Analysis of the causes of misdiagnosis of multiple myeloma as acute pancreatitis and nephrotic syndrome

XIE Jia; XIANG Mei; YANG Jiwen

doi:10.3969/j.issn.1002-3429.2025.23.004

Abstract：Objective To analyze the causes of misdiagnosis of multiple myeloma as acute pancreatitis or nephrotic syndrome and methods to correct misdiagnosis,in order to improve the clinical diagnosis and treatment capabilities of physicians.Methods The clinical data of one patient with initial diagnosis of acute pancreatitis and one patient with initial diagnosis of nephrotic syndrome admitted from January 2023 to January 2024 were retrospectively reviewed.Results One patient was hospitalized for abdominal pain for 3 d and anuria for 1 d.Physical examination showed tenderness around the umbilicus.Laboratory examination showed anemia,renal function damage,and slight increase of amylase,which were misdiagnosed as acute pancreatitis,and there was no improvement after symptomatic treatment.CT examination revealed no findings indicative of pancreatitis.The serum light chain was significantly abnormal,abnormal plasma cells were found in bone marrow aspiration,and multiple myeloma[Immunoglobulin G-κtype,Durie-Salmon stage Ⅲ(DS Ⅲ)]was diagnosed by immunofixation electrophoresis.The misdiagnosis lasted 6 d.During symptomatic treatment,the patient suddenly developed ST-T changes and elevated troponin levels,and died at 13 d after admission;autopsy confirmed light chain myocardial deposition.Autopsy diagnosis was cardiac amyloidosis of light-chain type secondary to multiple myeloma.One patient was hospitalized due to edema of both lower limbs for over two months.Laboratory examination showed massive proteinuria and hypoalbuminemia,which was consistent with nephrotic syndrome.Further examination showed serum M protein(Immunoglobulin A-λ type),bone marrow aspiration showed abnormal plasma cells,fluorescence in situ hybridization was positive for 1q21 and 13q14,and amyloidosis was confirmed by renal biopsy.The patient was diagnosed as multiple myeloma(Immunoglobulin A-λ type)with renal amyloidosis.The misdiagnosis lasted 7 d.After 6 courses of BCD chemotherapy,the levels of serum M protein and 24-hour urinary M protein were significantly improved,and no new osteolytic lesions or plasmacytoma were found by imaging examination.The patients were followed up for 6 months,with stable condition.Conclusion Multiple myeloma,due to its complex and varied symptoms,is easily confused with diseases such as acute pancreatitis and nephrotic syndrome.It is crucial to be vigilant and comprehensively use multiple diagnostic modalities to reduce misdiagnosis.