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An autosomal recessive malodor condition characterized by extraoral blood-borne halitosis resulting from the accumulation of sulfur-containing metabolites. In extraoral blood-borne halitosis, malodorant compounds are carried to the lungs, where they enter the breath. Affected individuals have a cabbage-like breath odor, high levels of methanethiol and dimethylsulfide in oral and nasal breath, and elevated urinary excretion of dimethylsulfoxide in the absence of intake of dimethylsulfide-containing food or use of sulfur-containing medication, lower-gastrointestinal problems, and known metabolic defects, such as methionine adenosyltransferase deficiency and tyrosinemia.




Extraoral halitosis due to MTO deficiency
Extraoral halitosis with dimethylsulfoxiduria
Methanethiol oxidase deficiency
MTO deficiency


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