Type 1 renal tubular acidosis with sensorineural deafness.

We report a case of Type 1 Renal Tubular Acidosis (RTA) in association with sensorineural deafness. Inherited Type 1 RTA is usually autosomal dominant, though there is a rarer recessive form associated with nerve deafness. Simple alkali replacement can correct the systemic metabolic defect, but does not appear to ameliorate hearing loss.

Plasma cortisol response to 1-24 adrenocorticotropin in patients with treated/untreated sellar & suprasellar mass lesions.

BACKGROUND & OBJECTIVES: One microgram short synacthene test is widely recommended as a screening test for evaluation of hypothalamo-pituitary-adrenocortical axis in patients with secondary adrenal insufficiency. Information on adequacy of cortisol response to this dose at different periods of the day in patients with hypothalamic-pituitary disorders is not available. Hence, this study was designed to assess the adequacy of cortisol response to 1 microg 1-24 adrenocorticotropin (ACTH) at 0800 h and 1600 h in patients with sellar and suprasellar mass lesions. METHODS: Thirty five consecutive patients with sellar and suprasellar mass lesions with mean age of 43.0+/-14.4 yr and 36 healthy controls with mean age of 32.3+/-9.0 yr were studied after obtaining informed consent. Maintenance doses of glucocorticoids in these patients were discontinued appropriately. On day 1, prestimulated and stimulated plasma cortisol samples at 0800 h and at 30 and 60 min following i.v. bolus of 1 microg 1-24 ACTH were collected. While on day 3, plasma cortisol samples were similarly collected at 1600 h. Cortisol estimation was done by a sensitive and specific radioimmunoassay. Stimulated plasma cortisol of 500 nmol/l or higher was defined as a normal response. RESULTS: In healthy controls, the prestimulated and peak cortisol levels at 0800 h (377.5+/-93.3 and 729.1+/-183.2 nmol/l) were higher (P<0.001 and P<0.01) than those at 1600 h (230.1+/-75.7 and 665.8+/-138.6 nmol/l). All subjects had a cortisol response of 500 nmol/l or higher in response to 1 microg 1-24 ACTH both at 0800 and 1600 h. In the patients' group, the prestimulated plasma cortisol at 0800 h (250.3+/-169.7 nmol/l) was higher (P<0.001) than that at 1600 h (166.3+/-128.9 nmol/l), while the peak cortisol response was comparable (P>0.05) in the morning as well as in the evening (490.9+/-309.4 vs 464.8+/-318.4). In 27 patients (77%) the morning and evening stimulated cortisol response to 1 microg 1-24 ACTH was consistent (normal in 13 and subnormal in 14) but was discrepant in the remaining 8 (23%). In 7 of these 8 patients, cortisol response was normal at 0800 h but not at 1600 h, while in only one, normal response was seen at 1600 h but not at 0800 h. INTERPRETATION & CONCLUSION: The demonstration of normal peak cortisol response to 1 microg 1-24 ACTH at 0800 h but not at 1600 h in substantial number of patients with sellar and suprasellar mass lesions suggests preference to morning for performing this test.

Maxillary mass as the presenting manifestation of papillary thyroid carcinoma.

A case of follicular variant of papillary thyroid carcinoma presenting with a right maxillary mass is described. This is perhaps the first instance of maxillary metastasis from papillary thyroid carcinoma.

Plasma cortisol response to 1 microgram adrenocorticotropin at 0800 h & 1600 h in healthy subjects.

BACKGROUND & OBJECTIVES: Cortisol response to 250 micrograms adrenocorticotropin (ACTH) exhibits no circadian variation. Information on the circadian variation, if any, in cortisol response to 1 microgram ACTH, which is considered as a physiological dose is not available. As the 1 microgram ACTH stimulation test is projected as an outpatients procedure with no time constraint, this information is very important. Hence, this study was designed to assess whether any circadian variability exists in cortisol response to 1 microgram ACTH in healthy subjects. METHODS: Thirty six healthy volunteers (23 male and 13 female) with mean age of 32.2 +/- 9.0 yr were consecutively studied after obtaining informed consent. On day 1, prestimulated and stimulated plasma cortisol samples were collected at 0800 h and, at 30 and 60 min following an intravenous bolus of 1 microgram ACTH, and on day 3, plasma cortisol samples were similarly collected at 1600 h. Cortisol estimation was done by a sensitive and specific radioimmunoassay. Stimulated plasma cortisol of 500 nmol/1 or more was defined as a normal response. RESULTS: The prestimulated and peak cortisol levels at 0800 h (377.5 +/- 93.3 and 729.1 +/- 183.2 nmol/l) were higher (P < 0.001 and P < 0.01) than those at 1600 h (230.1 +/- 75.7 and 665.8 +/- 138.6 nmol/l). However, a stimulated cortisol response of 500 nmol/l or more was observed at both 0800 h and 1600 h in all subjects at 30 min but not at 60 min. The [symbol: see text] (peak-basal) response was higher at 1600 h than that at 0800 h (432.8 +/- 136.8 vs 351.5 +/- 177.3, P < 0.01). INTERPRETATION & CONCLUSION: The demonstration of normal cortisol response to 1 microgram ACTH both at 0800 h and 1600 h suggests that the test can be performed at any time of the day.