Epitope analysis of anti-myeloperoxidase antibodies in propylthiouracil-induced antineutrophil cytoplasmic antibody-associated vasculitis

Correlation between thyroid autoantibodies and cardiovascular disease in patients with stages 3-5 chronic kidney disease

Background

Chronic kidney disease (CKD) is associated with thyroid disease and cardiovascular disease (CVD). To date, little is known about the association of thyroid autoantibodies with renal function or cardiac function in patients with CKD.

Methods

This is a descriptive cross-sectional study. Patients diagnosed with stages 3-5 CKD from January 2015 to May 2019 at our department were recruited. Routine medical history, general clinical data, and laboratory test indexes were collected for all patients. Echocardiography was performed by a trained echocardiographer to measure E in early diastole and A, E/A ratio, E' in early diastole, A' in end-diastole, E/E' ratio, and E'/A' ratio.

Results

A total of 1,164 patients with stages 3-5 CKD were included. Thyrotropin receptor antibody (TRAb) was significantly positively correlated with C-reactive protein (r=0.206, P<0.001). Thyroid peroxidase antibody (TPOAb) and TGAb titers in male diabetic patients were higher (r=0.137, P=0.023; r=0.159, P=0.011). In female patients, both TPOAb and TGAb were significantly negatively correlated with hemoglobin (r=-0.213, P=0.018; r=-0.188, P=0.019). The E/E' of patients who were TPOAb positive was higher than that in patients with TPOAb negative (r=0.181, P<0.001). LVEF in patients who were TPOAb positive was higher than that in patients with TPOAb negative (r=0.159, P=0.007). In addition, LVEF was significantly negatively correlated with TRAb (r=-0.112, P=0.026).

Conclusions

In patients with stages 3-5 CKD, AITD may increase the risk of CVD in CKD patients by affecting triglycerides levels, increasing the risk of anemia, and promoting micro-inflammation. Attention should be paid to female patients with high TPOAb and TGAb titers. The mean of E/E' in patients with stage 5 CKD was 16.89 in the present study. Women with TPOAb positive may be more likely to develop diastolic heart failure.

Systemic p-ANCA vasculitis with fatal outcome, arising in the setting of methimazole use

Here we report a fatal case of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) due to methimazole use in a 64-year-old woman. She was initially hospitalized for abdominal pain and possible colitis, and subsequently developed hematuria, renal failure, and hemoptysis. The serologic work-up revealed positive antinuclear antibody (ANA) and perinuclear-antineutrophilic cytoplasm antibodies (p-ANCA), with positive antimyeloperoxidase. Three weeks following admission, the patient was found to be pulseless, and expired. At autopsy, microscopic review included widespread transmural necrotizing vasculitis and crescentic glomerulonephritis in the kidney, and diffuse pulmonary alveolar hemorrhage; focal coronary artery intimal vasculitis and necrotizing pericarditis were also noted. Several drugs have been associated with the development of ANCA-positive diseases, including propylthiouracil, hydralazine, allopurinol, penicillamine, and levamisole in cocaine. Association of ANCA vasculitis with methimazole exposure is less known, and severe presentation with fatal outcome, as seen in our patient, is exceedingly rare. We reviewed clinical and histopathologic features of drug-induced ANCA vasculitis associated with methimazole to raise awareness of this potentially life-threatening complication associated with this agent.

Propylthiouracil-induced Otitis Media with Antineutrophil Cytoplasmic Antibody-associated Vasculitis

We herein report a case of otitis media with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (OMAAV) induced by propylthiouracil (PTU). A 30-year-old Japanese woman with Graves' disease, who was treated with PTU, reported with otitis media with sensorineural hearing loss bilaterally and trigeminal neuralgia on the left side, as well as elevated serum levels of myeloperoxidase-ANCA. Prior treatment with antibiotics was ineffective even after tympanostomy. However, clinical remission was immediately achieved after initiating prednisolone together with PTU withdrawal. These findings suggest that PTU therapy induces localized otological involvement as the concept of OMAAV.

