Humans ; Streptococcal Infections/microbiology* ; Streptococcus pyogenes/isolation & purification* ; Child ; China ; Consensus

OBJECTIVE: To investigate the risk factors, clinical characteristics, and bacterial resistance of bloodstream infections caused by Streptococcus mitis in children with hematological disease, so as to provide a reference for infection control. METHODS: The clinical information and laboratory findings of pediatric patients complicated with blood cultures positive for Streptococcus mitis from January 2018 to December 2020 in the Institute of Hematology & Blood Diseases Hospital were searched and collected. The clinical characteristics, susceptibility factors, and antibiotic resistance of the children were retrospectively analyzed. RESULTS: Data analysis from 2018 to 2020 showed that the proportion of Streptococcus mitis isolated from bloodstream infections in children (≤14 years old) with hematological diseases was the highest (19.91%) and significantly higher than other bacteria, accounting for 38.64% of Gram-positive cocci, and presented as an increasing trend year by year. A total of 427 children tested positive blood cultures, including 85 children with bloodstream infections caused by Streptococcus mitis who tested after fever. Most children experienced a recurrent high fever in the early and middle stages (≤6 d) of neutropenia and persistent fever for more than 3 days. After adjusting the antibiotics according to the preliminary drug susceptibility results, the body temperature of most children (63.5%) returned to normal within 4 days. The 85 children were mainly diagnosed with acute myeloid leukemia (AML), accounting for 84.7%. The proportion of children in the neutropenia stage was 97.7%. The incidence of oral mucosal damage, lung infection, and gastrointestinal injury symptoms was 40%, 31.8%, and 27.1%, respectively. The ratio of elevated C-reactive protein (CRP) and procalcitonin was 65.9% and 9.4%, respectively. All isolated strains of Streptococcus mitis were not resistant to vancomycin and linezolid, and the resistance rate to penicillin, cefotaxime, levofloxacin, and quinupristin-dalfopristin was 10.6%, 8.2%, 9.4%, and 14.1%, respectively. None of children died due to bloodstream infection caused by Streptococcus mitis. CONCLUSION The infection rate of Streptococcus mitis is increasing year by year in children with hematological diseases, especially in children with AML. Among them, neutropenia and oral mucosal damage after chemotherapy are high-risk infection factors. The common clinical symptoms include persistent high fever, oral mucosal damage, and elevated CRP. Penicillin and cephalosporins have good sensitivity. Linezolid, as a highly sensitive antibiotic, can effectively control infection and shorten the course of disease.
Humans ; Child ; Streptococcal Infections/microbiology* ; Retrospective Studies ; Hematologic Diseases/complications* ; Streptococcus mitis ; Drug Resistance, Bacterial ; Risk Factors ; Microbial Sensitivity Tests ; Anti-Bacterial Agents ; Female ; Male ; Bacteremia/microbiology* ; Child, Preschool ; Adolescent

