Clinical presentation of children with lupus nephritis from a low- and middle-income country (LMIC): an initial report from the Indian pSLE Nephritis Registry.

INTRODUCTION

Limited prospective data exist on pediatric LN (pLN) from low- and middle-income countries (LMIC), where ethnicity, socioeconomic factors, and healthcare access are likely to differ from high-income countries.

METHODS

The Indian Pediatric Lupus Nephritis registry has been running since 2020 across multiple centers in India. Children (≤ 18 years) diagnosed with lupus (as per 2012 SLICC criteria), presenting with nephritis, and confirmed by kidney biopsy are being prospectively enrolled. Clinical data, laboratory investigations, kidney biopsy results, and treatment responses have been documented prospectively. The current report documents their initial presentation.

RESULTS

A total of 154 children (75% female, median age 12 years-IQR 10-14 years) with biopsy-proven LN were enrolled by July 2024. Nearly two-thirds had LN at SLE diagnosis, and the rest developed within a maximum of 5 years of initial presentation. Common manifestations at presentation included edema (75%), hypertension (54%), and proteinuria (98%), of which 68% presented with nephrotic-range proteinuria. Acute kidney injury (AKI) was observed in 43%, with 20% in stage 3. Ninety-four percent of our cohort had low complements (C3, C4, or both), and 96% were ANA-positive. Class IV LN was the most common (45%) histopathological type and had significantly lower estimated glomerular filtration rate in comparison to Class V LN.

CONCLUSION

Kidneys are often involved in the initial presentation of childhood lupus, and the majority have proliferative nephropathy leading to AKI, hypertension, and significant proteinuria. Children enrolled in the registry are under active follow-up to assess the renal responses which will help optimize the management of pLN in LMICs. Key Points •It is a well-known fact that kidney involvement is more common in pediatric lupus and is among one of the most important long-term prognostic factors. •There is scarcity of data on pediatric lupus nephritis (pLN) particularly from low- and middle-income countries (LMIC), and even among them, the majority of the studies are retrospective and limited by a small cohort size. •Through this prospective registry from a LMIC, we demonstrated that 2/3rd of children with lupus have kidney involvement at presentation and almost all (90%) develop LN within 2 years of the diagnosis of lupus. •Acute kidney injury (AKI) is known to increase mortality/morbidity risks independently. Many of the previous studies have under-reported AKI in pLN, probably because the data was collected retrospectively. On the other hand, we found AKI to be very common and to be present in about half of the cases at presentation.