Blood Heart Infusion Research Articles

Unusual case of multiple hepatosplenic abscesses caused by Staphylococcus aureus

Background: Combined liver and splenic abscesses are very rare in people without underlying diseases or immune-deficiencies, and can be fatal. Clinical presentation may not be straight-forward. Case description: A 19 year old male was admitted to the Emergency Unit with 2 days fever, left-sided loin pain and vomiting. After examination, the patient was admitted to a medical ward with a presumptive diagnosis of urinary tract infection. Physical examination revealed signs of an acute abdomen and the patient was referred to a surgeon. On further history, a fall from a tree with blunt trauma to the abdomen was elicited. Splenic rupture was suspected and confirmed by ultrasound scan abdomen. Laparotomy was performed. The spleen was lacerated in several places with peri-splenic haematoma formation. Splenectomy was performed. Multiple small abscess-like lesions were observed on the liver and biopsies were taken and sent for microbiology and histopathology. Meropenem was started post-operatively on a presumptive diagnosis of melioidosis and clindamycin. Primary culture of liver tissue showed no growth after 24 hour incubation. A pure growth of Staphylococcus aureus sensitive to cloxacillin was obtained on enrichment of the tissues in Blood Heart Infusion broth. Treatment was changed to intravenous cloxacillin and ciprofloxacin and the patient kept under strict observation. The histopathology report revealed colonies of Gram positive cocci in the biopsies taken from the liver and spleen. Size of the lesions in the liver initially increased up to 1 cm and then gradually reduced. Inflammatory markers (CRP, FBC), too, initially increased, then gradually normalized. Serology by the indirect hemagglutination assay for Burkholderia pseudomallei antibody was negative. Patient was fever free by the 5th day. Computed tomography chest, abdomen and head were done to exclude abscesses in other organs and 2D-echocardiogram to exclude endocarditis. The patient was treated with IV cloxacillin for 6weeks and discharged on oral cloxacillin for 3 weeks after giving vaccines as indicated in asplenism. Discussion: Atypical presentation of hepatosplenic abscesses may lead to misdiagnosis. Vigilance and open-mindedness for unusual manifestation of hepatosplenic abscesses on the differential diagnosis, even in patients without any risk factors, may improve the prognosis. Conclusion: Awareness and vigillance for atypical infections is life saving.

Biofilm formation by ESBL-producing strains of Escherichia coli and Klebsiella pneumoniae

ObjectivesBiofilm production in extended spectrum β-lactamase (ESBL)-producing Enterobacteriaceae provides a favourable environment for the exchange of antibiotic-resistance genes and could facilitate widespread dissemination. We aimed to assess biofilm development in ESBL-producing E. coli and K. pneumoniae isolates and determine how development relates to microbiological characteristics and clinical outcomes. Methods147 ESBL-producing E. coli and 82 K. pneumoniae were genetically characterized. Biofilm formation was measured at 1.5, 4, 6, and 24 h during culture in blood heart infusion using a microbead immobilization assay (BioFilm Ring test®). Results were given as biofilm formation index (BFI) with lower values indicating increased presence of biofilm (range = 0–21). ResultsIn total, 57.1% of strains were strong producers of biofilm (BFI < 2), whereas 13.4% lacked biofilm production (BFI > 18). Standard biofilm production (BFI < 7) was common in E. coli isolates (61.9%). For E. coli, biofilm production was less frequently observed in ST131 clones (p = 0.03) but more frequently in strains harbouring toxin (p = 0.008) or adhesin (p = 0.008) virulence factor genes. Despite almost all K. pneumoniae having standard biofilm production (90.2%), there was a 2.4-times higher odds of observing biofilm in ST29/147/323 versus other ST-types (p = 0.13). Patients with standard biofilm producing isolates were not at increased risk of transfer to intensive-care (odds-ratio=2.80, 95%CI=0.59–13.21) or death within 12-months (odds-ratio=1.61, 95%CI=0.75–3.43). ConclusionIn these ESBL-producing strains, biofilm production is linked to certain virulence factors in E. coli and is common in K. pneumoniae. Further exploration of whether biofilm production increases dissemination and risk of severe clinical outcomes is needed in larger collections of isolates.

Genome Sequence of Mannheimia haemolytica Serotype 1 Strain 16041065 BH.