OBJECTIVE: To explore whether streptococcal infection may aggravate renal damage in children with Henoch-Schönlein purpura nephritis and its possible mechanism. METHODS: In the study, 485 children diagnosed with Henoch-Schönlein purpura nephritis from July 2015 to December 2019 were selected to analyze their clinical data retrospectively. According to the diagnosis of discharge, whether it was combined with streptococcal infection, the children were divided into two groups. The experimental group contained 91 children with Henoch-Schönlein purpura nephritis combined with streptococcal infection, and there were 394 children who were not infected with Streptococcus in the control group. Suitable test items were preliminarily selected through artificial neural network, and then data analysis was performed through SPSS 23.0. RESULTS: The children with Henoch-Schönlein purpura nephritis infected with streptococcus had statistically significant differences compared with the uninfected children in the test items of urine protein, liver and kidney function, immunoglobulin and complement. Anti-streptolysin O had mild correlation with IgG (Spearman r=-0.328), fibrin degradation products (Spearman r=-0.207), total protein (Spearman r=-0.202) and globulin (Spearman r=-0.223). Compared with the children who were not infected with streptococcus, the differences of the average levels of age (P=0.001), IgG (P < 0.001), fibrin degradation products (P=0.019), total protein (P < 0.001), globulin (P < 0.001), IgA (P < 0.001), IgM (P=0.003), complement 3 (P=0.016), complement 4 (P=0.002), albumin/globulin ratio (P=0.007), alkaline phosphatase (P=0.036), and estimated glomerular filtration rate (P=0.039) in the infected children were statistically significant. In order to explore the risk factors of kidney damage in the children with Henoch-Schönlein purpura nephritis, Logistic regression was performed using anti-streptolysin O, age, immunoglobulin and complement as independent variables, urine protein detection parameters, liver and kidney functions as dependent variables. Age ≤10 years old and hypocomplementemia might be risk factors for aggravating renal damage in the children with Henoch-Schönlein purpura nephritis. CONCLUSION Streptococcal infections may aggravate renal damage in children with Henoch-Schönlein purpura nephritis, in which hypocomplementemia, inflammation, fibrinolysis and disorders of coagulation perhaps play an important role. Children with streptococcal infection should be treated with anti-infective treatment in time and necessarily, and followed up after discharge regularly.
Humans ; IgA Vasculitis/complications* ; Streptococcal Infections/complications* ; Child ; Male ; Female ; Nephritis/microbiology* ; Retrospective Studies ; Child, Preschool ; Kidney/pathology* ; Adolescent

Humans ; Young Adult ; Fusobacterium necrophorum ; Pharyngitis/microbiology* ; Streptococcal Infections ; Sepsis/diagnosis*

Group B streptococcus (GBS) is one of the severe pathogenic bacteria during the perinatal period, both on pregnant women and newborns. GBS infection may lead to pneumonia, septicemia, meningitis or other severe disease, even death in neonates. Although only 1%-2% infections will develop into GBS disease among the neonates, the etiological mechanism of which is worth researching. This review summarizes the possible factors related to GBS infection or occurrence of the disease, including the risk in gestation period (for example, colonization of GBS on vagina of pregnant women, preterm birth or premature rupture of fetal membranes and so on), related pathogens (bacteria strains, loads or virulence), immune level (inflammatory factor or neutralizing anticytokine auto-Abs), gene defect or primary immunodeficiencies of the hosts.
Female ; Humans ; Infant, Newborn ; Infectious Disease Transmission, Vertical ; Pregnancy ; Pregnancy Complications, Infectious/urine* ; Premature Birth ; Streptococcal Infections/urine* ; Streptococcus agalactiae/isolation & purification* ; Vagina/microbiology*

Objective: To analyze the characteristics of super-antigen (SAg) of group A Streptococcus pyogenes (GAS), isolated from patients with scarlet fever or pharyngeal infections in Beijing between 2015-2017. Methods: Throat swab specimens from patients with scarlet fever or pharyngeal infections were collected and tested for GAS. Eleven currently known SAg genes including SpeA, speC, speG, speH, speI, speJ, speK, speL, speM, smeZ and ssa were tested by real-time PCR while M protein genes (emm genes) were amplified and sequenced by PCR. Results: A total of 377 GAS were isolated from 6 801 throat swab specimens, with the positive rate as 5.5%. There were obvious changes noticed among speC, speG, speH and speK in three years. A total of 45 SAg genes profiles were observed, according to the SAgs inclusion. There were significant differences appeared in the frequencies among two of the highest SAg genes profiles between emm1 and emm12 strains (χ(2)=38.196, P<0.001; χ(2)=72.310, P<0.001). There also appeared significant differences in the frequencies of speA, speH, speI and speJ between emm1 and emm12 strains (χ(2)=146.154, P<0.001; χ(2)=52.31, P<0.001; χ(2)=58.43, P<0.001; χ(2)=144.70, P<0.001). Conclusions: Obvious changes were noticed among SAg genes including speC, speG, speH and speK from patients with scarlet fever or pharyngeal infections in Beijing between 2015-2017. SAg genes including speA, speH, speI and speJ appeared to be associated with the emm 1 and emm 12 strains. More kinds of SAg genes profiles were isolated form GAS but with no significant differences seen in the main SAg genes profiles, during the epidemic period.
Antigens, Bacterial/genetics* ; Bacterial Outer Membrane Proteins ; Bacterial Proteins ; Beijing/epidemiology* ; China/epidemiology* ; Exotoxins ; Female ; Humans ; Membrane Proteins ; Pharyngitis/microbiology* ; Pharynx/microbiology* ; Pregnancy ; Pregnancy Complications, Infectious/microbiology* ; Real-Time Polymerase Chain Reaction ; Scarlet Fever/microbiology* ; Streptococcal Infections ; Streptococcus pyogenes/isolation & purification* ; Superantigens/genetics*

