¿Qué hay de nuevo en el tratamiento de amiloidosis por cadenas livianas? Parte 1: cadenas livianas / What is new in light chain amyloidosis treatment? Part 1: lightweight chains

La amiloidosis AL es una enfermedad debida al depósito, en órganos y tejidos, de fibrillas formadas por cadenas livianas producidas de forma patológica por plasmocitos clonales. Su tratamiento actualmente está orientado a erradicar el clon de células plasmáticas; este históricamente se extrapoló de tratamientos disponibles y estudiados para otras discrasias sanguíneas. En el año 2020, el Grupo de Estudio de Amiloidosis (GEA) confeccionó distintas guías de práctica clínica para el tratamiento de la amiloidosis AL. Desde entonces se han publicado ensayos clínicos que arrojan contundencia al conocimiento disponible hasta el momento, y están en desarrollo nuevas líneas de investigación que robustecen y estimulan el estudio en el área. En esta revisión se realiza una actualización de las guías existentes en lo que respecta al tratamiento de la amiloidosis por cadenas livianas.Como evidencia de relevancia, en el último año estuvieron disponibles resultados de ensayos clínicos que respaldan el uso de esquemas basados en daratumumab (un anticuerpo monoclonal anti-CD38+) para pacientes con diagnóstico reciente de amiloidosis AL como primera línea. Además, para el tratamiento de la amiloidosis AL refractaria o recaída, la disponibilidad de bibliografía respaldatoria es escasa y extrapolada del tratamiento del mieloma múltiple; sin embargo, actualmente existe evidencia de calidad para recomendar el uso de ixazomib, un inhibidor de proteosoma reversible por vía oral disponible en la Argentina desde 2020. Por último, se mencionan algunas líneas de investigación con otros anticuerpos monoclonales y terapéuticas basadas en el uso de CAR-T cells. (AU)

AL amyloidosis is a disease caused by the deposit in different organs and tissues of protein fibrils formed by light chains synthetized by pathological clonal plasma cells. Its treatment is currently aimed at eradicating this plasma cell clone and it has been historically extrapolated from available and validated treatments for other blood dyscrasias. In 2020, the Amyloidosis Study Group prepared different clinical practice guidelines for the treatment of AL amyloidosis.Since then, clinical trials have been published that confirm and strengthen the knowledge available up to now, and new lines of research are being developed that stimulate study in the area. In this review, an update of the existing guidelines regarding the treatment of AL amyloidosis is made. As relevant evidence, in the last year, results of clinical trials have been made available that support the use of regimens based on Daratumumab (an anti-CD38+ monoclonal antibody) for patients with newly diagnosed AL amyloidosis as first line therapy. In addition, for the treatment of refractory or relapsed AL amyloidosis, where the availability of supporting literature is scant and extrapolated from the treatment of multiple myeloma, there is currently quality evidence to recommend the use of ixazomib, an oral reversible proteasome inhibitor, only available in Argentina since 2020. Finally, some research lines exploring the efficacy of other monoclonal antibodies and therapeutic experiments based on the use of CAR-T cells are mentioned. (AU)

Manejo ambulatorio de pacientes con amiloidosis cardiaca por cadenas livianas / Outpatient management of patients with cardiac light chain amyloidosis

Resumen La amiloidosis primaria o de cadenas livianas (AL) es la forma más común de amiloidosis y se caracteriza por presentar una población clonal de células plasmáticas que producen una cadena ligera monoclonal de tipo lambda o kappa. En algunos sujetos, dicha cadena se deposita en forma de amiloide en los órganos y tejidos, dando lugar a manifestaciones clínicas, como proteinuria o síndrome nefrótico, miocardiopatía restrictiva y hepatomegalia. Aunque se considera una enfermedad rara, datos recientes sugieren que la amiloidosis cardíaca se subestima como una causa de enfermedades o síndromes cardíacos comunes. En la amiloidosis AL, tanto la respuesta hematológica como la de los órganos después del tratamiento son importantes para mejorar el resultado clínico, especialmente, si mejora la función cardíaca que es uno de los aspectos clave en el pronóstico de la amiloidosis AL. Se presenta el caso y la revisión de un paciente de sexo femenino, de 67 años de edad, que en la pesquisa diagnóstica de anemia e insuficiencia cardiaca (IC) se concluye en el diagnóstico de mieloma múltiple y amiloidosis cardiaca (AC) por depósito de cadenas livianas.

Abstract Primary or light chain (AL) amyloidosis is the most common form of amyloidosis and is characterized by a clonal population of plasma cells that produce a monoclonal lambda or kappa-type light chain, which in some subjects this chain is deposited as amyloid in the organs and tissues, giving rise to clinical manifestations such as proteinuria or nephrotic syndrome, restrictive cardiomyopathy and hepatomegaly. Although considered a rare disease, recent data suggest cardiac amyloidosis is underestimated as cause of common heart diseases or syndromes. In AL amyloidosis, both the hematologic and organ response after treatment, are important to improve clinical outcome. Especially if it improves cardiac function is one of the key aspects in the prognosis of AL amyloidosis. We present the case and review of a 67-year-old female patient, who in the investigation diagnoses anemia and heart failure concludes in the diagnosis of multiple myeloma and cardiac amyloidosis due to light chain deposition.

