Tag Archive for: FSGS

High magnification micrograph of focal segmental glomerulosclerosis

Reducing urinary protein for patients with FSGS slows kidney decline

High magnification micrograph of focal segmental glomerulosclerosis

High magnification micrograph of focal segmental glomerulosclerosis (FSGS).

Reducing the amount of protein in the urine of patients with focal segmental glomerulosclerosis (FSGS), a rare disease in which scar tissue forms on the parts of the kidneys that filter waste from the blood, can significantly slow declines in kidney function and extend time before patients’ kidneys fail, a new analysis by a Children’s National Hospital researcher and her colleagues shows. These findings, published online Aug. 10, 2020, in the American Journal of Kidney Disease, could provide hope for patients who are able to lower their urinary protein with available treatments but aren’t able to achieve complete remission, the researchers say.

FSGS affects about seven per every million people in the general population. However, in the United States, it’s responsible for between 5 and 20% of all cases of end stage kidney disease (ESKD), a condition in which the kidney function declines enough that patients can’t survive without dialysis or a kidney transplant. There are no proven treatments specifically targeting FSGS, but steroids and other immunosuppressants have shown promise in clinical trials.

One characteristic sign of FSGS is proteinuria, in which too much protein is present in patients’ urine. Most clinical trials of FSGS treatments have focused on complete remission of proteinuria as a sign that the intervention is working. However, says Marva Moxey-Mims, M.D., researcher and chief of the Children’s National Division of Nephrology, only a fraction of patients meet that end goal. Instead, many patients achieve some reduction in proteinuria, but it’s been unclear whether those reductions lead to significant benefits for kidney health.

To investigate this question, Dr. Moxey-Mims and her colleagues used data from the National Institutes of Health-funded FSGS clinical trial that took place between November 2004 and May 2008. Participants in this study — 138 patients who developed proteinuria due to FSGS between the ages of 2 and 40 and didn’t respond to steroids — received one of two different immunosuppressant regimens. They received frequent checkups including urinary protein tests during the duration of the study and were followed for a maximum of 54 months.

Results showed that about 49% of the study participants’ proteinuria improved by 26 weeks of treatment on either regimen. More importantly, says Dr. Moxey-Mims, these patients retained significantly better kidney function over time, determined by a test called estimated glomerular filtration rate (eGFR), compared to those whose urinary protein remained high. The greater the reduction in proteinuria, the better their kidney function remained, and the longer their kidneys remained active before they developed ESKD.

“Even a modest reduction in proteinuria, as small as 20 or 30%, had an impact on these patients’ kidney health,” Dr. Moxey-Mims says.

Dr. Moxey-Mims notes that the finding could impact the design of clinical trials for FSGS treatments. Currently, these trials typically must include large numbers of patients to show a benefit if complete remission of proteinuria — which only occurred in about 20% of patients in the National Institute of Diabetes and Digestive and Kidney Diseases trial — is used as the end point.

If researchers use a range of proteinuria reduction as end points, she says, it could be easier to see if a drug or other intervention is working.

Similarly, she says, patients with FSGS and their doctors should view any proteinuria reduction as a positive.

“They shouldn’t be discouraged if they can’t reach full remission,” Dr. Moxey-Mims says. “Doctors and patients alike can feel reassured that if they’re reducing protein in the urine to some degree, then patients are getting some benefit.”

 

little girl in hosptial corridor

A growing list of factors that impact CKD severity for kids

little girl in hosptial corridor

Myriad biological and societal factors can impact the occurrence and accelerate progression of chronic kidney disease for children of African descent – including preterm birth, exposure to toxins during gestation and lower socioeconomic status – and can complicate these children’s access to effective treatments.

Myriad biological and societal factors can impact the occurrence and accelerate progression of chronic kidney disease (CKD) for children of African descent – including preterm birth, exposure to toxins during gestation and lower socioeconomic status – and can complicate these children’s access to effective treatments, according to an invited commentary published in the November 2018 edition of American Journal of Kidney Diseases.

