Diffuse alveolar septal amyloidosis in generalised amyloidosis.

A case of generalized amyloidosis is reported which diffusely involved the alveolar septa. A 67-year-old Japanese housewife showed no clinical evidence of systemic disease. She had complained of anorexia and diarrhea for a year and finally died of pneumonia-like symptom. Autopsy revealed a generalized amyloidosis, in which amyloid materials deposited beneath the basement membrane prominently in alveolar septa, and slightly in glands of alimental tract, thyroid and kidneys, perireticularly in the myocardium and adipose tissues, focally in the interstitial spaces of urogenital tract, thyroid, eosphagus and pancreas, and within the walls of small blood vessels in many organs No amyloid tumor was detected in the respiratory system. Severe alveolar septal amyloidosis occurred diffusely in both lungs in this case. The arrangement of amyloid deposition in the lungs was discussed in relation to gas diffusion in the alveolar walls.