ABSTRACT
We report on a patient who, at 36-years of age, was found to suffer from systemic ALys amyloidosis primarily affecting the gastrointestinal tract and kidney. Biopsy specimens from the gastrointestinal tract and kidney were used for histological, immunohistochemical and biochemical studies. Genomic DNA was extracted from peripheral blood leukocytes and analyzed by polymerase chain reaction and sequencing. Extended amyloid deposits were found in the upper gastrointestinal tract and entire colon, leading to erosions and gastrointestinal bleeding. Amyloid was found in the kidney resulting in mild proteinuria. Immunohistochemical and biochemical studies identified lysozyme as the amyloid protein. DNA analyses of the lysozyme gene revealed a T to C transversion at the first position of codon 112, indicating a replacement of Trp by Arg at residue 112. This mutation was not found in the lysozyme genes of the patient’s mother and daughter. To the best of our knowledge, this is the seventh report and the first German patient with the exceedingly rare ALys amyloidosis. ALys amyloidosis initially and commonly presents with gastrointestinal and renal symptoms.
