A Case Of Neuron-derived Neurotrophic Factor-positive, Syphilis-related Membranous Nephropathy That Achieved Spontaneous Remission
Yoshida, Y., Ueki, K., Matsukuma, Y., Tsuchimoto, A., Ataka, E., Okamoto, H., Torisu, K., Hara, Y., Ikeda, H., Kitazono, T., & Nakano, T. (2025). A case of neuron-derived neurotrophic factor-positive, syphilis-related membranous nephropathy that achieved spontaneous remission. CEN case reports, 14(3), 318–323. https://doi.org/10.1007/s13730-024-00960-5
View Original Source →Abstract
Neuron-derived neurotrophic factor (NDNF) was discovered as a target antigen in membranous nephropathy (MN) caused by syphilis. However, there have been few reports of NDNF-positive MN in Japan. A 19-year-old female patient was admitted to our hospital with nephrotic syndrome and acute kidney injury. After admission, she presented with a skin rash and was serologically positive for syphilis. Kidney biopsy showed MN positive not only for immunoglobulin (Ig) G, but also for IgA and complement C1q. IgG subclass analysis revealed positivity for IgG1 and IgG3. Immunohistochemistry for glomerular NDNF was positive, and a diagnosis of syphilis-related MN was confirmed. Prior to treatment of the infection, her urinary protein decreased to achieve complete remission and her kidney function improved. Benzylpenicillin was administered, and no recurrence of nephrotic syndrome or kidney dysfunction was observed thereafter. This case illustrates the importance of considering syphilis infection when encountering a case of nephrotic syndrome with skin rash. In addition, urinalysis of syphilitic patients should be performed to avoid missing MN that may be in spontaneous remission. Further elucidation of the pathogenesis of NDNF-positive, syphilis-related MN in Japan is needed.
Case Details
Disease Location
Kidney
Personal Characteristics
19-year-old female
Clinical Characteristics
Six days before, she had exhibited nausea, upper respiratory tract infection, and fever. Two days before visiting, edema appeared in her lower legs and a skin rash was observed on her arms. On physical examination, she had marked leg edema, but her skin rash had disappeared at the time of admission. Both the rapid plasma reagin test for syphilis and the treponema pallidum hemagglutination assay were positive. A kidney biopsy was performed. Immunofluorescence analysis revealed granular deposits of c3, c1q, IGG, and IGA in the wall of the glomerular loop, leading to the diagnosis of membranous nephropathy (mn) ehrenreich–churg stage i. Immunostaining for neuron-derived neurotrophic factor (ndnf9 was attempted because syphilis-related mn was strongly suspected. The results confirmed that ndnf co-localized with IGG at the glomerular loop
Remission Characteristics
On the day 10 after admission, urinary protein decreased spontaneously, and the patient was in complete remission,
Treatment & Mechanisms
Clinical Treatment
Biopsy