Proteinuria Bence Jones

Osteolytic bone lesions of multiple myeloma-The recommended dose is 90 mg given as a 4-hour infusion on a monthly basis. Patients with marked Bence-Jones proteinuria and dehydration should receive adequate hydration prior to pamidronate infusion. 

Monoclonal protein can be detected in serum, urine, or both in greater than 95% of patients with multiple myeloma (D16). Bone marrow plasma cells exceed 10%. Patients with advanced disease may excrete Bence-Jones proteins in urine. Both hypercalcemia and Bence-Jones proteinuria can contribute to renal failure (A6). 

Fig. 14. Malignant paraproteinemia. Electrophoresis on cellulose acetate of serum (above) and concentrated urine (below) reveals (i) Bence Jones proteinuria. In this case monoclonal bands are seen of each type. For L the relevant concentration to albumin indicates which are IgGL, L dimer, and L monomer (ii) loss of normal y-globulin (iii) a high serum level of paraprotein. Immunoelectrophoresis of urine reveals paraprotein bows of k, and X, yaXj and X2.

Fig. 15. Benign paraproteinemia. Electrophoresis on cellulose acetate of serum and concentrated urine reveals (i) no Bence Jones proteinuria (ii) no loss of normal y-globulin (iii) a low level of serum paraprotein. In this case the paraprotein is of post-y-mobility, is type GL, and is typically (but not exclusively) found in lichen myxedematosus. Reproduced by courtesy of the Proceedings of the Royal Society of Medicine (H30).

Where heart failure due to amyloidosis has already set in, we have had no success. In one patient macroglossia became less edematous, and caliper measurements confirmed that a previous width increase (of 1 cm each 4 months for 8 months) was arrested for 2 more comfortable years by the use of melphalan, before the reappearance of Bence Jones proteinuria and further width increase heralded relapse and death. 

IgG (53% myelomatosis) patients present on average with a serum level of 4.3 g/100 ml (because of the longer T, see Section 2.1). They have the most severe immune paresis, so that infection requiring hospitalization is common (60% within three years) but less hypercalcemia (33%), renal failure (16%), Bence Jones proteinuria (60%), and amyloidosis. Apparent hyponatremia (8%, see Section 7.5.3), viscosity syndrome (4%, see Section 7.5.6), and cryoglobulinemia (4%, see Section 7.5.5) with myelomatosis relate to IgG paraproteins. 

A monoclonal band can be found in most cases, but serum must be separated at 37°C. The ESR in the cold is much higher than at 37°C, due to massive agglutination in the cold. The monoclonal IgM is readily measured (C14), averaging 0.4 g/100 ml (range 0.1-2.4). The residual IgM and IgA and IgG are usually normal. In some 30% patients, mostly those with high IgM levels, a subnormal level of IgA is found. The cold agglutinin IgM is mostly well produced, with no Bence Jones proteinuria or 7 S IgM, and, on a molecular basis, specific lytic activity against enzyme-treated red cells was very similar. 

Where Bence Jones proteinuria, 7 S IgM, subnormal IgG, or atypical cold agglutinin (anti-i, type L, etc.) are found, the probability of lymphosarcoma looms large (C2, C14). Some 10% of IgM lymphomata present with atypical cold agglutinins, and conversely disease terminates as lymphosarcoma. Apart from these, the prognosis is fair, for this would be a benign paraprotein in most cases, were it not for its hemolytic potential. 

With IgM as the paraprotein, 25 known examples of radiological and clinical myelomatosis have been collected (H28). There is thus no doubt this is an entity accounting for 0.5% of all myelomatosis and some 2% of all IgM paraproteinaemia. Typically this disease differs from 7.7.1 in that the IgM level has been on the low side (average 1.9 g/100 ml), with heavy Bence Jones proteinuria and marked immune paresis. It has been the myelomatosis that has brought the patient to the doctor. At post-... 

These are uncommon and cannot be diagnosed with complete assurance until some 10 years of observation have passed. In general in Britain such patients are symptomless and have normal lymph nodes, spleen, and bone marrow. (In Africans the condition may be associated with parasitic infections, see M17.) The serum level is mostly under l.Og/100 ml, and hitherto always under 2.5g/100 ml. It shows no tendency to rise with many years of follow-up indeed it may disappear spontaneously. In our experience there is no Bence Jones proteinuria, and IgA and IgG levels are usually normal. Such apparently benign IgM paraproteins can be found in relatives of patients with malignant IgM paraproteins (S9), emphasizing the need for careful follow-up. 

Wong WK, Wieringa GE, Stec Z, Russell J, Cooke S, Keevil BG, Lockhart S. A comparison of three procedures for the detection of Bence-Jones proteinuria. Ann Clin Biochem 1997 34 371-374. 

Marshall T, Williams KM. Electophoretic analysis of Bence Jones proteinuria. Electrophoresis1999 20 1307-1324. 

This man is suffering from multiple myeloma. He is one of the approximately 20% of patients with myeloma that do not have a paraprotein in the serum but have Bence-Jones proteinuria. His renal function should be tested and hypercalcaemia should be excluded. 

Paraprotein band on etectropturesis. Confinn and characterise with immune electrophoresis otasma cells T in bone marrow. Bence-Jones proteinuria... 

Several syndromes of renal tubular dysfunction, including hypouricemia, have previously described in patients with malignant diseases. A Fanconi-like syndrome has been observed in several cases of multiple myeloma in association with Bence-Jones proteinuria. 

A test for the detection of Bence Jones proteinuria which consists of adding acetic acid and sodium chloride solution to the urine. Precipitation occurs if Bence-Jones protein is present. 

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