Una causa olvidada de insuficiencia cardíaca / A forgotten cause of heart failure

Amyloidosis is a low-frequency disease that can cause compromise of different systems. We report a case of heart failure in an 81-year-old woman secondary to amyloidosis, in which the echocardiogram was a valuable diagnostic tool.

Valor diagnóstico de la electroforesis de proteínas y cadenas ligeras libres en suero en el mieloma múltiple / Diagnostic value of serum protein electrophoresis and free light chains in the multiple myeloma's diagnosis

RESUMEN Fundamento: La electroforesis de proteínas y las cadenas ligeras libres en suero son técnicas utilizadas en el diagnóstico del mieloma múltiple. Sin embargo, la utilidad diagnóstica de ambas pruebas puede variar según el método empleado y condiciones reales del medio donde se realicen. Objetivo: Determinar el valor diagnóstico de la electroforesis de proteínas y de las cadenas ligeras libres en suero en el mieloma múltiple. Metodología: Se realizó un estudio retrospectivo de los parámetros electroforesis de proteínas en suero y cadenas ligeras libres en suero a 43 pacientes con diagnóstico de mieloma múltiple por evaluación de la médula ósea. La electroforesis de proteínas se realizó por el método convencional de separación de proteínas sobre papel de acetato de celulosa y para las cadenas ligeras libres se aplicó un ensayo inmunoturbidimétrico en el que se usó un analizador químico (Cobas 311). Se calcularon 7 parámetros que evaluaron la exactitud diagnóstica. Resultados: Todos los parámetros que evaluaron la exactitud diagnóstica estuvieron dentro de los intervalos de confianza en ambas pruebas. Conclusiones: La electroforesis de proteínas y las cadenas ligeras libres en suero son ensayos de gran utilidad en el diagnóstico del mieloma múltiple y se deben utilizar en conjunto para la mayor captación posible de casos.

ABSTRACT Background: Protein electrophoresis and serum free light chains are techniques used in the diagnosis of multiple myeloma. However, the diagnostic utility of both tests may vary according to the method used and the actual conditions of the environment where they are performed. Objective: To determine the diagnostic value of protein electrophoresis and serum free light chains in multiple myeloma. Methodology: A retrospective study of serum protein electrophoresis parameters and serum free light chains was conducted in 43 patients diagnosed with multiple myeloma by bone marrow evaluation. Protein electrophoresis was completed by the conventional method of protein separation on cellulose acetate paper and for free light chains an immunoturbidimetric assay was applied in which a chemical analyzer (Cobas 311) was used. Seven parameters were calculated to evaluate diagnostic accuracy. Results: All parameters assessing diagnostic accuracy were within confidence intervals in both tests. Conclusions: Protein electrophoresis and serum free light chains are very useful assays in the diagnosis of multiple myeloma and should be used in conjunction for the highest possible approval of cases.

Spectrum of renal diseases in the elderly, above age 50

Background: The spectrum of kidney diseases varies in the elderly population with frequent inconsistencies between clinical presentation and histopathological diagnosis. The immunofluorescence (IF) may provide additional information in such situations. Aims: The purpose was to study the spectrum of kidney diseases in patients above 50 years undergoing renal biopsy and utility of light chain (LC) IF in the diagnosis. Settings and Design: This was a retrospective, crosssectional, singlecenter-based study. Material and Methods: The clinical details, histopathological findings, and LC IF pattern in native renal biopsy of patients above 50 years were noted. Statistical Analysis: Continuous variables were presented as mean ± standard deviation (SD). Categorical variables were expressed as frequencies and percentages. Results: A total of 205 patients were included in the study. The most common clinical presentation was acute kidney injury/rapidly progressive glomerulonephritis (AKI/RPGN) (49%). Glomerular diseases (72%) were more common. Crescentic glomerulonephritis (21%) and membranous nephropathy (MN) (19%) were the most common glomerulopathy. LC restriction was observed in LC cast nephropathy (LCCN), primary amyloidosis, and LC also helped in classifying the cases of MPGN-type morphology. Conclusions: AKI/RPGN was the most common indication for renal biopsy in patients above 50 years. Crescentic GN and MN were the frequent glomerular pathology. LC IF is a useful adjunctive tool to classify various renal diseases.

