Proteinuria predicts relapse in adolescent and adult minimal change disease

OBJECTIVE: This study sought to outline the clinical and laboratory characteristics of minimal change disease in adolescents and adults and establish the clinical and laboratory characteristics of relapsing and non-relapsing patients. METHODS: We retrospectively evaluated patients with confirmed diagnoses of minimal change disease by renal biopsy from 1979 to 2009; the patients were aged >13 years and had minimum 1-year follow-ups. RESULTS: Sixty-three patients with a median age (at diagnosis) of 34 (23-49) years were studied, including 23 males and 40 females. At diagnosis, eight (12.7%) patients presented with microscopic hematuria, 17 (27%) with hypertension and 17 (27%) with acute kidney injury. After the initial treatment, 55 (87.3%) patients showed complete remission, six (9.5%) showed partial remission and two (3.1%) were nonresponders. Disease relapse was observed in 34 (54%) patients who were initial responders (n = 61). In a comparison between the relapsing patients (n = 34) and the non-relapsing patients (n = 27), only proteinuria at diagnosis showed any significant difference (8.8 (7.1-12.0) vs. 6.0 (3.6-7.3) g/day, respectively, p = 0.001). Proteinuria greater than 7 g/day at the initial screening was associated with relapsing disease. CONCLUSIONS: In conclusion, minimal change disease in adults may sometimes present concurrently with hematuria, hypertension, and acute kidney injury. The relapsing pattern in our patients was associated with basal proteinuria over 7 g/day.

¿Existe un síndrome nefrótico corticosensible con lesión mínima hereditario? / Is there a corticosensitive nephrotic syndrome with a hereditary minimal lesion?

Se presenta una revisión de las características hereditarias, presentación clínica y pronóstico de los síndromes nefróticos hereditarios que se han descubierto en los últimos años. La mayoría de los estudios están relacionados con síndromes nefróticos hereditarios con lesiones hísticas variadas y mala respuesta al tratamiento. Las mutaciones más frecuentes se producen en los genes NPHS2, NPHS1, WT1 y LAMB2, que producen glomeruloesclerosis focal segmentaria, síndrome nefrótico de tipo finés (enfermedad microquística), esclerosis mesangial difusa y síndrome de Pierson. También se han descrito mutaciones en los genes alfa-actinina 4 y TRPC6, las cuales producen síndrome nefrótico con glomeruloesclerosis focal de comienzo en el adulto. Se ha demostrado la presentación de un síndrome nefrótico familiar con lesión mínima y buena respuesta a los tratamientos, que parece ser producido por algún gen que puede codificar un factor desconocido, cuyo locus es 2p12-p13.2. Se han demostrado casos de síndrome nefrótico familiar que pueden tener patrones hereditarios autosómicos dominantes o recesivos, con evolución similar a la de sus progenitores o hermanos y que se corresponden con respuesta al tratamiento del síndrome nefrótico idiopático con lesión mínima. Se necesita continuar profundizando en el estudio de estos pacientes para precisar las distintas formas de herencia y el gen o genes involucrados en este síndrome nefrótico.

A review of the hereditary characteristics, clinical presentation, and prognosis of the hereditary nephrotic syndromes discovered in the last years is presented. Most of the studies deal with hereditrary nephrotic syndromes with varied tissue lesions and a poor response to treatment. The most frequent mutations are produced in NPHS2, NPHS1, WTI, and LAMB2 genes that produce focal segmental glomerulonephritis, nephrotic syndrome of the Finish type (microcystic disease), diffuse mesangial sclerosis, and Pierson’s syndrome. Mutations in á-actinin 4 and TRPC6 genes causing nephrotic syndrome with onset focal glomerulonephritis mainly in adults have also been described. The presentation of a family nephrotic syndrome with minimal lesion and good response to treatment has been documented. It seems to be produced by some gene that may codify an unknown factor, whose locus is 2p12-p13.2. Cases of family nephrotic syndrome that may have dominant or recessive autosomal hereditary patterns with a similar evolution to that of the progenitors or siblings, and that correspond with the response to the treatment of idiopathic nephrotic syndrome with minimal lesion have been demosstrated. It is necessary to go deep into the study of these patients to determine the different forms of inheritance, and the gene or genes involved in this nephrotic syndrome.