Antineutrophil cytoplasmic antibodies in patients treated with methimazole: a prospective Brazilian study / Anticorpos anticitoplasma de neutrófilos em pacientes tratados com metimazol: um estudo prospectivo brasileiro

Abstract Introduction: The side effects of antithyroid drugs are well known. Antineutrophil cytoplasmic antibody-associated vasculitis is a severe adverse reaction. Most studies evaluating antineutrophil cytoplasmic antibodies related to antithyroid drugs have been carried out with patients treated with propylthiouracil, but less information is available for methimazole. Furthermore, most studies that investigated antineutrophil cytoplasmic antibodies related to antithyroid drugs were conducted on Asian populations. Objective: To evaluate the frequency of antineutrophil cytoplasmic antibodies and antineutrophil cytoplasmic antibodies-positive vasculitis in an adult population of Brazilian patients treated with methimazole. Methods: This was a prospective study. We evaluated patients ≥18 years with Graves' disease who have been using methimazole for at least 6 months (Group A, n = 36); with Grave's disease who had been previously treated with methimazole but no longer used this medication for at least 6 months (Group B, n = 33), and with nodular disease who have been using methimazole for at least 6 months (Group C, n = 13). Results: ANCA were detected in 17 patients (20.7%). Four patients (4.9%) had a strong antineutrophil cytoplasmic antibodies-positive test. The frequency of antineutrophil cytoplasmic antibodies was similar in the groups. When Groups A and B were pooled and compared to Group C to evaluate the influence of Grave's disease, and when Groups A and C were pooled and compared to Group B to evaluate the influence of methimazole discontinuation, no difference was found in the frequency of antineutrophil cytoplasmic antibodies. No difference was observed in sex, age, etiology of hyperthyroidism, anti-TSH receptor antibodies, dose or time of methimazole use between patients with versus without antineutrophil cytoplasmic antibodies. The titers of these antibodies were not correlated with the dose or time of methimazole use. None of the antineutrophil cytoplasmic antibodies-positive patient had clinical event that could potentially result from vasculitis. Conclusion: This clinical study of a Brazilian population shows a considerable frequency of antineutrophil cytoplasmic antibodies in patients treated with methimazole but the clinical repercussion of these findings remains undefined.

Resumo Introdução: Os efeitos adversos de drogas antitireoidianas são conhecidos. Vasculite associada a anticorpos anticitoplasma de neutrófilos é uma reação adversa grave. A maioria dos estudos que avaliam anticorpos anticitoplasma de neutrófilos relacionado a drogas antitireoidianas envolveu pacientes tratados com propiltiouracil, entretanto menos informação se encontra disponível para o metimazol. Além disso, a maioria dos estudos que investigaram anticorpos anticitoplasma de neutrófilos relacionado a drogas antitireoidianas foi conduzida em populações asiáticas. Objetivo: Avaliar a frequência de anticorpos anticitoplasma de neutrófilos e vasculite anticorpos anticitoplasma de neutrófilos-positivo em uma população adulta de pacientes brasileiros tratados com metimazol. Método: Este foi um estudo prospectivo. Avaliamos pacientes ≥ 18 anos com doença de Graves com o uso de metimazol há pelo menos seis meses (Grupo A, n = 36); com doença de Graves previamente tratados com metimazol, mas que não usaram esse medicamento por pelo menos seis meses (Grupo B, n = 33) e com doença nodular em uso de metimazol há pelo menos seis meses (Grupo C, n = 13). Resultado: Anticorpos anticitoplasma de neutrófilos foram detectados em 17 pacientes (20,7%). Quatro pacientes (4,9%) tinham anticorpos anticitoplasma de neutrófilos fortemente positivos. A frequência de anticorpos anticitoplasma de neutrófilos foi semelhante nos grupos. Quando os Grupos A e B foram somados e comparados ao Grupo C para avaliar a influência da doença de Graves, e quando os Grupos A e C foram somados e comparados ao Grupo B para avaliar a influência da interrupção do metimazol, não foi encontrada diferença na frequência de anticorpos anticitoplasma de neutrófilos. Não houve diferença em relação a sexo, idade, etiologia do hipertireoidismo, anticorpos antirreceptor de TSH, dose ou tempo de uso de metimazol entre pacientes com e sem anticorpos anticitoplasma de neutrófilos. Os títulos desses anticorpos não se correlacionaram com dose ou tempo de uso de metimazol. Nenhum paciente anticorpos anticitoplasma de neutrófilos-positivo apresentou evento clínico resultante de vasculite. Conclusão: Este estudo clínico de uma população brasileira apresenta frequência considerável de anticorpos anticitoplasma de neutrófilos em pacientes tratados com metimazol, mas a repercussão clínica desse achado permanece indefinida.

