Study in Focus 1:

Bacterial infection in patients with juvenile systemic lupus erythematosus and fever.

This case–control study involved 116 paediatric patients with systemic lupus erythematosus and fever, of whom 20 (17 %) had a confirmed bacterial infection.

The following predictors were evaluated:

• Recent use of immunomodulators or high‐dose corticosteroids.
• Renal support: Requirement for renal replacement therapy.
• Acute‐phase reactants:
  • Erythrocyte sedimentation rate (ESR) > 20 mm/hr
  • C-reactive protein (CRP) > 60 mg/L and > 90 mg/L
  • Ferritin > 500 ng/mL
• Cell‐count ratios:
  • Neutrophil-to-lymphocyte ratio (NLR) > 6
  • Platelet-to-lymphocyte ratio (PLR) > 133
  • Lymphocyte-to-C4 ratio (LC4R) > 66.7
• Infection markers: Procalcitonin (PCT) > 0.9 ng/mL
• Composite index: ESR/CRP ratio < 2

In the study, 17% of febrile JSLE episodes were bacterial. The most frequently involved system was the urinary tract, and isolated organisms included Escherichia coli and Staphylococcus aureus. On multivariate analysis, only PCT > 0.9 ng/ml remained a significant independent predictor (p < 0.01). Procalcitonin is a key marker, with a PCT threshold of 0.9 ng/ml, that is highly suggestive of bacterial infection in JSLE patients with fever. Other markers warrant further study, including NLR, PLR, LC4R, ESR/CRP ratio, and ferritin, which showed univariate associations but require additional data to establish robust cut-off values. Individualised assessment remains essential, and no single biomarker (aside from PCT) can fully distinguish infection from disease flare in all cases.¹

Study in Focus 2:

Paediatric non-infectious granulomatous uveitis: a retrospective cohort study.

Paediatric granulomatous uveitis (PGU) is a rare and often under-recognized condition. This retrospective study conducted at Bicêtre Hospital in France between 2001 and 2023 is the largest known cohort of PGU. A total of 50 patients were included: 29 with idiopathic uveitis, 15 with sarcoidosis, 5 with juvenile idiopathic arthritis (JIA), and 1 with Vogt-Koyanagi-Harada disease. The median age at diagnosis was 9.8 years, with a female predominance. The most frequent presentation was panuveitis (56%), followed by bilateral (84%) and chronic (84%) disease. Sarcoidosis emerged as the most common identified cause after idiopathic cases, particularly in patients with lymphopenia and hypergammaglobulinemia. Uveo-meningitis was observed in 12% of cases. At diagnosis, ocular complications were present in 76% of affected eyes, especially those with panuveitis. Systemic corticosteroids (72%) and methotrexate (80%) were the most commonly used treatments. After a median follow-up of 5.8 years, 23% of patients were in remission, 68% had inactive disease, and 4% continued to have active disease. Early initiation of disease-modifying therapy, particularly in sarcoid and idiopathic panuveitis, was essential for optimal disease control and preserving vision.²

References:

1. Gómez-Urrego JF, Yepes-Madrid N, Gil-Artunduaga MA, Del Pilar Gómez-Mora M, Mejía-Rivera LF, Pacheco-López R, et al. Bacterial infection in patients with juvenile systemic lupus erythematosus and fever. PediatrRheumatol Online J. 2025;23(1):39.
2. Nguyen AT, Rousseau A, Bodaghi B, Rossi-Semerano L, Galeotti C, Da Cunha E, et al. Paediatric non-infectious granulomatous uveitis: a retrospective cohort study. Rheumatology (Oxford). 2025;64(3):1333-40.