Glomerular tip lesion associated with nonsteroidal anti-inflammatory drug-induced nephrotic syndrome

Acute kidney injury associated with non-steroidal anti-inflammatory drugs

Non-steroidal anti-inflammatory drugs (NSAIDs) are ones of the commonly prescribed drugs worldwide. They primarily inhibit cyclooxygenase (COX) enzyme which is responsible for conversion of phospholipids to various prostaglandins (PGs). Disruption in PGs production affects the kidneys in several ways, including vasoconstriction that may result in ischemic acute kidney injury (AKI) in at-risk patients. They also impair salt and water excretion, leading to edema and hypertension. Other complications include hyperkalemia, hyponatremia, nephrotic syndrome, acute interstitial nephritis and chronic kidney disease progression. AKI from NSAIDs is usually reversible with favorable prognosis after discontinuation of NSAIDs. Avoidance of NSAIDs exposure is extremely important, especially among high-risk patients.

Complete remission of tip lesion variant focal segmental glomerulosclerosis (FSGS) with the Janus Kinase (JAK) inhibitor tofacitinib

A 67-year-old woman with transverse myelitis and seizure disorder secondary to suspected central nervous system (CNS) systemic lupus erythematosus (SLE) and seropositive rheumatoid arthritis had two episodes of severe nephrotic syndrome 15 years apart. She underwent a renal biopsy in both episodes, showing tip lesion variant focal segmental glomerulosclerosis (FSGS). The patient responded both times to prednisone treatment, achieving a complete remission within 2 months in the first episode and remission 4 months in the second episode. A year after her second episode, the patient had a third episode of severe nephrotic syndrome. She achieved an equally rapid complete remission in 3 months without steroid treatment, as she was concomitantly treated with the Janus Kinase (JAK) inhibitor tofacitinib for a flare of rheumatoid arthritis. This case report suggests that JAK inhibitors may have therapeutic use in FSGS, which is supported by experimental data in the medical literature.

Risk of Nephrotic Syndrome for Non-Steroidal Anti-Inflammatory Drug Users

BACKGROUND AND OBJECTIVES

Nonsteroidal anti-inflammatory drugs (NSAIDs) have been associated with AKI. Their association with nephrotic syndrome has not been systematically studied. This study aimed to assess the risk of nephrotic syndrome associated with NSAID use.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A matched case-control study was performed in the UK primary care database. Cases were patients with a first diagnosis of nephrotic syndrome and controls were those without nephrotic syndrome. NSAID exposure (grouped either based on cyclooxygenase enzyme selectivity and chemical groups) was classified as either current (use at the nephrotic syndrome diagnosis date and corresponding date in the control group), recent, or past use. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated using unconditional logistic regression analysis.

RESULTS

We included 2620 cases and 10,454 controls. Compared with non-use, current use of 15-28 days and >28 days of conventional NSAIDs was associated with a higher relative risk of nephrotic syndrome: adjusted OR, 1.34; 95% CI, 1.06 to 1.70, and OR, 1.42; 95% CI, 0.79 to 2.55, respectively. Also, recent use (discontinuation 1-2 months before nephrotic syndrome diagnosis date; OR, 1.55; 95% CI, 1.11 to 2.15) and past use (discontinuation 2 months-2 years; OR, 1.24; 95% CI, 1.07 to 1.43), but not current use of <15 days (OR, 0.78; 95% CI, 0.46 to 1.31) nor past use (discontinuation >2 years; OR, 0.96; 95% CI, 0.85 to 1.09) were associated with a higher relative risk of nephrotic syndrome as well as past use of selective COX-2 inhibitors (discontinuation 2-24 months; OR, 1.24; 95% CI, 0.98 to 1.58). Categorization based on chemical groups showed that acetic acid and propionic acid derivatives were associated with a higher risk of nephrotic syndrome.

CONCLUSIONS

The use of conventional NSAIDs was associated with a higher risk of nephrotic syndrome starting from at least 2 weeks of exposure, as well as for recent and past exposure up to 2 years before the diagnosis of nephrotic syndrome. This higher risk appeared mainly attributable to acetic acid and propionic acid derivatives.