PMC9553724_01
PMC9553724_02
Graph showing serum levels of creatine kinase (CK) and albumin (Alb) over time after discharge from first admission to our hospital. The left vertical axis indicates the serum CK levels ((U/L), closed black circles), and the right axis indicates serum albumin (Alb) levels ((mg/dL), open circles). The horizontal line indicates the months (Mo) after discharge from first admission. *indicates the timing of discharge of first admission to our hospital. **indicates readmission to our hospital. CyA: cyclosporine A.
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fig1
The serum CK levels continued to increase over several months (Figure 1), at which point she developed hypoalbuminemia and nephrotic-range proteinuria, and was admitted to our hospital again.
Magnetic resonance imaging (MRI) of bilateral thigh muscles of a woman who developed recurrent anti-glycyl tRNA synthetase (EJ) antibody-positive dermatomyositis concurrently with newly developed nephrotic syndrome shown are sagittal (a) and axial. (b) MRI images demonstrating wide-spread high-intensity lesions on T2-weighted sequences.
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Muscle magnetic resonance imaging (MRI) revealed the presence of diffuse high signal intensity lesions in the bilateral thigh on T2-weighted and short-tau inversion recovery (STIR) sequences (Figure2).
Renal biopsy showing deposition of immunoglobulin G (IgG) and complement 3 (C3) in a woman who developed recurrent anti-glycyl tRNA synthetase (EJ) antibody-positive dermatomyositis concurrently with newly developed nephrotic syndrome. (a) Hematoxylin and eosin (HE) stain; (b) periodic acid methenamine silver (PAM) stain; immunofluorescence examination: (c) total IgG; (d) IgG1; (e) IgG2; (f) IgG3; (g) IgG4; (h) C3. Light microscopic examinations using HE and PAM stains show neither thickening nor spike formation of basement membranes. Deposition of IgG, IgG1, IgG2, IgG4, and C3 is noted. Immunoglobulin A (IgA) and immunoglobulin M (IgM) are absent (data not shown).
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To determine the underlying renal pathology of nephrotic syndrome, a renal biopsy was performed (Figure 3). However, the deposition of immunoglobulin G (IgG) (++), IgG1 (+++), IgG2 (+++), IgG3 (-), IgG4 (+++), immunoglobulin A (IgA) (-), immunoglobulin M (IgM) (+-), complement 3 (C3) (+++), complement 1q (C1q) (+-), and complement 4 (C4) (-) was observed in the glomerulus by immunofluorescence (Figure 3), which suggests the possibility of membranous nephropathy at an early stage, i.e., before the deposition of immune complexes causes apparent basement thickening.
Graph showing serum levels of creatine kinase (CK) and urine protein-to-creatinine ratio (Up/Uc ratio) over time after second admission to our hospital. The left vertical axis indicates the serum CK levels ((U/L), closed black circles), and the right axis indicates the degree of proteinuria, expressed as (Up/Uc) ratio (open circles). The horizontal line indicates the months (Mo) after discharge of first admission. Up: urinary protein; Uc: urinary creatinine. **indicates readmission to our hospital. CyA: cyclosporine A.
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This led to normalization of serum CK levels and proteinuria expressed as urine protein-to-creatinine ratio (Figure 4).