Streptococcus Gallolyticus Subsp. Pasteurianus Infection In A Neonatal Intensive Care Unit

Clinical Course and Outcomes of Infants with Streptococcus bovis/Streptococcus Gallolyticus subspecies pasteurianus Infection: A Systematic Review and Meta-analysis

BACKGROUND

Streptococcus gallolyticus subspecies pasteurianus (SGP), a subtype of Streptococcus bovis , is an uncommon but important cause of neonatal sepsis. Although uncommon, SGP infections during infancy have been associated with an increased risk of morbidity and mortality.

METHODS

This is a systematic review and meta-analysis of available literature on the clinical course and outcomes of infants with SGP infection. Studies were identified using the following MeSH keywords: " Streptococcus gallolyticus ," " Streptococcus bovis ," "newborn" and "infant." Data including perinatal factors, clinical presentation, investigations, treatment and outcomes were extracted and analyzed.

RESULTS

A total of 46 articles were identified (116 cases: 60 S. bovis , 56 SGP). The cases were predominantly term (52%), male (57%) and born via vaginal delivery (67%). The most common symptom was fever [67% (95% confidence interval (CI): 43%-84%)], lethargy [66% (95% CI: 32%-89%)], tachypnea [59% (95% CI: 27%-85%)] and irritability [59% (95% CI: 34%-79%)]. Infants with early-onset infections (<3 days of life) were more likely to have respiratory symptoms and bacteremia (73%), whereas late-onset infections presented predominantly with gastrointestinal symptoms. Four mortalities were reported which occurred before antibiotic administration. Isolated bacteria were mostly penicillin-susceptible [95% (95% CI: 78-99%)] and cases treated with penicillin derivative had good recovery.

CONCLUSIONS

SGP is an important cause of neonatal sepsis and meningitis. Penicillin derivative is an effective treatment for SGP, and outcomes appear to be favorable.

The Identification of Streptococcus pasteurianus Obtained from Six Regions in China by Multiplex PCR Assay and the Characteristics of Pathogenicity and Antimicrobial Resistance of This Zoonotic Pathogen

Streptococcus pasteurianus is a zoonotic pathogen causing meningitis and bacteremia in animals and humans. A lack of accurate and convenient detection methods hinders preventing and controlling diseases caused by S. pasteurianus. Additionally, there is limited knowledge about its pathogenicity and antimicrobial resistance characteristics, as there are only three complete genome sequences available. In this study, we established a multiplex PCR assay for the detection of S. pasteurianus, which was applied to six fecal samples from cattle with diarrhea and 285 samples from healthy pigs. Out of the samples tested, 24 were positive, including 5 from pig tonsils, 18 from pig hilar lymph nodes, and 1 from cattle feces. Two strains were isolated from positive samples, and their complete genomes were sequenced. The two strains were non-virulent in mice and multidrug-resistant by the antimicrobial susceptibility test. We first found the presence of genes tet(O/W/32/O) and lsa(E) in S. pasteurianus, leading to resistance to lincosamides and tetracyclines. The convenient and specific multiplex PCR assay provides essential technical support for epidemiological research, and the complete genome sequence of two non-virulent strains contributes to understanding this zoonotic bacterium's genomic characteristics and pathogenesis.

Neonatal Sepsis Caused by Streptococcus gallolyticus Complicated with Pulmonary Hypertension: A Case-Report and a Systematic Literature Review

Streptococcus gallolyticus (S. gallolyticus) has been linked to the development of infections in adults; however, in neonates S. gallolyticus sepsis is very rare and resembles Group B Streptococcal infections. In this case report, we present the case of a full-term neonate who developed early-onset sepsis due to S. gallolyticus. A systematic review of the literature was also conducted. The neonate had good APGAR scores at 1' and 5'. At 5 h postnatally, the neonate developed poor feeding and respiratory distress. She received oxygen in a head box, and a complete blood count and biochemistry, blood, CSF and body surface cultures were obtained. Empiric intravenous antibiotics (ampicillin and tobramycin) were initiated, and she was transferred to a tertiary NICU for further treatment. The neonate was mechanically ventilated and received dopamine and colloid fluids for circulatory support. A cardiology consultation revealed pulmonary hypertension on day one. S. gallolyticus was isolated in the blood culture. Central nervous system ultrasonography, brainstem auditory evoked potentials, and a second cardiology evaluation were normal on day three. Clinical and laboratory improvement was noted on day three, and the baby was discharged after a 12-day hospitalization. Follow-up visits were scheduled for reevaluation.

