Primary aldosteronism diagnosis in the intensive care unit: resistant alkalosis and hypokalemia during severe sepsis with hyperlactatemia: a case report

Abstract

Background: Primary aldosteronism screening indications include hypertension (resistant, severe, early onset, with stroke/other comorbidities/sleep apnea), hypokalemia, adrenal incidentaloma, and primary aldosteronism first-degree relatives. We report rare diagnosis of primary aldosteronism in intensive care unit setting, characterized by resistant alkalosis and hypokalemia during severe sepsis with hyperlactatemia.

Case presentation: A 50-year-old Asian-Indian male patient with 18-year history of hypertension (blood pressure 166/104 mmHg) presented with acute septicemia and septic shock following an outpatient urethral dilatation. Despite aggressive management, including intravenous fluids, inotropes, antibiotics, and potassium supplementation, he exhibited severe alkalosis and resistant hypokalemia. Initial laboratory findings showed blood pressure 90/70 mmHg, heart rate 109 beats per minute, pH 7.49, serum lactate 123 mmol/L, sodium 141-144 mmol/L, potassium 2.7-2.9 mmol/L, and creatinine 1.2-1.54 mg/dL (106.1-136.1 µmol/L). Abdominal imaging revealed left adrenal adenoma (20 mm × 19 mm). Patient improved with supportive care and was discharged on day 10 with reinstituted antihypertensive medications. Post-hospitalization, endocrine evaluation confirmed primary aldosteronism with plasma renin activity 0.62 ng/mL/hour, serum aldosterone 43.2 ng/dL (1.20 nmol/L), and aldosterone-renin ratio 69.7. After initiation of spironolactone, blood pressure significantly improved (currently 122/76 mmHg).

Conclusion: Severe sepsis and septic shock in the intensive care unit typically present with metabolic acidosis. This case highlights an atypical presentation of paradoxical, resistant hypokalemia and alkalosis during severe sepsis, leading to a diagnosis of primary aldosteronism. Does the "inbuilt" tendency to metabolic alkalosis in primary aldosteronism confer survival advantage during intercurrent episodes of sepsis and metabolic acidosis? Given the high prevalence of renin-independent aldosterone production and benefits of mineralocorticoid receptor antagonists, universal primary aldosteronism screening for newly diagnosed hypertension appears meritorious and cost-effective.

Keywords: Hyperlactatemia; Hypertension; Hypokalemia; Metabolic alkalosis; Primary aldosteronism; Sepsis.

Fig. 1

Abdominal imaging: a computed tomography scan: left adrenal gland shows an isodense soft tissue nodule (red arrow), indicating left adrenal adenoma, measuring 20 mm × 19 mm (15 Hounsfield units). b and c Magnetic resonance imaging scan: right adrenal gland is normal in size and signal intensity. Left adrenal gland shows a well-defined round to oval T1-weighted/T2-weighted iso- to hypointense lesion epicentered in the medial limb of the gland (red arrows), measuring 22 mm × 14 mm × 21 mm, indicating left adrenal adenoma. The lesion shows few areas of signal drop on outphase images. The lesion is slightly hyperintense on DWI (Diffusion-Weighted Imaging)

Fig. 2

Journey of the 50-year-old man with delayed and missed (and subsequent serendipitous) diagnosis of primary aldosteronism: 2004–2022–2024; serial salient clinical (systolic and diastolic blood pressure) and biochemical (serum potassium) features. Hypertension diagnosis in 2004. Red arrow marks September 2022 (emergency intensive care unit admission with events of urinary retention, urethral dilatation, acute septicemia, septic shock, hypotension, hypokalemia, leukopenia, and thrombocytopenia)