Scrub Typhus-Induced Macrophage Activation Syndrome with Flare of Systemic Lupus Erythematosus: A Rare Case Report

Aims: Infection is a major trigger for both Lupus flare and Macrophage activation syndrome. Scrub typhus infection associated with lupus flare or MAS has been very rarely reported. We report a case of scrub typhus-induced MAS along with a flare of disease activity in a neuropsychiatric lupus patient presenting after discontinuation of medications.

Presentation of Case: 13-year-old girl, a known case of neuropsychiatric lupus with lupus nephritis, on immunosuppressant for the last 1 year had stopped all medications for 3 months. She had presented with a fever and altered sensorium. Based on clinical and laboratory investigations, a diagnosis of scrub typhus-induced macrophage activation syndrome with a flare of lupus disease activity was made and the patient was treated with injection doxycycline and glucocorticoids. There was rapid clinical improvement with treatment.

Discussion: The case emphasizes the importance of identifying the exact trigger behind the deterioration of a patient with lupus and its therapeutic implications. An infection alone requires antibiotics only, flare without infection requires up titrating immunosuppressants but the presence of life-threatening complications like MAS along with infection requires prompt treatment of both facets simultaneously.

Conclusion: Scrub typhus infection should be ruled out apart from other common infections in any patient with lupus flare or MAS.