Clinicians caring for “these vulnerable children should be mindful of these multiple competing and compounding issues as treatment options are being considered along the continuum from CKD to kidney failure to transplantation,” writes Marva Moxey-Mims, M.D., chief of the Division of Nephrology at Children’s National Health System.

The supplemental article was informed by lessons learned from The Chronic Kidney Disease in Children (CKiD) longitudinal study and conversations that occurred during the Frank M. Norfleet Forum for Advancement of Health, “African Americans and Kidney Disease in the 21st Century.”

African American children represent 23 percent of the overall population of kids with CKD in the CKiD study. While acquired kidney diseases can get their start during childhood when the diseases betray few symptoms, the full impact of illness may not be felt until adulthood. A number of factors can uniquely affect children of African descent, heightening risk for some kids who already are predisposed to suffering more severe symptoms. These include:

  • Preterm birth. African American children make up 36 percent of patients in CKiD with glomerular disease, which tends to have faster progression to end-stage renal disease. These diseases impair kidney function by weakening glomeruli, which impairs the kidneys’ ability to clean blood. Patients with a high-risk apolipoprotein L1 (APOL1) genotype already are at higher risk for focal segmental glomerulosclerosis (FSGS) and CKD. Researchers hypothesize that preterm birth may represent “a second hit that facilitates the development of glomerular damage resulting from the high-risk genotype.” According to the Centers for Disease Control and Prevention, 1 in 10 U.S. infants in 2016 was born preterm, e.g., prior to 37 weeks gestation.
  • APOL1 genotype. Compared with children who had a low-risk genotype and FSGS, children with a high-risk genotype had higher rates of uncontrolled hypertension, left ventricular hypertrophy, elevated C-reactive protein levels and obesity.
  • Human immunodeficiency viral (HIV) status. About 65 percent of U.S. children with HIV-1/AIDS are African American. In a recent nested case-control study of children infected with HIV in the womb, infants with high-risk APOL1 genotypes were 3.5 times more likely to develop CKD with viral infection serving as “a likely second hit.”
  • Access to kidney transplant. African American adults experience a faster transition to end-stage renal disease and are less likely to receive kidney transplants. African American children with CKD from nonglomerular diseases begin renal replacement therapy 1.6 years earlier than children of other races, after adjusting for socioeconomic status. Their wait for dialysis therapy was 37.5 percent shorter. However, these African American children waited 53.7 percent longer for transplants. Although donor blood types, genetic characteristics and other biological factors each play contributing roles, “these findings may reflect sociocultural and institutional differences not captured by socioeconomic status,” Dr. Moxey-Mims writes.

To alleviate future health care disparities, she suggests that additional research explore the impact of expanding services to pregnant women to lower their chances of giving birth prematurely; early childhood interventions to help boost children’s educational outcomes, future job prospects and income levels; expanded studies about the impact of environmental toxicities on prenatal and postnatal development; and heightened surveillance of preterm infants as they grow older to spot signs of kidney disease earlier to slow or prevent disease progression.

“Clinicians can now begin to take into account genetics, socioeconomic status and the impact of the built environment, rather than blaming people and assuming that their behavior alone brought on kidney disease,” Dr. Moxey-Mims adds. “Smoking, not eating properly and not exercising can certainly make people vulnerable to disease. However, there are so many factors that go into developing a disease that patients cannot control: You don’t control to whom you’re born, where you live or available resources where you live. These research projects will be useful to help us really get to the bottom of which factors we can impact and which things can’t we prevent but can strive to mitigate.”

The article covered in this post is part of a supplement that arose from the Frank M. Norfleet Forum for Advancement of Health: African Americans and Kidney Disease in the 21st Century, held March 24, 2017, in Memphis, Tennessee. The Forum and the publication of this supplement were funded by the Frank M. Norfleet Forum for Advancement of Health, the Community Foundation of Greater Memphis and the University of Tennessee Health Science Center.