Drug-induced nephropathies

Drugs are associated frequently with the development of various types of acute and chronic kidney diseases. Nephrotoxicity is associated most commonly with injury in the tubulointerstitial compartment manifested as either acute tubular injury or acute interstitial nephritis. A growing number of reports has also highlighted the potential for drug-induced glomerular disease, including direct cellular injury and immune-mediated injury. Recognition of drug-induced nephropathies and rapid discontinuation of the offending agents are critical to maximizing the likelihood of renal function recovery. This review will focus on the pathology and pathogenesis of drug-induced acute interstitial nephritis and drug-induced glomerular diseases.

Antineutrophil Cytoplasmic Antibody-Positive Small-Vessel Vasculitis Associated with Antithyroid Drug Therapy: How Significant Is the Clinical Problem?

BACKGROUND

The aim of this review was to delineate the characteristics of antineutrophil cytoplasmic antibody (ANCA)-associated small-vessel vasculitis associated with antithyroid drugs (ATD). A PubMed search was made for English language articles using the search terms antithyroid drugs AND ANCA OR ANCA-associated vasculitis.

SUMMARY

The literature includes approximately 260 case reports of ANCA-associated small-vessel vasculitis related to ATD, with 75% of these associated with thiouracil derivatives (propylthiouracil [PTU]) and 25% with methyl-mercapto-imidazole derivatives (MMI/TMZ). The prevalence of ANCA-positive cases caused by ATD varied between 4% and 64% with PTU (median 30%), and 0% and 16% with MMI/TMZ (median 6%). Young age and the duration of ATD therapy were the main factors contributing to the emergence of ANCA positivity. Before ATD therapy initiation, the prevalence of ANCA-positive patients was 0-13%. During ATD administration, 20% of patients were found to be positive for ANCA. Only 15% of ANCA-positive patients treated with ATD exhibited clinical evidence of vasculitis, corresponding to 3% of all patients who received ATD. Clinical manifestations of ANCA-associated vasculitis related to ATD were extremely heterogeneous. When vasculitis occurred, ATD withdrawal was usually followed by rapid clinical improvement and a favorable prognosis.

CONCLUSIONS

ANCA screening is not systematically recommended for individuals on ATD therapy, particularly given the decreasing use of PTU in favor of TMZ/MMI. Particular attention should be given to the pediatric population with Graves' disease who receive ATD, as well as patients treated with thiouracil derivatives and those on long-term ATD therapy.

Clinical and Immunologic Characteristics of Patients With ANCA-Associated Glomerulonephritis Combined With Membranous Nephropathy: A Retrospective Cohort Study in a Single Chinese Center

The concurrent antineutrophil cytoplasmic antibody-associated glomerulonephritis (ANCA-GN) and membranous nephropathy (MN) have been increasingly documented, mainly in case studies and case series; however, the differences of clinical and pathologic characteristics as well as outcomes between ANCA-GN patients with and without MN remain unclear. The current study investigated the clinical and immunologic features of patients with combined ANCA-GN and MN in a large cohort. Twenty-seven of 223 patients had combined ANCA-GN and MN; they had significantly higher levels of initial serum creatinine, higher Birmingham Vasculitis Activity Score and poorer renal outcome than ANCA-GN patients without MN (P < 0.05). ANCA-GN patients with MN could recognize the light chain of myeloperoxidase more frequently than those without MN (P < 0.05). The prevalence of circulating anti-PLA2R antibodies and glomerular PLA2R deposits was significantly lower in patients with combined ANCA-GN and MN than that in patients with idiopathic MN (P < 0.05). Compared with the idiopathic MN patients, the patients with combined ANCA-GN and MN had significantly higher recognition frequency of immunoglobulin (Ig) G2 and IgG3, and significantly lower recognition frequency of IgG4 (P < 0.05). Patients with combined ANCA-GN and MN had distinct clinical features and a different pathogenesis of MN.

Drug-induced glomerular disease: immune-mediated injury

Drug-induced autoimmune disease was initially described decades ago, with reports of vasculitis and a lupus-like syndrome in patients taking hydralazine, procainamide, and sulfadiazine. Over the years, multiple other agents have been linked to immune-mediated glomerular disease, often with associated autoantibody formation. Certain clinical and laboratory features may distinguish these entities from their idiopathic counterparts, and making this distinction is important in the diagnosis and management of these patients. Here, drug-induced, ANCA-associated vasculitis, drug-induced lupus, and drug-associated membranous nephropathy are reviewed.