Group B Strep (GBS) in pregnancy
- Created by: ljp101
- Created on: 20-02-20 13:03
View mindmap
- Group B Strep (GBS)
- GBS is a type of gram-positive streptococcal bacteria, aka. Steptococcus agalactiae.
- The type of common bacterium is commonly found in the human body (colonization), and is usually asymptomatic and intermittent.
- GBS is present in bowel flora of 20-40% of adults
- People who are colonised are called "carriers".
- The GBS carriage rate varies among racial groups, with the highest rate in people of black African ancestry and the lowest in people of south Asian ancestry.
- Gram positive and Gram Negative bacterium
- Difficult to treat gram-negative bacterium compared to gram-positive.
- There is a membrane present around the cell wall of gram-negative bacteria which increases the risk of toxicity to the host but this membrane is absent in gram-positive bacteria.
- Difficult to treat gram-negative bacterium compared to gram-positive.
- 2 Types of GBS infections in Babies
- Early Onset GBS (EOGBS) 0-6days (75%cases)
- 90% show within 12 hours
- Usually septicaemia and pneumonia
- 11% mortality
- 7% morbidity
- 90% preventable IV Penicillin
- Signs of EOGBS
- Grunting
- Lethargy
- Irritability
- Poor feeding
- Very high or low heart rate
- Low blood sugar
- Low blood pressure
- Abnormal (high or low) temperature
- Abnormal (fast or slow) breathing rates with blueness of the skin due to lack of oxygen (cyanosis)
- Management of EOGBS
- Observations (NEWS chart)
- Paediatrican
- Review possible/previous maternal risk factors
- Inform senior midwifery staff and obstetrician
- Debrief, document, Datex
- Ensure emergency resuscitation equipment on standby
- See RCOG 2017 guidelines
- Prevention of EOGBS
- A Cochrane review of three trials (all at high risk bias) including 500women concluded the IAP for colonised mothers reduced the incidence of EOGBS (relative risk 0.14; 95% CI 0.04-0.74) although the numbers of deaths were too small to assess the impact of the intervention on all-cause mortality.
- There have been no randomised studies addressing whether routine screening has had any impact on all-cause mortality
- The national Screening committee does not recommend universal bacteriological screening for GBS. Their view is that there is no clear evidence to show that testing for GBS routinely would do more good than harm
- Many women carry the bacteria and, in the majority of cases, their babies are born safely and without developing an infection
- Screening women late in pregnancy cannot accurately predict which babies will develop a GBS infection
- No screening test is entirely accurate, between 17% and 25% of women who have a positive swab at 35-37wks will be GBS negative at delivery. Between 5% and 7% of women who are GBS negative at 35-37wks will be GBS positive at delivery.
- Giving all carriers of GBS IAP would mean that a large number of women would receive treatment they do not need; this may increase adverse outcomes to mother and baby.
- A positive antenatal screen will result in the recommendation of IAP which carries some risk for mother and baby including, Anaphylaxis, increased medicalisation of labour.
- Most UK guidelines recommend that the first line drug for GBS-specific IAP should be Benzylpenicillin, also know as penicillin G
- Late Onset GBS (LOGBS) 7-90days (25% cases)
- Usually meningitis and septicaemia
- 8% mortality
- 21% morbidity (up to 50% with meningitis)
- No current prevention: good hygiene/education
- Signs of LOGBS
- Fever
- Poor feeding and/or vomiting
- Impaired consciousness
- Dislike of being handled, fretful
- tense or bulging fontanelle
- Involuntary body stiffening or jerking movements
- Floppy body
- Blank, staring or trance-like expression
- Turns away from bright lights
- Altered breathing patterns
- Pale and/or blotchy skin
- Management of LOGBS
- Urgent escalation according to Local Trust Guidelines
- Call for help (999 if in community)
- Continuous observations
- Ensure emergency resuscitation equipment on standby
- Review possible/previous maternal risk factors
- Debrief, document, datex
- see RCOG, 2017 guidelines
- Early Onset GBS (EOGBS) 0-6days (75%cases)
- GBS Prevention- Recommendation
- An effective vaccine given to pregnant women would be expected to induce high levels of GBS-specific immunoglobulin G in the women and, vie transplacental transfer, in her baby, resulting in protection against neonatal GBS
- Vaccine manufacturers are now developing pentavalent formulations (i.e. covering 5 of the 10 possible GBS serotypes) which would cover an estimated 96% of EOGBS cases in the UK.
- Studies in the UK suggest that vaccination against GBS would be acceptable to pregnant women.
- GBS Risk factors - identification
- Having a previous baby with GBS
- discovery of maternal GBS carriage through bacteriological investigation during pregnancy (for example. a urine infection or a swab taken to investigate a vaginal discharge)
- Pre-term birth
- Prolonged rupture of membranes
- Suspected maternal intrapartum infection, including suspected chorioamnionitis
- Pyrexia
- Management of GBS
- NICE (2014) Service providers (maternity care services) ensure that systems and protocols are in place to enable intrapartum antibiotic prophylaxis to be offered to pregnant women whose babies are at risk of Early onset neonatal infection, and insure that they are given the first dose as soon as possible
- Healthcare professionals adhere to protocols and offer intrapartum antibiotic prophylaxis to pregnant women whose babies are at risk of early onset neonatal infection, insuring that they are given the first dose as soon as possible and record this.
- Antibiotics for early onset neonatal infection (NICE, 2012) CG149 recommendation 1..3 1.2 states that if a woman decides to take intrapartum antibiotic prophylaxis, the first dose should be given as soon as possible. A suggested definition for audit purposes is that the first dose is given within 1 hour of the onset of active labour, or within 1 hour of admission if the woman is already in active labour.
- GBS is a type of gram-positive streptococcal bacteria, aka. Steptococcus agalactiae.
Comments
No comments have yet been made