Discussion
Infective endocarditis is not a disease of high incidence, but when it
occurs, it can lead to several complications and even death, requiring
prompt diagnosis and appropriate treatment.
In recent years, infective endocarditis associated with atopic
dermatitis has been reported. Nakatani et al. reported that of 513 cases
of infective endocarditis, 322 had some background factors, including
atopic dermatitis in 5 cases.3 Fukunaga et al.
reported 120 cases of infective endocarditis, of which, 8 were
associated with atopic dermatitis (6.7%).4 In atopic
dermatitis, the production of IL-4, IL-10, IL-13, etc. is high,
suppressing the production of antibacterial peptides such as β-defensin
and cathelicidin, which are related to skin defense,1and therefore rendering the skin susceptible to infection withStaphylococcus aureus . Consequently, Staphylococcus aureusis detected in more than 90% of patients with atopic
dermatitis.2 Skin breakage due to scratching may allow
bacterial invasion, resulting in bacteremia and infective endocarditis.
Infective endocarditis with a background of atopic dermatitis is common
in young patients, and the most common causative organism is MSSA. It is
also characterized by a high rate of embolism.5 These
findings were observed in the present case.
Although there have been reports of cases of infective endocarditis
caused by atopic dermatitis that did not require surgery and were
relieved by antibiotics,6 and there is a report of a
patient who used dupilumab to improve atopic dermatitis and then
underwent standby surgery with good results,7 because
cerebral infarction due to infective endocarditis is fatal, early
surgical intervention is necessary when there is a high likelihood of
recurrent embolization due to verrucous disease. Some reports suggest
that early surgery for infective endocarditis is associated with early
death, recurrent infective endocarditis, and valve
dysfunction8; contrarily, other reports suggest that
early surgery is useful for large verrucae.9 Infective
endocarditis, especially when associated with atopic dermatitis, has
been reported to have a high rate of embolism, and early surgery should
always be kept in mind. Even right-sided infective endocarditis, which
is considered sensitive to antibiotic therapy, may cause embolization or
exacerbation of sepsis during treatment if atopic dermatitis is present
in the background.10,11 In the present case, the
patient had a mobile 10-mm verruca with a high likelihood of repeated
embolization, prompting the policy of urgent surgery.
Additionally, the most common approach for surgical treatment of
infective endocarditis is median sternotomy; however, there is a high
possibility of postoperative mediastinitis with a median sternotomy, and
some reports recommend a right thoracotomy.12 Although
reliable verrucous resection and treatment of valvular disease are the
highest priorities, a right small thoracotomy should be considered. In
our case, we performed MICS and were able to avoid mediastinitis; the
patient improved without wound infection.
Vancomycin and ceftriaxone were used for postoperative antibiotic
therapy. The antibacterial activity of vancomycin and ceftriaxone
against Staphylococcus aureus has been reported to be inferior to
cefazolin13; however, given the multiple cerebral
emboli, we chose ceftriaxone due to its good cerebrospinal fluid
transfer.14 Close observation and skin treatment
should be continued; moreover, the patient should be treated for atopic
dermatitis in collaboration with a dermatologist.