On December 15, 2020, the patient underwent physical examination, and the report showed positive urine protein (++), blood routine: white blood cell count, 16.531 × 109/L; hemoglobin level, 229 g/L; red blood cell > 7.8 × 1012/L; and platelet count, 489 × 109/L. Biochemistry test: albumin 37 g/L, total albumin 60 g/L, blood uric acid 490 µmol/L, triglyceride 3.87 mmol/L, and blood creatinine 88 µmol/L.
On December 31, 2020, the 24-hour urine total protein quantitative was 5.08 g/24 h.
On January 7, 2021, routine blood tests showed white blood cells: 21.71 × 109/L; platelets, 431 × 109/L; red blood cells, 7.65 × 1012/L; and hemoglobin, 216.7 g/L.
On January 11 and 15, the patient underwent bone marrow and renal biopsies, respectively, after providing informed consent. A bone marrow biopsy revealed dense bone and a small amount of bone marrow tissue. The ratio of hematopoietic cells to structural fat in the area available for observation was 85%:15%, and the grain-to-red ratio was approximately 4–5:1. Hematopoietic cells in all stages of the red line could be seen; megakaryocytes were 7–17 per high-power field, distributed in clusters, and the cell bodies were relatively large with more nuclear lobes.
On January 11, 2021, a bone marrow biopsy showed that PV was first considered, and further genetic examination was recommended to clarify the type. IHC2021-0042: CD34 (individual +), CD117 (individual +), CD15 (partial +), MPO (partial +), CD56 (-), CD138 (individual +), CD61 (discrete +), CD71 (part +), Kappa: Lambda (not restricted expression), and special stain results: mesh (-), Periodic Acid-Schiff stain (+/-), Prussian blue (-).
On January 13, 2021, karyotype analysis showed the following karyotype: 46,XY (Figure 1). Gene test: JAK2 V617F (+). The mutation ratio of JAK2 V617F was 86.60%.
Figure 1 Karyotype analysis results.
On January 15, 2021, renal biopsy (renal puncture tissue) revealed four glomeruli. The morphology and structure of glomeruli were normal. Some glomeruli showed mild proliferation of mesangial cells and increased matrix. No glomerular sclerosis changes, crescents, or infiltration of inflammatory cells were observed. Protein casts were observed in individual tubules, and some renal tubules showed atrophy and unclear structure. No obvious abnormalities were observed in the renal interstitium or blood vessels. Diagnosis: Minimal change disease (MCD). Fluorescence staining: IgG (-), IgA (-), IgM (-), C3 (-), C4 (-), C1q (-), Fb (+/-). Special staining: PAS (+), silver staining (+), Masson’s trichrome (+), Congo red (-). IHC2021-0045: TGF B1 (-) (Figure 2).
Figure 2 Renal biopsy results.