RESUMEN
BACKGROUND: When routine blood chemistry shows elevated chloride alone, another anion (bromide, iodine, fluoride) may be involved. CASE REPORTS: Hyperchloremia and decreased anion gap was observed in four patients. Chloremia ranged from 134 to 174 mmol/l at initial blood tests. Careful history taking led to the discovery of long-term use of calcium bromogalacto-glucomate. Specific assay with inductively coupled plasma mass spectrometry (ICPMS) confirmed the presence of bromide in the blood. Chloridemia returned to normal levels after discontinuing use of bromine. DISCUSSION: Bromism is not a common diagnosis. Risks include neurological and psychiatric disorders due to bromide diffusion through the blood-brain barrier. Clinical manifestations have been described including skin lesions, digestive intolerance, and fever. Bromide is contained in certain prescription drugs. Patients should be warned against the adverse effects of overuse.