Abstract:

Thrombocytopenia is one of the most common hematological complications of systemic lupus erythematosus (SLE). In severe cases, it can lead to life-threatening complications such as intracranial hemorrhage, significantly affecting the prognosis of patients. Clinically, after treatment with standard-dose glucocorticoids combined with immunosuppressants (e.g., cyclophosphamide, mycophenolate mo-fetil, etc.), the platelet count of most patients can rapidly increase and remain stable. However, there are still some refractory patients who do not respond to traditional treatment and require advanced therapeutic regimens such as biological agents or thrombopoietin receptor agonists (TPO-RAs). This article reports a case of a 38-year-old young female patient with SLE. By the 17th week of her pregnancy, severe thrombocytopenia (9×10⁹/L) was detected. Laboratory tests showed an antinuclear antibody (ANA) titer of 1 ∶ 320, decreased complement C3, and elevated antiphospholipid antibodies. Additionally, she had a popliteal vein thrombosis in the right lower extremity. Bone marrow aspiration indicated a disorder in the differentiation and maturation of megakaryocytes. The patient was diagnosed with SLE, secondary immune thrombocytopenia, and antiphospholipid syndrome. At the end of 21 weeks of gestation, the patient underwent a cesarean section to terminate the pregnancy due to concurrent asymptomatic pulmonary embolism and pulmonary hypertension. During the entire disease course, the patient only had a transient response (duration no more than 1 week) to intravenous immunoglobulin (IVIG) or high-dose glucocorticoid pulse therapy. She showed no response to conventional-dose glucocorticoids (methylprednisolone 40-80 mg/d), immunosuppressants (such as tacrolimus, mycophenolate mofetil, and sirolimus), rituximab, and TPO-RAs (e.g., eltrombopag). The platelet count persistently fluctuated between 1×10⁹/L and 10×10⁹/L, accompanied by intermittent gingival and vaginal bleeding. Intermittent IVIG infusions and subcutaneous injection of leuprolide acetate for artificial amenorrhea were required for treatment. Finally, after the patient received avatrombopag 20 mg once daily for 5 days, the platelet count rapidly increased to the normal range and remained stable for a relatively long period. This case suggests that TPO-RAs can be an effective treatment option for patients with refractory SLE complicated by thrombocytopenia who are unresponsive to traditional therapies. Additionally, there are differences in response among different TPO-RAs, and switching to another TPO-RA may yield favorable therapeutic effects. This provides a new practical reference for the individualized treatment of such refractory cases in clinical practice.

Key words: Systemic lupus erythematosus, Thrombocytopenia, Thrombopoietin receptor agonist, Avatrombopag