Aplicación de un método in house para el estudio de la esclerosis múltiple / Application of an in-house method for the study of multiple sclerosis

Resumen El método de referencia para el estudio bioquímico de la esclerosis múltiple (EM) es el isoelectroenfoque (IEE) y la evaluación de las cadenas livianas libres (CLL) podría brindar una información adicional de relevancia. Por lo tanto, se propone evaluar la presencia de las CLL y la aplicabilidad de los estados de polimerización en el estudio de la EM. Se puso a punto un método compuesto por una separación electroforética en gel de poliacrilamida al 12,5% con posterior electrotransferencia (PAGE-WB) y se realizó la evaluación de 121 pacientes con sospecha de EM en simultáneo al IEE. Los patrones de PAGE-WB relacionados con la EM fueron el aumento de la concentración de monómeros Kappa o dímeros Lambda en líquido cefalorraquídeo (LCR) en comparación con el suero. Este método tuvo una muy alta significación de asociación con el IEE (p<0,0001) con sensibilidad del 95%, especificidad del 90%, VPP 83% y VPN 97%. La síntesis intratecal de CLL quedó evidenciada por el aumento de intensidad del monómero Kappa y/o el dímero Lambda observado en LCR. La técnica de PAGE-WB para CLL demostró ser un método alternativo para detectar la síntesis intratecal en pacientes con sospecha de EM.

Abstract The reference method for the biochemical study of multiple sclerosis (MS) is isoelectric focusing (IEF) and the evaluation of free light chains (FLC) could provide additional information of relevance. Therefore, it is proposed here to evaluate the presence of FLC and the applicability of the polymerisation states in the study of MS. A method consisting of a 12.5% polyacrylamide gel electrophoretic separation with a subsequent electrotransfer (PAGE-WB) was developed and the evaluation of 121 patients with suspected MS was carried out simultaneously with the IEF. MS-related PAGE-WB patterns were the increase in the concentration of Kappa monomers or Lambda dimers in CSF compared to serum. This method had a very high significance of association with the IEF (p<0.0001) with 95% sensitivity, 90% specificity, 83% PPV and 97% NPV. Intrathecal synthesis of FLC was evidenced by the increased intensity of the Kappa monomers and/or Lambda dimers observed in CSF. The PAGE-WB technique for FLC proved to be an alternative method to detect intrathecal synthesis in patients with suspected MS.

Resumo O método de referência para o estudo bioquímico da esclerose múltipla (EM) é a focalização isoelétrica (IEE) e a avaliação de cadeias leves livres (CLL) poderiam fornecer informações adicionais de relevância. Assim, propõe-se avaliar a presença das CLL e a aplicabilidade dos estados de polimerização no estudo de EM. Foi desenvolvido um método que consiste na separação eletroforética em gel de poliacrilamida a 12,5% com posterior eletrotranferência (PAGE-WB) e a avaliação de 121 pacientes com suspeita de EM foi realizada paralelamente à IEE. Os padrões de PAGE-WB relacionados com a EM foram o aumento na concentração de monômeros Kappa ou dímeros Lambda em líquido cefalorraquidiano (LCR) em comparação com o soro. Este método teve uma associação de significância muito alta com o IEE (p<0,0001) com sensibilidade de 95%, especificidade de 90%, VPP 83% e VPN 97%. A síntese intratecal de CLL foi evidenciada pelo aumento de intensidade do monômero Kappa e/ou dímero Lambda observado em LCR. A técnica PAGE-WB para CLL mostrou-se um método alternativo para detectar a síntese intratecal em pacientes com suspeita de EM.

Serum free light chain level in patients with diabetic kidney disease and its correlation with renal function indexes / 中国医师进修杂志

Objective:To explore the correlation between the level of serum free light chain and renal function indexes in patients with diabetic kidney disease (DKD).Methods:The clinical data of 120 patients with DKD (study group) and 80 patients with simple diabetes (diabetes group) in the Beijing Sixth Hospital from October 2017 to October 2020 were retrospectively analyzed. Five ml of fasting peripheral venous blood were collected, the levels of serum uric acid, creatinine, homocysteine (Hcy) and free light chain (including free light chain κ, free light chain λ, ratio of free light chain κ and free light chain λ and total free light chain) were detected, and the estimated glomerular filtration rate (eGFR) was calculated. The correlation between total free light chain and renal function indexes in patients with DKD was analysis by Pearson method.Results:The free light chain κ, free light chain λ, ratio of free light chain κ and free light chain λ, total free light chain, uric acid, creatinine and Hcy in DKD group were significantly higher than those in diabetes group: (33.92 ± 9.06) mg/L vs. (17.65 ± 4.72) mg/L, (17.52 ± 2.83) mg/L vs. (9.81 ± 3.20) mg/L, 1.93 ± 0.23 vs. 1.80 ± 0.25, (51.44 ± 12.31) mg/L vs. (27.46 ± 7.92) mg/L, (383.69 ± 96.11) μmol/L vs. (345.93 ± 93.94) μmol/L, (117.57 ± 22.39) μmol/L vs. (75.06 ± 14.73) μmol/L and (17.64 ± 5.76) μmol/L vs. (11.66 ± 5.46) μmol/L, the eGFR was significantly lower than that in diabetes group: (103.95 ± 22.58) ml/(min·1.73 m 2) vs. (142.65 ± 26.50) ml/(min·1.73 m 2), and there were statistical differences ( P<0.01). Pearson correlation analysis results showed that serum total free light chain in patients with DKD was positively correlated with uric acid, creatinine and Hcy ( r = 0.707, 0.709 and 0.820; P<0.01), and negatively correlated with eGFR ( r = -0.730, P<0.01). Conclusions:The expression level of serum free light chain is obviously increased in patients with DKD, it has a certain correlation with renal function indexes. It can be used as one of the evaluation indicators for disease monitoring.