Invasive Streptococcus Gallolyticus Infections in Infants At Texas Children's Hospital: A 9-Year Retrospective Review

Streptococcus gallolyticus subsp. pasteurianus is an unusual pathogen in infants, which causes sepsis and meningitis. We describe the clinical course and treatment of 15 infants with bacteremia and/or meningitis due to S. gallolyticus. Outcomes were favorable with limited neuroimaging findings. One-third of isolates displayed reduced susceptibility to penicillin highlighting the importance of performing antimicrobial susceptibility testing in infants with meningitis.

Clinical Laboratory Features of Microbes That Cause Neonatal Sepsis: An 8-Year Retrospective Study

Purpose

To determine the distribution and antibiotic resistance patterns among pathogens that cause neonatal sepsis (NS) and to assess trends in antibiotic resistance.

Patients and methods

A total of 864 patients with sepsis admitted to a neonatal intensive care unit (NICU) between 2014 and 2021 were enrolled. Data on neonate age and sex, pathogenic microbes, and antimicrobial susceptibility were collected. Univariate and linear regression analyses were performed to determine the differences and trends in antibiotic resistance rates.

Results

The overall incidence rate of NS was 4.59 cases per 1000 live births. Of these cases, 255 (29.5%) were early-onset neonatal sepsis (EONS) and 609 (70.5%) were late-onset neonatal sepsis (LONS). A total of 670 (70.5%) gram-positive cocci and 171 (19.8%) gram-negative bacilli were identified. Among the 552 coagulase-negative Staphylococcus (CoNS) strains, the rate of oxacillin resistance was 70.6%, but no strains were resistant to linezolid, vancomycin or tigecycline. Among the antibiotic resistance patterns of the top three gram-negative pathogens, K. pneumoniae showed the highest rates of resistance, with resistance rates of 37.9% and 39.4% to ertapenem and imipenem, respectively, while E. coli and Enterobacter cloacae showed high levels of susceptibility to both. With regard to the trends in resistance among important pathogens, the rates of resistance to rifampicin, ciprofloxacin, levofloxacin, moxifloxacin and clindamycin by Staphylococcus epidermidis significantly decreased (p<0.05) during the study period. E. coli strains exhibited a significant increase in ceftriaxone resistance during the study period (p<0.05).

Conclusion

CoNS was the main microbe that caused NS, followed by E. coli. The bacterial isolates showed varying levels of resistance to the antimicrobial drugs tested. Thus, periodic surveillance in hospital settings to monitor changes in pathogens and antibiotic resistance is important.

Early-Onset Fulminant Sepsis in a Preterm Neonate due to Streptococcus gallolyticus : A Case Report and Literature Review

Streptococcus gallolyticus is an uncommon cause of neonatal infections. We describe the first case of fulminant lethal neonatal sepsis due to S. gallolyticus reported in literature. Our patient was an extremely low birth weight premature infant born to a mother with prolonged rupture of amniotic membranes and chorioamnionitis. We also review the cases of neonatal S. gallolyticus infections reported in literature. Fifty-eight percent neonatal S. gallolyticus infections presented in the first week of life. Importantly, S. gallolyticus meningitis is more commonly reported with early-onset infections compared with group B streptococcal meningitis, which is more common with late-onset infections. Streptococcus gallolyticus should be included in differential for neonatal sepsis, particularly in the presence of meningitis in the first week of life. Most cases are sensitive to penicillin; however, cases of reduced sensitivity to penicillin have also been reported.

Intrauterine infection and postpartum bacteremia due to Streptococcus gallolyticus subsp gallolyticus: An emerging concern

Streptococcus gallolyticus is a gram-positive coccus belonging to the family Streptococcus bovis/Streptococcus equinus complex (SBSEC). Most cases of SBSEC bacteremia are reported in elderly males with underlying hepatobiliary disease and associated with infective endocarditis (IE) or colonic malignancy. The gastrointestinal tract is the most common portal of entry, followed by the urinary tract and hepatobiliary tree. We present 5 cases of intrapartum bacteremia caused by S. gallolyticus subsp gallolyticus reported from the labor unit of our hospital from 2019 to 2021. There was histopathological or microbiological evidence of chorioamnionitis in each case. All the mothers were below the age of 35 years, and none of them had underlying hepatobiliary or colonic disease. All maternal antenatal screenings for group B streptococci (GBS) were negative. All the isolates were susceptible to penicillins, ceftriaxone, carbapenems, and vancomycin. Three of them were treated with ceftriaxone and two with aminopenicillins. Duration of treatment varied from 8 days to 14 days. None of the babies were low birth weight or pre-term. All but one baby had clinical sepsis requiring neonatal intensive care unit (NICU) stay, with one having evidence of meningitis and three respiratory distress syndromes (RDS). None of the babies had S. gallolyticus bacteremia. All mothers and babies made a complete recovery without any complications. These cases suggest that S. gallolyticus subsp gallolyticus can be a rare but emerging cause of intrauterine infection complicated by post-partum bacteremia. There is possibility of colonization of maternal genital tract with S. gallolyticus causing neonatal infection.

