Urinary protein selectivity in nephrotic syndrome and pregnancy: resurrection of a biomarker when renal biopsy is contraindicated

Remission induced by renal protective therapy in nephrotic syndrome with thin basement membrane in an older patient: a case report

BACKGROUND

Adult nephrotic syndrome is a well-known kidney disease that causes heavy proteinuria, hypoalbuminemia, hypercholesterolemia, edema, and hypertension. The treatment varies according to its underlying cause but often faces medication resistance or adverse drug effects.

CASE PRESENTATION

A Japanese woman in her 80s presented with nephrotic syndrome after a 3 year latent period of urinary protein and occult blood. She did not have any secondary causes of nephrotic syndrome. Renal biopsy revealed thin glomerular basement membrane, partial foot process fusion on electron microscopy with minor glomerular change on light microscopy, and slight coarse immunoglobulin M deposition in the mesangium on immunofluorescence microscopy, which was inconsistent with any other glomerular diseases. Without steroid treatment, she dramatically remitted from proteinuria after the administration of the renal protective agents enalapril, ezetimibe, rosuvastatin, and dapagliflozin. Recurrence after 8 months of follow-up subsided with the administration of additional doses of the agents.

CONCLUSIONS

This case illustrated the novel outcomes of combining medical treatment without steroid use for nephrotic syndrome with thin glomerular basement membrane disease. At the time of writing this report, the patient's renal function was stable and she was free of edema, although moderate proteinuria and occult hematuria persisted. The final diagnosis was uncertain because of the lack of genetic investigation; however, the response to the aforementioned medical treatment suggests the effectiveness of the supportive therapy.

Lactobacillus plantarum CQPC02 intervenes in mouse lupus nephritis by regulating the NF-κB signaling pathway

A strain of Lactobacillus plantarum CQPC02 (LP-CQPC02) isolated from naturally fermented kimchi was utilized in this investigation. In order to construct an animal model of lupus nephritis, pristane was used. We then used a kit to identify markers in mouse blood and tissues and a quantitative polymerase chain reaction (qPCR) to measure the expression of genes associated to nuclear factor kappa-B (NF-κB) in mouse kidney tissue. According to the results of the experiments, oral administration of LP-CQPC02 LP-CQPC02 may lessen the lupus nephritis-related rise in urine protein as well as the cytokine levels that were rising in the serum and renal tissues, including IL-6, IL-12, tumor necrosis factor alpha, and interferon. Additionally, in mice with nephritis, LP-CQPC02 can lower serum creatinine (SCr), blood urea nitrogen (BUN), total cholesterol (TC), triglyceride (TG), and raise total protein (TP) and albumin (ALB) levels. In mice with nephritis, LP-CQPC02 can also reduce the positive rate of double-stranded deoxyribonucleic acid (dsDNA). Pathological sections were examined, and it was shown that LP-CQPC02 can lessen tissue damage such incomplete glomerular morphology and inflammatory infiltration brought on by nephritis. In the kidneys of mice with lupus nephritis, LP-CQPC02 can upregulate the expression of inhibitor of NF-κB (IκB-α), downregulate the expression of NF-κB, transforming growth factor-β1 (TGF-β1), vascular endothelial growth factor (VEGF), intercellular cell adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1). Lactobacillus plantarum CQPC02 has been confirmed to have an intervention effect on nephritis in mice and has the potential as a probiotic.

Clinical features and prognosis of pregnancy-related renal damage and pregnancy after chronic kidney disease

OBJECTIVE

To explore the clinical features of renal damage related to pregnancy and pregnancy after chronic kidney disease (CKD), providing clinical evidence for the relationship between renal damage and pregnancy.

METHODS

A retrospective analysis was performed on patients admitted to our hospital between March 2013 and February 2021 who had both pregnancy and kidney damage. The study collected pathology results from renal biopsies, 24-hour urinary protein quantity, albumin (Alb), serum creatinine (Scr), blood lipids, coagulation function, blood routine, and other indicators during and after pregnancy.

RESULTS

This study included 82 cases, with 48 cases in the pregnancy-related renal damage group. Thirty-four cases were in the post-CKD pregnancy group. Of the patients, 30 cases (88.24%) had CKD stage 1-2. Results showed better pregnancy and fetal outcomes in the post-CKD pregnancy group compared to the pregnancy-related renal damage group (Ρ was 0.029 and 0.036, respectively). Renal biopsy pathology revealed that 16 cases (33.33%) in the pregnancy-related renal damage group mainly had focal segmental glomerulosclerosis (FSGS), while the post-CKD pregnancy group was dominated by 14 cases (43.75%) of IgA nephropathy. The first blood test indicators revealed that the pregnancy-related renal damage group had lower estimated glomerular filtration (eGFR) and Alb levels compared to the post-CKD pregnancy group (Ρ was 0.003 and 0.000, respectively). Additionally, 24-hour urinary protein quantity, total cholesterol (Tch), triglyceride (TG), and platelet (PLT) counts were higher in the pregnancy-related renal damage group compared to the post-CKD pregnancy group (Ρ was 0.005, 0.001, 0.008, and 0.031, respectively). The abnormal rate of Scr during pregnancy was 41.67% (20/48) in the pregnancy-related renal damage group and 17.39% (4/23) in the post-CKD pregnancy group, with a statistically significant difference (Ρ was 0.043).