The effect and mechanism of astragaloside Ⅳ on lysophosphatidic acid-induced neurite retraction of N1E-115 cells / 国际中医中药杂志

Objective:To observe the effect of astragaloside Ⅳ on lysophosphatidic acid(LPA)- induced neurite retraction of N1E-115 cells and its potential mechanism.Methods:N1E-115 cells were divided into blank group, model group, the low, medium and high dose groups of astragaloside Ⅳ. The blank group and model group was not intervened by astragaloside; while the low, medium and high dose groups were treated with 20,40 and 80 μg/ml astragaloside Ⅳ for 24 h. Each group was cultured with serum-free medium for 12 h. The model group and astragaloside Ⅳ groups were intervened by 40 μmol/L LPA for 10 min. Each group was observed and photographed with the inverted microscope, and the number of neurites in N1E-115 cells was counted by Image J software. The fluorescence expression of recombinant ras homolog gene family member A (RhoA), rho associated coiledcoil protein kinase 2 (ROCK2), phospho-rho associated coiledcoil protein kinase 2 (p-ROCK2) and phospho-myosin light chain 2 (p-MLC2) proteins was detected by immunohistochemistry. Real-time fluorescent quantitative polymerase chain reaction was used to detect the mRNA expression levels of RhoA and ROCK2 ; the protein expression levels of RhoA, ROCK2, p-MLC2 and myosin light chain 2 (MLC2) were detected by Western blotting.Results:Compared with 20 μg/ml astragaloside Ⅳ group, the inhibition rate of neurite retraction in 40 and 80 μg/ml astragalosideⅣ groups increased ( P<0.05). Compared with model group, the average fluorescence intensity of RhoA, p-ROCK2, p-MLC2 in 20, 40, 80 μg/ml astragaloside Ⅳ groups and the ROCK2 average fluorescence intensity in 40 μg/ml astragaloside Ⅳ group were decreased ( P<0.05, P<0.01); the expression of RhoA mRNA (0.89±0.09, 0.41±0.01, 0.09±0.03 vs. 1.50±0.01) and ROCK2 mRNA (0.89±0.09, 0.14±0.01, 0.20±0.01 vs. 1.62±0.17) decreased in 20, 40, 80 μg/ml astragaloside Ⅳ groups ( P<0.05, P<0.01); the ROCK2 protein (0.75±0.06, 0.57±0.02, 0.66±0.01 vs. 1.08±0.02), p-MLC2 protein (1.72±0.03, 1.40±0.04, 1.29±0.03 vs. 2.19±0.11), MLC2 protein (1.13±0.02, 0.68±0.03, 0.75±0.03 vs. 1.60±0.03) in 20, 40, 80 μg/ml astragaloside Ⅳ groups and the RhoA protein (0.35±0.01, 0.40±0.03 vs. 0.57±0.08) in 20, 40 μg/ml astragaloside Ⅳ groups were decreased ( P<0.05, P<0.01). Conclusion:Astragaloside Ⅳ can prevent LPA-induced neurite retraction and promote damaged nerve regeneration. The mechanism may down-regulae the protein expression levels of RhoA, ROCK2, p-ROCK2, p-MLC2 and MLC2 in RhoA-ROCK2 signaling pathway, and inhibite nerve growth cone collapse.

Advances in the application of nuclear medicine imaging in the diagnosis and treatment of systematic light chain amyloidosis / 中华核医学与分子影像杂志

Systematic light chain (AL) amyloidosis is the most common forms of amyloidosis, which manifests as multiple organ system involvement, rapid progress, dire prognosis, difficult therapy and high mortality. Many patients may miss the optimal treatment as a result of not being diagnosed timely. Therefore, early diagnosis and assessment of involved extent of AL are clinical focuses. Related clinical studies have demonstrated that nuclear medicine imaging can be non-invasive in detecting amyloid deposits. It can not only early assess the extent and distribution of amyloid deposits in systemic AL amyloidosis, but also offer the indications for risk stratification, treatment response monitoring and prognosis assessment of the patients, especially for positron amyloidosis-specific tracers, which may have great prospects in the future. This review summarizes the application of nuclear medicine imaging in the systematic AL amyloidosis.

Perfil Clínico, Laboratorial e de Métodos de Imagem na Amiloidose Sistêmica em um Centro de Referência Cardiológico Brasileiro / Clinical, Laboratory, and Imaging Profile in Patients with Systemic Amyloidosis in a Brazilian Cardiology Referral Center

