Tubular myelin figures in the lung with Wilson-mikity syndrome

An electron microscopic examination of the lung from a patient with Wilson-Mikity syndrome revealed abundant tubular myelin in the atelectatic areas. The tubular myelin was seen free and adjacent to secreted lamellar bodies in the alveolar spaces as well as within macrophages, but never in type II cells. The transverse dimension of the tubular units ranged from 24 to 30 nm, and the distance between two tubules was 5-6 nm. Occasionally the center of a tubule contained a single electron dense particle. The structure of the tubular myelin presented here differs to some degree from that in rat lungs. To our knowledge, the presence of tubular myelin figures has not been reported in cases of Wilson-Mikity syndrome. Their relation to the etiology of the disease is totally unknown; however, our findings that they were present only in the area of atelectasis but not in emphysematous areas may be significant. An accumulation of similar cases with ultrastructural study and combined biochemical and physiological studies is awaited to permit some interpretation.