Mercury Intoxication and Arterial Hypertension: Report of Two Patients and Review of the Literature

Two children in the same household with symptomatic arterial hypertension simulating pheochromocytoma were found to be intoxicated with elemental mercury. The first child was a 4-year-old boy who presented with new-onset seizures, rash, and painful extremities, who was found to have a blood pressure of 171/123 mm Hg. An extensive investigation ensued. Elevated catecholamines were demonstrated in plasma and urine; studies did not confirm pheochromocytoma. Mercury levels were elevated. These findings prompted an evaluation of the family. A foster sister had similar findings of rash and hypertension. Both had been exposed to elemental mercury in the home. The family was temporarily relocated and chelation therapy was started. A Medline search for mercury intoxication with hypertension found 6 reports of patients ranging from 11 months to 17 years old. All patients showed symptoms of acrodynia. Because of the clinical presentation and the finding of elevated catecholamines, most of the patients were first studied for possible pheochromocytoma. Subsequently, elevated levels of mercury were found. Three children had contact with elemental mercury from a broken thermometer, 2 had played with metallic mercury and 1 had poorly protected occupational exposure. All responded to chelation therapy. Severe systemic arterial hypertension in infants and children is usually secondary to an underlying disease process. The most frequent causes of hypertension in this group include renal parenchymal disease, obstructive uropathy, and chronic pyelonephritis associated with reflux and renal artery stenosis. Less frequent causes include adrenal tumors, pheochromocytomas, neurofibromas, and a number of familial forms of hypertension. Other causes include therapeutic and recreational drugs, notably sympathomimetics and cocaine, and rarely, heavy metals. In children with severe hypertension and elevated catecholamines, the physician should consider mercury intoxication as well as pheochromocytoma. The health hazards of heavy metals need to be reinforced to the medical profession and the general public.