Glomerular Lesions of Subacute Bacterial Endocarditis

Abstract

1. In most cases of chronic or subacute bacterial endocarditis due to the endocarditis coccus (Streptococcus viridans), there exists a distinctive pathological lesion in some of the glomeruli due to bacterial emboli. 2. The salient features of the pathological picture are first, the involvement of one or more loops of a variable number of glomeruli; secondly, the absence of any visible disease in the uninvolved glomeruli and in the uninvolved portions of affected glomeruli; and thirdly, the association in most of the bacterial cases of all the various stages of the glomerular process often seen in a single microscopical section. 3. The lesion does not occur in cases of acute endocarditis, and up to the present time it has been absent in cases of subacute bacterial endocarditis due to organisms other than the endocarditis coccus. 4. In a group of cases having vegetations that are typical of those in the active stage of subacute endocarditis (except that they are free from bacteria and healing or healed), the healed stage of this distinctive glomerular lesion is present, although it is less extensive than in the active bacterial cases. 5. These cases, therefore, are most probably examples of subacute bacterial endocarditis due originally to the endocarditis coccus, but in which the endocardial vegetations have become free from bacteria rather early in their course and are now healing or healed, as claimed by Harbitz and Libman. 6. During the active bacterial stage of the disease, if the glomerular lesions are not too numerous, the only symptoms produced will be an almost constant hematuria, usually demonstrable only microscopically. If the glomerular lesions are very numerous, symptoms resembling those of subacute hemorrhagic nephritis may occur and may even cause a fatal issue. If the glomerular lesions are very numerous but not sufficient to cause death, and the cardiac lesion should go on to healing, a contracted kidney, secondary to the glomerular lesion, may subsequently ensue and produce the typical symptoms and death. In such a case, the finding of the healed or healing lesion of subacute bacterial endocarditis will be accidental.

Infective endoarditis: a history of the development of its undestanding

“…15 He used the term “fungus” to describe “wart-like excrescences” occurring in an 18-year-old patient who also had abscess formation at the aortic root. This report was also the first to document peripheral embolization, later described in greater detail almost a century later by Löhlein and Baehr 16 , 17…”

Rapidly Progressive Glomerulonephritis Associated with Bacterial Endocarditis: Efficacy of Antibiotic Therapy Alone

“…'Focal embolic nonsuppurative glomerulonephritis' [2] is the most typical renal lesion complicating bacterial endocarditis. It corresponds to a focal and segmental pro liferative glomerular lesion [5], Earlier investigators [2,11] thought nephritis resulted primarily from emboli aris ing from infected valves.…”

“…It corresponds to a focal and segmental pro liferative glomerular lesion [5], Earlier investigators [2,11] thought nephritis resulted primarily from emboli aris ing from infected valves. However, another paper [4] reported that there was no evidence to implicate emboli of bacterial vegetations in the pathogenesis [4], Other types of nephritis have been described: diffuse proliferative GN predominates in bacterial endocarditis whatever the cau sative organ ism [12] whether with or without extracapilla ry proliferation [5],…”

“…Bacterial infective glomerulonephritis (GN) associated with bacterial endocarditis has been recognized since the early part of the century [1,2]. Clinical or morphologic evidence of renal involvement has been described with an incidence ranging from 2 to 60%.…”

Renal Complications of Bacterial Endocarditis

“…This led him to suggest that septic emboli account for the glomerular lesions which he termed 'embolic nonsup purative focal nephritis'. Two years later, Baehr [14] reported the same lesions in 21 of 25 cases of bacterial endocarditis, in 5 of which he noted bacterial emboli and in 2 a diffuse glomerulonephritis. In a subsequent report [ 15] of 9 patients with bacterial endocarditis who died of uremia, diffuse glomerulonephritis was noted to be present in all 9 cases and characterized as acute in 2 and chronic in 7 of them.…”