Resumo Fundamento Amiloidose sistêmica é uma doença com manifestações clínicas diversas. O diagnóstico envolve suspeita clínica, aliada a métodos complementares. Objetivo Descrever o perfil clínico, laboratorial, eletrocardiográfico e de imagem no acometimento cardíaco da amiloidose sistêmica. Métodos Estudo de uma amostra de conveniência, analisando dados clínicos, laboratoriais, eletrocardiográficos, ecocardiográficos, medicina nuclear e ressonância magnética. Considerou-se significância estatística quando p < 0,05. Resultados Avaliaram-se 105 pacientes (com mediana de idade de 66 anos), sendo 62 homens, dos quais 83 indivíduos apresentavam amiloidose por transtirretina (ATTR) e 22 amiloidose por cadeia leve (AL). Na ATTR, 68,7% eram de caráter hereditário (ATTRh) e 31,3% do tipo selvagem (ATTRw). As mutações mais prevalentes foram Val142Ile (45,6%) e Val50Met (40,3%). O tempo de início dos sintomas ao diagnóstico foi 0,54 e 2,15 anos nas formas AL e ATTR (p < 0,001), respectivamente. O acometimento cardíaco foi observado em 77,9% dos ATTR e 90,9% dos AL. Observaram-se alterações de condução atrioventricular em 20% e intraventricular em 27,6% dos pacientes, sendo 33,7 % na ATTR e 4,5% das AL (p = 0,006). A forma ATTRw apresentou mais arritmias atriais que os ATTRh (61,5% x 22,8%; p = 0,001). Ao ecocardiograma a mediana da espessura do septo na ATTRw x ATTRh x AL foi de 15 mm x 12 mm x 11 mm (p = 0,193). Observou-se BNP elevado em 89,5% dos indivíduos (mediana 249 ng/mL, IQR 597,7) e elevação da troponina em 43,2%. Conclusão Foi possível caracterizar, em nosso meio, o acometimento cardíaco na amiloidose sistêmica, em seus diferentes subtipos, através da história clínica e dos métodos diagnósticos descritos.

Abstract Background Systemic amyloidosis is a disease with heterogeneous clinical manifestations. Diagnosis depends on clinical suspicion combined with specific complementary methods. Objective To describe the clinical, laboratory, electrocardiographic, and imaging profile in patients with systemic amyloidosis with cardiac involvement. Methods This study was conducted with a convenience sample, analyzing clinical, laboratory, electrocardiographic, echocardiographic, nuclear medicine, and magnetic resonance data. Statistical significance was set at p < 0.05. Results A total of 105 patients were evaluated (median age of 66 years), 62 of whom were male. Of all patients, 83 had transthyretin (ATTR) amyloidosis, and 22 had light chain (AL) amyloidosis. With respect to ATTR cases, 68.7% were the hereditary form (ATTRh), and 31.3% were wild type (ATTRw). The most prevalent mutations were Val142Ile (45.6%) and Val50Met (40.3%). Time from onset of symptoms to diagnosis was 0.54 and 2.15 years, in the AL and ATTR forms, respectively (p < 0.001). Cardiac involvement was observed in 77.9% of patients with ATTR and in 90.9% of those with AL. Alterations were observed in atrioventricular and intraventricular conduction in 20% and 27.6% of patients, respectively, with 33.7% in ATTR and 4.5% in AL (p = 0.006). In the ATTRw form, there were more atrial arrhythmias than in ATTRh (61.5% versus 22.8%; p = 0.001). On echocardiogram, median septum thickness in ATTRw, ATTRh, and AL was 15 mm, 12 mm, and 11 mm, respectively (p = 0.193). Elevated BNP was observed in 89.5% of patients (median 249, ICR 597.7), and elevated troponin was observed in 43.2%. Conclusion In this setting, it was possible to characterize cardiac involvement in systemic amyloidosis in its different subtypes by means of clinical history and the diagnostic methods described.

Daratumumab for the treatment of primary systemic amyloidosis: a multicenter retrospective analysis / 中华内科杂志

Objective:To analyze the efficacy and safety of Daratumumab for the treatment of primary AL light chain systemic amyloidosis.Methods:Twenty one patients who were diagnosed as primary AL light chain systemic amyloidosis and treated with Daratumumab from 7 centers were retrospectively analyzed. Daratumumab was administrated as first line therapy in seven patients and 14 patients with relapsed settings. Hematological response, safety and survival were analyzed.Results:All 7 patients achieved very good partial response (VGPR) or better with first-line application of daratumumab. Three patients died, and the other four achieved organ remission. Among 14 relapsed patients, 2 patients had a difference of free light chain (dFLC) less than 20 mg/L before treatment, and 9 with a dFLC of more than 50 mg/L. All patients reached partial response (PR) or better, including 4 patients with complete response (CR), 3 with VGPR and 2 with PR. The response rate was 100% in 3 patients with dFLC 20-50 mg/L at baseline. The organ remission rate was 50% in patients with heart involvement and 58.3% in patients with kidney impairment. The overall median follow-up period was 5.3 months, and 11 months in surviving patients. One patient died of severe infection and disseminated intravascular coagulation (DIC) with stable amyloidosis. One patient switched to other regimens because dFLC elevated but did not fulfill progressive disease after 2 year application. As to safety, no grade 3/4 infusion reaction developed, and grade 1 infusion reaction occurred in 3 cases during the first infusion. Lymphocytopenia was seen in 75% patients including grade 3 or more in 30% patients.Conclusion:Daratumumab is effective to eliminate serum free light chain in both newly diagnosed and relapsed patients with systemic amyloidosis.

