Innocent victim of a localised outbreak: legionella endocarditis

Abstract

Legionella pneumophila endocarditis is extremely rare. The case of a fit 26 year old man who had previously undergone homograft aortic root replacement is reported. He was admitted with legionella pneumonia during the recent localised outbreak but went on to develop endocarditis. His aortic valve was replaced with a mechanical valve and he made an uneventful recovery. Public health issues and diagnosis in susceptible patients during localised outbreaks are discussed.A 26 year old man was admitted to his local hospital with a microbiologically confirmed diagnosis of Legionella pneumophila pneumonia contracted during an outbreak in Cumbria. Significant medical history included congenital ventricular septal defect with aortic valve prolapse. Previous surgical procedures included closure of the ventricular septal defect and repair of the prolapsing aortic cusp in 1986. This was followed by aortic root replacement with a homograft for worsening aortic regurgitation in 1994. He was asymptomatic until recently and his most recent echocardiogram did not show any aortic regurgitation.Soon after his admission with legionella pneumonia, he required admission to an intensive therapy unit for respiratory failure requiring ventilation, where his stay was further complicated by the development of severe aortic regurgitation, disseminated intravascular coagulation, and microemboli affecting his digits. A diagnosis of legionella endocarditis was established and he was treated with intravenous clarithromycin and rifampicin. He made a good recovery. He was referred for urgent repeat aortic valve replacement. An echocardiogram showed severe aortic regurgitation with a dilated left ventricle (left ventricular end systolic diameter 7.0 cm) and near equilibrium of the aortic and left ventricle pressure at the end of diastole.He underwent repeat aortic valve replacement. Intraoperatively, complete destruction of both left and right cusps of the aortic valve were noted. However, there was no evidence of active infection or aortic root involvement. The valve leaflets were excised and the valve was replaced with a 23 mm St Jude Medical (St Paul, Minnesota, USA) mechanical valve. The cultures of the excised leaflets were negative, which is consistent with a prolonged course of antibiotics. He made an uneventful postoperative recovery. An echocardiogram before discharge showed no aortic regurgitation.

Legionella native valve endocarditis case report and review of literature

“…Embolic events due to Legionella endocarditis seem to be very rare and have been reported in only two other cases with valve-prosthesis infection [10,11]. Our patient showed two fresh spleen infarctions diagnosed in thoraco-abdominal CT scan.…”

A case of malignant melanoma patient complicating pneumonia of Legionella pneumophila Sg 1 infection and means to detect Legionella from the patient

“…In an immunocompetent patient, community-acquired pneumonia is caused by L. longbeachae (Diederen et al, 2005). Numerous cases have been reported related to L. pneumophila and non-L. pneumophila infection around the world, such as perimyocarditis (Burke et al, 2009), community-acquired lung abscess (Girard and Gregson, 2007), legionella endocarditis (Massey et al, 2003), rheumatoid arthritis (Chang et al, 2001), chronic lymphocytic leukemia (Hendrick, 2001;Siegel et al, 2010;Thacker et al, 1992), Myocarditis (Armengol et al, 1992), cancer (Jacobson et al, 2008) and invasive aspergillosis (Saijo et al, 2008). However, the case of malignant melanoma patients complicating pneumonia of L. pneumophila Sg 1 infection had not been reported before.…”

“…Therefore, many methods for detection of Legionella appear. These methods include urine antigen detection, direct fluorescent antibody (DFA) and sequence-based genotypic classification scheme such as PCR and real-time PCR (Armengol et al, 1992;Cloud et al, 2000;Massey et al, 2003;Thacker et al, 1992). Most commercially available assays based on PCR target species-specific regions within the 16S and 5S rRNA genes as well as in the mip gene.…”

Legionella micdadei, a New Cause of Prosthetic Joint Infection

“…These cases contrast with those of surgical wound infection, in which the microorganism is inoculated directly (3, 7). Legionella has already been reported to be responsible for infection of prosthetic material other than joints (4,8,9,12,13,15). Most patients were immunosuppressed, and the portal of entry remained unknown.…”