Acquired Factor X Deficiency Associated with Atypical AL-amyloidosis

• Published in: Internal Medicine Vol. 53; no. 16; pp. 1841 - 1845
• Main Authors: Furuhata, Masanori, Doki, Noriko, Hishima, Tsunekazu, Okamoto, Tomomi, Koyama, Takatoshi, Kaito, Satoshi, Oshikawa, Gaku, Kobayashi, Takeshi, Kakihana, Kazuhiko, Sakamaki, Hisashi, Ohashi, Kazuteru
• Format: Journal Article
• Language: English
• Published: Japan The Japanese Society of Internal Medicine 01.01.2014
• Subjects: acquired factor X deficiency; Aged; AL-amyloidosis; Amyloidosis - complications; Amyloidosis - metabolism; atypical amyloidosis; Factor X - metabolism; Factor X Deficiency - diagnosis; Factor X Deficiency - etiology; Female; Humans; Immunoglobulin Light Chains - metabolism; nephrotic syndrome; Serum Amyloid A Protein - metabolism
• ISSN: 0918-2918; 1349-7235
• DOI: 10.2169/internalmedicine.53.2191

We herein describe the case of a 77-year-old woman with acquired factor X deficiency that was likely caused by atypical amyloidosis. The patient developed severe gastrointestinal bleeding as a result of a significant decrease of factor X activity. Neither proteinuria nor diarrhea was observed as an initial manifestation. Although a bone marrow examination revealed direct fast scarlet-positive extracellular deposits, they did not exhibit red-to-green dichroism under polarized light. Immunofluorescence microscopy showed that the fibrillar proteins were positive for CD138 but negative for β2-microglobulin or amyloid A antibodies. These atypical pathological features of immunoglobulin light chain-amyloidosis in this patient might be related to its unique clinical presentation.