Detection of oligoclonal IgG kappa and IgG lambda bands in cerebrospinal fluid and serum with Hevylite™ antibodies. comparison with the free light chain oligoclonal pattern

<p>Abstract</p> <p>Background</p> <p>Oligoclonal IgG bands in cerebrospinal fluid that are absent in serum indicate intrathecal IgG synthesis and are a sensitive marker of CNS inflammatory diseases, in particular multiple sclerosis. It may be of interest to determine whether these bands are predominantly IgGκ or IgGλ.</p> <p>Methods</p> <p>We have used Hevylite™ antibodies and developed a technique for detection of oligoclonal IgGκ and IgGλ bands by means of isoelectric focusing followed by immunoblotting. The same technique was used for oligoclonal free κ and free λ detection. Among several techniques tested, affinity immunoblotting appears to be the most sensitive; it can detect less than 1 ng of IgGκ or IgGλ paraprotein. We compared oligoclonal IgG profiles with those of oligoclonal IgGκ and IgGλ. There was good agreement concerning the presence or absence of intrathecal synthesis. We observed the ratios between oligoclonal IgGκ and IgGλ bands, and they did not always match the ratios between free κ and free λ bands. We were also able to detect antigen-specific CSF-restricted oligoclonal IgGκ and IgGλ bands in neuroborreliosis. It remains to be determined subsequently by a clinically-oriented prospective study, whether predominant IgGκ/IgGλ or free κ/free λ can be observed more frequently in particular diseases with oligoclonal IgG synthesis.</p> <p>Discussion</p> <p>Very sensitive detection of oligoclonal IgGκ and IgGλ bands in cerebrospinal fluid with Hevylite antibodies is feasible; detection of antigen-specific IgGκ or IgGλ is possible as well. In particular situations, e.g. when difficulties arise in distinguishing between oligoclonal and monoclonal pattern, the test may be of considerable clinical value.</p

Bound and Free Light Chains in Subacute Sclerosing Panencephalitis and Multiple Sclerosis Serum and Cerebrospinal Fluid

Peer Reviewe

Concomitant HIV infection in newly diagnosed multiple myeloma patients is hard to recognise and should be tested for routinely in areas of high endemicity

Background. Over the past three decades much has changed in the treatment and outcomes of patients suffering concurrently from both multiple myeloma (MM) and HIV. While the prevalence of MM appears to be higher in HIV-positive individuals than in those who are uninfected, early recognition of patients suffering from both diseases is difficult and little information is available on their demographics and clinical presentation.Objective. To compare the presenting features of HIV-positive patients diagnosed with MM with those of HIV-negative patients.Methods. A single-centre, retrospective cohort study included 16 HIV-positive and 73 HIV-negative patients diagnosed with MM, in order to compare variables related to the clinical presentation of both conditions.Results. HIV-positive patients presented with MM at a significantly younger age, and had fewer osteolytic lesions, less renal impairment and lower neutrophil counts. Disease stage, gender, pathological fractures, bone marrow plasmacytosis, plasmacytomas and lymphocyte counts were comparable, emphasising the difficulty of identifying these patients. The HIV-positive patients had relatively high CD4 counts and a low prevalence of abnormal Freelite kappa/lambda ratios. All HIV-positive patients presented with paraproteins of the immunoglobulin G (IgG) type, implying a possible relationship between MM and an IgG response to HIV antigens.Conclusions. On the basis of our findings and literature on the treatment of both diseases, we suggest that HIV be tested for routinely in younger MM patients, especially in areas with a high prevalence of HIV. The integration of our results into the sparse knowledge on the role of HIV infection-related MM provides possible new insights into the interaction between these diseases

Assessment of free light chains in the cerebrospinal fluid of patients with lymphomatous meningitis - a pilot study

BACKGROUND: Lymphomatous meningitis (LM) represents a severe complication of malignant lymphomas. While clinical suspicion is raised by symptoms ranging from mild disturbances of sensation to severe pain or impaired consciousness, the definite diagnosis of LM is often difficult to obtain. Since B-cell lymphomas are clonally restricted to express either kappa or lambda immunoglobulin light chain, we hypothesised that analysis of free light chain (FLC) ratios might facilitate the diagnosis of LM. METHODS: Kappa and lambda FLC were measured using a novel nephelometric assay in cerebrospinal fluid (CSF) and serum from 17 patients. 5/17 suffered from LM as demonstrated by cytology, immunocytology, and/or imaging procedures. RESULTS: Measurement of FLC concentrations in CSF was achieved for all 17 patients. FLC levels in CSF were lower than serum FLC levels in samples for the same patient obtained at the same time (p < 0.01). CSF and serum FLC concentrations correlated weakly in all patients irrespective of LM status. Significantly more patients with cytopathologically and immunohistochemically proven LM displayed abnormal kappa/lambda FLC ratios in CSF compared to individuals with no LM (p < 0.01). CONCLUSION: This is the first report demonstrating that a significant proportion of LM patients display an abnormal kappa/lambda FLC ratio in the CSF

