postanginal septicaemia in the early 20 century ; originally associated with a mortality reaching 90% it involves a classic triad of oropahryngeal sepsis , internal jugular vein ( ijv ) thrombophlebitis and metastatic abscess formation ( 1 ) . 
clinical findings can therefore vary considerably from neck pain and swelling associated with thrombophlebitis to pleuritic chest pain , haemoptysis , dyspnoea or arthralgia as a result of septic thromboemboli .
we report a case of predominantly external jugular vein ( ejv ) involvement in an adolescent male with negative blood culture results .
a twelve year old boy presented to the children s assessment unit with a 24 hour history of unilateral face and neck swelling on a background of seven days progressive sore throat and dysphagia .
minor systemic upset was also noted including headache , vomiting and non specific abdominal pain .
a provisional diagnosis of tonsillitis had been made five days earlier by the local gp and a course of erythromycin and penicillinv commenced .
examination revealed tender swellings over the left temporal area , angle of the mandible and upper third of the sternocleidomastoid extending into the submandibular region .
examination of the oral cavity was complicated by trismus , however no obvious tonsillar enlargement , erythema or exudate was recorded .
initial blood results showed an elevated c - reactive protein of 155mg / l and white cell count of 16.6(10 * 9l ) .
initial imaging of the neck comprised an ultrasound scan ; this demonstrated normal right sided vasculature but abnormal left ejv and retromandibular veins .
these veins appeared dilated with increased wall vascularity and showed no recordable signal on doppler imaging , an appearance in keeping with an inflammatory thrombophlebitis . to note
an mri brain with venography ( mrv ) sequences provided greater anatomical delineation ( figure 1 ) . despite a coincidental finding of a smaller calibre left venous sinus ; thrombus was not seen to extend intracranially .
lastly an echocardiogram was sought confirming a normal heart with no septal defects , vegetations or thrombus .
mrv brain images demonstrate bilateral sagittal , straight , transverse and sigmoid sinuses with no evidence of thrombus extension . both right and left ijv as well as right ejv are clearly patent . the left ejv could not be demonstrated .
treatment was started promptly on clinical suspicion of ls and consisted of intravenous ( iv ) metronidazole , benzyl penicillin and dexamethasone ; anticoagulation was not given .
the patient remained in hospital on iv antibiotics for a total of 14 days , the noted swellings slowly decreased in size , blood results normalized and the trismus resolved .
he remained afebrile throughout , developed no subsequent complications and was discharged home to complete seven weeks of oral antibiotics .
despite ijv thrombophlebitis forming a main diagnostic criterion for ls , we report a case in which the primary vascular involvement is that of the ejv , with a corresponding normal ijv .
studies have previously described ls with thrombosis of the carotid artery , intracranial venous sinus and abdominopelvic vessels ( 1 ) ; only three have ever described involvement of the ejv .
this unusual finding helps to highlight the variable nature of this condition and the diagnostic confusion it may herald . to note there are reported cases of ls in which there was no demonstrable vascular involvement .
numerous theories have tried to explain the spread of organisms from oropharynx to the surrounding vein ; haematogenous via the tonsillar vein , secondary to lymphangitis or via direct spread through deep neck spaces .
( 3 ) the incidence of ls within developed countries is now thought to lie around one per million per year , significantly reduced from the pre antibiotic era , however a resurgence over the last decade has recently been proposed .
mortality has been recorded at 6.9% however morbidity and complications remain high as the early diagnosis can often be missed and treatment delayed .
( 3 ) although classically described as following an oropharyngeal infection ls has been reported developing from other primary infective sites including the middle ear , sinuses , mastoid and teeth ( 1 ) .
the development of sepsis in ls is often delayed , presenting three to seven days from signs of the primary infection , which may have all but resolved ( 4 ) , making accurate history taking and a high index of clinical suspicion ever more important .
ls is classically but not exclusively associated with an obligate oropharyngeal gram negative bacillus ; fusobacterium necrophorum .
other causative pathogens described in the literature include streptococcus , staphylococci and bacteroides species ( 5 ) .
it has however been reported that in almost 13% of cases no pathogen is isolated on culture ( 6 ) .
ls can also be associated with thrombophillia ( thought to be endotoxin induced ) ( 5 ) .
the role of anticoagulation however remains controversial with no conclusive literature evidence ; the decision should therefore be made on clinical grounds ; assessing severity of symptoms , poor treatment response and degree of thrombus extension .
a recent history of a sore throat in conjunction with sepsis and or a suggestive and often declining clinical picture should always prompt early antibiotic therapy whilst a diagnosis of ls is sought ; hopefully preventing the development of late embolic complications .
differential diagnoses to consider include infectious mononucleosis , parapharyngeal abscess , lymphoma , pneumonia ( including atypical forms ) and other embolic sources ( e.g. infective endocarditis ) .
 oropharyngeal infections are routinely encountered within general practice and accident and emergency departments . 
 most settle with simple analgesia and antibiotics ; occasionally such patients may develop lemierre s syndrome ( ls ) a rare and potentially fatal sequela that can be easily overlooked . 
 we aim to highlight the main symptoms , pathology , investigations and management . 
INTRODUCTION
CASE REPORT
DISCUSSION