ABSTRACT
We have performed a systematic review of all new serum and urinary paraproteins detected over a six year period in an immunodiagnostic laboratory serving a population of 400,000 people. Clinical diagnoses and associated laboratory features were ascertained from a computerized laboratory database or from clinical notes. Over the period of study, serum or urine paraproteins were detected in 613 new patients. These consisted of 568 patients with serum paraproteins and 45 patients with urinary monoclonal free light chain (in the absence of a serum paraprotein). These paraproteins occurred more commonly in males and the frequency increased with age. Approximately 30% of the serum paraproteins and 60% of urinary monoclonal free light chain were associated with B cell lymphoproliferative disorders (multiple myeloma, plasmacytoma, Waldenstrom's macroglobulinemia, non-Hodgkins lymphoma, chronic lymphocytic leukemia, etc) with the remainder being labeled as monoclonal gammopathies of uncertain significance (MGUS). At clinical presentation, patients with lymphoproliferative disorders tended to have higher levels of paraprotein, B2 microglobulin, the presence of free urinary light chain and demonstrated molecular size heterogeneity of the paraprotein but there was considerable overlap. A good correlation was noted between paraprotein concentration and viscosity in most patients. In conclusion paraproteins were most frequently encountered in the context of a gammopathy of uncertain significance. Features which suggested lymphoproliferative disorders included higher levels of serum paraprotein (> 15 g/l), elevated levels of B2-microglobulin and the presence of urinary free high chain. However, as much overlap was seen with patients with MGUS, regular monitoring of paraprotein level is considered mandatory in the management of these patients.
Subject(s)
Adult , Aged , Aged, 80 and over , Biomarkers/analysis , Blood Viscosity/physiology , Cryoglobulins/metabolism , Female , Follow-Up Studies , Humans , Immunoglobulin A/immunology , Immunoglobulin G/immunology , Immunoglobulin M/immunology , Lymphoma, Non-Hodgkin/blood , Male , Middle Aged , Multiple Myeloma/blood , Paraproteins/immunology , South Australia/epidemiology , Waldenstrom Macroglobulinemia/bloodABSTRACT
Se estudian dos casos de Síndrome de Sjögren (SS) que se asocian al componente monoclonal (IgG Kappa y Lambda) describiendo especialmente la presentación con vasculitis a repetición del primero y el agrandamiento de glándulas salivales en el segundo. Ambos no cubren criterios para enfermedad alguna del colágeno ni se confirma la existencia de proceso linfoproliferativo maligno hasta la fecha. Se delimitan dos subsets en SS con distinta orientación evolutiva y se discute el significado de la aparición en sangre periférica de una paraproteína como estado pre-linfomatoso a veces de duración indefinida, siendo considerada la glándula salivar el primer sitio de transformación maligna