Bacteremia because of Streptococcus pseudoporcinus in a Syphilis-HIV co-infected patient: A case report

Streptococcus pseudoporcinus bacteremia in a patient with skin and soft tissue infection. A case report and literature review

Streptococcus pseudoporcinus is a beta-hemolytic Streptococcus species arranged in short chains, which was first described in 2006. In the last years, there have been several reports of human infections by this bacterium, with five skin and soft tissue infections identified. Herein, a case of S. pseudoporcinus skin and soft tissue infection in a patient, who also developed bacteremia and was successfully treated with intravenous antibiotics, is reported. A 67-year-old man with a history of diffuse large B-cell lymphoma presented to the emergency department because of fever, redness, swelling, and pain in the left lower limb. He was admitted to the medical ward, diagnosed with severe non-purulent skin and soft tissue infection, and treated empirically with intravenous piperacillin/tazobactam at 4.5 gr thrice daily and daptomycin at 10mg/kg once daily. Blood cultures were obtained before the initiation of the antibiotics and grew S. pseudoporcinus. Treatment was de-escalated to ceftriaxone at a dose of 2 gr once daily. He completed two weeks of intravenous antimicrobial treatment. S. pseudoporcinus is an emerging pathogen associated with skin and soft tissue infections, bacteremia, and other invasive, potentially life-threatening infections. Further investigation is warranted to clarify this microorganism's pathogenesis and biological significance.

Endocarditis with Streptococcus pseudoporcinus Associated with Mastocytosis and Spondylodiscitis-A Coincidental Association? A Case Report

Streptococcus pseudoporcinus is a nonmotile Gram-positive, catalase, and benzidine negative, arranged in short chains, isolated from the genitourinary tract group B Streptococcus. S. pseudoporcinus was also identified from blood, urine, skin, cervical area, wounds, rectum, and placenta samples. Two cases of infective endocarditis have been reported in the literature. Based on these data, the identification of a case of S. pseudoporcinus infective endocarditis associated with spondylodiscitis in a patient with undiagnosed systemic mastocytosis until the age of 63 years is unusual. Two sets of blood specimens were collected, and both sets were positive for S. pseudoporcinus. Transesophageal echocardiography revealed, multiple vegetations on the mitral valve. A lumbar spine MRI revealed L5-S1 spondylodiscitis that associates prevertebral and right paramedian epidural abscesses with compressive stenosis. The performed bone marrow biopsy, and cellularity examination revealed 5-10% mast cells in the areas of medullary tissue, an aspect that is suggestive of mastocytosis. Antibiotic therapy was initiated, under which the patient presented intermittent fever. A second transesophageal echocardiography revealed a mitral valve abscess. A mitral valve replacement with a mechanical heart valve device through a minimally invasive approach was performed, with a favorable evolution under treatment. S. pseudoporcinus can be responsible for infectious endocarditis in certain immunodepressed cases, but also in a profibrotic, proatherogenic field, as shown by the association with mastocytosis in the presented case.

Case report: Multidrug-resistant Streptococcus pseudoporcinus isolated from an infected surgical wound of a 9-year-old spayed female Great Dane dog

Streptococcus pseudoporcinus (S. pseudoporcinus) is a β-hemolytic, Gram-positive novel bacterium first identified in 2006. It is a catalase-negative, non-motile coccus arranged in short chains. Furthermore, it has a broad beta-hemolytic reaction on sheep blood agar and cross-reacts with Lancefield group B antigen agglutination reagent. In this study, we report a case of S. pseudoporcinus infection of a surgical wound on the left metatarsus of a dog. The patient is a 9-year-old spayed female Great Dane dog with a brief history of multiple cutaneous masses being removed. Post-surgery, the post-surgical site on the left metatarsus became infected and discharged purulent material with a fetid odor. Upon preliminary diagnostic testing, we detected catalase-negative Gram-positive cocci exhibiting beta-hemolytic growth on sheep blood agar. A VITEK^® 2 Compact machine from bioMérieux identified the bacterium as S. pseudoporcinus. Furthermore, antibiotic testing revealed multidrug resistance. Therefore, we document a multidrug-resistant S. pseudoporcinus isolate as a cause of canine post-surgical wound infection. Furthermore, it was the only isolate detected from the sample; hence, it is the cause of the infection. To our knowledge, this case is the first report of S. pseudoporcinus in a dog.

Extensive Cellulitis and Bacteremia Due to Streptococcus Pseudoporcinus in a Child With Klippel-Trenaunay Syndrome

Streptococcus pseudoporcinus is a newly recognized β-hemolytic streptococcus, that is considered a rare pathogen in adults. Infections in children have not been reported. We describe a child with Klippel-Trenaunay syndrome that developed of S. pseudoporcinus cellulitis and bacteremia, which was difficult-to-treat, relapsed and required prolonged antibiotic courses. S. pseudoporcinus can cause invasive infection in children, especially in the presence of predisposing conditions.

Fatal Streptococcus pseudoporcinus disseminated infection in decompensated liver cirrhosis: a case report

Background

Streptococcus pseudoporcinus (S. pseudoporcinus) was first identified in 2006. It cross-reacts with Lancefield group B antigen agglutination reagents and has been misidentified as S. agalactiae. Sites of S. pseudoporcinus isolation include the female genitourinary tract, urine, wounds, and dairy products. The prevalence of vaginal colonization is reportedly between 1 and 5.4%. Two uneventful cases of soft tissue infection caused by S. pseudoporcinus were reported in the past. However, since late 2019, six cases of invasive S. pseudoporcinus infections have emerged in the literature, one of which was fatal.

Case presentation

We describe a fatal case of a Caucasian male with spontaneous bacterial peritonitis associated with bacteremia due to a multidrug-resistant S. pseudoporcinus strain in a patient with decompensated liver cirrhosis. Despite the patient’s good general condition and stable blood test results when he had visited the outpatient clinic for large-volume paracentesis a few days before admission, this time he presented to the emergency department with a rapidly worsening clinical condition and with laboratory features consistent with multiple-organ dysfunction syndrome, and succumbed within a short period.

Conclusions

Contrary to what was thought until recently, multidrug-resistant S. pseudoporcinus may cause invasive, disseminated, fatal disease in humans. According to current limited data, vancomycin, linezolid, daptomycin, levofloxacin, clindamycin, and tetracycline seem to be the most effective antimicrobial agents against multidrug-resistant strains, and should be the empirical choice in cases of disseminated S. pseudoporcinus infection until laboratory antimicrobial susceptibility results are available. Improvements and new approaches for bacterial identification in routine clinical microbiology laboratories may reveal the real spectrum of S. pseudoporcinus infections in humans, which is currently believed to be underestimated. SS. pseudoporcinus could emerge as a serious medical problem in the near future, similar to other β-hemolytic streptococci.