The Significance of Lymphocyte Blastogenesis in the Detection of a Specific Antigen Demonstrated by a Case of Hypersensitivity Pneumonitis Caused by Rhizopus

• Published in: Nihon Kyōbu Shikkan Gakkai zasshi Vol. 25; no. 10; pp. 1126 - 1134
• Main Authors: Tada, Shinya, Miyagawa, Hidefumi, Nabe, Makoto, Shiraishi, Takamasa, Makimoto, Kho, Sato, Kyo, Takeda, Sho, Oheda, Yasuaki, Kitade, Kimihiro, Kimura, Ikuro
• Format: Journal Article
• Language: Japanese
• Published: Japan The Japanese Respiratory Society 01.10.1987
• Subjects: Alveolitis, Extrinsic Allergic - etiology; Alveolitis, Extrinsic Allergic - immunology; Antigens, Fungal - analysis; Female; Humans; Hypersensitivity pneumonitis; Lymphocyte Activation; Lymphocyte blastogenesis; Middle Aged; Rhizopus; Rhizopus - immunology; T-cell subset
• ISSN: 0301-1542; 1883-471X
• DOI: 10.11389/jjrs1963.25.1126

In a patient with a chief complaint of exertional dyspnea admitted to our hospital, the chest X-ray film showed diffuse reticulonodular shadows and pulmonary function test demonstrated restrictive ventilation disturbance, decreased diffusion capacity and hypoxemia. Histological examination of a lung specimen biopsied with bronchofiberscopy revealed granulomatous alveolitis. Cellular contents in bronchoalveolar lavage (BAL) fluid consisted mainly of T-lymphocytes. Analysis of T-cell subset with OKT monoclonal antibodies (T4 as helper/inducer, T8 as suppressor/cytotoxic) showed enormous increase of the T8-positive cell population (74.2%) and decrease of T4 positive cell population (20.0%) resulting in decreased T4/T8 ratio as 0.27 in comparison with T-cell subset of BAL fluid of normal subjects, 57.4%, 29.7%, and 1.94, respectively. All these data support the diagnosis of hypersensitivity pneumonitis. Collected materials from the patient's environment were examined for detection of the causative agent. Positive precipitin in Ouchterlony's double diffusion method were found against Candida albicans, Rhizopus and moldy dust from refrigerator and air conditioner. Rhizopus was detected by culture of moldy dust of the refrigerator. The extracts of fungi and moldy dust were applied to blastogenic response of lymphocytes from BAL fluid and peripheral blood. High responsiveness of lymphocytes in BAL fluid to Rhizopus and moldy dust from the refrigerator support the pathogenic role of Rhizopus which proliferated around the cooling fan of the refrigerator and contaminated the environment enough to provoke hypersensitivity pneumonitis. Replacement of the contaminated refrigerator prevented the recurrence of symptoms in the following years. This is the first case report of hypersensitivity pneumonitis with Rhizopus. In this study, the significance of lymphocyte blastogenesis as well as precipitating antibody in deflection of the causative agent from the patient's environment was clearly shown.