Propylthiouracil induced ANCA-associated vasculitis in a 14-year-old girl

Environmental factors influencing the risk of ANCA-associated vasculitis

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a group of diseases characterized by inflammation and destruction of small and medium-sized blood vessels. Clinical disease phenotypes include microscopic polyangiitis (MPA), granulomatosis with polyangiitis (GPA), and eosinophilic granulomatosis with polyangiitis (EGPA). The incidence of AAV has been on the rise in recent years with advances in ANCA testing. The etiology and pathogenesis of AAV are multifactorial and influenced by both genetic and environmental factors, as well as innate and adaptive immune system responses. Multiple case reports have shown that sustained exposure to silica in an occupational environment resulted in a significantly increased risk of ANCA positivity. A meta-analysis involving six case-control studies showed that silica exposure was positively associated with AAV incidence. Additionally, exposure to air pollutants, such as carbon monoxide (CO), is a risk factor for AAV. AAV has seasonal trends. Studies have shown that various environmental factors stimulate the body to activate neutrophils and expose their own antigens, resulting in the release of proteases and neutrophil extracellular traps, which damage vascular endothelial cells. Additionally, the activation of complement replacement pathways may exacerbate vascular inflammation. However, the role of environmental factors in the etiology of AAV remains unclear and has received little attention. In this review, we summarized the recent literature on the study of environmental factors, such as seasons, air pollution, latitude, silica, and microbial infection, in AAV with the aim of exploring the relationship between environmental factors and AAV and possible mechanisms of action to provide a scientific basis for the prevention and treatment of AAV.

Propylthiouracil-Induced Anti-Neutrophil Cytoplasmic Antibody Vasculitis Presenting with Red Eye Followed by Pulmonary Hemorrhage: Diagnostic and Management Considerations

Patient: Female, 34-year-old

Final Diagnosis: Vascuitis

Symptoms: Hemoptysis

Medication:—

Clinical Procedure: —

Specialty: Rheumatology

Study on the relationship between hyperthyroidism and vascular endothelial cell damage

The aim of the research is to explore the relationship between hyperthyroidism, iodine, antithyroid drugs (propylthiouracil) and vascular endothelial injury. In total, 136 SD rats were randomly allocated into the control group, the hyperthyroidism group, the hyperthyroidism propylthiouracil group, the hyperthyroidism low iodine group, the high iodine group, and the endothelial injury group. Rats were raised for 60 days. Afterward, indicators concerning endothelial damage were determined, including the von Willebrand Factor (vWF), thrombomodulin (TM), nitric oxide (NO), endothelin 1 (ET-1), and P-selectin, as well as the plant hemagglutinin sample type oxidized low-density lipoprotein receptor 1 (LOX-1) from the aorta and the number of endothelial progenitor cells (EPCs) in whole blood. The hyperthyroidism group had significantly higher values for vWF, TM, NO, ET-1, and P-selectin in serum and a higher number of EPCs in whole blood compared with the control group, similar to the LOX-1 expression in abdominal aorta. The hyperthyroidism low iodine group had significantly higher values for vWF, ET-1, and P-selectin in serum and a higher number of EPCs in whole blood compared with those of the control group, as was the case for LOX-1 expression in the abdominal aorta. The hyperthyroidism propylthiouracil group had significantly higher values for FT₄ in the serum compared with those in the control group. The electron microscope showed that hyperthyroidism caused a certain degree of endothelial injury to the abdominal aorta in rats. Hyperthyroidism can damage the vascular endothelium and is a high-risk factor for cardio-cerebrovascular disease. Propylthiouracil could be used in the treatment of hyperthyroidism, thus protecting endothelial cells from damage.