Acute copper sulphate poisoning: a forgotten cause of severe intravascular haemolysis

Abstract

Acute copper sulphate poisoning is a rare mode of attempted suicide. A 25-year-old male was admitted to our hospital with severe gastrointestinal symptoms after voluntary ingestion of an unknown amount of copper sulphate solution 18 h before admission. Laboratory tests showed leucocytosis with a left shift (leucocyte count 55 · 10/l), haematocrit 0AE44, haemoglobin concentration 149 g/l and platelet count 206 · 10/l. On day 3, severe intravascular haemolysis occurred with haematocrit 0AE25, haemoglobin 93 g/l and increased reticulocytes (9AE4%). The patient also developed rhabdomyolysis and mild renal and liver impairment. Blood film examination showed anisocytosis, poikilocytosis, marked echinocytosis, pyknocytosis including many blister and bite erythrocytes with precipitation of haemoglobin, microspherocytosis and basophilic stippling (left). His serum samples were initially dark brownish-red, due to haemoglobinaemia and methaemoglobinaemia, which resolved gradually after successful treatment (right). Serum and urine copper levels were elevated. The course was favourable after symptomatic treatment and copper chelation therapy with dimercaprol. Intravascular haemolysis is largely due to copper sulphate being a potent oxidant that overwhelms the capacity of the pentose shunt to protect against oxidation. Copper inhibits glucose-6-phosphate dehydrogenase and glutathione reductase and increases cell permeability because of inhibition of the Na/K ATPase pump.