Normotensive hypokalemic primary hyperaldosteronism mimicking clinical features of anorexia nervosa in a young patient: A case report

RATIONALE

The typical clinical presentations of patients with primary aldosteronism (PA) include generalized weakness, fatigue, high blood pressure, and potassium deficiency. However, normotensive PA is rare. Therefore, an atypical presentation of normal blood pressure is a challenge for the diagnosis and treatment of PA.

PATIENT CONCERNS

A 43-year-old, thin, and tall woman (body mass index, 18.6 kg/m) with generalized weakness for 1 day presented to our emergency department, where hypokalemia was a significant finding. The initial diagnosis was anorexia nervosa with the evidence of renal potassium wasting with low urinary sodium and chloride levels, metabolic alkalosis, normal blood pressure, and low body mass index. However, neither vomiting features nor other specific induced vomiting features were noted.

DIAGNOSES

The laboratory examination revealed high plasma aldosterone level, low plasma renin activity, and extremely high aldosterone-to-renin ratio indicating the diagnosis of PA, confirmed via adrenal computed tomography.

INTERVENTIONS

Surgical adrenalectomy was performed. Pathological diagnosis was a benign cortical adenoma.

OUTCOMES

Patient's serum potassium level and hormonal status became normalized after surgical removal of adrenal adenoma. She fully recovered without any further sequelae.

LESSONS

It is too early to rule out PA based on the presence of normal blood pressure in a patient with metabolic alkalosis and renal wasting hypokalemia. Moreover, PA should be considered in a normotensive patient with an unknown hypokalemic etiology to avoid delayed diagnosis and treatment.

An atypical presentation of high potassium renal secretion rate in a patient with thyrotoxic periodic paralysis: a case report

Background

Hypokalemia is one of the most common clinical electrolyte imbalance problems, and thyrotoxic periodic paralysis (TPP) is a leading cause of presentation to the emergency department. Low renal potassium secretion rates, a normal acid–base balance in the blood, and hyperthyroidism are the hallmarks of suspected TPP.

Case presentation

Here we report the case of a 36-year-old man who presented to the emergency department with a sudden onset of acute muscle weakness at 5 h prior to admission. Biochemistry tests revealed hypokalemia with hyperthyroidism and renal potassium wasting. TPP was initially not favored due to the presence of renal potassium wasting. However, his serum potassium level rebounded rapidly within several hours after potassium supplementation, indicating that the intracellular shifting of potassium ions was the main etiology for his hypokalemia. The early stage of TPP development may have contributed to this paradox.

Conclusion

Therefore, it is premature to rule out TPP based on the presentation of high renal potassium secretion rates alone. This finding may result in an incorrect impression being made in the early stage of TTP and may consequently lead to an inappropriate potassium supplementation policy.

Protective effect of tetrandrine on normal human mononuclear cells against ionizing irradiation

Tetrandrine, an alkaloid isolated from the plant Stephania tetrandra, at low concentration (2 micrograms/ml) was shown to protect normal human mononuclear cells in vitro against damage due to a single high-dose of ionizing irradiation (10 Gy). The cell survival rate increased from 58.3 +/- 2.2% in the irradiated group to 78.0 +/- 2.6% in the tetrandrine-pretreated group, and similarly, the percentage of necrotic cells declined from 20.7 +/- 2.5% to 10.7 +/- 1.9%, respectively. This protective effect of tetrandrine for cell surviving fraction increased in a dose-dependent manner. Tetrandrine was also found to inhibit inflammatory responses induced by irradiation including the release of superoxide (NBT [nitroblue tetrazolium] reduction decreased from 21.3 +/- 2.3% to 10.2 +/- 2.5%) and phagocytic activity (decreased from 80.7 +/- 3.8% to 50.7 +/- 2.3%, the same range level as that of the control group). However, the alkaloid demonstrated no effect on the production of nitric oxide. In terms of cell morphology, only two types were observed-normal or necrotic cells, and there were no characteristics of programmed cell death. These results indicate that tetrandrine possesses radioprotective activity against 10 Gy of ionizing irradiation and could suppress irradiation-induced inflammatory processes.