In this case report, the authors report the presence of two supposedly antagonic immune diseases in the same patient. The patient is a 45-year-old white woman with a history of asthma and allergic rhinitis for the last 10 years. Asthmatic symptoms were present and were triggered after exposure to dust and mold. Her Human T-Lymphotropic Virus Type I (HTLV-I) seropositive status was detected by chance five years ago during a routine screening for blood donation. Skin prick tests were positive for Dermatophagoides pteronyssinus, Dermatophagoides farinae and Blomia tropicalis. Cytokine levels in unstimulated cultures were: IFNgamma= 1195 pg/ ml, TNFalpha = 460 pg/ml, IL5 = 41 pg/ml and IL10 = 265 pg/ml.