Cystic changes in lung parenchyma. The rearrangement of the heavy chain gene demonstrated by PCR and the kappa restriction shown by the immunoperoxidase staining support a clonal B-cell proliferation. Alternatively, the process may represent systemic LCDD not yet diagnosed. The cystic lesions, noted radiographically and histologically, as destruction of alveolar walls around nodules, are discussed below. In both diseases, the deposits increase the morbidity of the underlying cellular proliferation.
Diagnosis is by biopsy of the affected organ.
Structural data on the light chains are limited. Liver and heart followed kidney in frequency of deposits. Pulmonary involvement was rare. As in amyloidosis, therapy is directed against the clonal cell population. As pulmonary involvement is rare, details of several cases are described below.