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A case of dapsone induced methaemoglobinaemia
1Department of Respiratory Medicine, Beaumont Hospital, Dublin, Ireland. daviodwyer@gmail.com
Background:
We present a case of dapsone induced methaemoglobinaemia that occurred in a patient who presented to the Emergency Department of a University Hospital. It is an uncommon condition that requires specific and urgent treatment in severe cases.
Aims:
To describe and evaluate the presenting symptoms, signs, diagnosis and management of acquired methaemoglobinaemia.
Methods:
We describe a case of acquired methaemoglobinaemia as a result of dapsone ingestion with a literature review.
Conclusions:
Acquired methaemoglobinaemia is an uncommon condition that presents with non-specific signs and symptoms. It is caused by a variety of exogenous agents and results in a "saturation gap" between oxygen saturation on pulse oximetery and arterial blood gas analysis. Specific treatment with intravenous methylene blue is the treatment of choice. Full resolution can be expected with treatment but severe cases can be associated with shock and mortality.
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