Software for cerebrospinal fluid diagnostics and statistics / Software para el diagnóstico y estadísticas del líquido cefalorraquídeo

Background: In CSF analysis for diagnostics we have knowledge-based software for numerical and graphical data interpretation, but software programs for statistics are scarce. Free, stand-alone software programs that calculate all individual functions of CSF protein analysis and allow the statistical treatment of groups of diseases numerically and graphically are presented for relevant examples. Methods: Diagnosis of an intrathecal synthesis refers to the upper limit of the reference range, Qlim = Qmean +3SD, but statistical evaluation of its frequency is referred to Qmean+2SD. When quantifying intrathecal synthesis for statistics, either the absolute amount (IgGloc) or the relative intrathecal fraction (IgGIF) can be reported with reference to the mean reference curve, Qmean. The free software CSF research Tool for immunoglobulins allows diagnostic and statistic evaluations with Reibergrams and calculation of mean values and standard deviations from disease groups. The software FLC-K statistics for free light chains Kappa offers for diagnostics and statistics the numerical and graphical interpretation basis for statistical processing in exported Excel tables. A free "CSF-App" for Smartphones provides data calculation for diagnostics of single patients with examples of disease-related data patterns. Results: Patients with clinically isolated syndrome (CIS) who were later diagnosed as MS showed no immunological differences to patients initially diagnosed as MS (same mean quantity of intrathecal synthesis in CIS and MS detectable for IgG and FLC-K). The frequently claimed diagnostically higher sensitivity of the FLCK analysis compared to IgG, can be explained by the up to 3-fold higher mean intrathecal fraction of FLC-K, corresponding to a higher frequency in the detection of intrathecal synthesis with FLCK analysis. Conclusions: With a knowledge-based quantification in CSF analysis, supported by knowledge-based software programs, scientifically and diagnostically important results can be obtained(AU)

Introducción: Los programas de software gratuitos y autónomos que calculan todas las funciones individuales del análisis de proteínas del líquido cefalorraquídeo (LCR) y permiten el tratamiento estadístico de grupos de enfermedades de forma numérica y gráfica se presentan como ejemplos relevantes. Métodos: Cuando se cuantifica la síntesis intratecal para la estadística, se puede informar la cantidad absoluta (IgGloc) o la fracción intratecal relativa (IgGIF) con referencia a la curva de referencia media, Qmean. El software gratuito "CSF research Tool" para inmunoglobulinas permite realizar evaluaciones diagnósticas y estadísticas con Reibergrams y calcular los valores medios y las desviaciones estándar de los grupos de enfermedades. El software FLC-K statistics para Free light chains Kappa ofrece para el diagnóstico y la estadística la base de interpretación numérica y gráfica para el procesamiento estadístico en tablas exportadas de Excel. El programa CSF-App para teléfonos inteligentes es gratuito y ofrece el cálculo de datos para el diagnóstico de pacientes individuales con ejemplos de patrones de datos relacionados con enfermedades. Resultados: Los pacientes con síndrome clínico aislado (SCA) que posteriormente fueron diagnosticados como EM no mostraron diferencias inmunológicas con respecto a los pacientes inicialmente diagnosticados como EM (la misma cantidad media de síntesis intratecal en el síndrome clínico aislado y EM detectable para IgG y FLC-K). La sensibilidad más elevada que se afirma con frecuencia en el diagnóstico del análisis de FLC-K en comparación con la IgG, puede explicarse por la fracción intratecal media hasta tres veces mayor de FLC-K, que corresponde a una mayor frecuencia en la detección de la síntesis intratecal con el análisis de FLC-K. Conclusiones: Con la cuantificación en el análisis del LCR se pueden obtener resultados importantes desde el punto de vista científico y diagnóstico(AU)

Acute Renal Failure Due to Cast Nephropathy without Multiple Myeloma

We report a 64 year-man with acute renal failure on top of hischronic renal disease due to diffuse diabeticglomerulosclerosis. Serum creatinine had reached 600umol/L from a baseline of 160 umol/L 4 months ago. Kidneybiopsy revealed diffuse broad casts obstructing the distaltubules with interstitial fibrosis associated with cast’sextravasation. The casts stained positive with kappa and notlambda indicating their monoclonal origin. The patient did nothave evidence of lymphoprolifertive disease and myeloma inparticular with normal skeletal survey and bone marrowtrephine biopsy. Moreover, serum protein and urineelectrophoresis failed to show monoclonal band. Only, directserum testing for free light chain confirmed high Kappa andnormal Lambda levels. The patient already had improved oncorticosteroids and subsequently Melphalan was added.Serum creatinine decreased to 180 umol/L by the end of this6-month treatment. The case illustrates a unique presentationof cast nephropathy without overt lymphoprolifertive disorderand with normal serum as well as urine proteinelectrophoresis. It emphasizes the need for kidney biopsyand/or direct measurement of serum free light chains fordefinitive diagnosis in such covert cases.

