Outcome of critically ill patients with systemic lupus erythematosus from a medical intensive care unit in Southern India

Abstract

Objective

Systemic lupus erythematosus (SLE) has become the most prevalent autoimmune condition requiring admission in the intensive care units (ICU) in the last two decades. Here we analysed the clinical outcomes of SLE patients admitted to our ICU between 2011 and 2021, and studied the prognostic role of high-density lipoprotein (HDL) and procalcitonin in those enrolled after August 2019.

Methods

Systemic lupus erythematosus (ACR/SLICC 2012) were enrolled, 72 retrospectively and 30 prospectively. Data on indications for ICU admission, complications, infections, and disease activity were recorded. Outcome was mortality at 90 days (prospective) whereas in the retrospective analysis outcome was hospital discharge or death in hospital. Serum HDL and procalcitonin (PCT) was estimated in the prospectively enrolled 30 patients and compared with 30 non ICU-SLE patients.

Results

Indications for ICU admissions were respiratory causes in 78/102 (76.5%) patients; for haemodynamic monitoring and for invasive procedures in the remaining. Pneumonia was the primary reason for mechanical ventilation, followed by diffuse alveolar haemorrhage (DAH). Eighty-three (81.3%) patients died; infections (n = 54) and SLE related causes (n = 29). APACHE-II >16 (p = .026), lymphopenia (p = .021), infection (p = .002), creatinine >1.3 mg/dL (p = .023), and hypotension requiring vasopressor support (p = .006) emerged as significant predictors of non-survival on multivariable analysis. HDL (mg/dL) day 1 was significantly lower in SLE-ICU patients compared to non ICU-SLE (31.8 ± 14.3 vs 38.8 ± 11.4 mg/dl); p = .045. On day 1, PCT (ng/mL) in SLE-ICU was significantly higher when compared to non-ICU SLE; median (IQR): 0.53 (0.26–5.27) versus 0.13 (0.05–0.47), p < .001), respectively. It was also significantly higher on day 5 in SLE-ICU than non-ICU SLE (median (IQR): 4.18 (0.20–14.67) versus 0.10 (0.08–0.46), p = .004.

Conclusion

The mortality of SLE patients admitted to the ICU in this study is high, and infections were the principal reason for death. Baseline low HDL and higher procalcitonin are potential biomarkers to identify critically ill SLE patients.