Acquired Hyperzincaemia Due to Zinc-Laden Denture Adhesives Leading to Hypocupraemia as a Cause of Neutropenia

INTRODUCTION: Copper deficiency or hypocupraemia is a rare cause of anaemia and neutropenia. CASE DESCRIPTION: We hereby present the case of a 34-year-old female with gastric bypass surgery who presented with neutropenic fever, abdominal pain and diarrhoea, later found to have extended-spectrum beta-lactamase resistant Escherichia coli urinary tract infection and small bowel bacterial overgrowth syndrome, with her anaemia and neutropenia being caused by copper deficiency due to hyperzincaemia induced by using zinc denture adhesive cream. DISCUSSION: Various causes of copper deficiency have been recognized including, but not limited to, malnutrition, gastrectomy, gastric bypass surgery, protein-losing enteropathies (coeliac disease, tropical sprue), Wilson disease and Menkes syndrome. Copper deficiency caused by zinc overuse is not very prevalent. The haematologic abnormalities associated with copper deficiency are neutropenia, sideroblastic anaemia and/or pancytopenia. CONCLUSION: Because of its low prevalence and nonspecific haematologic and clinical manifestations, the diagnosis of zinc-induced copper deficiency (ZICD) can be missed. LEARNING POINTS: Zinc toxicity is a rare cause of hypocupraemia. The bone marrow and haematological manifestations of copper deficiency are not pathognomonic but include sideroblastic anaemia, pancytopenia or neutropenia. Early detection of hypocupraemia as a cause for neutropenia will improve morbidity and mortality by avoiding untoward infections due to neutropenia, neurological decline or unnecessary interventions.