We report a case of a severe ear infection in a 35-year-old man treated with ixekizumab for psoriasis. Ixekizumab is a humanized monoclonal antibody that selectively prevents the interaction between interleukin 17 A and its receptor. Biologicals like ixekizumab are used to achieve symptom relief in autoimmune diseases including psoriasis. Unlike the mild upper respiratory tract infections usually described as side-effects of this treatment, we report a case of a patient who presented with a severe otitis media, complicated with a facial paresis and nasopharyngeal abscess. To the best of our knowledge, this is the first case presenting a severe, complicated ear infection as a possible side effect of ixekizumab. We conclude that when using ixekizumab, vigilance for upper airway infections is needed and if necessary, interruption of therapy should be considered. However, further research is needed to confirm this hypothesis.

BACKGROUND: This case series investigated the clinical manifestations, diagnoses, and treatment of cerebral abscesses caused by Streptococcus anginosus. We retrospectively analyzed the clinical characteristics and outcomes of three cases of cerebral abscesses caused by Streptococcus anginosus and conducted a comprehensive review of relevant literature.
METHODS: Case 1 presented with a history of left otitis media and exhibited high fever, confusion, and vomiting as primary symptoms. Postoperative pus culture indicated a brain abscess caused by Streptococcus constellatus infection. Case 2 experienced dizziness for two days as the primary symptom. Postoperative pus culture suggested an intermediate streptococcal brain abscess. Case 3: Enhanced head magnetic resonance imaging (MRI) and diffusion-weighted imaging revealed occupancy of the left temporal lobe, initially suspected to be a metastatic tumor. However, a postoperative pus culture confirmed the presence of a brain abscess caused by Streptococcus anginosus infection. The three cases presented in this case series were all patients with community-acquired brain abscesses resulting from angina caused by Streptococcus group infection. All three patients demonstrated sensitivity to penicillin, ceftriaxone, vancomycin, linezolid, chloramphenicol, and levofloxacin. Successful treatment was achieved through stereotaxic puncture, drainage, and ceftriaxone administration with a six -week course of antibiotics.
CONCLUSIONS: Preoperative enhanced head MRI plays a critical role in distinguishing brain tumors from abscesses. Selecting the correct early diagnostic methods for brain abscesses and providing timely intervention are very important. This case series was in accordance with the CARE guidelines.

Polymicrobial endocarditis is rare but is seen in those with risk factors like diabetes mellitus, structural heart disease, congenital heart defects, prosthetic devices, and intravenous drug use. We report the case of a 30-year-old woman with a past medical history of chronic Hepatitis C and IV drug use who presented with a one-week history of generalized weakness, subjective fevers, lower extremity abscesses, and occasional chest pain. Blood cultures were positive for Streptococcus anginosus, Gemella hemolysans, and Pseudomonas aeruginosa. A transthoracic echocardiogram revealed a very large tricuspid valve vegetation and severe tricuspid regurgitation. Her course was complicated by a complete heart block, septic pulmonary emboli, acute hypoxic respiratory failure, and cardiogenic shock meeting the criteria for early surgical intervention. She underwent an emergency tricuspid valve replacement and pacemaker implantation. During the operation, it became evident that her valve was destroyed with vegetation. A week after the operation, her ejection fraction had improved to 50% and she only exhibited mild tricuspid valve regurgitation. Six weeks later, she was in a stable condition and presented for follow-up. Surgery is necessitated in nearly 50% of Gemella endocarditis cases, 62% of cases with S. anginosus group, and approximately 56% of P. aeruginosa cases. To our knowledge, this is the only case of polymicrobial endocarditis caused by G. hemolysans, S. anginosus, and P. aeruginosa.

A 60-year-old male presented to our institution for abdominal pain and was later admitted to the intensive care unit for shock, acute hypoxemic respiratory failure, and acute kidney injury. He was subsequently found to have a large left-sided pleural effusion with empyema secondary to Streptococcus constellatus. With the emerging threat and growing prevalence of Streptococcus anginosus group pathogens, there is now greater clinical importance in identifying viridans streptococci at the species level. While immunosuppressed individuals are at greater risk of opportunistic pathogens, this case presentation demonstrated that Streptococcus constellatus can remain a serious community-acquired pathogen for the non-immunosuppressed. Continued interprofessional team care management and a greater look into the reasons for greater Streptococcus anginosus pathogenicity may be indicated.

The Streptococcus anginosus group (SAG) is a subgroup of viridans streptococci comprising three species: S. anginosus, S. constellatus, and S. intermedius. SAG usually resides in the oral cavity and colonizes the throat, and the gastrointestinal and genitourinary tracts. SAG can form abscesses in various parts of the body; however, the clinical features of SAG infection are not clear. Here, we reviewed the medical records of all SAG bacteremia patients aged over 18 years who were diagnosed between January 2010 and December 2021 at a tertiary university hospital. We then compared clinical characteristics, source of infection, need for surgical or interventional treatment, and 28-day mortality rates among each species of SAG. Differences in percentages between groups were compared using a proportion test, and differences between mean values were assessed using the Kruskal-Wallis test with post-hoc Bonferroni correction. In total, 84 cases of SAG bacteremia (40 S. anginosus cases, 31 S. constellatus cases, and 13 S. intermedius cases) were identified. The most common comorbidity was diabetes mellitus (n = 26, 31%), and the most common source was hepatobiliary infection (n = 30, 35.7%). Polymicrobial bacteremia was observed in 22.6% (19/84) of cases. Twenty-eight day mortality due to S. anginosus bacteremia was 12.5%; no deaths were reported in the S. constellatus and S. intermedius groups. However, the difference among the groups was not significant (p = 0.054). Hepatobiliary infection was the most common source of SAG bacteremia. In addition, S. anginosus bacteremia resulted in more severe disease and higher mortality rates than S. constellatus or S. intermedius bacteremia.