Hydralazine-associated adverse events: a report of two cases of hydralazine-induced ANCA vasculitis / Eventos adversos associados à hidralazina: um relatório de dois casos de vasculite associada ao ANCA induzida por hidralazina

Abstract Hydralazine is a direct-acting vasodilator, which has been used in treatment for hypertension (HTN) since the 1950s. While it is well known to cause drug-induced lupus (DIL), recent reports are indicating the emergence of the drug-induced anti-neutrophil cytoplasmic antibody (ANCA) associated vasculitis (DIV). Herein, we describe two patients (aged 57 and 87 years) who presented with severe acute kidney injury (AKI), proteinuria, and hematuria. Both were receiving hydralazine for the treatment of hypertension. ANCA serology was positive in both patients along with anti-histone antibodies (commonly seen in drug-induced vasculitis). Renal biopsy revealed classic crescentic (pauci-immune) glomerulonephritis in these patients and hydralazine was discontinued. During the hospital course, the 57-year-old patient required dialysis therapy and was treated with steroids and rituximab for the ANCA disease. Renal function improved and the patient was discharged (off dialysis) with a serum creatinine of 3.6 mg/dL (baseline = 0.9 mg/dL). At a follow-up of 2 years, the patient remained off dialysis with advanced chronic kidney disease (CKD) (stage IIIb). The 87-year-old patient had severe AKI with serum creatinine at 10.41 mg/dL (baseline = 2.27 mg/dL). The patient required hemodialysis and was treated with steroids, rituximab, and plasmapheresis. Unfortunately, the patient developed catheter-induced bacteremia and subsequently died of sepsis. Hydralazine can cause severe AKI resulting in CKD or death. Given this extremely unfavorable adverse-event profile and the widespread availability of alternative anti-hypertensive agents, the use of hydralazine should be carefully considered.

Resumo A hidralazina é um vasodilatador de ação direta, que vem sendo utilizado no tratamento da hipertensão arterial (HA) desde a década de 1950. Embora seja bem conhecido por causar lúpus induzido por drogas (LID), relatórios recentes estão indicando o surgimento da vasculite associada ao anticorpo citoplasmático anti-neutrófilo (ANCA), induzida por drogas (VID). Aqui, descrevemos dois pacientes (com idade entre 57 e 87 anos) que apresentaram lesão renal aguda grave (LRA), proteinúria e hematúria. Ambos estavam usando hidralazina para o tratamento da hipertensão. A sorologia para ANCA foi positiva em ambos os pacientes, juntamente com anticorpos anti-histona (comumente vistos na vasculite induzida por drogas). A biópsia renal revelou glomerulonefrite rapidamente progressiva clássica (pauci-imune) nestes pacientes e a hidralazina foi interrompida. Durante a internação hospitalar, o paciente de 57 anos necessitou de diálise e foi tratado com esteroides e rituximab para a doença do ANCA. A função renal melhorou e o paciente recebeu alta (fora da diálise) com creatinina sérica de 3,6 mg/dL (basal = 0,9 mg/dL). Em um seguimento de 2 anos, o paciente permaneceu fora da diálise com doença renal crônica avançada (DRC) (estágio IIIb). O paciente de 87 anos apresentava IRA grave com creatinina sérica em 10,41 mg/dL (valor basal de = 2,27 mg/dL). O paciente necessitou de hemodiálise e foi tratado com esteroides, rituximabe e plasmaferese. Infelizmente, o paciente desenvolveu bacteremia induzida por cateter e, posteriormente, evoluiu a óbito por sepse. A hidralazina pode causar IRA grave, resultando em DRC ou óbito. Dado este perfil de eventos adversos extremamente desfavorável e a disponibilidade generalizada de agentes anti-hipertensivos alternativos, o uso de hidralazina deve ser considerado com muita parcimônia.

Immune vasculitis induced atherosclerosis / 华中科技大学学报（医学）（英德文版）

The relationship between immune vasculitis and atherosclerosis was studied. The experimental model of weanling rabbits for immune vasculitis was reproduced by intravenous injection of 10% bovine serum albumin. There were 6 groups: group A, 25 weanling rabbits with immune vasculitis subject to coronary arteriography; group B, 10 normal mature rabbits subject to coronary arteriography; group C, 10 weanling rabbits subject to coronary arteriography; group D, 8 weanling rabbits with vasculitis and cholesterol diet; group E, 8 weanling rabbits receiving single cholesterol diet; group F: 8 weanling rabbits receiving basic diet. Four weeks later, coronary arteriography was performed in groups A, B and C. The rabbits in groups D, E and F were sacrificed for the study of pathological changes in the coronary artery after 12 weeks. The results showed that the dilatation of coronary artery occurred in 6 rabbits of group A, but in groups B and C, no dilatation of coronary artery appeared. In comparison with group E, more severe atherosclerosis occurred in group D, showing the thickened plaque, fibrous sclerosis and atherosclerotic lesion. Percentage of plaques covering aortic intima, incidence of atherosclerosis of small coronary arteries and degree of stenosis of coronary arteries were significantly higher in group D than in group E (P < 0.01). No atherosclerosis changes were found in group F. It was concluded that in the acute phase, the serum immune vasculitis can induce the dilatation of coronary artery of some weanling rabbits, and aggravate the formation of atherosclerosis in rabbits fed with cholesterol diet. Immune vasculitis is a new risk factor of atherosclerosis and ischemic heart disease.