Sodium abnormalities are frequently present in central nervous system infections and may be due to cerebral salt wasting, syndrome of inappropriate antidiuretic hormone secretion, or adverse medication events. 

The prevalence of baseline hyponatremia and if it adversely impacts survival in cryptococcal meningitis (CM) remains unknown.

The present study conducted a secondary analysis of data from 2 randomized trials of human immunodeficiency virus-infected adult Ugandans with CM. It grouped serum sodium into three categories: <125, 125–129, and 130–145 mmol/L, and assessed if baseline sodium abnormalities were associated with clinical characteristics and survival.

The study observed-

• Of 816 participants with CM, 741 (91%) had a baseline sodium measurement available.
• 16% of the patients had grade 3–4 hyponatremia (<125 mmol/L), 26% had grade 2 hyponatremia (125–129 mmol/L), and 57% had baseline sodium of 130–145 mmol/L.
• Association of Hyponatremia (<125 mmol/L) with higher initial cerebrospinal fluid (CSF) quantitative culture burden, higher initial CSF opening pressure, lower baseline Glasgow Coma Scale score, and a higher percentage of baseline seizures.
• Association of Serum sodium <125 mmol/L with increased 2-week mortality in unadjusted and adjusted survival analyses compared to those with sodium 130–145 mmol/L.

This study shows that Hyponatremia is commonly present in CM and is associated with excess mortality. A standardized management approach to correctly diagnose and correct hyponatremia in CM is warranted.

Open Forum Infectious Diseases, Volume 9, Issue 7, July 2022, ofac301,