The University of Toledo Translation Journal of Medical Sciences 
Pulmonology Abstract, Department of Medicine Research Symposium UTJMS 2023 May 5; 11(1):e1-e1 

https://dx.doi.org/10.46570/utjms.vol11-2023-772 

Streptococcus intermedius - An Uncommon 
Cause of Severe Pulmonary Infections in 
Immunocompetent Patients 
A. Al-Tkrit, MD1*, Y. Yoon, MD1 

1Division of Pulmonology and Critical Care Medicine, Department of Medicine, The 
University of Toledo, Toledo, OH 43614 

*Corresponding author: Amna.Al-Tkrit@utoledo.edu

Published: 05 May 2023 

Streptococcus intermedius is a Gram-positive, facultative anaerobe that is considered a rare cause of 
severe pulmonary infections in immunocompetent patients.  

• Case1: A 69-year-old woman with PMHx of T2DM, and chronic dysphagia presented with
worsening shortness of breath for one-week, high WBC, and CT chest showed left large,
loculated pleural effusion with LLL consolidation.

• Case2: A 51-year-old woman with PMHx ADHD, depression, anxiety, and RA presented with
pleuritic right-sided chest pain for 2 days, hypotension, tachycardia, high WBC, CT chest of the
showed large right sided loculated hydropneumothorax with multiple consolidative opacities in
right lung.

For both cases pleural fluid analysis was consistent with empyema, culture was positive for 
Streptococcus intermedius. Chest tubes were placed. Both patients responded to a combination of 
medical and surgical treatment and were discharged from the hospital in a stable condition. 

Discussion: Streptococcus intermedius is commonly identified in abscesses of brain or liver. However, 
it is important causative agent of severe respiratory infections, including necrotizing pneumonia, lung 
abscesses, and empyema. S.intermedius is the causative of about 13-44% of pulmonary abscesses and/or 
cases of empyema, and accounts for around 2-5% of cases of bacterial pneumonia. Aspiration of oral 
secretion is the main risk factor. S. intermedius is generally susceptible to beta-lactam agents, including 
penicillins and cephalosporins, though some cases of resistance have been reported. In patients who are 
allergic or resistant to beta-lactam antibiotics, vancomycin may be considered an appropriate alternative. 
The duration of antibiotic therapy may vary from 2 to 4 weeks. 

https://dx.doi.org/10.46570/utjms.vol11-2023-772
mailto:Amna.Al-Tkrit@utoledo.edu