BACKGROUND: We determined the epidemiological characteristics of erythromycin (EM)-resistant Streptococcus pyogenes (group A streptococci, GAS) strains isolated from Korea and Japan, using emm genotyping and multilocus sequence typing (MLST). METHODS: Clinical isolates of GAS had been collected from 1992 to 2012 in Korea and from 2004 to 2009 in Japan. EM resistance was determined by the microdilution method, and resistance genotypes were assessed by PCR. The emm genotyping and MLST were performed by DNA sequencing. RESULTS: The emm genotypes and sequence types (STs) were concordant in 143 (85.1%) of 168 EM-resistant GAS strains from Korea. ST36/emm12 (35.1%), ST52/emm28 (22.6%), and ST49/emm75 (16.1%) were the most common types. Most of the ST36 (93.9%) and ST52 (95.8%) strains harbored erm(B), whereas strains ST49, ST42, and ST15 contained mef(A). The concordance between emm genotypes and STs was 41 (93.2%) among 44 EM-resistant GAS strains from Japan. ST36/emm12 (34.1%), ST49/emm75 (18.2%), and ST28/emm1 (15.9%) were the major types. ST36 isolates harbored either erm(B) (56.3%) or mef(A) (37.5%), whereas isolates ST28, ST49, and ST38 carried only mef(A). The proportion of erm(B) and mef(A) was 66.1% and 33.3% in Korea and 22.7% and 68.2% in Japan, respectively. CONCLUSIONS: The common STs in Korea and Japan were ST36 and ST49, whereas ST52 was present only in Korea and ST28 only in Japan. Genotype erm(B) was predominant in Korea, whereas mef(A) was frequent in Japan. There were differences between Korea and Japan regarding the frequencies of emm genotypes, STs, and EM resistance genes among the EM-resistant GAS.
Anti-Bacterial Agents/*pharmacology/therapeutic use ; Bacterial Proteins/*genetics ; Bacterial Typing Techniques ; *Drug Resistance, Bacterial ; Epidemiologic Studies ; Erythromycin/*pharmacology/therapeutic use ; Genotype ; Humans ; Japan/epidemiology ; Microbial Sensitivity Tests ; Multilocus Sequence Typing ; Republic of Korea/epidemiology ; Streptococcal Infections/drug therapy/*microbiology ; Streptococcus pyogenes/drug effects/*genetics/isolation & purification

OBJECTIVETo study the clinical characteristics, pathogenic bacteria, and antibiotics resistance of neonatal purulent meningitis in order to provide the guide for early diagnosis and appropriate treatment.

METHODA retrospective review was performed and a total of 112 cases of neonatal purulent meningitis (male 64, female 58) were identified in the neonatal intensive care unit of Yuying Children's Hospital of Wenzhou Medical University seen from January 1, 2004 to December 31, 2013. The clinical information including pathogenic bacterial distribution, drug sensitivity, head imageology and therapeutic outcome were analyzed. Numeration data were shown in ratio and chi square test was applied for group comparison.

