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.

Hydralazine-associated adverse events: a report of two cases of hydralazine-induced ANCA vasculitis.

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.

Systemic inflammation, intestine, and paraoxonase-1.

Serum paraoxonase 1 (PON1) has been shown to act as an important guardian against cellular damage from oxidized lipids in low-density lipoprotein (LDL), plasma membrane, against toxic agents such as pesticide residues including organophosphates and against bacterial endotoxin. PON1 associated with circulating high-density lipoprotein (HDL) has the ability to prevent the generation of pro inflammatory oxidized phospholipids by reactive oxygen species. The activities of the HDL-associated PON1 and several other anti-inflammatory factors in HDL are in turn negatively regulated by these oxidized lipids. In rabbits, mice, and humans there appears to be an increase in the formation of these oxidized lipids during the acute phase response. This results in the association of acute phase proteins with HDL and inhibition of the HDL-associated PON1 that renders HDL pro inflammatory.In populations, low serum HDL-cholesterol is a risk factor for atherosclerosis and efforts are directed toward therapies to improve the quality and the relative concentrations of LDL and HDL. Apolipoprotein A-I (apoA-I) has been shown to reduce atherosclerotic lesions in laboratory animals. ApoA-I, however, is a large protein that is costly and needs to be administered parenterally. Our group has developed apoA-I mimetic peptides that are much smaller than apoA-I (18 amino acids long vs 243 in ApoA-I itself). These HDL mimetic peptides are much more effective in removing the oxidized phospholipids and other oxidized lipids. They improve LDL and HDL composition and function and reduce lesion formation in animal models of atherogenesis. Following is a brief description of some of the HDL mimetic peptides that can improve HDL and the effect of the peptide on PON1 activity.

Inflammation, high density lipoprotein and endothelium.

High density lipoprotein (HDL) has two important roles: a) it modulates inflammation, and, b) it promotes reverse cholesterol transport. HDL-cholesterol levels are inversely correlated with the risk of cardiovascular events. The main component of HDL, apolipoprotein A-I (apo A-I), is largely responsible for reverse cholesterol transport through the macrophage ATP-binding cassette transporter ABCA1. Apo A-I can be damaged by oxidative mechanisms, which render the protein less able to promote cholesterol efflux. HDL also contains a number of other proteins that are affected by the oxidative environment of the acute-phase response. Modification of the protein components of HDL can convert it from an anti-inflammatory to a pro inflammatory and dysfunctional particle. Small peptides that mimic some of the properties of apo A-I have been shown in preclinical models to improve HDL function and reduce atherosclerosis without altering HDL-cholesterol levels. Endothelium is the interface between the blood and the extra vascular environment regulating the traffic of vital molecules between the blood and tissues. Oxidative stress and excess levels of reactive oxygen species disrupt the normal function of endothelium. HDL and other antioxidant/anti-inflammatory systems prevent endothelial dysfunction and maintain the critical balance needed for normal vascular function.