muramidase and Paraproteinemias

Hereditary, autosomal dominant amyloidosis, caused by mutations in the genes encoding transthyretin, fibrinogen A alpha-chain, lysozyme, or apolipoprotein A-I, is thought to be extremely rare and is not routinely included in the differential diagnosis of systemic amyloidosis unless there is a family history.. We studied 350 patients with systemic amyloidosis, in whom a diagnosis of the light-chain (AL) type of the disorder had been suggested by clinical and laboratory findings and by the absence of a family history, to assess whether they had amyloidogenic mutations.. Amyloidogenic mutations were present in 34 of the 350 patients (9.7 percent), most often in the genes encoding fibrinogen A alpha-chain (18 patients) and transthyretin (13 patients). In all 34 of these patients, the diagnosis of hereditary amyloidosis was confirmed by additional investigations. A low-grade monoclonal gammopathy was detected in 8 of the 34 patients (24 percent).. A genetic cause should be sought in all patients with amyloidosis that is not the reactive systemic amyloid A type and in whom confirmation of the AL type cannot be obtained.

Topics: Adult; Aged; Amyloidosis; Amyloidosis, Familial; Apolipoprotein A-I; Diagnostic Errors; DNA Mutational Analysis; Female; Fibrinogen; Genotype; Heterozygote; Humans; Kidney; Middle Aged; Muramidase; Paraproteinemias; Point Mutation; Prealbumin; Radionuclide Imaging

Topics: Aged; Aged, 80 and over; Antibodies, Monoclonal; Bence Jones Protein; Electrophoresis; Humans; Immunoglobulin Light Chains; Leukemia, Monocytic, Acute; Male; Muramidase; Paraproteinemias; Proteinuria

In a retrospective multicenter study by the Groupe Français de Cytogénétique Hématologique, chromosome investigation was undertaken in 120 cases of chronic myelomonocytic leukemia, which was diagnosed in accordance with the French-American-British (FAB) criteria. Chromosome abnormalities of the clonal type were present at diagnosis in 30% of the patients. Median age of these patients was lower than for these without karyotypic abnormalities, and prognosis was less favorable. The most frequently encountered characteristic chromosome change was monosomy 7; chronic myelomonocytic leukemia (CMLL) with monosomy 7 occurs in younger age groups and has a very poor prognosis. Next in frequency were trisomy 8, iso(17q), and a 12p anomaly. The latter may have to be classified among the so-called primary characteristic chromosome changes in leukemia. All chromosome changes were of the type usually found in myeloid proliferation, and no anomaly specific for CMML was discovered. Isochromosome 17q was found only during blastic phase. Several of the CMML cases with chromosome anomalies were secondary leukemias, and among these was one case with a homogeneously staining region (HSR), which is rarely reported in leukemia. A paraproteinemia was found in 12% of the patients. No correlation of its occurrence with presence or type of karyotypic anomaly could be found.

Topics: Adult; Aged; Chromosome Aberrations; Chromosome Disorders; Female; Humans; Karyotyping; Leukemia, Myeloid; Male; Middle Aged; Muramidase; Paraproteinemias; Retrospective Studies