FROM "Endocarditis"
(I edited this before you originally graded it, and changed things based on the comments made.11/12/16)
It started out in the 1920's affecting young adults under the age of 34, although it is not commonly seen in young children; now the age has gone up considerably to 58 years. One type of infective endocarditis (IVDA IE) however, has an average age that stayed 30 years. This is often overlooked in patients of this age because many of them presented with much subtler symptoms than younger patients in the 1920's. [1]
Since the valves of the heart do not receive any dedicated blood supply, defensive immune mechanisms (such as white blood cells) cannot directly reach the valves via the bloodstream. If an organism (such as bacteria) attaches to a valve surface and forms a vegetation, the host immune response is blunted. The vegetations look like small white masses that can show up on an echocardiogram.[2] The lack of blood supply to the valves also has implications on treatment, since drugs also have difficulty reaching the infected valve. Another sign to look for would be a change in an existing heart murmur. This can also contribute to failure of ventricles and arteries.[3]
Normally, blood flows smoothly past these valves. If they have been damaged (from rheumatic fever, for example) the risk of bacteria attachment is increased.[2]
Rheumatic fever is common worldwide and responsible for many cases of damaged heart valves. Chronic rheumatic heart disease is characterized by repeated inflammation with fibrinous resolution. The cardinal anatomic changes of the valve include leaflet thickening, commissural fusion, and shortening and thickening of the tendinous cords.[3] The recurrence of rheumatic fever is relatively common in the absence of maintenance of low dose antibiotics, especially during the first three to five years after the first episode. Heart complications may be long-term and severe, particularly if valves are involved. While rheumatic fever since the advent of routine penicillin administration for Strep throat has become less common in developed countries, in the older generation and in much of the less-developed world, valvular disease (including mitral valve prolapse, reinfection in the form of valvular endocarditis, and valve rupture) from undertreated rheumatic fever continues to be a problem.[4]
In an Indian hospital between 2004 and 2005, 4 of 24 endocarditis patients failed to demonstrate classic vegetation. All had rheumatic heart disease and presented with prolonged fever. All had severe eccentric mitral regurgitation. (One had severe aortic regurgitation also.) One had flail posterior mitral leaflet.[5]
- ^ Brusch, John L. (2007-03-13). Infective Endocarditis: Management in the Era of Intravascular Devices. CRC Press. ISBN 9781420019834.
- ^ Cabell, Christopher H.; Abrutyn, Elias; Karchmer, Adolf W. (2003-05-27). "Bacterial Endocarditis". Circulation. 107 (20): e185–e187. doi:10.1161/01.CIR.0000071082.36561.F1. ISSN 0009-7322. PMID 12777321.
- ^ Ashley, Euan A.; Niebauer, Josef (2004-01-01). Infective endocarditis. Remedica.