Discussion
Alagille syndrome was first described by Daniel Alagille in 1969.The
incidence of Alagille syndrome has been reported as 1:30000 live births
(1). Various mutations in JAG1 and NOTCH2 genes have been observed in
this syndrome(2-3). These genes encode transmembrane ligands and
receptors involved in the Notch signaling pathway. Intracellular
proteins formed after proteolytic events in the Notch signaling pathway
control gene transcription in the cell nucleus(4). The diagnosis of
Alagille syndrome can be made clinically or by demonstrating JAG1 and
NOTCH2 gene mutations.
The most common cardiovascular abnormalities seen in Alagille syndrome
are stenosis or hypoplasia of the pulmonary artery branches. Another
frequently observed condition is tetralogy of Fallot. Apart from these
pathologies, various anomalies such as atrial and ventricular septal
defect, bicuspid aorta and valvular aortic stenosis may also be seen (5)
and observation of cardiac involvement in patients with Alagille
syndrome significantly increases mortality (6). Although there is no
study conducted for the relationship between Alagille syndrome and
pulmonary hypertension; the presence of pulmonary hypertension in these
population is described in several case reports. According to literature
it is seen that pulmonary hypertension generally develops in the setting
of pulmonary stenosis in patients with Alagille syndrome (7-8). However,
recent studies have shown that pulmonary hypertension may develop as a
result of disorders in the Notch gene pathway (9-11). Presence of NOTCH
mutation seen in our patient may have contributed to the development of
group 1 pulmonary hypertension without cardiac anomaly.
Infective endocarditis diagnosis is made by the modified Duke criteria
(12). The main topics of treatment can be summarized as antibiotic
therapy and surgical treatment in people with appropriate indications.
Particularly,indications for surgery in people with a diagnosis of
infective endocarditis can be classified into three main groups ;
development of heart failure, prevention of uncontrollable infections
and embolisms. Emergent valve surgery is recommended with a class 1
indication in cases of acute severe mitral or aortic regurgitation and
associated refractory pulmonary edema/cardiogenic shock in infective
endocarditis cases. Cardiac surgery is urgently recommended for patients
with severe aortic and mitral valve regurgitation and in the presence of
signs of heart failure or echocardiographic findings showing poor
hemodynamic tolerance (13).