A 55-year-old female with hypertension presented to our facility with complicated pneumonia. She complained of progressively worsening shortness of breath and pleuritic chest pain. She was in her usual state of health except for an upper respiratory infection treated with oral antibiotics a month prior. At the presentation, she was febrile, tachycardic, and hypoxic on room air. A chest computed tomography (CT) showed near-complete opacification of the right lung, a cavitation with the fluid level in the right middle lobe, and moderate-to-large effusion. Broad-spectrum antibiotics were started. Sputum culture was later positive for methicillin-resistant Staphylococcus aureus, which prompted antibiotic de-escalation to vancomycin. A chest tube was placed into the right pleural space draining 700 mL of exudative fluid, which cultures grew Streptococcus anginosus group (SAG) bacteria. Due to persistent respiratory distress and residual effusion, right thoracotomy and decortication were performed. A right upper lobe abscess ruptured into the pleural space was noted during the procedure. Pathology revealed necrotic tissue, and the microbiological workup was negative. The patient clinically improved postoperatively and was discharged home with oral Linezolid.

Pyogenic liver abscess (PLA) is known as a pus-filled lesion found in the liver which can quickly become fatal if not found and treated in a timely manner. The most common group of bacteria found in PLA is the Streptococcus Anginosus Group (SAG). Patients with PLA usually present with fever and right upper quadrant abdominal pain which can at times be referred to the right shoulder owing to dermatomal involvement. We present a case where a patient with a past medical history significant for recent diverticulosis presenting with a left lower quadrant abdominal pain, fever, and hypotension and on further workup was found to have a PLA. Blood cultures and cultures from the abscess grew Streptococcus constellatus. This bacteria is part of the SAG group however, it is rarely found in PLA and bloodstream.

Brain abscess is a life-threatening illness that occurs when an intracerebral infection leads to cerebritis and subsequent pus formation within a well-vascularized capsule. While streptococci (aerobic, anaerobic, and microaerophilic) are the most common bacteria isolated, its presentation as multifocal brain abscesses is rarely described. In this report, we describe a 43-year-old male patient who presented to the emergency department due to progressive lethargy and low-grade fever of seven days worsening. Upon further evaluation, the patient was found to have multiple brain abscesses secondary to Streptococcus intermedius, confirmed by the culture of stereotactic aspiration of brain collection. This case underlines the importance of considering Streptococcus intermedius as a cause of multifocal brain abscesses.

BACKGROUND: Viridans group streptococci (VGS) are the most common causative organisms of infective endocarditis. Among VGS, the Streptococcus anginosus group (SAG) is often associated with abscess formation, and delayed diagnosis leads to increased morbidity and mortality. This study aims to examine the factors associated with SAG bacteremia and develop a predictive scoring method.
METHODS: This single-center retrospective case-control study of patients with VGS bacteremia compared the background and clinical characteristics between the SAG and non-SAG groups. The univariate analysis used the χ2 test and t-test. The multivariate analysis was conducted using logistic regression.
RESULTS: Out of 161 patients, 95 had SAG and 66 had non-SAG bacteremia. Age >63 years: 2 points (odds ratio [OR] = 3.52, 95% confidence interval [CI]: 1.64-7.54); solid tumor: 2 points (OR = 4.44, 95% CI: 1.42-6.77); C-reactive protein >7.61 mg/dL: 3 points (OR = 5.40, 95% CI: 2.49-11.72), and white blood cell count >8550/μL: 2 points (OR = 2.76, 95% CI: 1.29-2.91) were found to be independently associated with SAG bacteremia. After totaling the above variables and adding 1 point for diabetes mellitus, the area under the receiver operating curve was 0.81 (95% CI: 0.74-0.88). The sensitivity and specificity were 51% and 88%, respectively, at a cut-off of 6 points.
CONCLUSIONS: In patients with VGS bacteremia, a score of 6 points or higher using this method predicts SAG with high specificity.

Three distinct streptococcal species: Streptococcus anginosus, Streptococcus intermedius, and Streptococcus constellatus, belonging to the Streptococcus anginosus group (SAG), also known as Streptococcus milleri group, have been attracting clinicians and microbiologists, not only as oral commensals but also as opportunistic pathogens. For years they have been simply classified as so called viridans streptococci, and distinct species were not associated with particular clinical manifestations. Therefore, description of SAG members are clearly underrepresented in the literature, compared to other medically relevant streptococci. However, the increasing number of reports of life-threatening infections caused by SAG indicates their emerging pathogenicity. The improved clinical data generated with the application of modern molecular diagnostic techniques allow for precise identification of individual species belonging to SAG. This review summarizes clinical reports on SAG infections and systematizes data on the occurrence of individual species at the site of infection. We also discuss the issue of proper microbiological diagnostics, which is crucial for further clinical treatment.