免疫性血小板減少症

Coronary artery anomalies (CAAs) are rare congenital variations with a broad spectrum of clinical implications. While certain configurations are associated with myocardial ischemia and sudden cardiac death (SCD), many remain clinically silent and are discovered incidentally. An anomalous origin of the left main coronary artery (LMCA) from the right coronary artery (RCA) represents an exceptionally uncommon variant, particularly when it arises from the proximal RCA and follows a prepulmonic course. We report the case of a 56-year-old female with a history of immune thrombocytopenic purpura who presented with atypical chest discomfort. She underwent coronary computed tomography angiography (CCTA), which revealed an LMCA originating from the proximal RCA with a prepulmonic (anterior) course, consistent with a Lipton right sinus of valsalva, type II, anterior (RIIA) single coronary artery (SCA) pattern. The coronary artery calcium score was zero, and no evidence of obstructive coronary artery disease was identified. Given the absence of ischemia and the benign anatomical course, the patient was managed conservatively. She underwent periodic outpatient surveillance with symptom reassessment and cardiovascular risk factor monitoring, remaining asymptomatic over three years without adverse cardiac events. Single coronary artery anomalies are rare, with reported prevalence estimates of approximately 0.06% in angiographic series, although these data may be influenced by referral bias. Among these, LMCA arising from the RCA accounts for only 0.0024%-0.02% of reported cases. Clinical significance depends on vessel course as well as associated morphological features. Interarterial variants carry higher risk, whereas prepulmonic and retroaortic courses are generally considered lower risk. CCTA is valuable for defining anatomy and guiding individualized risk stratification, while functional testing may be considered selectively when symptoms or uncertain hemodynamic significance are present. This case highlights a rare but benign coronary anomaly and underscores the importance of integrating anatomical findings, clinical presentation, and selective adjunctive testing to guide management while avoiding unnecessary invasive intervention.

RATIONALE: Systemic lupus erythematosus (SLE)-associated thrombotic microangiopathy with features of atypical hemolytic uremic syndrome (aHUS) is a rare but life-threatening complication. Early recognition is challenging because of its overlapping clinical manifestations with other thrombotic microangiopathies. PATIENT CONCERNS: A 49-year-old man with SLE presented with anemia, thrombocytopenia, and multi-system involvement. Despite initial immunosuppressive therapy, his hematologic parameters progressively deteriorated, with hemoglobin decreasing to 89 g/L and the platelet count to 54 × 109/L. DIAGNOSES: Laboratory investigations demonstrated elevated lactate dehydrogenase (501 U/L) and markedly increased soluble complement membrane attack complex (sC5b-9, >1790 ng/mL). ADAMTS13 activity was normal (75.41%), excluding thrombotic thrombocytopenic purpura. Based on the clinical and laboratory findings, the patient was diagnosed with SLE-associated aHUS. INTERVENTIONS: Following the diagnosis, the patient received eculizumab, a monoclonal antibody targeting complement component C5. OUTCOMES: Within 6 days of eculizumab treatment, hemoglobin increased to 102 g/L, and the platelet count recovered to 108 × 109/L, indicating a rapid hematologic response. LESSONS: This case highlights that aHUS can occur as a severe complication of SLE, even in male patients. Complement-mediated thrombotic microangiopathy may coexist with and be triggered by immune hemolysis in SLE. Early recognition and prompt complement inhibition with eculizumab can produce an ultra-rapid hematologic response and may be critical for improving patient outcomes.

BACKGROUND: Immune thrombocytopenic purpura (ITP) is the most common autoimmune bleeding disorder in children and poses a serious threat to pediatric health and survival. An imbalance in Th17 and Treg cell differentiation leads to uncontrolled inflammation. METHODS: Peripheral blood mononuclear cells and CD4+ T cells were isolated from 23 ITP patients and 23 healthy controls. Th17 and Treg proportions were quantified by flow cytometry, and serum concentrations of IL-17 A, IL-10, IL-22, IL-23, IL-6, and TNF-α were measured by ELISA. An ITP mouse model was established by splenocyte transfer, and AhR antagonism was evaluated using CH-223191. AhR SUMOylation was assessed by co-immunoprecipitation and western blot, and transcriptional activity was determined by dual-luciferase reporter assay. RESULTS: The Th17/Treg ratio was significantly elevated in ITP patients compared with controls (P < 0.001), accompanied by increased serum IL-17 A, IL-22, IL-23, IL-6, and TNF-α and decreased IL-10 (P < 0.001). AhR mRNA and protein expression were markedly upregulated in ITP CD4+ T cells (P < 0.001). Inhibition of AhR by CH-223191 reduced the Th17 proportion from 3.5% to 2.0% and increased the Treg proportion from 1.2% to 2.8%, normalizing the Th17/Treg ratio (P < 0.001). Consistent results were observed in vivo, with improved platelet counts and restored Th17/Treg balance. Mechanistically, AhR underwent SUMOylation at K63 and K510 by SUMO1, which enhanced AhR protein stability and transcriptional activity; this modification was reversed by SENP1-mediated deSUMOylation. CONCLUSION: Blocking AhR, which is modified by SUMO1 and deSUMOylated by SENP1, alleviates ITP-induced Th17/Treg imbalance through SENP1-mediated deSUMOylation.

INTRODUCTION: Autoimmune cytopenias have been very rarely reported in conjunction with POEMS (polyneuropathy, organomegaly, endocrinopathy, M-protein, and skin changes syndrome). To the best of our knowledge, there is no reported case in the existing literature of an association of Evans syndrome with POEMS syndrome. CASE DESCRIPTION: A 55-year-old female patient, with a medical history of well-controlled dermatomyositis, developed fulminant autoimmune haemolytic anaemia with immune thrombocytopenic purpura, thus fulfilling the diagnosis of Evans syndrome. To control the disease, acute management required supportive measures in the intensive care unit, repeated transfusions of red blood cells and platelets, high- dose intravenous corticosteroids, a bolus of cyclophosphamide, and splenectomy. Three days post-splenectomy, the patient developed, subacutely, full-blown POEMS syndrome. Therefore, the diagnosis of coexisting secondary Evans syndrome and POEMS syndrome was made. Notably, the monoclonal kappa light chain restriction and multiple splenic infarctions were distinctive features in our patient. Due to procurement issues of lenalidomide, we opted for monthly parenteral cyclophosphamide and autologous stem cell transplantation was programmed. CONCLUSION: This case highlights that severe secondary Evans syndrome can coexist with POEMS syndrome, leading to challenges in diagnosis and management. LEARNING POINTS: Severe secondary Evans syndrome can coexist with POEMS (polyneuropathy, organomegaly, endocrinopathy, M-protein, and skin changes) syndrome.High doses of corticosteroids required for the acute management of Evans syndrome may artificially lower the genuine value of serum vascular endothelial growth factor in the context of associated POEMS syndrome.In atypical circumstances like in our case (associated Evans syndrome, kappa light chain restriction), the nerve biopsy is critical to exclude differential diagnoses and confirm typical characteristics of POEMS syndrome- related polyneuropathy.