BACKGROUND: Multiple myeloma (MM) is a malignant disorder characterized by monoclonal differentiated plasma cells. While it is more commonly diagnosed in elderly individuals, it can also affect younger populations, though with a lower incidence.
METHODS: Here, we present the case of a 32-year-old woman diagnosed with IgA lambda MM. She presented with fatigue, nausea, acute kidney injury (AKI) with a rapid increase in creatinine, and anemia. A kidney biopsy was done to rule out a rapidly progressive glomerular disease and a diagnosis was thus reached. A genetic workup revealed t(14;16) translocation and an extra copy of TP53. The patient received aggressive intravenous steroids and intravenous fluid resuscitation, resulting in an improvement in renal function. Treatment with daratumumab in combination with bortezomib, thalidomide, and dexamethasone was initiated and well tolerated. Despite the generally poor prognosis of IgA MM, our case emphasizes the importance of considering MM in young patients with unexplained kidney injury.
CONCLUSIONS: Early recognition and prompt intervention are essential in managing MM patients, especially in those with high-risk cytogenetic abnormalities. This case serves as a reminder for clinicians to maintain a high index of suspicion for MM, even in younger populations, when presented with unexplained kidney injury.

暂无摘要。

Less than 2% of all symptomatic multiple myeloma (MM) has immunoglobulin D (IgD) as monoclonal protein. Biclonal gammopathy is much rarer. At the time of diagnosis, disease is often in advanced stage, including renal failure, anemia, hypercalcemia and lytic bone lesions. Due to the rarity of myeloma itself, but also due to the fact that anti-IgD antisera is not used in routine practice, there are only a few reports of IgD MM described in the literature. This case report describes a patient with IgD lambda MM with anemia and renal failure. Anemia, renal failure, and > 80 percent plasma cells in bone biopsy in our patient with IgD lambda MM meets International Myeloma Working Group criteria for diagnosis of MM. The patient clinical course was similar to other patients with IgD MM. The final result of serum protein immunofixation (s-IFE) showed IgD lambda and free lambda monoclonal bands. To prevent misdiagnosis, it is necessary to use anti-IgD and anti-IgE antisera whenever the serum protein immunofixation with IgA, IgM, IgG, kappa and lambda antiserums shows a kappa or lambda monoclonal band without monoclonal band in heavy chain.

暂无摘要。

Several previous case reports have shown that patients with immunoglobulin D (IgD) multiple myeloma (MM) can be withdrawn from hemodialysis, however, the characteristics that can predict withdrawal in these patients have not yet been elucidated. A 57-year-old Japanese woman required hemodialysis because of renal dysfunction due to IgD-λ and Bence Jones protein-λ MM. Bortezomib-based chemotherapy nine days after admission led to her withdrawal from hemodialysis on Day 50. In our case-based review, younger age and early initiation of bortezomib-based chemotherapy emerged as possible predictors of successful hemodialysis withdrawal.

BACKGROUND: CSF free light chains help diagnose multiple sclerosis, but no data is available on the Asian population. Our objective was to study the diagnostic utility of CSF free light chains for diagnosing multiple sclerosis in Indian patients.
METHODS: Prospective multicentric case-control study. Cases included those who were tested for oligoclonal bands and fulfilled the modified McDonald criteria 2017 for multiple sclerosis and clinically isolated syndromes. Those tested for oligoclonal bands (OCB) but with other diagnoses- inflammatory and non-inflammatory were included as controls. Clinical details were collected from electronic medical records. CSF and serum kappa and lambda free light chains were measured, apart from oligoclonal bands, immunoglobulin, and albumin in paired serum and CSF samples.
RESULTS: There were 70 patients (31 cases and 39 controls). The mean age was 43.41(SD 16.073) years, and 43(61.4%) were females. CSF kappa showed highest specificity 97.4%, at a cut off 2.06 mg/L (sensitivity 71%) and highest sensitivity 90.3%, at a cut off 0.47 mg/L (specificity 79.5%). Best balance of sensitivity and specificity for CSF kappa was seen at a cut-off of ≥ 0.63 mg/L {sensitivity 87·1 (CI - 70.17-96.37), and specificity 87·18 (CI -72.57-95.70)}. The ratio of Kappa/lambda showed highest specificity of 100%(similar to OCB) with a sensitivity of 71% at a cut off of 1.72. The ratio of sum of kappa and lambda light chains, and Qalb (∑CSF FLC/Qalb), showed the highest specificity (94.87%)among the blood brain barrier corrected ratios.
CONCLUSIONS: This study showed that the diagnostic utility of CSF kappa was comparable to OCB to diagnose multiple sclerosis in sensitivity, but not specificity, so can be a screening test before testing for OCB in our population.

