Some diseases that cause body odor are trimethylaminuria and bromhidrosis, according to Medscape and MedicineNet. Trimethylaminuria is an error of metabolism associated with the smell of rotting fish. Bromhidrosis is body odor that results from apocrine gland secretion. In some cases, eccrine gland secretion leads to body odor as well.
Trimethylaminuria happens when a substance called TMA occurs in excess in the sweat, urine and breath, reports MedicineNet. This occurs because of a mutation in a gene for an enzyme that metabolises tyramine, a substance in cheese. After eating cheese, those with this condition may also experience hypertension and tachycardia. The symptoms of trimethylaminuria often occur from birth onwards. Treatment for the condition includes dietary restrictions and use of special soaps and lotions that remove the excess TMA from the skin.
Bromhidrosis becomes problematic when it starts interfering with a person's life, explains Medscape. Treatment for body odor that results from gland secretion includes topical antibacterial agents, drying agents and treatment with botulinum toxin, or botox. Topical antibacterial agents reduce bacteria that contribute to unpleasant odors. Drying agents reduce gland secretions and treat bromhidrosis that results from apocrine or eccrine secretion. Botox injections reduce secretions from eccrine glands and the resulting odor.