Abstract: SA-PO219
Leukocyte Chemotactic Factor 2 (ALECT2)-Associated Kidney Amyloidosis in New Mexico: A Report of Two Cases and a Call for Attention to Epidemiologic Surveillance
Session Information
- Onconephrology: Kidney Outcomes during Cancer Treatment and Nephropathies
October 26, 2024 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Onconephrology
- 1700 Onconephrology
Authors
- Vasquez-Rios, George, Glomerular Disease Center, Renal Medicine Associates, Albuquerque, New Mexico, United States
- Avila, Paul Brandon, University of New Mexico Health Sciences Center, Albuquerque, New Mexico, United States
- Garcia, Pablo, University of New Mexico Health Sciences Center, Albuquerque, New Mexico, United States
Introduction
LECT2-associated renal amyloidosis (ALECT2) was first described in the United States, predominantly affecting patients of Hispanic descent. The mechanisms, epidemiological drivers, and long-term prognosis of this disease remain poorly understood. Here, we present two cases from our GN clinic involving patients of Mexican descent residing in New Mexico for over 50 years.
Case Description
Case 1: An 80-year-old male with moderate CKD (sCr: 2 mg/dL), mild albuminuria (450 mg/g), hematuria. He presented with mild hypertension (142/60) and trace edema. Case 2: A 69-year-old male with moderate-severe CKD (serum Cr: 2.4 mg/dL), mild albuminuria (700 mg/g), hematuria. Both patients were referred by their PCPs due to slowly progressive kidney function decline over a span of 10-15 years. One of the patients had background of DM2. Comprehensive GN work-up showed mildly elevated ANA and ESR levels, no M-protein, negative SPEP/UPEP, and normal serum free light chain ratio. Bone marrow biopsy and imaging found no cell clonality or evidence of malignancy or clear source of hematuria. Given the concern for potential inflammatory versus MGRS presentations kidney biopsies were obtained. In both cases, kidney biopsies revealed amyloid deposits in glomeruli, blood vessel walls, and tubular interstitium with characteristic green birefringence. Immunohistochemical staining for amyloid A was negative. However, staining with anti-LECT2 antibody by an antigen retrieval technique at pH2 was positive; confirming the diagnosis of ALEC2 renal amyloidosis. Given the absence of cancer, asymptomatic presentation, and slowly progressive nature, we opted for conservative management (ACEi). On follow-up, both patients showed relatively stable CKD.
Discussion
The pathogenesis of ALECT2 remains to be elucidated. It is unclear if genetic or epidemiological factors contribute to its onset predominantly in Hispanics, and whether it can recur in post-kidney transplant patients, considering its major production in the liver. The preferred management includes RAS blockers. These cases highlight the need for increased epidemiologic surveillance and research into the mechanisms and prognosis of ALECT2. Given its prevalence in Hispanic populations, further studies are warranted to understand potential genetic or environmental factors influencing this condition.