Non-crystalline light chain proximal tubulopathy associated with monoclonal gammopathy of renal significance: A case report and review of the literature.
Clin Nephrol
; 99(1): 32-40, 2023 Jan.
Article
em En
| MEDLINE
| ID: mdl-36444974
ABSTRACT
BACKGROUND:
Light chain proximal tubulopathy (LCPT) is a rare M-proteinemia-related nephropathy. Non-crystalline LCPT is even rarer. We herein report an unusual case of renal dysfunction and proteinuria due to κ-restricted and non-crystalline LCPT in a context of monoclonal gammopathy of renal significance (MGRS) without Fanconi syndrome (FS). CASE PRESENTATION A 67-year-old man was admitted for a 2-year history of proteinuria and renal dysfunction. Fanconi syndrome (FS) was not observed. He was noted to have IgG-κ M protein, and the previous bone marrow biopsy revealed that atypical plasma cells accounted for 1.5% of the cells, which did not meet the diagnostic criteria for multiple myeloma. A renal biopsy revealed proximal tubular injury, including increased lysosomes with irregular contours and a mottled appearance without crystalline structure and the accumulation of κ light chains. He was diagnosed with non-crystalline LCPT with MGRS. Concurrently, we reviewed the non-crystalline LCPT cases previously published in the literature. Our patient finally received chemotherapy with a bortezomib and dexamethasone regimen. The patient did not seem to achieve evident nephrological and hematological remission after chemotherapy, but he was in a stable condition.CONCLUSION:
Very few similar cases are reported in the literature. It is considered crucial to enhance our knowledge about these cases to establish the definition of the non-crystalline LCPT entity and allow for early diagnosis. Chemotherapy may not be necessary for all patients to maintain good renal function. Future prospective clinical research studies are necessary.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Paraproteinemias
/
Síndrome de Fanconi
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Nefropatias
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Mieloma Múltiplo
Tipo de estudo:
Risk_factors_studies
/
Screening_studies
Limite:
Aged
/
Humans
/
Male
Idioma:
En
Ano de publicação:
2023
Tipo de documento:
Article