Haemolysis and methaemoglobinaemia following naphthalene ball ingestion.

Naphthalene poisoning is a rare but potentially life-threatening cause of haemolysis and methaemoglobinaemia due to severe oxidative stress. We report a case of a previously healthy man in his 30s who presented at the emergency department with scleral icterus, peripheral oxygen saturation of 85% on pulse oximetry, haemoglobinuria and chocolate-coloured blood following the accidental ingestion of a 'white air freshener ball'. Arterial blood gas analysis revealed elevated methaemoglobin (MetHb) levels. Laboratory results showed severe haemolysis. Bedside solubility and flotation tests on the white ball suggested that the ingested substance was a naphthalene mothball. Treatment with red blood cell transfusion, ascorbic acid and folic acid led to clinical improvement and normalisation of MetHb levels. Infrared spectroscopy confirmed the presence of naphthalene in the white ball. Glucose-6-phosphate dehydrogenase deficiency was confirmed during outpatient follow-up. The patient achieved full clinical recovery.