Benign paraproteinaemias.

Incidence of Paraproteinaemia in Blood Donors

“…It has already been pointed out that in terpretation of population surveys and com parison of different case materials need some caution owing to various factors which can influence to a great extent the frequency of M components [13,24] per sex and age and did not show any sig nificant decrease throughout the time of ob servation. Bence Jones proteinuria has never been demonstrated in any donor with para- demonstrate small amounts of paraproteins.…”

“…Although no bone marrow and skeletal axis x-ray exami nations were carried out, B cell malignancy appears to be highly improbable in our do nors with paraproteinaemia. This opinion seems justified by the steady level of the M components over a 5-year period, by the absence of immunosuppression and Bence Jones proteinuria, which are altogether in contrast with the malignant character of the monoclonal gammopathies [9,13,15,20,25,28,30], It should be pointed out, however, that definitive conclusions will probably re quire a very protracted follow-up [13,15,22,25,30], Unlike the finding of Kohn and Srivastava [14], who reported a preponderance of blood group A in donors with paraprotein aemia, in our cases with monoclonal gammopathy there was no significant deviation from the normal distribution of the ABO profiles. No correlation has been observed between presence of M component and number of blood donations.…”

“…In view of the possible transmissibility of myelomatosis [21], Kohn [12] suggested that blood from donors in whom paraproteins have been detected should not be used for transfusion. Although most paraproteinaemias detected by chance in other wise normal and healthy persons are prob ably to be regarded as benign, Kohn'% sug gestion appears fully justified if we consider that, at present, there are no absolutely reli able criteria for establishing with certainty at the time of the discovery that a parapro tein is benign and a malignant immunocyte disease will not develop [9,13,15,25,28,30]. Some apparently benign paraproteinaemias may be latent (or a prodromal stage of) myelomas remaining symptomless for a very long time, and malignant evolution has been reported to occur occasionally after many years of apparent benignity [7,15,16,22,28].…”

“…In fact, subopti mal electrophoretic techniques may fail to The increased frequency of monoclonal gammopathies resulting from the use of more sensitive electrophoretic techniques may reflect an increased recognition of 'benign' forms, which appear to be more frequently associated with low levels of para protein [2,9,13,15,20,25,28,30], Al though the extensive application of screen ing procedures which enable detection of an increasing number of monoclonal immuno globulins may arise more diagnostic prob lems, the physiopathological and clinical im plications of the discovery of a paraprotein, even at very low concentration, should not be disregarded. Detection of such an M component should warrant further investi gations and subsequent reexaminations, not only because it is of obvious importance to assess whether the underlying immunocyte abnormality is likely to be malignant or be nign.…”

“…The frequency with which M components are detected appears to vary considerably depending on the composition of the popu lations studied, especially with respect to age distribution and state of health [1,7,13,14,24,28,30]. In spite of the development during the last few years of more sophisticated tech niques of protein analysis, the simple elec trophoretic separation of serum proteins fol lowed by visual inspection of the pattern re mains an indispensable tool in screening for monoclonal immunoglobulin abnormalitities [8,13,18,23], However, improved electro phoretic techniques, capable of better reso It is well known that the discovery of a serum M component (or paraprotein) can not be regarded as synonymous with myelo ma or related malignant immunoproliferative diseases. Paraproteins have been en countered in association with a wide variety of conditions rather heterogeneous with re spect to aetiology and pathogenesis and also in apparently healthy persons [1,3,7,10,20,24,[28][29][30].…”