Pulmonary Amyloidosis with Pulmonary Arteriovenous Fistula: Discussion
Amyloid deposition in the vascular wall is commonly seen in amyloidosis and is known to make vessels fragile. Amyloidosis has been reported to cause massive hemorrhage in the skin, urinary bladder, gastrointestinal tract, and central nervous system.* As for pulmonary amyloidosis, amyloid deposition in the vascular wall is well known in diffuse septal amyloidosis. Road et al reported a case of diffuse septal amyloidosis with massive hemoptysis caused by a ruptured pulmonary artery. Amyloid deposition in the vascular wall was regarded as having caused the rupture. In case of nodular amyloidosis, vascular deposition is also known, but few bleeding cases have been reported. read
The relation between vascular deposition of amyloid and AV fistula is not well known. Walley reported a case of gastric AV fistula with amyloid deposition, but no definitive explanation about the relation between amyloid deposition and AV fistula was given. On the other hand, about 50 percent of AV fistula are reported to be caused by hereditary hemorrhagic telangiectasis, but in our case, no specific cause was found except for the massive amyloid deposits in the walls of the fistula. In addition, the old chest roentgenogram clearly demonstrated that amyloidosis preceded the AV fistula. The coexistence of amyloidosis and AV fistula may be just a coincidence, but yet, these facts do strongly suggest that the amyloid deposition destroyed the vascular walls to form the AV fistula. To our knowledge, this is the first reported case in which pulmonary amyloidosis is suspected of causing an AV fistula in the lung.
In our case, the presence of multiple amyloidomas called our attention to the abnormal deposition of eosinophilic material in the fistula wall, but this may well have been disregarded if no other lesions had been present. We therefore suggest that amyloidosis be suspected as one of the etiologic factors when pulmonary AV fistula is present.