia and normal levels of glycosylated hemoglobin but also absence of the reversible concomitants of diabetes such as red cell rigidity, hyperlipidemia, increased capillary permeability, enlargement of the kidneys, proteinuria, etc. Unfortunately, in most patients consistent euglycemia cannot be assured even with two daily injections of insulin. However, self-measurement of blood glucose as a guide to insulin taken before each meal and at bedtime can, in selected patients, increase the frequency of normal glucose levels without undue hypoglycemia.