[A case of smoldering ATL associated with hypersensitivity pneumonitis]

A 37-year-old woman was admitted to our hospital with the complaints of cough, lymph node swelling. Chest X-ray film showed diffuse small nodular shadows in the bilateral lower lung fields. Bronchoalveolar lavage fluid revealed an increased proportion of lymphocytes (71%) with low OKT4/T8 ratio (0.26). Lung tissue biopsied by bronchofiberscopy showed the existence of interstitial pneumonia. Precipitating antibodies in this patient's serum against various antigens including Trichosporon cutaneum were positive. After admission, all symptoms resolved gradually without specific therapy. But, as soon as the patient was discharged and returned to her home, all symptoms including fever, cough, dyspnea and lymphadenopathy recurred rapidly. The diagnosis of hypersensitivity pneumonitis was made on the basis of these laboratory findings and clinical course. The patient died from respiratory failure after detection of anti-HTLV-I antibody, and autopsy revealed massive ATL cell infiltration of lung tissue, and immunoenzymatic analysis showed a high OKT4/T8 ratio (3.5). Chronic HTLV-1 infection since infancy was suspected in this case, to have modified the immune regulation of the lung, and to have led to the onset of hypersensitivity pneumonitis and the active immune response in the lungs, finally followed by the acute exacerbation of ATL.