ABSTRACT
We studied retrospectively 25 cases of primary aldosteronism which had presented at Siriraj Hospital between 1980 and 1993. There were 10 males and 15 females (M:F = 1:1.5), aged from 26-64 years old (average 43 years). The duration of the illness varied from 1 to 20 years (5.64 + 4.48 years). The presenting symptoms were proximal muscle weakness of extremities, 16 cases (64%) ; headache, 9 cases (36%) ; unable to stand up after sitting, 6 cases (24%) ; exertional dyspnea, 5 cases (20%) ; nocturia, 3 cases (12%) ; orthopnea, 1 case (4%) and arrhythmia with fainting, 1 case (4%). The patients with cardiac arrhythmia had a very low level of serum potassium (1.8 mEq/L). Physical examination revealed left ventricular hypertrophy in only 5 cases (20%). There was very little change in the ocular fundi but every case had high blood pressure ranging from 150-240/100-150 mm.Hg. (average 176.67 + 24.50/114.26 + 12.46 mm.Hg). Serum sodium varied from 134-152 mEq/L (average 145.58 + 4.42 mEq/L). Serum potassium was 1.3-3.3 mEq/L (average 2.11 + 0.48 mEq/L). Serum bicarbonate was high, 25-50 mEq/L (average 31.84 + 5.81 mEq/L). No significant change in BUN and creatinine was observed. Potassium in a twenty four hours urine specimen was 11.04-78 mEq/day (average 40.84 + 5.81 mEq/day). To confirm the diagnosis and localize and lesion a CT scan of the adrenal gland was performed and tumor masses were found on the right, 9 cases (36%) and on the left, 16 cases (64%). Surgical removal was carried out in only 20 cases. Golden yellowish tumours were excised varying in size from 1*0.3 – 3.5*2 cms. Pathological studies revealed 18 cases (90%) of adenoma and 2 cases (10%) of hyperplasia. Of those with adenoma, blood pressure in 13 cases (72.22%) returned to normal after surgery but the other 5 cases (27.78%) still had high blood pressures still needed antihypertensive treatment. Serum potassium returned to normal in both groups of patients, adenoma and hyperplasia.