The goal of this real-world observational study is to evaluate the effectiveness and safety of the Chinese herbal-derived therapeutic Danshen injection following immunosuppressive therapy and prophylactic anticoagulation with low molecular heparin for acute kidney injury in primary nephrotic syndrome. The main questions to answer are:

Whether or not Danshen injection is beneficial for acute kidney injury patients in primary nephrotic syndrome patients.

Whether or not Danshen injection will increase the bleeding risk in primary nephrotic syndrome patients receiving low molecular heparin.

Participants' information will be retrieved from hospital files stored in medical records and the electronic patient data registry. Participants received Danshen injection will be compared with control group to evaluate the recovery of renal function and side effects.

Background and objectives： Acute kidney injury (AKI) is a common complication of primary nephrotic syndrome (PNS), affecting approximately 23.7% to 34% of PNS patients. No randomized clinical trials and clinical drug intervention studies focus on renal function recovery of AKI in PNS patients. The aim of this study is to assess the clinical effectiveness and safety of a common traditional Chinese herbal medicine (Danshen) in PNS with AKI patients.

Methods:

This study will be a retrospective cohort study of PNS with AKI patients. Renal function recovery and adverse events of the patients receiving Danshen injection(DS group) will be compared with that of the patients with supportive care(SC group) .The study will be conducted using Hospital Information System of the First Affiliated Hospital of Wenzhou Medical University which has longitudinal health information on over 6 million predominantly privately insured individuals and includes over 50 million followup records. The data of inpatients diagnosed with nephrotic syndrome will be reviewed retrospectively. Patients' information includes socio-demographic characteristics, administrative claims (diagnosis and procedure codes), medical histories, laboratory test results and pharmacy claims. PNS wih AKI inpatients will be enrolled. The baseline characteristics will be propensity-score matched. The outcomes are complete and partial renal function recovery for effectiveness analysis and severe bleeding events for safety analysis. Comparisons of cumulative recovery rate will be performed by Kaplan-Meier curves and log-rank test. Risks for outcomes will be assessed using Cox proportional hazard regression models.

Inclusion Criteria:

1. age >=20yr;
2. Patients must have at least one "Evaluation and Management"visit with a diagnosis of PNS 6 months before index date;
3. Patients must have AKI at the index date.

Exclusion Criteria:

1. Secondary necrotic syndrome, which is define as necrotic syndrome caused by diabetic nephropathy, lupus nephritis, castleman syndrome, cryoglobulinemia, lymphoma, systemic vasculitis, hepatitis C associated nephritis, hepatitis B associated nephritis, monoclonal immunoglobulinemia, amyloidosis, Sjogren's disease, myeloma, macroglobulinemia and Henoch-Schonlein purpura nephritis；
2. Cancer patients；
3. Liver cirrhosis；
4. Transplant patients;
5. Guillain-Barre syndrome；
6. Maintain Remission in PNS；
7. Chronic renal failure；
8. PNS without AKI;
9. PNS with autosomal dominant polycystic kidney disease;
10. AKI caused by bleeding, haemolytic uraemic syndrome, malignant hypertension，IgG4 related tubulointerstitial nephritis, infection, acute coronary syndrome or heart failure, obstructive nephropathy and nephrotoxic drug ;
11. PNS accompanied with pulmonary embolism, acute cerebrovascular accident,Pregnancy;
12. Acute rapid progressive or Crescentic Glomerulonephritis;
13. Patients without valid data .

The study will be conducted using Hospital Information System of the First Affiliated Hospital of Wenzhou Medical University which has longitudinal health information on over 6 million predominantly privately insured individuals and includes over 50 million followup records. 3873 patients with nephrotic syndrome will be reviewed retrospectively. Patients' information includes socio-demographic characteristics, administrative claims (diagnosis and procedure codes), medical histories, laboratory test results and pharmacy claims.