Streptococcus gallolyticus subspecies pasteurianus causing early onset neonatal sepsis complicated by solitary liver abscess in a preterm infant

Streptococcus gallolyticus ssp pasteurianus (SGp) is an uncommon but increasingly recognized cause of neonatal sepsis and meningitis. Liver abscess in neonates is extremely rare. But liver abscess due to SG has never been reported in the literature. We present the first case of liver abscess due to SGp in a late preterm infant. A female infant was born at 36 weeks via normal vaginal delivery to a mother with unremarkable antenatal history. She had progressively worsening respiratory distress since birth and was intubated at 13 h of life. One dose of surfactant was delivered and ventilation continued. Parenteral crystalline Penicillin and Gentamicin were initiated and her blood culture at birth grew SGp. She had a spike of fever on day 5 of life. An ultrasound (US) scan of the abdomen was included in the septic work up. A multi-septated cystic liver abscess was noted in the right lobe of the liver. As there was inadequate response to appropriate intravenous antibiotics, needle aspiration and biopsy were performed on day 35 of life. Aspirate was sterile and histopathology confirmed a liver abscess. The patient continued to be treated with antibiotics for 8 weeks with serial US scans of the liver showing resolution of the abscess. Increasing awareness among paediatric and neonatal fraternity about these new emerging bacterial infections can facilitate early diagnosis and treatment.

Clustering of Streptococcus gallolyticus subspecies pasteurianus bacteremia and meningitis in neonates

BACKGROUND/PURPOSE

Although Streptococcus gallolyticus subspecies pasteurianus (SGSP) is a rare pathogen in children, it can cause invasive infections among neonates and infants. Herein, we report bacteremia/meningitis caused by SGSP in three neonates and review the literature on bacteremia and/or meningitis caused by this organism.

METHODS

Three neonates, referred from an obstetrics clinic within a 2-month period, presented with invasive SGSP infections. The bacterial isolates were analyzed using Bruker Biotyper MALDI-TOF, sequencing of 16S rRNA and sodA genes (encoding manganese dependent superoxide dismutase), and PCR restriction fragment length polymorphism assay of groESL gene. Molecular typing was performed to evaluate the genetic relatedness.

RESULTS

The median onset age of infection in the three neonates was 3 days (range 2-5 days). They were delivered through cesarean section in the same operation room under different doctors, and were cared for by different nurses. Patient A presented with bacteremia, patient B with bacteremia and meningitis, and patient C with meningitis. Four isolates were identified as SGSP and were susceptible to penicillin G, cefotaxime, and vancomycin. All patients were treated with ampicillin plus cefotaxime for 14 days, and no complications were observed. The molecular typing results suggested that all isolates belonged to a single clone, which indicated the possibility of an outbreak in the obstetrics clinic.

CONCLUSION

Infection by a rare pathogen such as SGSP in multiple patients belonging to a single healthcare unit indicates that detailed investigation and stringent infection control policy are necessary for preventing further outbreaks of such diseases.

Microbiological and clinical characteristics of Streptococcus gallolyticus subsp. pasteurianus infection in China

BACKGROUND

Infections by Streptococcus gallolyticus subsp. pasteurianus (SGSP) is often underestimated. Herein, the epidemiological features and resistant characteristics of SGSP in mainland China are characterized to enable a better understanding of its role in clinical infections.

METHODS

In the present work, 45 SGSP isolates were collected from the samples of bloodstream, urine, aseptic body fluid, and fetal membrane/placenta from patients in 8 tertiary general hospitals of 6 cities/provinces in China from 2011 to 2017. The identification of all isolates was performed using traditional biochemical methods, 16S rRNA and gyrB sequencing, followed by the characterization of their antibiotic resistance profiling and involved genes.

