Clinical Observation on Hyperkalemic Distal Renal Tubular Acidosis / 대한신장학회잡지

PURPOSE: Renal tubular aicdosis (RTA) is a disorder of renal acidification out of porportion to the reduction in glomerular filtration rate. Type IV RTA refers to hyperkalemic metabolic acidosis resulting from aldosterone deficiency or resistance. The incidence of each type RTA has not been reported exactly, however reports on type IV RTA have been recently increasing. METHODS: A retrospective clinical analysis was performed in 50 patients with hyperkalemic distal renal tubular acidosis diagnosed between Jan. 1984 and Feb. 2003 at Department of Internal Medicine, Keimyung University, Dongsan Medical Center. RESULTS: From 1984 to 2003, 50 cases of hyperkalemic distal renal tubular acidosis were diagnosed. The mean age was 50.8+/-19.5 years. The two most common conditions were posttransplantation (28%), and diabetes mellitus (22%), which were followed by hypertension (12%), systemic lupus erythematosus (12%), chronic renal failure (12%), and others (26%). Asymptomatic hyperkalemia (34%), and muscle weakness (28%) were the two most common clinical presentations. All patients demonstrated normal anion gap acidosis with positive urine anion gap. The mean creatinine clearance was 25.6+/-16.4 mL/min. The mean baseline PRA and aldosterone levels were 3.82+/-7.16 ng/mL/hr and 110.02+/-108.2 ng/mL, respectively. Hyperkalemia was well responded to 9-alpha-fludrocortisone, furosemide, K-exchane resin, and combinations of these regimens. CONCIUSION: Type IV RTA is the most common type of RTA in children and adults, and can be an important cause of asymptomatic hyperkalemia. Therefore, type IV RTA should be included in the diffrential diagnosis of unexplained hyperkalemia in various clinical settings.

Chronic hyponatremia of Sheehan's syndrome / 대한내과학회지

Sheehan's syndrome has been attributed to ischemic damage of the pituitary gland or hypothalamic-pituitary stalk during the peripartum period. Well-described clinical features of Sheehan`s syndrome include hypothyroidism, growth hormone deficiency, hypogonadism, hypoprolactinemia, adrenal insufficiency, and different sodium and water disturbance. The occurrence of sodium and water disturbances associated with Sheehan`s syndrome depends on the degree of pituitary damage, time of onset since the initial pituitary insult, and concurrent medical conditions that also may play a role in sodium and water balance. Chronic hyponatremia is the most common presentation of altered sodium levels in patients with Sheehan`s syndrome. The chronic nature of the presenting hyponatremia suggests more subtle changes of panhypopituitarism or better adaptive mechanism. Although controversial, another mechanism proposed for hyponatremia in the chronic setting involves alternation in the renin-angiotensin/aldosterone system with resulting sodium wasting. We presented a patient with Sheehan`s syndrome associated with hyporeninemic hypoaldosteronism and hyponatremia 53 years old women, who had 4th baby delivery with severe blood loss about 25 years ago, was admitted to hospital because of general weakness. The patient was diagnosis Sheehan`s syndrome with hyponatremia. In addition, we performed hormonal study to find cause of hyponatremia. The results were hypopituitarism and hyporeninemic hypoaldosteronism. Hyponatremia was corrected by hormonal therapy (glucocorticoid,synthyroid,estrogen). The patient felt well-being sensation and was followed up the out-patient department.

A Case of Liddle's Syndrome Associated with Muscle Weakness / 대한신장학회잡지

Liddle's syndrome was described in 1963 by Liddle, et al., as the disease featuring a hypertension and hypokalemia but with negligible secretion of aldosterone. This syndrome, which morphologically belongs to an abnormal intrinsic tubular disorder with normal renal function, is characterized by hypokalemia, metabolic alkalosis, and hypertension due to the abnormal increase in excretion of potassium in distal tubules or collecting duct and the increase in reabsorption of sodium in distal tubules. This syndrome, which is rare disease, is observed with the low level of plasma and urinary aldosterone and suppressed plasma renin level and is known as dominant mode of inheritance with a family background. The authors paid attention to a 79-year-old man who showed a high blood pressure of 210/130mmHg as well as musle weakness, especially lower extremities due to metabolic alkalosis featuring a hypokalemia level of 2.0mEq/L when he was admitted to our hospital, Because his serum potassium were not improved with the medication of intravenous potassium supply, and his blood pressure continued to be high without the improvement of muscle weakness, we prescribed 300mg of spironolactone for two weeks. His symptom, however, was not cured. Then, instead of spironolactone, we prescribed 150mg of triamterene and a low salt diet which finally improved his symptoms. Because there has been no reported case in the Korean medical literature, we report a case of successfully treated Liddle's syndrome due to triamterene administration.

Hyperkalemia due to hyporeninemic hypoaldosteronism with liver cirrhosis and hypertension

A 49-year-old man with liver cirrhosis and hypertension was found to have hyperkalemia out of a degree of renal insufficiency and metabolic acidosis with low to normal anion gap, aggravated by volume contraction with diarrhea and medications (captopril, spironolactone and atenolol) interfering with potassium homeostasis. Plasma renin activity and serum aldosterone levels of this patient on a regular diet after discontinuation of medications were very low compared to those of five other cirrhotic patients with normokalemia as controls. Also, the renin-aldosterone stimulation testing on this patient performed by sodium restricted diet and furosemide, upright position and by angiotensin converting enzyme inhibition (captopril, 50 mg) showed the blunted renin and aldosterone responses to each of these stimuli, almost no changes from baseline renin and aldosterone levels, it was concluded that the underlying defect responsible for hyperkalemia in this case was hyporeninemic hypoaldosteronism and this was aggravated by other factors or drugs affecting potassium homeostasis.