ABSTRACTHere, we report the genome sequence of Mannheimia haemolytica serotype 1 strain 16041065 BH, which was recently isolated from a Midwestern calf that died due to Mannheimia haemolytica–induced pneumonia. This genome comprised a total of 2.7 Mb, with an N50 of 122 kb, and maintained hemolytic activity when grown on blood heart infusion agar supplemented with 5% sheep’s blood.

Root canal disinfection comparing conventional irrigation vs photon-induced photoacoustic streaming (PIPS) using a buffered 0.5 % sodium hypochlorite solution

Abstract Background The purpose of this study was to assess the antimicrobial effect of a buffered 0.5 % sodium hypochlorite solution activated by photon-induced photoacoustic streaming compared to conventional irrigation. Methods The canals on 48 single canal lower bicuspids were cleaned and shaped using rotary instrumentation. All roots were autoclaved for 20 min. Thirty-six of the roots were placed in glass flasks with blood heart infusion media and Enterococcus faecalis (ATCC 4082) for 4 weeks. The remaining 12 roots were placed in a sterile environment and served as negative controls. The contaminated roots were irrigated by conventional means using a buffered 0.5 % sodium hypochlorite solution with or without photon-induced photoacoustic streaming (PIPS) activation (n = 12 each group). The remaining 12 roots did not receive any treatment and served as positive controls. The apical 3 mm of each tooth was sectioned and pulverized. The pulverized samples were collected and placed in Eppendorf micro-centrifuge tubes with sterile phosphate-buffered saline. Thirty MicroLiters of the collected samples was then placed in the blood heart infusion media and incubated for 24 h at 37 °C. Colony forming units (CFU) were compared with Wilcoxon signed ranked test. Mann-Whitney U test was used to assess PIPS effectiveness in comparison with conventional irrigation. Results Both regimens reduced significantly the number of CFU; however, reduction was significantly higher for the PIPS group (p = 0.002). Conclusion Buffered 0.5 % sodium hypochlorite delivered by conventional method was effective in removing E. faecalis from contaminated root canals; however, activation of a buffered 0.5 % sodium hypochlorite solution by PIPS significantly increased its antimicrobial capacity.

Stamp-Form Contact Plate: A Simple and Useful Culture Method for Microorganisms of the Skin

Stamp-Form Contact Plate: A Simple and Useful Culture Method for Microorganisms of the Skin

Effectiveness of different chemical agents for disinfection of gutta‐percha cones

This aim of this study was to evaluate and compare the efficacy of different chemical methods to disinfect gutta-percha cones (GP). Eighty-six size 80 GP cones were used. The cones were contaminated by immersion in saliva and Enterococcus faecalis. Four chemical agents were used: 1% sodium hypochlorite (G1), 2% chlorhexidine gluconate (G2), 10% povidone iodine (G3) and 0.9% saline solution (G4). GP cones were immersed in the solutions for periods of 1 and 10 min. After the disinfection procedure, the cones were incubated in blood heart infusion and the presence of bacterial growth was analysed by turbidity of the medium. In G4, bacterial growth was observed in all specimens; G3 showed growth after immersion for 1 min when contaminated with E. faecalis; G1 showed diverse results after the immersion for 1 min. Meanwhile, G1 and G3 after 10 min, and G2 at both times evaluated did not show bacterial growth. The immersion of GP cones in 2% chlorhexidine gluconate for 1 min was an effective method for GP disinfection, while 10% povidone iodine and 1% sodium hypochlorite needed 10 min of immersion to disinfect the GP.

Study of haemolytic activity of some Campylobacter spp. on blood agar plates

A total of 152 strains of Campylobacter jejuni, C. coli, C. laridis and C. fetus subsp. fetus were tested for haemolysis on blood agar plates. Distinct haemolysis was detected in 92.3% (96/104) of strains of C. jejuni and 21.7% (5/23) of strains of C. coli on sheep blood heart infusion agar after incubation for 4 d microaerobically at 42 degrees C. Haemolysis was also detected on horse blood heart infusion agar. Haemolysis was not detected at 37 degrees C except with one of 50 strains of C. jejuni tested at this temperature, which was weakly positive. Campylobacter laridis was not haemolytic; C. fetus subsp. fetus, which does not grow at 42 degrees C, showed no haemolysis at 37 degrees C. Blood agar (Oxoid, BA Base No. 2) was not suitable for testing for haemolysis by these organisms. A microaerobic gas mixture containing hydrogen is better than that containing nitrogen because the medium has a brighter colour, making haemolysis easier to detect. There was no synergistic haemolysis with Staphylococcus aureus or Streptococcus agalactiae. The plate haemolysis test as described here may aid differentiation within the thermophilic campylobacters.

