Successful Maintenance Therapy with Intravenous Immunoglobulin to Reduce Relapse Attacks and Steroid Dose in a Patient with Refractory Myelin Oligodendrocyte Glycoprotein Antibody-positive Optic Neuritis.

A 25-year-old Japanese man developed visual disturbance with eye pain and was diagnosed with optic neuritis associated with anti-myelin oligodendrocyte glycoprotein antibodies. His symptoms improved temporarily after steroid therapy but chronically relapsed many times after tapering the steroid dose. He became highly steroid-dependent and was referred to our department for reconsideration of the treatment strategy. Maintenance intravenous immunoglobulin (IVIg) therapy successfully decreased the annual recurrence rate from 1.15 to 0.27 times/year and the maintenance dose of oral prednisolone from 35 to 5 mg/day. Maintenance IVIg therapy is a promising option for preventing disease relapse in such cases.

Coexistence of variant-type transthyretin and immunoglobulin light-chain amyloidosis: a case report.

Background: Determining the type of amyloid deposits is clinically important for choosing the specific therapies for cardiac amyloidosis. Case summary: A 78-year-old woman who had been experiencing fluid retention and dyspnoea on exertion for 6 months was referred to our hospital for the management of heart failure with left ventricular hypertrophy. Since 99mTc-hydroxymethylene diphosphonate scintigraphy showed mild cardiac uptake and significant elevation of serum free lambda chain (with a difference of 263 mg/L in free light chain), we suspected immunoglobulin light-chain amyloidosis (AL), and endomyocardial biopsy was performed. The deposit site within the myocardial tissue exhibited positive for Congo red staining and transthyretin immunostaining, however negative or non-specific for light-chain immunostaining including lambda and kappa staining. Genetic testing confirmed a mutation in V122I, variant-type transthyretin amyloidosis (ATTRv). Despite the administration of patisiran, her condition exhibited progressive deterioration. Additionally, she displayed macroglossia, an atypical manifestation in ATTRv amyloidosis. Further biopsies from tongue and abdominal wall fat culminated in a final diagnosis: the coexistence of ATTRv and AL (of the lambda type). Although treatment with melphalan and dexamethasone was started, she passed away 24 months after the initial visit. When the endomyocardial biopsy specimen underwent mass spectrometry as a post hoc analysis, both ATTR and AL amyloid were significantly detected. Discussion: Coexistence of ATTRv and AL within cardiac amyloidosis is extremely uncommon. In situations where incongruities arise between the amyloid type determined via immunohistochemistry findings and the amyloid type assumed based on other clinical findings, mass spectrometry should be considered.

Amyloid-Forming Corpora Amylacea and Spheroid-Type Amyloid Deposition: Comprehensive Analysis Using Immunohistochemistry, Proteomics, and a Literature Review.

This study aimed to elucidate the similarities and differences between amyloid-forming corpora amylacea (CA) in the prostate and lung, examine the nature of CAs in cystic tumors of the atrioventricular node (CTAVN), and clarify the distinctions between amyloid-forming CA and spheroid-type amyloid deposition. We conducted proteomics analyses using liquid chromatography-tandem mass spectrometry with laser microdissection and immunohistochemistry to validate the characteristics of CAs in the lung and prostate. Our findings revealed that the CAs in these organs primarily consisted of common proteins (ß2-microglobulin and lysozyme) and locally produced proteins. Moreover, we observed a discrepancy between the histopathological and proteomic analysis results in CTAVN-associated CAs. In addition, while the histopathological appearance of the amyloid-forming CAs and spheroid-type amyloid deposits were nearly identical, the latter deposition lacked ß2-microglobulin and lysozyme and exhibited evident destruction of the surrounding tissue. A literature review further supported these findings. These results suggest that amyloid-forming CAs in the lung and prostate are formed through a shared mechanism, serving as waste containers (wasteosomes) and/or storage for excess proteins (functional amyloids). In contrast, we hypothesize that while amyloid-forming CA and spheroid-type amyloid deposits are formed, in part, through common mechanisms, the latter are pathological.

Enterocolic granulomatous phlebitis associated with epidermal growth factor-containing fibulin-like extracellular matrix protein 1 deposition and focal amyloid properties: A case report.

A woman in her 60s with rheumatoid arthritis was admitted with fever and abdominal pain. Laparoscopic examination with the differential diagnosis of peritoneal neoplasm and infection revealed granulomatous phlebitis in the resected greater omentum. Amorphous eosinophilic deposits observed in the resected tissue exhibited focal, weak positivity for Congo red but were strongly positive for thioflavin S, confirming their focal amyloid properties. Marked degeneration of elastic fibers was also evident. Electron microscopy revealed deposits around the affected elastic fibers. Immunohistochemistry revealed the deposition of epidermal growth factor-containing fibulin-like extracellular matrix protein 1 (EFEMP1) along with T-cell-predominant lymphocytic inflammation. The definitive diagnosis was granulomatous enterocolic lymphocytic phlebitis (ELP) associated with EFEMP1 deposition exhibiting focal amyloid properties (EFEMP1/AEFEMP1), supported by proteomics analysis. This type of vasculitis is similar to amyloid-ß-related angiitis of the central nervous system. Thus, we speculate that granulomatous ELP also results from an immune response that recognizes EFEMP1/AEFEMP1 deposits as foreign material and attempts to remove them. Confirmation of EFEMP1/AEFEMP1 deposition with Congo red staining is challenging, particularly in the presence of inflammation, and warrants comprehensive evaluation.