68 year old male presented with sudden onset of fever, chills, left neck pain, left arm pain and dysphagia to solids and liquids. The pain was described as stabbing and radiated to the upper chest and back. Vital signs were remarkable for a fever of 102.7o F and a heart rate of 120 beats per minute. He was non-toxic appearing and demonstrated a warm fluctuant mass on left neck. Lab data revealed a white blood cell count of 17,000/mL with neutrophilic predominance. A CT scan of the chest, abdomen and pelvis with contrast revealed extensive phlegmonous changes of left chest wall, left cervical region, and superior mediastinum and abscess in left thyroid lobe. FNA drainage yielded purulent material, but no bacterial growth from the culture. ENT performed an incision and drainage procedure and culture grew Streptococcus intermedius. Initial blood cultures grew Streptococcus constellatus. Endocarditis was ruled out and dental consultation revealed no obvious oral source. The bacteremia was successfully treated with Ertapenem for one month duration.
Discussion:
Three isolates including Streptococcus constellatus, Streptococcus anginosus, and Streptococcus intermedius are part of the Streptococcus milleri group which is a member of the viridans group of streptococci. All three organisms are normal commensal organisms of the oropharyngeal and gastrointestinal flora; however, they have been implicated in causation of abscesses involving the orofacial and sinus area, respiratory tract, and abdominal cavity. Several case reports have called to attention septic shock leading to mortality from bacteremia from these organisms. The virulence factors for each of these microbes have not been clearly elucidated but include a polysaccharide capsule that inhibits phagocytosis which often leads to development of rapid suppurative infections. The most severe complications involve airway obstruction and central nervous system involvement. Our case presents a patient who had bacteremia from Streptococcus constellatus which is an uncommon cause of bloodborne pathogen. This bacteria is typically implicated in superficial head and neck abscesses and the close proximity to central nervous system warrants early recognition and treatment. What is more impressing is that the culture from the abscess was consistent with Streptococcus intermedius but it was Streptococcus constellatus isolated in bloodstream. It is not uncommon for this presentation as many of these streptococcus species will often have synergistic relationship, even with anaerobes, in forming abscesses. Treatment is based on debridement and drainage when appropriate and use of beta-lactam antibiotics, particularly ceftriaxone as it has excellent tissue penetration and infrequent dosing. We chose ertapenem because of concern for co-infection with anaerobes in abscess formation.
Conclusions:
Hospitalists are often the first line physicians confronted with the management of sepsis. It is imperative to know that bacteremia by any one of the streptococcus milleri group warrants imaging for evaluation of abscess, particularly, those involving the head and neck region which carries a higher risk of invasion to the central nervous system and mortality.