A medium for the recognition and enumeration of Streptococcus mutans

A solid medium is described, whereon colonies of Streptococcus mutans can be recognized and enumerated in samples of dental plaque that have a high count of that organism. On the same medium, an estimate of “total bacteria” can be obtained to serve as a convenient base line. Colony counts of Strep. mutans from plaque samples averaged 50 per cent higher on this medium than on mitis-salivarius agar; the counts of “total bacteria” were comparable to those on blood-heart infusion agar.

Production of double zones of hemolysis by certain strains of hemolytic streptococci of groups A, B, C, and G on heart infusion agar.

This report describes the appearance of a double zone of hemolysis around surface colonies of certain strains of streptococci of groups A, B, C, and G incubated aerobically on sheep blood-Heart Infusion Agar. The occurrence of the altered hemolytic pattern was related to peroxide production by the organism. Anaerobic conditions and the incorporation of catalase into the agar abolished the double-zone pattern and caused reversion of the organisms to a beta-hemolytic pattern. The double-zone pattern can be confused with alpha hemolysis on surface growth.

Production of Double Zones of Hemolysis by Certain Strains of Hemolytic Streptococci of Groups A, B, C, and G on Heart Infusion Agar

This report describes the appearance of a double zone of hemolysis around surface colonies of certain strains of streptococci of groups A, B, C, and G incubated aerobically on sheep blood-Heart Infusion Agar. The occurrence of the altered hemolytic pattern was related to peroxide production by the organism. Anaerobic conditions and the incorporation of catalase into the agar abolished the double-zone pattern and caused reversion of the organisms to a beta-hemolytic pattern. The double-zone pattern can be confused with alpha hemolysis on surface growth.

Role of suspending and recovery media in the survival of frozen Shigella sonnei.

Shigella sonnei was frozen at -20 C in saline, nutrient broth, and milk, and plated, after thawing, upon synthetic medium, nutrient agar, and blood heart infusion agar. There was a difference in the numbers of cells recovered when the frozen and thawed cells were grown on different media. The synthetic medium was unable to recover cells injured by freezing or did so only poorly compared to the complex media. The addition of meat extract, peptone, or Casamino acids to the synthetic medium improved its ability to recover injured cells as measured by bacterial colony counts. This is suggestive of metabolic injury caused by the freezing processes since the cells which survived freezing required an enriched medium for growth. In this paper the term metabolic injury is used to express a change in the nutritional requirements of the organisms which resulted in an increase in growth factor requirements. Freezing the cells in saline resulted in greater injury compared to cells frozen in nutrient broth or milk; this suggested that these suspending agents possessed some protective quality. The metabolic injury increased with an increase in the length of time the cells were held in the frozen state.

Role of Suspending and Recovery Media in the Survival of Frozen Shigella sonnei1

Shigella sonnei was frozen at -20 C in saline, nutrient broth, and milk, and plated, after thawing, upon synthetic medium, nutrient agar, and blood heart infusion agar. There was a difference in the numbers of cells recovered when the frozen and thawed cells were grown on different media. The synthetic medium was unable to recover cells injured by freezing or did so only poorly compared to the complex media. The addition of meat extract, peptone, or Casamino acids to the synthetic medium improved its ability to recover injured cells as measured by bacterial colony counts. This is suggestive of metabolic injury caused by the freezing processes since the cells which survived freezing required an enriched medium for growth. In this paper the term metabolic injury is used to express a change in the nutritional requirements of the organisms which resulted in an increase in growth factor requirements. Freezing the cells in saline resulted in greater injury compared to cells frozen in nutrient broth or milk; this suggested that these suspending agents possessed some protective quality. The metabolic injury increased with an increase in the length of time the cells were held in the frozen state.