Characteristics of Engraftment Syndrome following Autologous Stem Cell Transplantation in Light Chain Amyloidosis with Renal Involvement

Acute kidney injury during autologous stem cell transplantation in light chain amyloidosis with kidney involvement and their impact on prognosis

Acute kidney injury (AKI) is a complication related to important organ dysfunction during autologous stem cell transplantation (ASCT) in light chain (AL) amyloidosis. This study aims to validate the risk factors of AKI during different periods of ASCT and the impact of AKI on long-term outcomes. 302 patients with AL amyloidosis and kidney involvement who underwent ASCT were included. The procedures from stem cell mobilization to 30 days after transplantation were categorized into four periods: Period 0 (stem cell mobilization and harvest), Period 1 (preparation), Period 2 (conditioning and transplantation), and Period 3 (engraftment). The incidence of AKI during ASCT was 27.15% (0.66% in Period 0, 6.62% in Period 1, 15.23% in Period 2, and 6.95% in Period 3). The major causes of AKI were capillary leak syndrome in Period 0, ganciclovir or sulfamethoxazole/trimethoprim in Period 1, high-dose melphalan in Period 2, and engraftment syndrome in Period 3. AKI in different periods had distinct risk factors and predictive models. AKI was a risk factor for both kidney survival and overall survival (OS). Even recovered AKI reduced 10-year kidney survival from 91.7% to 68.4% (p = 0.002) and 10-year OS from 91.1% to 77.7% (p = 0.005).

Immunoglobulin light chain amyloidosis: 2024 update on diagnosis, prognosis, and treatment

DISEASE OVERVIEW

Immunoglobulin light chain amyloidosis is a clonal, nonproliferative plasma cell disorder in which fragments of immunoglobulin light or heavy chain are deposited in tissues. Clinical features depend on organs involved but can include heart failure with preserved ejection fraction, nephrotic syndrome, hepatic dysfunction, peripheral/autonomic neuropathy, and "atypical smoldering multiple myeloma or MGUS."

DIAGNOSIS

Tissue biopsy stained with Congo red demonstrating amyloid deposits with apple-green birefringence is required for the diagnosis of AL amyloidosis. Organ biopsy is not required in 85% of patients. Verification that amyloid is composed of immunoglobulin light chains is mandatory. The gold standard is laser capture mass spectroscopy.

PROGNOSIS

N-terminal pro-brain natriuretic peptide (NT-proBNP or BNP), serum troponin T(or I), and difference between involved and uninvolved immunoglobulin free light chain values are used to classify patients into four stages; 5-year survivals are 82%, 62%, 34%, and 20%, respectively.

THERAPY

All patients with a systemic amyloid syndrome require therapy to prevent deposition of amyloid in other organs and prevent progressive organ failure. Current first-line therapy with the best outcome is daratumumab, bortezomib, cyclophosphamide, and dexamethasone. The goal of therapy is a ≥VGPR. In patients failing to achieve this depth of response options for consolidation include pomalidomide, stem cell transplantation, venetoclax, and bendamustine.

FUTURE CHALLENGES

Delayed diagnosis remains a major obstacle to initiating effective therapy prior to the development of end-stage organ failure. Trials of antibodies to deplete deposited fibrils are underway.