Dapsone-induced methhaemoglobinaemia: a source of diagnostic confusion.
Arterial desaturation as measured using pulse oximetry may not reflect cardiorespiratory disease; other possible causes, including certain drugs, should be sought. Within the literature, examples exist of dapsone-induced methaemoglobinaemia causing diagnostic confusion, particularly where respiratory disease is a feature. Few cases have been reported that demonstrate the potential of relatively low levels of methaemoglobinaemia to upset pulse oximetry readings. We describe three examples of dapsone-induced methaemoglobinaemia emphasising the potential for low-grade methaemoglobinaemia to cause diagnostic confusion. Widespread use of the pulse oximeter indicates this problem may occur more regularly, hence there is a need for increased awareness.
Craig
D
D
Department of Haematology, Royal Group of Hospitals Trust, Belfast, UK.
Cadden
I S
IS
Gormley
W P
WP
Riley
M S
MS
Jones
F G
FG
McMullin
M F
MF
D000293:Adolescent; D000328:Adult; D003622:Dapsone / Q000009:adverse effects*; D003937:Diagnosis, Differential; D005260:Female; D005493:Folic Acid Antagonists / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008708:Methemoglobinemia / Q000139:chemically induced* / Q000175:diagnosis; D008875:Middle Aged; D010092:Oximetry; D016896:Treatment Outcome
D005493:Folic Acid Antagonists; D003622:Dapsone