RESULTAmong 112 cases, 46 were admitted from 2004 to 2008 and 66 from 2009 to 2013, 23 patients were preterm and 89 were term, 20 were early onset (occurring within 3 days of life) and 92 were late onset meningitis (occurring after 3 days of life). In 62 (55.4%) cases the pathogens were Gram-positive bacteria and in 50 (44.6%) were Gram-negative bacteria. The five most frequently isolated pathogens were Escherichia coli (32 cases, 28.6%), coagulase-negative staphylococcus (CNS, 20 cases, 17.9%), Streptococcus (18 cases, 16.1%, Streptococcus agalactiae 15 cases), Enterococci (13 cases, 11.6%), Staphylococcus aureus (9 cases, 8.0%). Comparison of pathogenic bacterial distribution between 2004-2008 and 2009-2013 showed that Gram-positive bacteria accounted for more than 50% in both period. Escherichia coli was the most common bacterium, followed by Streptococcus in last five years which was higher than the first five years (22.7% (15/66) vs. 6.5% (3/46), χ(2) = 5.278, P < 0.05). Klebsiella pneumoniae was more common isolate in preterm infants than in term infants (13.0% (3/23) vs. 1.1% (1/89), χ(2) = 7.540, P < 0.05). Streptococcus (most were Streptococcus agalactiae) was the most common bacteria in early onset meningitis and higher than those in late onset meningitis (35.0% (7/20) vs. 12.0% (11/92), χ(2) = 4.872, P < 0.05). Drug sensitivity tests showed that all the Gram-positive bacterial isolates were sensitive to linezolid. Staphylococci were resistant to penicillin, and most of them were resistant to erythromycin, oxacillin and cefazolin; 77.8%of CNS isolates were methicillin-resistant staphylococcus. No Streptococcus and Enterococcus faecalis was resistant to penicillin. None of enterococci was resistant to vancomycin. Among the Gram-negative bacterial isolates, more than 40% of Escherichia coli were resistant to commonly used cephalosporins such as cefuroxime, cefotaxime and ceftazidime, and all of them were sensitive to amikacin, cefoperazone sulbactam and imipenem. Isolates of Klebsiella pneumoniae were all resistant to ampicillin, cefuroxime, cefotaxime and ceftazidime, but none of them was resistant to piperacillin tazobactam and imipenem. Of the 112 patients, 69 were cured, 23 improved, 9 uncured and 11 died. There were 47 cases (42.0%) with poor prognosis, they had abnormal head imageology, severe complications and some cases died, 13 of 18 (72.2%) patients with meningitis caused by Streptococcus died.

CONCLUSIONEscherichia coli, CNS and Streptococcus are the predominant pathogens responsible for neonatal purulent meningitis over the past ten years. There were increasing numbers of cases with Streptococcus meningitis which are more common in early onset meningitis with adverse outcome, therefore careful attention should be paid in clinic. Linezolid should be used as a new choice in intractable neonatal purulent meningitis cases caused by gram positive bacteria.

Anti-Bacterial Agents ; pharmacology ; Cefotaxime ; Child ; Drug Resistance, Bacterial ; Female ; Gram-Negative Bacteria ; Gram-Positive Bacteria ; Humans ; Imipenem ; Infant ; Infant, Newborn ; Infant, Newborn, Diseases ; Intensive Care Units, Neonatal ; Male ; Meningitis, Bacterial ; diagnosis ; drug therapy ; microbiology ; Methicillin-Resistant Staphylococcus aureus ; Microbial Sensitivity Tests ; Penicillins ; Retrospective Studies ; Staphylococcus ; Staphylococcus aureus ; Streptococcal Infections ; Streptococcus ; Streptococcus agalactiae

OBJECTIVETo investigate superantigen gene profiles of group A Streptococcus (GAS) isolated in Beijing pediatric patients in 2014, and to explore the the relationship between superantigen gene profiles with emm types, and GAS infections with diseases.

