Concordance rate between oligoclonal bands and the Kappa index in patients with suspected multiple sclerosis (MS) / Concordância entre bandas oligoclonais e o índice Kappa em pacientes com suspeita de esclerose múltipla (EM)

Abstract Background Oligoclonal bands (OCBs) and Kappa free light chains (FLCs) in the cerebrospinal fluid (CSF) are sensitive markers of intrathecal immunoglobulin (Ig)G synthesis in patients with multiple sclerosis. Objective To evaluate the concordance rate between OCBCs and the Kappa index (KI) in patients with suspected multiple sclerosis (MS). Methods Patients with suspected MS were referred to a specialized CSF laboratory as part of their diagnostic investigation. Paired CSF and serum samples were collected and submitted to detection of OCBs and determination of the KI. Positive and negative results were determined with both methods, and the percentage of agreement between them was established. Results In total, 171 serum and CSF samples from 171 patients were included in the analysis. The mean age of the patients was of 40 ± 14.2 years; 18.9% of them were male, and 81.1% were female. The OCBs and KI presented concordant results in 161 (94.2%) samples: in 74 (43.3%), both were positive, and in 87 (50.9%), both were negative. In 10 cases, the results were discrepant: KI positive/OCB negative in 8 and OCB positive/KI negative in 2 cases. Conclusion The KI and OCBs presented high concordance level. Currently, the detection of OCBs in the CSF is the standard method for MS diagnosis, but it is time-consuming, and its visual interpretation can be difficult. The results suggest that the KI is a good alternative for the detection of intrathecal immunoproduction in cases of suspected MS.

Resumo Antecedentes Bandas oligoclonais (BOCs) e cadeias leves de imunoglobulina (free light chains, FLCs, em inglês) Kappa no líquido cefalorraquidiano (LCR) são marcadores sensíveis da síntese intratecal de imunoglobulina (Ig)G em pacientes com esclerose múltipla (EM). Objetivo Avaliar a taxa de concordância entre BOCs e o índice Kappa (IK) em pacientes com suspeita de EM. Métodos Pacientes com suspeita de EM foram encaminhados a um laboratório especializado em LCR como parte de sua investigação diagnóstica. Amostras pareadas de LCR e soro foram coletadas e investigadas quanto à presença de BOCs e submetidas à determinação do IK. Resultados positivos e negativos foram determinados com ambos os métodos, e estabeleceu-se o percentual de concordância entre eles. Resultados Ao todo, 171 amostras de soro e LCR de 171 pacientes foram incluídas na análise. A média de idade dos pacientes foi de 40 ± 14,2 anos; 18,9% deles eram do sexo masculino, e 81,1%, do sexo feminino. Resultados concordantes entre as BOCs e o IK foram observados em 161 (94,2%) amostras: em 74 (43,3%), ambos foram positivos, e em 87 (50,9%), ambos foram negativos. Em 10 casos, os resultados foram discrepantes: IK positivo/BOC negativo em 8, e BOC positivo/IK negativo em 2. Conclusão Observou-se alto nível de concordância entre o IK e as BOCs. A detecção de BOCs no LCR é atualmente o método padrão para o diagnóstico de EM, mas é demorado, e sua interpretação visual pode ser difícil. Os resultados sugerem que o IK pode ser uma alternativa para a detecção de imunoprodução intratecal em casos de suspeita de EM.

The significance of serum light chain ratio in the diagnosis of multiple myeloma and primary nephritic / 中国医师杂志