Clinicopathological characteristics of renal light chain deposition disease coexisted with cast nephropathy / 中华肾脏病杂志

Objective To investigate the clinicopathological characteristics of renal light chain deposition disease coexisted with cast nephropathy (LCDD&LCN).Methods Patients with LCDD&LCN (n=10),isolated LCDD (I-LCDD,n=21) and isolated LCN(I-LCN,n=17) diagnosed byrenal biopsy in Peking University First Hospital from January 1,2000 to March 31,2018 were enrolled,and all cases were examined by light microscopy,immunofluorescence (IF) (including light chain) and electron microscopy (EM).The semi-quantitative evaluation of the main features of renal pathology was performed.The clinical manifestations and pathological features were reviewed and compared.Results LCDD&LCN was more prevalent in middle-aged males.Nine patients showed acute renal insufficiency with small molecular proteinuria (97.1％) and microscopic hematuria.The hematologic diseases included 9 patients of multiple myeloma.The type of monoclonal light chain in serum and urine by immunofixation electrophoresis showed λ dominant (5/8).By light microscopy,glomerular lesions presented with mild mesangial proliferation in most patients,and only one of them displayed mesangial nodular sclerosis.At the same time,acute tubular injury with light chain casts was the prominent feature,and the clinical manifestations and histological features of LCDD&LCN were similar to that of I-LCN.IF revealed linear staining of monoclonal light chain along the glomerular basement membrane (GBM),tubular basement membrane (TBM) and Bowman's capsule,and also positive in tubular casts.By electron microscopy,diffuse powder-like or granular electron-dense deposits located in the inner side of the GBM,the outer layer of the TBM,renal interstitium and arteriolar walls were observed.Conclusions Patients with LCDD&LCN manifest as acute renal insufficiency,and the majority have multiple myeloma.The pathology of LCDD&LCN possesses the features of both I-LCDD and I-LCN.The IF stain of light chains(κ,λ) and ultrastructural examination by electron microscopy are the inevitable methods for the diagnosis of LCDD&LCN.

Renal tubular P-glycoprotein expression is reduced in plasma cell disorders

BACKGROUND: P-glycoprotein (P-gp) transports many chemicals that vary greatly in their structure and function. It is normally expressed in renal proximal tubular cells. We hypothesized that P-gp expression influences light chain excretion. Therefore, we investigated whether renal tubular P-gp expression is altered in patients with plasma cell disorders. METHODS: We evaluated renal biopsy specimens from patients with plasma cell disorders (n = 16) and primary focal segmental glomerulosclerosis (the control group, n = 17). Biopsies were stained with an anti-P-gp antibody. Loss of P-gp expression was determined semi-quantitatively. Groups were compared for loss of P-gp expression, and clinical variables. RESULTS: P-gp expression loss was more severe in patients with plasma cell disorders than it was in those with glomerulonephritis (P = 0.021). In contrast, clinical and histological parameters including serum creatinine, level of urinary protein excretion, and interstitial fibrosis/tubular atrophy grade were not significantly different between the groups. P-gp expression loss increased with age in patients with plasma cell disorders (P = 0.071). This expression loss was not associated with serum creatinine, the level of urinary protein excretion or the interstitial fibrosis/tubular atrophy grade. There was no significant association between the severity of P-gp expression loss with the types and serum levels of light chains, isotypes and serum immunoglobulin levels. CONCLUSION: Renal tubular P-gp expression is significantly down-regulated in patients with plasma cell disorders characterized by nephrotic range proteinuria. Additional studies are needed to determine whether reintroduction of renal tubular P-gp expression would mitigate the proximal tubular injury that is caused by free-light chains.

Classification of cardiac amyloidosis: an immunohistochemical analysis / 中华病理学杂志

Objective@#To evaluate the sensitivity and specificity of immunohistochemistry (IHC) in the classification of cardiac amyloidosis on endomyocardial biopsy (EMB) and heart allograft.@*Methods@#Twenty cardiac tissues from 19 patients at Fuwai Hospital from January, 1990 to April, 2017 with histopathologic features of amyloidosis and Congo red staining positivity were included. IHC was performed with monoclonal antibodies against AA amyloid and polyclonal antibodies against transthyretin (ATTR), λ-light chain (AL-λ), κ-light chain (AL-κ), ApoAⅠ, ApoAⅡ, ApoA Ⅳ and β2-microglobin. The extent of interstitial staining was evaluated by light microscopy, and three patterns were recognized; these included diffuse pericellular pattern, discrete pericellular pattern, and nodular pattern. Two patterns of vascular deposition were also noted, including arterial pattern and venous pattern. Endocardial involvement was also assessed and recorded.@*Results@#Nineteen cases were divided into three groups according to the pattern of proteins expression in specimens. The first group (5 cases) only showed single protein expression on EMB. The second group (6 cases) showed more than one protein expression, but one of them was intensely stained or any staining of any protein together with ApoA Ⅳ co-staining. The third group (8 cases) also showed more than one protein expression and all of them had intense staining. Amyloid deposits were successfully subtyped as AL-λ, ATTR, AL-κ and ApoAⅠby IHC in the former two groups with the sensitivity of 11/19. In the third group, amyloid deposits could not be subtyped by immunohistochemistry due to their poor specificity. The pericellular pattern tended to favor AL over ATTR amyloidosis and vascular deposition tended to favor ATTR.@*Conclusions@#Amyloid deposits can be reliably subtyped in diagnostic cardiac specimens using IHC. The co-deposition of chaperon proteins, the distribution of amyloid proteins and clinical features are also auxiliary to subtype cardiac amyloidosis.