BACKGROUND: We report a case of a patient with immunoglobulin A multiple myeloma associated with a masked kappa light chain. Serum immunofixation showed a monoclonal band in the IgA heavy chain lane without corre-spondence with the light chain and a monoclonal band in total kappa light chain lane without correspondence with the heavy chain.
METHODS: To distinguish between heavy chain disease and immunoglobulin with \"masked\" light chains, two tubes containing the patient\'s serum were incubated with a very high concentration of anti-total kappa and anti-total lambda antisera for 48 hours at 4°C in order to facilitate immunoprecipitation of the involved light chain. After centrifugation, the supernatant was analyzed by using the IFs method on the Hydrasys 2 Scan Focusing Sebia® without dilution. Then we applied the anti-IgA, anti-total kappa and anti-total lambda antisera.
RESULTS: The serum immunofixation test of the sample treated with a high concentration of anti-total kappa showed the disappearance of the monoclonal bands corresponding to IgA heavy chain lane and kappa light chain lane, indicating that precipitation had occurred and that the IgA did have kappa light chains that could not be detected by the standard immunofixation protocol. The serum immunofixation test of the sample treated with anti-total lambda showed the disappearance of the polyclonal background in lambda light chain lane, confirming that the precipitation with lambda light chains according to the previously mentioned protocol has done well.
CONCLUSIONS: This case illustrates some of the difficulties encountered and the corrective actions that can be taken for the detection of immunoglobulins with masked light chains.

Typically, myeloma cells express a monoclonal immunoglobulin (Ig), either heavy or light chain. Here, we present a case of multiple myeloma with clonal dual expression of kappa and lambda light chain in a 74-year-old woman. Awareness of rare biphenotypic myeloma is important for proper diagnostic workup. A 74-year-old woman underwent hip replacement with an incidental finding of 20% plasma cells in the femoral head. Subsequent bone marrow biopsy also showed about 30% of plasma cells negative for CD20, CD56, and CD117. Immunohistochemistry (IHC) and in situ hybridization studies showed a mixture of kappa and lambda plasma cells. Flow cytometry showed ambiguous results for cytoplasmic Ig light chains kappa and lambda. However, cyclin D1 was highly expressed by plasma cells, and increased free kappa light chains were identified in serum. Further investigation by double IHC demonstrated co-expression of kappa and lambda light chains in the same cells. Fluoresces in situ hybridization studies were positive for t(11;14)(q13;q32) and the deletion 13q. Since its first description by Taylor and Burns in 1974, the demonstration of restricted cytoplasmic Ig light chain expression by immunohistochemistry is 1 of the basic tools for corroborating clonality of the plasma cells in tissue biopsy. IHC results in myeloma with dual expression of Ig light chains may suggest polyclonal plasma cell population, especially when plasma cells do not form sheets in the bone marrow. In an appropriate clinical setting, other investigations are needed to exclude plasma cell neoplasm, even with seemingly \"polytypic\" results by IHC.

IgD myeloma is an extremely rare haemopathy with severe clinical presentation. It can be confused with non-secretory or free light chain myeloma. We here report the case of a 72-year old female patient presenting with bone pain and diffuse ecchymosis and deterioration of her general condition. Laboratory tests showed monoclonal gammopathy associated with severe acute renal failure and low total protein (TP) (48%) with factor X deficiency. Etiological assessment confirmed the diagnosis of IgD lambda myeloma stage IIIb, according to Durie and Salmon, International Staging System (ISS) score III unfavorable cytogenetics. Patient\'s outcome was favorable after treatment with proteasome inhibitor, anti-CD 38 and corticosteroid therapy. Adequate treatment of IgD myeloma, using new therapeutic approaches and hematopoietic stem cell autotransplantation, can improve the prognosis.

淀粉样变性临床罕见，可累及心、肝、肾、周围神经、胃肠道及皮肤软组织等多种器官。其临床表现复杂不典型，缺乏特异性，现报道1例以腹痛为首发表现的轻链-λ型原发性淀粉样变性，以期加强医生对此病的认识，减少误诊和漏诊。.