Hypokalemia, metabolic alkalosis, and hypertension in a lung cancer patient.

CASE PRESENTATION A 69-year-old man was admitted to hospital for the evaluation of refractory hypokalemia and metabolic alkalosis. The patient had a 1-year history of a stage pT4N0M1 non-small cell squamous lung carcinoma (NSCLC) that was managed by Pemetrexed (Alimta 500 mg/m every 21 days) for the last 6 months. The patient had a 45-pack/y history of smoking without history of alcohol abuse, hypertension, or diabetes mellitus. He was married, had 2 children without health problems and used to work as a truck driver. He had no family history of cancer or metabolic problems. He was in his usual state of health until 1 month before admission. His medication list contained only paracetamol every 6 h. Two weeks before admission, he was examined in the emergency department when his family noticed increasing muscle weakness. On admission in nephrology, blood pressure was 170/90 mm Hg, and heart rate was 76 beats per min. There was no peripheral edema, and his mucous membranes were dry. Skin color had recently become generally darker as confirmed by the patient. Cardiovascular and chest examination were unremarkable. Abdominal examination showed no central obesity, nor striae. Neurological examination showed normal reflexes and no localized sensory deficits. Bilateral proximal muscle weakness was noted: 4/5 and 3/5 in upper and lower limbs respectively. Routine peripheral blood and biochemical examination revealed hyperleukocytosis, hypokalemia, metabolic alkalosis, and hyperglycemia. Clinical and laboratory values are listed in Table 1. The patient was managed with oral and intravenous potassium supplementation without improvement. The primary diagnosis was severe dehydration associated with contraction metabolic alkalosis, hypokalemia, hypertension, and type 2 diabetes mellitus (fasting blood sugar 11 mmol/l with glycosuria at 18.6 mmol/l). Supportive treatments included hydration, potassium supplementation, antihypertensive, and oral antidiabetic medications. His alkalosis and hypokalemia partially improved. Endocrine laboratory studies were performed; results are listed in Table 2. Doppler ultrasound study of the renal arteries and adrenal computed tomography (CT) scan were performed.