Primary systemic amyloidosis with chronic diarrhea onset: report of one case and review of literature / 白血病·淋巴瘤

Objective To explore the clinical features, diagnosis and treatment of chronic diarrhea with primary systemic amyloidosis (AL). Methods The clinical experience of an AL patient with chronic diarrhea who was admitted to chinese PLA General Hospital in November 2017 was presented, and the related literature was reviewed. Results The patient was definitely diagnosed as AL with chronic diarrhea onset;after treatment with VCD regimen, the condition was improved obviously and achieved complete remission. Conclusion AL patient with chronic diarrhea onset needs to undergo various detections to make a clear diagnosis and differential diagnosis, and the bortezomib-based treatment scheme can achieve good curative effect.

The value of serum heavy/light chain immunoassay to assess therapeutic response in patients with multiple myeloma / 中华血液学杂志

Objective@#To assess the value of immunoglobulin heavy/light chain (HLC) immunoassay on therapeutic response in patients with multiple myeloma(MM).@*Methods@#A total of 45 newly diagnosed MM patients were retrospectively enrolled in Peking Union Medical College Hospital from 2013 to 2016, whose 115 serum samples were consecutively collected. HLC was tested to evaluate response and compare with other methods for M protein detection.@*Results@#①There were 30 males and 15 females in total of whom the monoclonal immunoglobulin was IgG in 27 (IgGκ∶IgGλ 12∶15) and IgA (IgAκ∶IgAλ 9∶9) in 18. The arerage age of the studied population was 59 (range 43-80) . ② In 34 patients with serum sample at diagnosis, 32 (94.1%) had abnormal HLC ratio (rHLC) while 2 patients with IgG had normal rHLC. The percentages of abnormal rHLC was 81.8% (18/22) at partial response、50.0%(9/18) at very good complete response and 16.0%(4/25) at complete response. ③In 25 patients reaching CR, there were 13 with IgG and 12 with IgA. 4 patients equally split of IgG and IgA had abnormal rHLC at complete response. ④By monitoring the rHLC of some patients consecutively, we found that the remission of rHLC was to some extent behind the remission of SPE and IEF, or even rFLC.@*Conclusion@#Immunoglobulin HLC detection is one feasible method for minimal residual disease detection.

The value of serum heavy/light chain immunoassay to assess therapeutic response in patients with multiple myeloma / 中华血液学杂志

Objective: To assess the value of immunoglobulin heavy/light chain (HLC) immunoassay on therapeutic response in patients with multiple myeloma(MM). Methods: A total of 45 newly diagnosed MM patients were retrospectively enrolled in Peking Union Medical College Hospital from 2013 to 2016, whose 115 serum samples were consecutively collected. HLC was tested to evaluate response and compare with other methods for M protein detection. Results: ①There were 30 males and 15 females in total of whom the monoclonal immunoglobulin was IgG in 27 (IgGκ∶IgGλ 12∶15) and IgA (IgAκ∶IgAλ 9∶9) in 18. The arerage age of the studied population was 59 (range 43-80) . ② In 34 patients with serum sample at diagnosis, 32 (94.1%) had abnormal HLC ratio (rHLC) while 2 patients with IgG had normal rHLC. The percentages of abnormal rHLC was 81.8% (18/22) at partial response、50.0%(9/18) at very good complete response and 16.0%(4/25) at complete response. ③In 25 patients reaching CR, there were 13 with IgG and 12 with IgA. 4 patients equally split of IgG and IgA had abnormal rHLC at complete response. ④By monitoring the rHLC of some patients consecutively, we found that the remission of rHLC was to some extent behind the remission of SPE and IEF, or even rFLC. Conclusion: Immunoglobulin HLC detection is one feasible method for minimal residual disease detection.

Amiloidosis AL: reporte de caso clínico en adulto mayor / Amyloidosis AL: clinical case report in elderly

Se presenta el caso clínico de una paciente de 63 años, con indicación de tiroidectomía total, a causa de un bocio multinodular con infiltrado neoplásico folicular. La evolución posquirúrgica fue tórpida y se caracterizó por la presencia de insuficiencia cardiaca aguda, hepatomegalia, neuropatía periférica y equimosis periorbitaria, condiciones clínicas sugerentes de amiloidosis, la que fue confirmada por medio de estudios como amiloidosis de cadenas ligeras (AL).

We present the clinical case of a 63-year-old patient, with indication of total thyroidec-tomy, due to a multinodular goiter with a follicular neoplastic infiltrate. Postoperative evolution was torpid and was characterized by the presence of acute heart failure, hepatomegaly, peripheral neuropathy and periorbital ecchymosis, clinical conditions suggestive of amyloidosis, which was confirmed by studies such as amyloidosis of light chains (AL).