CLINICOPATHOLOGICAL CHARACTERISTICS OF LUPUS NEPHRITIS AT A TERTIARY CARE CENTER IN NIGERIA

Introduction:

Lupus nephritis is a treatable form of chronic kidney disease that can be identified by its histological characteristics. However, there is currently insufficient documentation of the clinical and histopathological patterns of lupus nephritis in most countries of Africa. The study aims to describe the clinical and histological characteristics of patients with lupus nephritis at a tertiary care center in Nigeria as well as their association.

Methods:

We conducted a cross-sectional study involving 30 patients with lupus nephritis recruited consecutively from December 2021 to June 2022. Participants were patients with lupus who had persistent proteinuria of more than 500mg per day and/or the presence of cellular cast or more than 5 red blood cells per high power field on urine microscopy. However, patients with morbid obesity, kidney allograft, bleeding diathesis, or those on dialysis were excluded. To estimate the glomerular filtration rate (eGFR), we utilized the Chronic Kidney Disease Epidemiology Collaboration equation (CKD-EPI), which is based on serum creatinine levels. The urine protein was measured and expressed as the urine protein-creatinine ratio. Furthermore, each participant had a kidney biopsy and the tissues were analyzed using light microscopy and immunohistochemistry. To determine the correlation between clinical and histological characteristics, we employed the Spearman correlation method. The histological diagnosis was based on the International Society of Nephrology/Renal Pathology Society(ISN/RPS) classification.

Results:

The mean age of patients was 31.73±10.52 years, and there was a female preponderance (90%). The most common clinical features reported were joint pains (90%), joint stiffness (76.7%), fatigue (60%), and frothy urine (60%). Twenty-six patients (86.7%) had a histological diagnosis of lupus nephritis based on the ISN/RPS classification (Table 1). Other histological diagnoses were chronic tubulointerstitial nephritis (10%) and acute interstitial nephritis (3.3%). A positive correlation was found between worsening proteinuria and increasing histological classes (r = 0.751, p < 0.001), while the estimated glomerular filtration rate showed an inverse correlation (r = -0.656, p= 0.005).

Conclusions:

The most common histological patterns of lupus nephritis were ISN/RPS classes I, II, and IV. Worsening proteinuria was found to be associated with an increase in histological classes.

I have no potential conflict of interest to disclose.

I did not use generative AI and AI-assisted technologies in the writing process.