Presencia de ADN bacteriano en el tejido valvular de pacientes con cardiopatía reumática crónica / Presence of bacterial DNA in valvular tissue of patients with rheumatic heart disease

Background: Rheumatic heart disease (RHD) is a delayed consequence of a pharyngeal infection with Group A streptococcus (GAS), usually ascribed to a cross-reactive immune response to the host cardiac tissues. Acute rheumatic fever (ARF) and its ensuing valvular sequelae are thus considered the prototype of a post-infectious autoimmune disease, with no direct evidence of residual streptococcal antigen in diseased valvular tissues. However, recent studies concerning the antigenic specificity and clonality of intralesional lymphocytes have revealed oligoclonal expansions characteristic of an antigen specific response, that might be related to GAS. Aim: To search for bacterial DNA in valvular tissue from RHD patients and controls. Material and methods: We extracted DNA from surgically excised valve specimens from 15 RHD patients and 6 non RHD controls and tested for the presence of bacterial DNA by Polymerase Chain Reaction (PCR) with primers for 16S rRNA. Results: Eighty percent (12/15) of valve specimens from RHD patients were positive for bacterial DNA, as opposed to none of the valves (n =6) from non RHD controls. Conclusions: These results suggest that GAS might persist in valvular tissue in patients with ARF and contribute to the inflammatory scarring lesion that leads to cardiovascular sequelae.

Síndrome de vasculitis renal y pulmonar con anticuerpos anticitoplasma de neutrófilos y anticuerpos antimembrana basal positivos: informe de un caso / The syndrome of renal and pulmonary vasculitis with positive neutrophil anticytoplasmic antibodies and antibasement membrane antibodies: a case report

The authors present a case of Goodpasture's syndrome with necrotizing vasculitis of spleen and appendix. Serological examination shows antiglomerular basement membrane antibodies and antineutrophil cytoplasmic antibodies. The authors review the literature to establish if this or other similar cases can be considered a distinct disease entity. The authors also mention the laboratory methods that are currently being used to classify more precisely the vasculitides associated with glomerulonephritis