[kappa-light chain amyloidosis of the liver, a rare cause of liver enzyme elevation].

HISTORY AND ADMISSION FINDINGS: A 69-year-old man was admitted to the department of gastroenterology having for months had persistently elevated liver enzymes after discontinuing systemic antimycotic therapy. He reported loosing five kilogram of body weight in the past six months. No macroscopic or microscopic abnormalities had been found on esophago-gastroduodenoscopy.

INVESTIGATIONS: Congo-red staining of the liver biopsy revealed massive sinusoidal amyloidosis of the liver. Immunoelectrophoresis of the urine and serum, as well as bone marrow biopsy, ruled out multiple myeloma or Waldenström's disease. Immunohistochemical staining identified the amyloid protein as a IgG kappa light chain (KLC). The free light chain (FLC) test confirmed KLC monoclonal gammopathy with an abnormal free kappa to lambda chain (KLLC) ratio.

TREATMENT AND COURSE: Systemic KLC amyloidosis in this patient older than 65 years was given chemotherapy with melaphalan and dexamethasone (M-Dex). After three courses of M-Dex the renal clearance deteriorated and the serum N-terminal probrain natriuretic peptide (T-proBNP) had increased.

COURSE: The patient was included in a phase II clinical trial which evaluates the use of bortezomib in patients with amyloidosis. Normalization of the free KLLC ratio and the NT-proBNP level will serve as important prognostic indicators.

CONCLUSION: KLC amyloidosis is a rare cause of elevated liver enzymes. The nonspecific symptoms often delay the diagnosis. FLC testing is a helpful tool in identifying monoclonal gammopathies, even when immunoelectrophoretic tests are normals.