Histopathology. 2026 Jul 31. doi: 10.1111/his.70242. Online ahead of print.
ABSTRACT
AIMS: Monoclonal gammopathy-associated kidney lesions typically present with a single pathological pattern, but the coexistence of multiple patterns in the same patient is rare and poorly characterized. This study aimed to delineate the clinicopathological spectrum and outcomes of these complex cases.
METHODS AND RESULTS: Twenty-three patients with coexistent pathological patterns were identified from native kidney biopsies. The most frequent combinations were light chain cast nephropathy (LCCN) with light chain deposition disease (LCDD) (34.8%), followed by LCCN with light chain amyloidosis (AL) (21.7%) and LCCN with light chain proximal tubulopathy (LCPT) (21.7%). Multiple myeloma was the predominant underlying haematological disorder (87.0%). Compared with isolated AL, the LCCN+AL group showed more severe acute tubular injury and chronic tubulointerstitial damage (both P < 0.05). The LCCN+LCDD group exhibited more severe acute injury but milder chronic fibrosis than isolated LCDD (P < 0.05). The LCCN+LCPT group had the most favourable prognosis, whereas the LCCN+AL group had the worst, with a median survival of only 32 months and significantly higher mortality than isolated LCCN, isolated AL and LCCN+LCPT groups (all P < 0.05).
CONCLUSIONS: Monoclonal gammopathy-associated kidney lesions with coexistent pathological patterns represent a highly heterogeneous entity with distinct features and varied prognoses. The combination of LCCN with AL identifies a particularly high-risk group. Kidney biopsy is crucial for precise classification and prognosis assessment.
PMID:42533743 | DOI:10.1111/his.70242