METHODSA total of 259 GAS strains were isolated from pediatric patients clinically who diagnosed with scarlet fever and pharyngitis from 36 hospitals in Beijing from May to July, 2014.The Superantigens genes of strains were performed by Real-time PCR (speA, speB, speC, speF, speG, speH, speI, speJ, speK, speL, speM, smeZ, ssa). PCR amplification of GAS strain M protein N gene segments were carried ort; products after sequencing comparison were analyzed to determine the GAS types of emm. The differences in distributions of superantigen genes and emm types of GAS isolates were compared between subgroups.

RESULTSAmong the 259 GAS strains, the detection rates of 13 superantigens were as the following: speA 48.6% (126), speB 99.2% (257), speC 99.2% (257), speF 98.8% (256), speG 98.5% (255), speH 43.6% (113), speI 46.3% (120), speJ 49.0% (127), smeZ 99.2% (257) and ssa 98.5% (255), respectively, however, speK, speL, and speM were not found. Eleven superantigen gene profiles in all were observed (A-K). The percentage of emm1 strains harbored spe A and speJ were 94.2% (113/120), 95.0% (114/120), respectively, which were significantly higher than those of emm12 strains (5.6% (7/124), 5.6% (7/124), respectively; χ(2) = 191.20, 194.80, P < 0.001). The percentage of emm12 strains harbored speH and speI were 83.9% (104/124), 88.7% (110/124), respectively, which were significantly higher than those of emm1 strains (3.3% (4/120), 4.2% (5/120), respectively; χ(2) = 160.30, 174.90, P < 0.001).The superantigen genotypes of GAS strains and emm types, which were isolated from scarlet fever and pharyngitis cases, were not significant different (P > 0.05).

CONCLUSIONThe GSA strains isolated in Beijing pediatric patients in 2014, the relevance ratio of speB, speC, speF, smeZ, speG, ssa were higher than others, while speK, speL, and speM were no detected in any GAS strains. The superantigen genes appeared to be associated with the emm type. Furthermore, emm type distribution and superantigen genes were not different between scalet fever and pharyngitis.

Antigens, Bacterial ; genetics ; Beijing ; Child ; Genotype ; Humans ; Real-Time Polymerase Chain Reaction ; Streptococcal Infections ; microbiology ; Streptococcus pyogenes ; genetics ; immunology ; Superantigens ; genetics

BACKGROUND: Viridans group streptococci (VGS) are both commensal microbes and potential pathogens. Increasing resistance to penicillin in VGS is an ongoing issue in the clinical environment. We investigated the difference in susceptibility and resistance to penicillin among various VGS species. METHODS: In total 1,448 VGS isolated from various clinical specimens were analyzed over a two-yr period. Identification and antimicrobial susceptibility test was performed by the automated VITEK 2 system (bioMerieux, France) or the MicroScan MICroSTREP system (Siemens, Germany). RESULTS: Among the 1,448 isolates, 412 were isolated from blood (28.4%). Streptococcus mitis group was the most frequently isolated (589 isolates, 40.7%), followed by the S. anginosus group (290 isolates, 20.0%), S. sanguinis group (179 isolates, 12.4%) and S. salivarius group (57 isolates, 3.9%). In total, 314 isolates could not be identified up to the species level. The overall non-susceptibility to penicillin was observed to be 40.0% (resistant, 11.2% and intermediately resistant, 28.8%) with uneven distribution among groups; 40.2% in S. sanguinis group (resistant, 5.0% and intermediately resistant, 35.2%), 60.3% in S. mitis group (resistant, 20.9% and intermediately resistant, 39.4%), 78.9% in S. salivarius group (resistant, 8.8% and intermediately resistant, 70.1%), and 6.2% in S. anginosus group (resistant, 1.7% and intermediately resistant, 4.5%). CONCLUSIONS: Antimicrobial resistance patterns towards penicillin show differences among various VGS; this should be considered while devising an effective antimicrobial treatment against VGS.
Anti-Infective Agents/*pharmacology ; Body Fluids/microbiology ; Drug Resistance, Bacterial ; Humans ; Microbial Sensitivity Tests ; Penicillins/pharmacology ; Streptococcal Infections/microbiology/pathology ; Viridans Streptococci/*drug effects/isolation & purification