PMC9376367_01
Clinical course. The upper graph shows the activity of TTP, and the lower graph shows the disease activity of SLE and lupus nephritis, both in (A,B). (A) Clinical course for the first 31 days after admission is shown. Three courses of plasma exchange (PE) were effective to remove anti-ADMTS13 antibody (ADMTS13inh) and to increase a platelet count (Plt) rapidly. However, 30 mg of prednisolone (PSL) injection and fresh-frozen plasma (FFP) infusion were not sufficient to suppress antibody production to recover ADAMTS13 activity (ADAMTS13act) and to maintain the platelet count. After two courses of methylprednisolone pulse therapy (MPT), the recovery of the ADAMTS13 activity and the platelet count was observed. Proteinuria disappeared after the first course of pulse therapy. Renal biopsy was performed on the 25th hospital day. (B) Overall clinical course is shown. Treatment details and clinical data are shown following (A). Since the patient was considered to be in the high-risk group of SLE organ damage, and TMA is known to have frequent complications of psychiatric symptoms, she was additionally treated with three courses of intravenous cyclophosphamide pulse therapy (IVCY) as induction therapy for SLE, in addition to mycophenolate mofetil (MMF) and hydroxychloroquine (HCQ). HCQ was discontinued because color blindness and retinopathy were suspected at a regular ophthalmologic visit, and belimumab (BLM) was started instead just after BLM had become under health insurance coverage for SLE pediatric patients (B). Ur Pro/Cre, urinary protein creatinin ratio; anti ds-DNA IgG, anti-double-stranded DNA immunogloburin G; ESR, erythrocyte sedimentation rate.
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The clinical course is shown in Figure 1. ADAMTS13 activity increased, and the platelet count rapidly increased (Figure 1A). Additionally, urinary findings were normal after the first course of pulse therapy. SLE. Since she was considered to be in the high-risk group of SLE organ damage, and TMA is known to have frequent complications of psychiatric symptoms, she was additionally treated with three courses of intravenous cyclophosphamide pulse therapy [IVCY, 580 mg/dose (500 mg/m2)] as induction therapy for SLE (Figure 1B). After 1 year and 4 months since the onset, belimumab (BLM) was administered instead just after BLM had become under health insurance coverage for SLE pediatric patients (Figure 1B).
Renal pathology. (A) Light microscopy. Periodic acid Schiff stain, original magnification 200 x. A wire loop lesion and endocapillary hypercellularity (the yellow circle), and duplication in glomerular basement membrane (the yellow arrowhead) are observed. (B) Light microscopy. Periodic acid silver-methenamin + hematoxylin-eosin staining, original magnification 200 x. Thrombus formation with luminal stenosis in afferent arteriole (the yellow arrow) and wire loop lesion (the yellow arrowhead) are observed. (C) Immunofluorescent staining. Full-house positive staining at the capillary wall and, mainly, in the paramesangial region is shown. (D) Electronic microscopy. Electron-dense deposits in the paramesangial region (the yellow circle) are observed comparable to IF findings.
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III (A) (Figure 2A). Notably, granular periodic acid-Schiff stain-positive thrombi were found in afferent arterioles, and glomeruli with luminal stenosis in afferent arterioles were observed in 6 of 26 glomeruli, which was considered to be consistent with TTP (Figure 2B). Immunofluorescent staining (IF) showed full house positive at the capillary wall and, mainly, in the paramesangial region (Figure 2C). Electron-dense deposits were observed in the paramesangial region with electron microscopy, which were comparable to IF findings (Figure 2D).