CONCLUSION

The pregnancy-related renal damage group is mainly associated with FSGS, while the post-CKD pregnancy group is characterized by IgA nephropathy. Patients with CKD1-2 can have a successful pregnancy after achieving good control of eGFR, albumin, 24-hour urinary protein quantity and other indicators, resulting in better pregnancy and fetal outcomes. Abnormal Scr levels during pregnancy of pregnancy-related renal damage can be improved within 3 months after delivery.

Effects of Lactobacillus plantarum HFY15 on Lupus Nephritis in Mice by Regulation of the TGF-β1 Signaling Pathway

Objective

In this study, the Lactobacillus plantarum HFY15 (LP-HFY15) strain isolated from naturally fermented yak yogurt was investigated. An animal model of lupus nephritis was established by pristane to verify the interventional effect of LP-HFY15 on mouse lupus nephritis by regulating the transforming growth factor-β1 (TGF-β1) signaling pathway.

Materials and Methods

Indexes in mouse serum and tissues were detected by kits, pathological changes in mouse kidney were observed by hematoxylin-eosin (H&E) staining, and quantitative polymerase chain reaction (qPCR) was used to detect TGF-β 1-related expression in mouse kidney tissue, which further elucidated the mechanism of LP-HFY15.

Results

LP-HFY15 decreased the elevation of urinary protein and the levels of interleukin-6 (IL-6), IL-12, tumor necrosis factor alpha (TNF-α), and interferon γ (IFN-γ) in serum and kidney tissue. LP-HFY15 also reduced serum creatinine (SCr), blood urea nitrogen (BUN), total cholesterol (TC), triglyceride (TG), and raised total protein (TP), and albumin (ALB) levels in mice with nephritis. In addition, LP-HFY15 inhibited the positive rate of double-stranded deoxyribonucleic acid (dsDNA) antibodies in mice with nephritis. The observation of H&E sections showed that LP-HFY15 alleviated the glomerulus morphological incompleteness and inflammatory infiltration caused by nephritis. Further results showed that LP-HFY15 downregulated the mRNA expression of TGF-β1, vascular endothelial growth factor (VEGF), and nuclear factor kappa-B (NF-κB) in the kidneys of lupus nephritis mice, and the expression of inhibitor of NF-κB (IκB-α), copper/zinc superoxide dismutase (Cu/Zn-SOD), and manganese superoxide dismutase (Mn-SOD) was also upregulated.

Conclusion

These results indicated that LP-HFY15 plays a significant role in experimental intervention for lupus nephritis. The effect of LP-HFY15 was positively correlated with its concentration, and the effect was similar to that of prednisone at 10⁹ CFU/kg.

Replacing centrifugation with mixing in urine analysis enriches protein pool in the urine samples

Urine is the basic diagnostic material, easy to collect, not requiring invasive approach. During standard procedure the urine samples are centrifuged and the supernatant analysed physically, biochemically, and microscopically. The centrifugation step removes proteins including those forming aggregates especially in the state of illness and after transplantation. Here, we analysed the effect of urine centrifuging on specific protein content in urine samples obtained from cardiovascular patients (CVD) and after kidney or liver transplantation. We tested homogeneous whole urine samples, standardly centrifuge one, and the pellet after centrifuging. Protein content was examined using Western blot analysis and mass spectrometry (MS) of samples from CVD patients or the one after transplantation. The average of 21% proteins from non-centrifuged samples were found in the pellet removed after standard centrifugation. MS analysis confirmed that diagnostically important proteins were located there in. In 90% of cases whole urine samples contained more proteins than standard supernatant, among them e.g. proteins involved in immunological response like immunoglobulins and complement compounds secreted by leucocytes. Replacing centrifuging with intensive mixing of urine samples provides a method of enriching the samples with proteins removed during standard procedure, thus increasing possibility of finding new biomarkers for diseases undiagnosable with classic urine analysis.

