Discussion
Lemierre’s syndrome (LS) is a rare complication of infections of the
head and neck, with a reported incidence of one case per million people
per year.1 Once common during the “pre-antibiotic
era”, LS had decreased in incidence for decades but has been increasing
in incidence since the 1990s. This is thought to be secondary to better
antimicrobial stewardship and decreased use of antimicrobial therapy for
individuals presenting with pharyngitis.1 Disease is
attributed to infections of the palatine tonsils and peritonsillar
tissue in 87% of cases and infections of the pharynx, parotid glands,
sinuses, mastoids, middle ears, and teeth/gums in the remaining 13% of
cases.2 Males and females are thought to be equally
affected.3 LS has been reported in individuals aged 2
months to 78 years although it is most commonly reported among
previously healthy adolescents and young adults.2,3
Lemierre’s syndrome is thought to originate with primary infection in
the head or neck.4 This is followed by local spread of
the infection through the soft tissues of the neck resulting in
thrombophlebitis of the internal jugular vein. Finally, dissemination of
infection through septic emboli occurs. Sites of infection include the
lungs in up to 80% of cases and bones and joints in up to 27% of
cases.1-4 Additional sites of infection include
cardiovascular structures, skin and muscles, central nervous system,
abdominal organs including liver and spleen, and kidneys. Pulmonary
involvement has included septic emboli, abscess formation, necrotizing
pneumonia, empyema, pneumothorax, pulmonary embolism, and acute
respiratory distress syndrome. LS is most often caused byFusobacterium necrophorum , part of the normal flora of the
pharynx, which may account for up to 85% of cases. Other causes include
additional Fusobacterium species, anaerobes includingBacteroides , Peptococcus , and Peptostreptococcusspecies, and aerobes including Streptococcus , andStaphylococcus species, and others. Polymicrobial infections have
been reported in up to 30% of cases.2 Significant
morbidity has been reported as a result of delayed diagnosis. Mortality
rates have previously been reported as 4-18%; however, more recent
reviews suggest a lower rate.3,5
Individuals with LS often present 4 to 12 days after the initiating oral
pharyngeal infection, which may have resolved by the time of
presentation. Symptoms include high fever (up to 80% of cases),
gastrointestinal complaints (50%), pharyngitis with cervical adenopathy
or neck pain/swelling, myalgia/arthralgia, rigors, and respiratory
symptoms, which may include cough or dyspnea.1,2,5Additional symptoms may be secondary to organ system dysfunction caused
by septic emboli. Diagnosis is often made based on Doppler ultrasound or
computed tomography imaging of the head and neck or the growth ofFusobacterium or other bacteria from blood or abscess cultures.
Therapy for LS typically involves long term, intravenous antibiotic
therapy, surgical drainage of abscess sites, and
anticoagulation.1-6 Metronidazole is often reported as
standard therapy for LS. Other antibiotic considerations include
carbapenems or penicillin/beta-lactamase inhibitor combinations, which
may provide broader coverage for polymicrobial infections. Duration of
therapy is often 4 to 6 weeks to allow for adequate penetration of
thrombi as well as treatment of secondary problems such as
osteomyelitis. The role of anticoagulation therapy is more
controversial. Some data suggest that the use of anticoagulation hastens
overall response while others indicate adequate clinical response
without additional therapy.
Lemierre’s syndrome is a rare disorder of the head and neck that may be
associated with significant morbidity and mortality if diagnosis and
treatment are delayed. Hence, a high index of suspicion must be
maintained in order to identify children with LS. Pediatric
pulmonologists will most likely encounter LS in patients hospitalized
with prolonged fever and multiple septic pulmonary emboli. LS must be
considered as part of the differential diagnosis for any child with
multiple cavitary nodules identified on chest CT imaging. This is
particularly true if there is a history of proceeding oral pharyngeal
infection or acute signs and symptoms suggesting pathology in the head
and neck. The growth of Fusobacterium species from blood culture
or abscesses should also suggest the possibility of LS. If LS is
suspected, Doppler ultrasound examination of the neck and possible CT
imaging of the head and neck should be obtained. Therapy should include
long-term intravenous antibiotics directed at the treatment of specific
organisms recovered. Adjuvant therapy with surgical incision and
drainage of abscesses or anticoagulation therapy may be necessary in
some cases.