Comparison of Free Light Chain Assays Freelite and N Latex in Diagnosis, Monitoring, and Predicting Survival in Light Chain Amyloidosis

OBJECTIVE: Measurement of serum free light chains (FLCs) is critical in diagnosis, prognosis, and monitoring treatment responses in light chain (AL) amyloidosis. We compare the Freelite assay (polyclonal antibodies to hidden light chain epitopes), which is the current gold standard, with a new assay: a mixture of monoclonal antibodies to light chain epitopes (N Latex). METHODS: We collected 240 serum samples from 94 consecutive patients with newly diagnosed AL amyloidosis (at least three serial serum samples during the first 6 months) analyzed at the National Amyloidosis Centre, London, from January 2011 to April 2012. Concordance in detecting abnormal light chain components and hematologic response was assessed at 2, 4, and 6 months. RESULTS: The κ and λ clonal light chain involvement was 21% and 79%, respectively, with an abnormal κ/λ ratio or detectable protein in 78.7%. Median κ, λ, and difference in involved and uninvolved FLCs by Freelite and N Latex assays were 17.3 vs 16 mg/L (R2  = 0.91), 48.8 vs 52.6 mg/L (R2 = 0.52), and 43.2 vs 39.1 mg/L, respectively. Discordant κ/λ ratios at presentation were as follows: 10 of 90 abnormal by Freelite/normal by N Latex and 11 of 90 abnormal by N Latex/normal by Freelite. CONCLUSIONS: Both FLC assays show good correlation in detecting the abnormal light chain subtype with discordance in absolute values and thus are not interchangeable

Laboratory practice is central to earlier myeloma diagnosis:Utilizing a primary care diagnostic tool and laboratory guidelines integrated into haematology services

Treatment advances have greatly improved survival, but myeloma is among the worst of all cancers for delayed diagnosis, causing serious morbidities and early deaths. This delay is largely because the symptom profile of myeloma has very low specificity, and in primary care, myeloma is rare. However, initiating the journey to diagnosis simply requires considering myeloma and sending blood to test for monoclonal immunoglobulin. Laboratory tests reliably detect monoclonal immunoglobulin, which is present in 99% of myeloma cases, so why do health care systems have such a problem with delayed diagnosis? The Myeloma UK early diagnosis programme has brought together diverse expertise to investigate this problem, and this article was prepared by the programme's working group for laboratory best practice. It reviews evidence for test requesting, analysis and reporting, for which there is large variation in practice across the United Kingdom. It presents a ‘GP Myeloma diagnostic tool’ and how it can be integrated into laboratory practice alongside a laboratory best practice tool. It proposes improved requesting and integration with haematology services for reporting and interpretation. Here the laboratory has a central role in creating efficient and cost-effective pathways for appropriate and timely bone marrow examination for myeloma diagnosis.<br/

Concomitant HIV infection in newly diagnosed multiple myeloma patients is hard to recognise and should be tested for routinely in areas of high endemicity

Background. Over the past three decades much has changed in the treatment and outcomes of patients suffering concurrently from both multiple myeloma (MM) and HIV. While the prevalence of MM appears to be higher in HIV-positive individuals than in those who are uninfected, early recognition of patients suffering from both diseases is difficult and little information is available on their demographics and clinical presentation.Objective. To compare the presenting features of HIV-positive patients diagnosed with MM with those of HIV-negative patients.Methods. A single-centre, retrospective cohort study included 16 HIV-positive and 73 HIV-negative patients diagnosed with MM, in order to compare variables related to the clinical presentation of both conditions.Results. HIV-positive patients presented with MM at a significantly younger age, and had fewer osteolytic lesions, less renal impairment and lower neutrophil counts. Disease stage, gender, pathological fractures, bone marrow plasmacytosis, plasmacytomas and lymphocyte counts were comparable, emphasising the difficulty of identifying these patients. The HIV-positive patients had relatively high CD4 counts and a low prevalence of abnormal Freelite kappa/lambda ratios. All HIV-positive patients presented with paraproteins of the immunoglobulin G (IgG) type, implying a possible relationship between MM and an IgG response to HIV antigens.Conclusions. On the basis of our findings and literature on the treatment of both diseases, we suggest that HIV be tested for routinely in younger MM patients, especially in areas with a high prevalence of HIV. The integration of our results into the sparse knowledge on the role of HIV infection-related MM provides possible new insights into the interaction between these diseases.