Table 1.

Patient demographics and clinical characteristics

	Patient 1	Patient 2	Reference range
Clinical presentation
Age, yr/race/sex	41/Chinese/female	60/Malay/female
Medical history	Gestational diabetes mellitus	Hyperlipidemia
Date of vaccination
First dose	March 3, 2021	January 29, 2021
Second dose	March 26, 2021	February 19, 2021
Date of hematuria	March 27, 2021	February 20, 2021
Date of presentation to nephrology	March 28, 2021	March 31, 2021
Blood pressure at presentation, mm Hg	153/99	188/95
Significant laboratory results^a
Serum creatinine, μmol/L	153	541
Urine dysmorphic red blood cells/μl	>200	>200
Urine protein-to-creatinine ratio, g/g	2.03	7.58
Serum Ig
Serum IgG, g/L	12.90	9.95	5.49–17.11
Serum IgA, g/L	6.40	1.62	0.47–3.59
Serum IgM, g/L	1.10	0.35	0.15–2.59
Complement C3, g/L	0.83	1.11	0.90–1.80
Complement C4, g/L	0.20	0.24	0.10–0.40
Anti-nuclear antibody	1:320; Homogeneous	Negative
Anti-GBM antibody (ELISA)	<1.5	10.0	<7 U/ml = negative; 7–10 U/ml = indeterminate; >10 U/ml = positive
Anti-GBM antibody (IF)	Not done	Positive
Histopathology report
Glomeruli	36 Glomeruli; 5 globally sclerosed. Focal proliferative glomerulonephritis with focal segment glomerulosclerosis; 6% cellular and 8% fibrocellular crescents	22 Glomeruli; 6 segmentally sclerosed. Diffuse crescentic glomerulonephritis with segmental sclerosis; 59% cellular, 14% fibrocellular, and 5% fibrous crescents
Tubules and interstitium	Mild tubulointerstitial inflammation. Mild tubular atrophy and interstitial fibrosis	Acute tubular injury Mild tubular atrophy
Vessels	Mild hyalinosis. No vasculitis or thrombotic microangiopathy	Mild intimal fibrosis
IF	Dominant glomerular IgA staining	Trace to 1+ linear IgG staining of glomerular basement membrane
Electron microscopy	Electron-dense deposits mostly in mesangial and paramesangial locations	No electron-dense deposits
Treatment	Pulse methylprednisolone, followed by oral prednisolone; i.v. cyclophosphamide	Pulse methylprednisolone, followed by oral prednisolone; oral cyclophosphamide; plasma exchange

ELISA, enzyme-linked immunosorbent assay; GBM, glomerular basement membrane; IF, immunofluorescence.

Other autoantibodies, such as anti–streptomycin O titer (ASOT), anti–double-stranded DNA (anti-dsDNA), anti–neutrophil cytoplasmic antibody (ANCA) by IF, anti-myeloperoxidase, and anti–proteinase 3 antibodies, were not detected.