Poliarteritis microscópica en un paciente con esclerosis sistémica / Microscopic polyangiitis in a patient with systemic sclerosis

La coexistencia de esclerosis sistémica (ES) y vasculitis se ha comunicado en pocas ocasiones. Presentamos a un paciente de 65 años, con ES limitada diagnosticada 6 años antes, que desarrolló una glomerulonefritis necrosante focal con proliferación extracapilar asociada a anticuerpos anticitoplasma de neutrófilo con patrón perinuclear (p-ANCA) de especificidad antimieloperoxidasa (anti-MPO) en ausencia de exposición a la D-penicilamina(AU)

The coexistence of systemic sclerosis (SSc) and vasculitis has been infrequently reported. We present a 65-year-old man who, 6 years previously, had been diagnosed with limited SSc, and who developed a focal segmental necrotizing crescent glomerulonephritis associated with perinuclear antineutrophil cytoplasmic antibodies with antimyeloperoxidase specificity in the absence of Dpenicillamine exposure(AU)

[Microscopic polyangiitis in a patient with systemic sclerosis]. / Poliarteritis microscópica en un paciente con esclerosis sistémica.

The coexistence of systemic sclerosis (SSc) and vasculitis has been infrequently reported. We present a 65-year-old man who, 6 years previously, had been diagnosed with limited SSc, and who developed a focal segmental necrotizing crescent glomerulonephritis associated with perinuclear antineutrophil cytoplasmic antibodies with antimyeloperoxidase specificity in the absence of Dpenicillamine exposure.

Determinación inmunonefelométrica de cadenas ligeras libres de inmunoglobulinas en orina / Measurement of free light chains inmunoglobulin in urine by a nephelometric inmunoassay

El método se basa en la reacción de inmunoprccipritacion en [ase líquida, con antisueros específicos absorbidos anti-kaprpa y anti—lambda fibre, de NSC (New Scientific Campany).La.s inmnunocomplejos se cuantificaron con un nefelémetro BNA (Beliring Diagnostic), realizándose condiction antisue ros estudios de precisión, linealidad y comparación con otro método. Se obtuvieron CV intraseriales menores del 5%, exceptuando lambda libre a concentración baja (2,8%). Los análisis resultaron lineales hasta una concentración de 300 mg/dl de Kappa libre y de 150 mg/dl. de lambda libre. Se compararon los resultados de Kappa y lamdba libre (NSC) con los de kappa y lambda total (antisueros de Behiring Diagnostic), observándose que los valores obtenidos con orinas normales eran menores que los cut off asignados (≤4,5 K total, ≤2,6 L total, ≤1K libre, ≤0,7 L libre). Las orinas con cadenas ligeras libres policlonales presentaron uno o más resultados mayores que los cut off y las orinas con proteínas Bence Jones mostraron todos los valores más latos de los cut off (AU)

The procedure is based on inmunoprecipitin reactions in a fluid phase of free light chains with adsorbed aintisera, specific for free kappa and lambda chains, of New Scientific Company (NSC). The resulting inmunocomplexes were quantified with a BNA nephelometer (Behring Diagnostic), we have performed studies of reproducibility, linarity and method comparison. Within-run coefficients of variation (CV) were <5% except for free kappa chains at high concentration (CV =12,7%); between-run CV was 2,8% for free lambda chains at low concentration and >5% for the rst the samples. The assays were linear up to concentrations of 300 mg/dl and 150 mg/dl and 150 mg/dl for free Kappa and Lambda chains, respectively. The results for total kappa and lambda chains (Behring) were compared with those for free kappa and lambda (NSC). We have found that normal urines gave concentrations below the cup off values with both antisera (<4,5 mg7del for free kappa, <0,7 mg/dl for free lambda); urines with polychonal light chains showed one or more pathological results, and above the cut off values in all the cases for urines with Bence-Jones proteins (kappa or lambda) (AU)

Rapid turbidimetric determination of serum C3c and C4 by end point centrifugal analysis.

An end point turbidimetric method for the determination of C3c and C4 in serum using a centrifugal analyzer (Cobas Bio) is described. Several analytical factors were evaluated -pH, temperature, PEG and antibody concentration. Wide variations of temperature and pH did not significantly affect the turbidimetric reaction. A 20 g/L PEG concentration and 25-fold antiserum dilution were found satisfactory for the analysis. Precision of the assay was good and comparison with a RID method yielded an r value of 0.97. The procedure is simple and reliable.