Objective To explore the clinical value of serum κ/λ ratio in the differential diagnosis of multiple myeloma (MM) and primary nephritic,and to explore its relationship with MM other laboratory markers.Methods We obtained 88 cases of MM patients with serotyping by immunofixation and 109 cases of primary nephritic patients.In accordance with the composition of protein M in immunofixation electrophoersis (IFE),88 patients were divided into 4 groups:IgGκ,IgGλ,IgAκ and IgAλ.In addition,45 serum samples of health examination were collected as control samples.The levels of serum IgG,IgA,IgM,light chain κ and λ in each group were tested by immune turbidimetry,and κ/λ ratio was calculated.The levels of serum β2-microglobin (β2-MG),albumin (ALB),serum urea (BUN),creatinine (CRE),and M protein percentage were also detected.Results (1) In MM group,there was no significant difference of sex and International Staging System (ISS) stages between each type(P ＞ 0.05),while there was significant difference in age distribution between each type (P ＜ 0.05).(2) Compared to control,the levels of se-rum light chain κ,κ/λ ratio,and matched Ig were significantly higher and the level of light chain λ and other Ig were significantly lower in κ typed MM patients,while the levels of serum light chain λ were significantly higher and the levels of serum light chain κ,and κ/λ ratio were significantly lower in λ typed MM patients(P ＜0.01).The levels of light chain κ,λ,and IgG in primary nephritic patients were significantly lower than control(P ＜0.01),while there was no significant difference in κ/λ ratio between two group (P ＞ 0.05).There were also significant difference of light chain,Ig,BUN and CRE levels between MM patients and primary nephritic patients (P ＜ 0.05).(3) The κ/λ ratio correlated with serum ALB (r =-0.264,P =0.013) and β2-MG (r =0.235,P =0.040) levels in MM.Conclusions Serum levels of light chain κ,λ,and κ/λ ratio have great significance in the differential diagnosis of multiple myeloma and primary nephritic.The κ/λ ratio correlated with several tumor markers in MM progresses,rendering it as a promising method for diagnosis and prognosis monitoring of MM.

A case of Fanconi syndrome accompanied by crystal depositions in tubular cells in a patient with multiple myeloma

Fanconi syndrome (FS) is a rare condition that is characterized by defects in the proximal tubular function. A 48-year-old woman was admitted for evaluation of proteinuria. The patient showed normal anion gap acidosis, normoglycemic glycosuria, hypophosphatemia, and hypouricemia. Thus, her condition was compatible with FS. The M peak was found behind the beta globulin region in urine protein electrophoresis. Upon bone marrow examination, we found that 24% of cells were CD138+ plasma cells with kappa restriction. From a kidney biopsy, we found crystalline inclusions within proximal tubular epithelial cells. Thereafter, she was diagnosed with FS accompanied by multiple myeloma. The patient received chemotherapy and autologous stem cell transplantation, and obtained very good partial hematologic response. However, proximal tubular dysfunction was persistent until 1 year after autologous stem cell transplantation. In short, we report a case of FS accompanied by multiple myeloma, demonstrating crystalline inclusion in proximal tubular cells on kidney biopsy.

Plasmacytoma of the orbit involving lacrimal gland with secondary transformation into multiple myeloma: case report / Plasmocitoma da órbita envolvendo glândula lacrimal com transformação secundária para mieloma múltiplo: relato de caso

The authors present a rare case of plasmacytoma of the orbit involving lacrimal gland with secondary transformation into multiple myeloma in a 42-year-old woman. The lesion was surgically removed and analyzed. Histopathological examination with immunostaining revealed it to be positive for immunoglobulin G and Kappa chains, demonstrating monoclonality. However, no abnormality was observed on serum electrophoresis, skeletal survey and bone marrow aspiration. Therefore, the tumor was diagnosed solitary plasmacytoma of bone. The patient was treated with external beam radiotherapy and has remained disease free for 5 years and 6 months until 2007, when she presented a pathological fracture due to multiple myeloma. Extensive medical work-up to rule out multiple myeloma or other malignant lymphoproliferative conditions involving orbit or ocular adnexa is needed when the diagnosis of solitary plasmacytoma of bone is suspected because treatment and prognosis are very different.

Os autores relatam um raro caso de plasmocitoma da órbita envolvendo glândula lacrimal com transformação secundária para mieloma múltiplo em uma paciente de 42 anos. A lesão foi removida cirurgicamente e o exame anatomopatológico, aliado à imuno-histoquímica, revelou positividade para imunoglobulina G e cadeias leve tipo Kappa. Após extensa avaliação sistêmica, nenhuma anormalidade foi observada, sendo feito o diagnóstico de plasmocitoma solitário ósseo. A paciente foi submetida à radioterapia, permanecendo livre da doença por 5 anos e 6 meses até 2007, quando apresentou uma fratura patológica devido à infiltração plasmocitária na coluna lombar, sendo feito diagnóstico de mieloma múltiplo. Uma vez que o plasmocitoma solitário ósseo pode ser a primeira manifestação do mieloma múltiplo, esses pacientes necessitam de adequado diagnóstico e seguimento a longo prazo, pois o tratamento e prognóstico dessas duas condições é diferente.