A case of minimal change nephrotic syndrome with pregnancy

A 32-year-old Japanese woman at 8 weeks of gestation was admitted to our hospital for systemic edema, hypoalbuminemia, and severe proteinuria. The patient had a history of generalized alopecia and migraine. We diagnosed nephrotic syndrome, and renal biopsy revealed minimal change nephrotic syndrome (MCNS). We administered 1000 mg/day of methylprednisolone for 3 days. Oral corticosteroid therapy was followed by 40 mg of prednisolone daily. We carefully selected concomitant medication after considering organogenesis. Before and after renal biopsy, we administered heparin, antithrombin III, and immunoglobulin agents as appropriate. The patient achieved complete remission on day 8 of treatment and gave birth to a boy at 37 weeks of gestation without recurrence. MCNS during pregnancy is rare, and there is no established treatment. In conclusion, we present a case of a pregnant woman with MCNS during organogenesis. Early treatment initiation can provide a good prognosis for both mother and child.

Steroid Pulse Therapy for De Novo Minimal Change Disease During Pregnancy

BACKGROUND Nephrotic syndrome occurs very rarely, in only about 0.01%-0.02% of all pregnancies, and de novo minimal change disease during pregnancy is especially rare. Nephrotic syndrome and, especially, minimal change disease are highly responsive to steroids, and preterm labor may be avoidable if the maternal condition is improved with steroid therapy. Therefore, prompt diagnosis and proper management are critical to maternal and fetal outcome when severe proteinuria occurs during pregnancy. CASE REPORT A 30-year-old pregnant Japanese woman presented with systemic edema, oliguria, and severe proteinuria and hypoalbuminemia at 25 weeks of gestation, although she was normotensive. The patient had high urinary protein selectivity. Her illness was diagnosed as de novo nephrotic syndrome with high steroid responsiveness rather than pre-eclampsia. She began steroid pulse therapy the day after admission. Complete remission was confirmed after 3 weeks. The patient did not relapse during pregnancy and delivered a healthy male baby at 37 weeks of gestation. A renal biopsy at a relapse after delivery confirmed minimal change disease. CONCLUSIONS In pregnant women with de novo minimal change disease, serious maternal and/or fetal complications may occur if severe proteinuria and hypoalbuminemia are unabated for an extended time. Evaluation of urinary protein selectivity is noninvasive and useful for prediction of steroid responsiveness. Results of urinary protein selectivity can be obtained earlier than results of renal biopsy. Renal biopsy during pregnancy is not always necessary for initiation of steroid therapy. Rapid initiation of steroid pulse therapy may enable quicker achievement of remission and prevent serious perinatal complications.

Nephrotic syndrome in pregnancy poses risks with both maternal and fetal complications

In the absence of uncontrolled hypertension or renal insufficiency, many consider the perinatal outcomes in pregnant women with nephrotic syndrome to be good. To further investigate this we performed a retrospective chart review of women with biopsy-proven nephrotic syndrome due to primary glomerular disease during pregnancy at a single tertiary center. Our review determined characteristics, presentation, management, pathologic diagnoses, and associated renal and maternal-fetal outcomes of 19 individuals with 26 pregnancies and 26 offspring. The mean age was 27.6 years, the mean gestational age at the presentation of nephrotic syndrome was 18.6 weeks, the mean creatinine was 0.85 mg/dL, mean serum albumin was 1.98 g/dL, and the mean proteinuria was 8.33 g/24 hours. The mean cardiac output was 8.6 L/minute, which was elevated compared to normal pregnancy. A kidney biopsy was performed during pregnancy in 8 individuals (median gestational age at time of biopsy was 21 weeks), changing management in six. Of the 26 pregnancies, maternal complications included preeclampsia in seven, acute kidney injury in six, premature rupture of membranes in two, and cellulitis in three. The mean age of gestation at delivery was 35.5 weeks. Fetal complications included low birth weight (under 2,500 g) in 14, intra-uterine growth restriction in three, and neonatal intensive care unit admission in eight. Thus, pregnant women with nephrotic syndrome are at high risk for developing both maternal and fetal complications, even in the absence of significant renal impairment or uncontrolled hypertension at the time of presentation of nephrotic syndrome.

A Unique Cause of Proteinuria in Pregnancy: Class II Lupus Nephritis with Concomitant Minimal Change Disease

We report the case of a 22-year-old African American female who presented to another facility for routine follow-up in the 34th week of pregnancy with lower extremity swelling and nephrotic-range proteinuria. Although she was normotensive, it was initially thought that she had preeclampsia. She was monitored carefully and delivery was induced at 37 weeks of gestation. She was transferred to our hospital, where she was diagnosed with systemic lupus erythematosus (SLE) based on clinical and laboratory criteria. Renal biopsy revealed a surprising finding of minimal change disease (MCD) concomitant with class II lupus nephritis (LN). She was managed with pulses and then tapering doses of steroid therapy with dramatic resolution of the nephrotic syndrome. This case demonstrates not only the rare de novo occurrence of SLE in pregnancy, but the unique finding of MCD coexisting with class II LN. We propose that altered T cell activity may be the link between these seemingly distinct entities.