07 June 2022
: Case report 
Thrombotic Microangiopathy Secondary to Systemic Sclerosis with Severe Complement Activation Not Responsive to Eculizumab: A Case Report
Unusual clinical course, Challenging differential diagnosis, Unusual or unexpected effect of treatment, Diagnostic / therapeutic accidents, Unexpected drug reaction
Masahiko Nakamura1ABCDEF*, Tomohiro Abe
1ABCDE, Hidenobu Ochiai1ACDE
DOI: 10.12659/AJCR.936116
Am J Case Rep 2022; 23:e936116
Table 2. Laboratory values at the diagnosis of systematic sclerosis-thrombotic microangiopathy.
| Normal range | ||
|---|---|---|
| Haptoglobin (mg/L) | 1100 | 300–2000 |
| Direct Coombs test | Negative | Negative |
| Indirect Coombs test | Negative | Negative |
| ADAMTS13 activity (%) | 14.8 | >70 |
| ADAMTS13 inhibitor (BU) | <0.4 | <0.4 |
| Anti-LPS-IgM Antibody | Negative | Negative |
| Anti-nuclear Antibody | 1: 20480 | 1: 40 |
| Anti-CL-IgG Antibody (U/mL) | 8 | <10 |
| Anti-ds-DNA Antibody (U/mL) | 10 | <30 |
| Anti-RNP Antibody (U) | <1.0 | <1.0 |
| Anti-scl-70 Antibody (U) | <1.0 | <1.0 |
| Anti-SS-A Antibody (U) | <1.0 | <1.0 |
| Anti-SS-B Antibody(U) | <1.0 | <1.0 |
| Anti-RNA polymerase III Antibody | 13 | <28 |
| PR3-ANCA (U) | <1.0 | <1.0 |
| MPO-ANCA (U) | <1.0 | <1.0 |
| Plasma renin activity(ng/ml/h) | 0.7 | 0.2–2.3 |
| Complement component 3 (g/L) | 0.59 | 0.73–1.38 |
| Complement component 4 (g/L) | 0.12 | 0.11–0.31 |
| 50% homolytic complement activity (U/ml) | 19 | 25.0–48.0 |
| Soluble complement 5b-9 (ng/mL) | 11041 | <250 |
| Anti-NOR90/hUBF Antibody | Positive | Negative |
| Anti-fibrillarin Antibody | Positive | Negative |
| ADAMTS13 – a disintegrin-like and metalloproteinase with thrombospondin type 1 motifs 13; LPS – lipopolysaccharide; IgM – immunoglobulin M; CL – cardiolipin; IgG – immunoglobulin G; Anti-CL β2GP – anti-cardiolipin antibody/β2-glycoprotein; ds-DNA – double-stranded deoxyribonucleic acid; RNP – ribonucleoprotein; scl-70 – topoisomerase-1; anti-SS-A, anti-Ro; anti-SS-B, anti-La; NOR90/hUBF – nucleolar organizing region 90/human upstream-binding factor; PR3-ANCA – anti-proteinase 3-antineutrophil cytoplasmic autoantibodies; MPO-ANCA – myeloperoxidase- antineutrophil cytoplasmic autoantibodies. | ||