RESULTS

Among 34 non-pregnancy-related patients, 4 (4/34,11.8%) patients had gastrointestinal cancer, 10 (10/34, 29.4%) patients had diabetes, and one patient had infective endocarditis. Moreover, 11 cases of pregnant women were associated with intrauterine infection (9/11, 81.2%) and urinary tract infection (1/11, 9.1%), respectively. Except one, all other SGSP isolates were correctly identified by the BD Phoenix automated system. We found that all SGSP isolates were phenotypically susceptible to penicillin, ampicillin, cefotaxime, meropenem, and vancomycin. Forty strains (40/45, 88.9%) were both erythromycin and clindamycin-resistant, belonging to the cMLS_B phenotype, and the majority of them carried erm(B) gene (39/40, 97.5%). Although the cMLS_B/erm(B) constituted the most frequently identified phenotype/genotype combination (25/40, 62.5%) among all erythromycin-resistant cMLS_B isolates, erm(B)/erm(A), erm(B)/mef(A/E), and erm(B)/erm(T) was detected in 7, 4, and 3 isolates, respectively. Furthermore, 43 strains (43/45, 95.6%) were tetracycline-resistant, and out of these, 39 strains (39/45, 86.7%) carried tet(L), 27(27/45, 60.0%) strains carried tet(O), and 7 (7/45, 15.6%) strains carried tet(M), alone or combined, respectively. All erythromycin-resistant isolates were also resistant to tetracycline.

CONCLUSIONS

It is important to study and draw attention on SGSP, an underreported opportunistic pathogen targeting immunodeficient populations, notably elderly subjects, pregnant women and neonates.

Neonatal meningitis, endocarditis, and pneumonitis due to Streptococcus gallolyticus subsp. pasteurianus: a case report

Background

Streptococcus pasteurianus is a rare cause of neonatal infection, with only 3 cases reported in the USA and 18 cases reported in other countries within the past decade. Neonatal S. pasteurianus infection typically presents as meningitis. This case report describes the first neonatal case of S. pasteurianus endocarditis in the literature, in addition to a neonatal case of S. pasteurianus infection presenting as pneumonitis without meningitis. The S. pasteurianus infections in these two cases are unusual not only because of how rare this particular pathogen is, but also because of the atypical clinical manifestations.

Case presentation

The first patient is a full-term male infant admitted to NICU at 20 h of life due to respiratory distress. He was empirically started on ampicillin and gentamicin for presumed sepsis. Laboratory analysis of cerebral spinal fluid obtained after initiation of antibiotics was suggestive of partially treated meningitis. Blood cultures came back positive for S. pasteurianus. The neonate was transitioned from ampicillin to cefepime, while gentamicin was continued. Echocardiograph showed a possible tricuspid valve vegetation concerning for endocarditis. Due to the unusual complication of endocarditis, the patient remained on IV cefepime for 28 days rather than the more conventional duration of 14–21 days reported in the literature. The baby clinically improved with no evidence of thrombi or vegetations on repeat cardiac echo.

The second patient is a full-term male infant who required intubation at birth for respiratory distress. Chest X-ray findings were concerning for meconium aspiration with pneumonitis. The baby went into septic shock and was empirically started on ampicillin and gentamicin. Blood cultures came back positive for S. pasteurianus, while cerebral spinal fluid and urine cultures were negative. Ampicillin and gentamicin were discontinued after 3 days and the baby was started on cefepime and clindamycin for a total 14-day course. The baby clinically recovered and was discharged from NICU without any sequelae.

Conclusions

These two cases highlight the importance of recognizing S. pasteurianus as a potential cause of neonatal sepsis and the importance of recognizing endocarditis and pneumonitis as possible clinical manifestations of this infection.

Inducible Expression of both ermB and ermT Conferred High Macrolide Resistance in Streptococcus gallolyticus subsp. pasteurianus Isolates in China

Streptococcus gallolyticus subsp. pasteurianus is an under-recognized pathogen and zoonotic agent causing opportunistic infections in humans. Despite increasing recognition of this subspecies as a cause for human infectious diseases, limited information is known about its antibiotic resistance mechanism. In this study, we aim to identify the molecular mechanism underlying the high macrolide resistance of six S. gallolyticus subsp. pasteurianus isolates from dead ducklings collected in several natural outbreaks in China during 2010–2013. All isolates exhibited multi-drug resistance including high macrolide resistance (MIC ≥ 1024 mg/L for erythromycin, and 512 mg/L for clarithromycin). Efflux-encoding mefA and mefE genes were not detectable in these isolates. The presence of 23S rRNA mutations in specific isolates did not significantly change macrolide MICs. No nucleotide substitutions were found in genes encoding ribosomal proteins L4 or L22. The ermB and ermT genes were found in the genomes of all isolates. These two genes were acquired independently in one highly virulent isolate AL101002, and clustered with Tn916 and IS1216, respectively. The expression of both ermB and ermT in all isolates was erythromycin inducible and yielded comparable macrolide MICs in all six isolates. Taken together, inducible expression of both ermB and ermT conferred high macrolide resistance in these S. gallolyticus subsp. pasterianus isolates. Our findings reveal new macrolide resistance features in S. gallolyticus subsp. pasteurianus by both ermB and ermT.