Dr Rajeewa Dassanayake1, Dr. Ramyasuda Swaminathan, Ms Sharon Ioh
1Fiona Stanley Hospital, Murdoch, Australia
Biography:
Senior Registrar in nephrology at Fiona Stanley Hospital. Former Consultant Nephrologist in Sri Lanka and presidential research award winner.
Background:
A young female with class V lupus nephritis and small bowel pseudo-obstructions with positive ganglionic acetylcholine receptor (gnACHR) antibodies improved with tacrolimus therapy.
Case report:
A 24-year-old female presenting with gastrointestinal symptoms and subsequent biopsy-proven mucocutaneous involvement, joint and pleuritic pains was diagnosed with Systemic Lupus Erythematosus (SLE) in 2018. Antinuclear and anti-double-stranded DNA antibodies were elevated (>30 and 13 IU/mL respectively) with low complement levels (C3 0.49g/L, C4 0.09g/L). Renal biopsy three years later for nephrotic syndrome with preserved glomerular filtration rate showed class V lupus nephritis with activity 0/24 and chronicity 0/12. Mycophenolate mofetil was continued with high dose steroids and hydroxychloroquine. Gastrointestinal symptoms and lack of renal efficacy necessitated changing mycophenolate mofetil to cyclophosphamide to a cumulative dose of 8g from February to September 2023. She had a renal flare upon cessation with peak anti-double-stranded DNA level 5120 IU/ml. Belimumab was started for seven months with mycophenolic acid, with a rapid resolution of nephrotic syndrome and drop in anti-double-stranded DNA to 100 with improvement in complement. However, there were recurrent presentations with migrating small bowel pseudo-obstruction demonstrated on imaging at distal jejunal and ileal sites. Intestinal biopsies were inconclusive. gnAHCR antibodies were strongly positive at 24%. Addition of tacrolimus in July 2024 resulted in sustained improvement in bowel symptoms.
Conclusion:
Lupus enteritis and autoimmune ganglionopathy are both associated with SLE and ghACHR antibodies. Both conditions are associated with gnAHCR antibodies. Lupus enteritis commonly involves distal jejunum and ileum. Both conditions require immunosuppression. Intestinal pseudo-obstruction presentations persisted despite previous multitarget immunosuppression but resolved with tacrolimus.