title: Clinically-irrelevant positivity for serum proteinase 3-ANCA in HIV disease.
abstract: Diagnosis of small-vessel vasculitides (granulomatosis with polyangiitis, microscopic polyangiitis, Churg-Strauss syndrome, and their localized forms) is aided by the detection of serum antineutrophil cytoplasmic antibodies (ANCA). However, serum ANCA positivity does not always mean vasculitis. Here, we report on a 61-year-old female patient with very high serum levels of proteinase 3 ANCA, marked hypergammaglobulinemia, low complement levels, and a 16-mm lung nodule on chest CT scan, who was referred to our Institution with a provisional diagnosis of possible granulomatosis with polyangiitis. On admission, history-taking disclosed two recent episodes of viral reactivation (namely, cytomegalovirus and Varicella-Zoster virus), while physical examination revealed lingual and nail involvement suggestive of Candida infection. An immunodeficiency disorder was eventually suspected. Search for antibodies against human immunodeficiency virus (HIV) 1 and 2 turned positive. Western blot analysis confirmed HIV infection. Thus, although ANCA detection may be helpful in diagnosing small-vessel vasculitis in the appropriate clinical scenario, screening for HIV infection should sometimes be considered to discriminate clinically irrelevant serum ANCA positivity.
authors.affiliation: Division of Internal Medicine, Allergy and Clinical Immunology, Polyclinic Hospital of the Second University of Naples, Naples, Italy, and Department of Medical and Surgical Sciences, Second University of Naples, Naples, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Romano
authors.affiliation: Academic Unit of Internal Medicine at Marcianise Hospital, Marcianise, Italy, and Department of Medical and Surgical Sciences, Second University of Naples, Naples, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Sellitto
authors.affiliation: Academic Unit of Internal Medicine at Marcianise Hospital, Marcianise, Italy, and Department of Medical and Surgical Sciences, Second University of Naples, Naples, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Restivo
authors.affiliation: Academic Unit of Internal Medicine at Marcianise Hospital, Marcianise, Italy, and Department of Medical and Surgical Sciences, Second University of Naples, Naples, Italy.
authors.forename: L E
authors.initials: LE
authors.lastname: Adinolfi
mesh_terms: D019268:Antibodies, Antineutrophil Cytoplasmic / Q000097:blood*; D005260:Female; D015658:HIV Infections / Q000276:immunology*; D006801:Humans; D008875:Middle Aged; D053146:Myeloblastin / Q000276:immunology*
chemical_list: D019268:Antibodies, Antineutrophil Cytoplasmic; D053146:Myeloblastin