Infectious Diseases In Pregnancy Flashcards
U.K. prevalence of TB
4.2 per 100, 000
World wide prevalence of TB in pregnant women
0.25% low prevalence country
0.5% high prevalence country
11% in HIV positive women
Mycobacterium tuberculosis organism characteristics
Aerobic
Non-spore forming
Non-motile bacillus
Primary TB
Disease within 2 years of infection
Latent TB
Asymptomatic and non-infectious
Sites of extra pulmonary disease in pregnancy
Cervical lymph nodes (31%)
CNS
abdomen
Pericardium
Effects of TB on perinatal outcomes
Low APGAR
RDS with extra pulmonary disease
Preterm delivery
SGA
Oligohydramnios
PPROM
Effects of TB on maternal outcomes
Hypertension
Cholestasis
GDM
Anaemia
Death
Associations with HIV-TB coinfection
Anaemia
Eclampsia
Placenta accepts
Drug abuse
Depression
Treatment of TB (no CNS involvement)
Initial phase (2 months) - rifampicin, isoniazid, ethambutol and pyrazinamide
Continuation phase (4 months) - rifampicin and isoniazid
*give pyridoxine
Treatment of TB with CNS involvement
Rifampicin, isoniazid, pyrazinamide and ethambutol for 2 months
Rifampicin and isoniazid for 10 months
Dexamethasone/prednisone for 4-8 weeks
*Give pyridoxine
Treatment of drug resistant TB
Continue 3 drug treatment for 2 months followed by continuation with sensitive agents for 4-7 months
Most common infective site of TB in the neonate
Liver
Diagnostic tests for perinatal TB
Placental histology and culture
CXR
CSF culture
GI/tracheal aspirated
Presentation of perinatal TB
RDS
Failure to thrive
Irritability
Lymphadenopathy
Pyrexia of unknown origin
Unexplained anaemia
Hepatosplemomegaly
Perinatal TB mortality
22% treated infants
38% non-treated infants
Breastfeeding in TB
Safe after completion of 2 weeks Rx
Not safe if multi-drug resistant or HIV coinfection
BGC vaccination recommendation
If neonate is in a high prevalence area 40/10000
If close relatives are from high incidence countries (40/100000)
If born to HIV mum, formula fed and HIV negative at 14 weeks
Commonest causative organisms for obstetric sepsis
Streptococcal groups A, B, D
Pneumococcus
E. coli
Septic shock management
If lactate >4 or hypotension is present then:
30ml/kg crystalloid within 3 hours of diagnosis
Vasopressor or inotrope to maintain MAP 65mmHg
Measure cardiac output with oesophageal Doppler or lithium dilution cardiac output (LiDCO)
Consider steroids if inadequate response to vasopressors
Remove septic focus
Thromboprophylaxis
+/- blood products
Who gets offered IAP for GBS
Preterm labour
GBS colonisation during current pregnancy
Previous baby with GBS disease
Clinical diagnosis of chorioamnionitis
Management of previous GBS colonisation in a previous pregnancy
Collect swab between 35-37 weeks or 3-5 weeks before expected delivery
If positive then offer IAP
GBS antibiotic choice (no allergy)
Benzylpenicillin if no chorioamnionitis
Add gentamicin if clinical chorioamnionitis
GBS treatment (mild penicillin allergy)
Cephalosporin with GBS activity with caution if no chorioamnionitis
Cephalosporin with metronidazole if clinical chorioamnionitis
GBS treatment (severe penicillin allergy)
Vancomycin or sensitivity guided choice if no chorioamnionitis
Vancomycin + gentamicin + metronidazole if clinical chorioamnionitis
When to deliver PPROM with GBS?
34-37 weeks
Incidence of early onset GBS disease
0.57/1000
Risk of disability with early onset GBS disease
7.4%
Recurrent GBS carriage in subsequent pregnancy risk
50%
Risk of early onset GBS if positive swab in a subsequent pregnancy
1 in 400
Incidence of early onset GBS if negative swab in subsequent pregnancy
1 in 5000
Incidence of GBS with maternal pyrexia in labour
5.3 per 1000
Risk of mortality from sepsis
8%
Risk of mortality from early onset neonatal GBS
5%
Percentage of maternal deaths caused by sepsis
10%
Sepsis MBRRACE data
5th commonest cause of death
(4th if covid is excluded)
10% of deaths
2.5 deaths per 100,000
Malaria species that causes cerebral complications
P falciparum
What type of parasite is malaria?
Protozoan
Malaria species which lie dormant (hypnozoites) in the liver
P vivax
P ovale
How long does immunity from malaria last?
2 years
Risk factors for malaria infection and severe disease
2nd trimester
Primigravida
Young maternal age
Maternal complications of malaria
Anaemia
Cerebral malaria
ARDS
Hypoglycaemia
Renal failure with haemoglobinuria
DIC
Fetal complications of malaria
Miscarriage
PTB
SGA
IUFD/neonatal death
fetal anaemia
Congenital malaria (parasites in placenta in 25% cases)
Failure to thrive
Coinfection
Hepatic phase of malaria lasts for
7 days
Merozoite reproduction in Erythrocytes takes . . .
48 hours for p. Falciparum, vivax and ovale
72h for P. Malariae
Erythrocytic phase of malaria lasts
4 weeks
Drug excretion time for malaria prophylaxis agents
Doxycycline - 1 week
Mefloquine - 3 months
Proguanil - 1 week
Atovaquone and proguanil - 2 weeks
Contraindications to mefloquine
Depression
Neuro-psychiatric disorders
Epilepsy
Hypersensitivity to quinine
Anti-malaria agent in 2nd/3rd trimester or breast feeding
Mefloquine
Malaria treatment
Uncomplicated - hospital admission, PO/IV quinine and clindamycin for P. Falciparum/vivax
Complicated - ICU admission, IV artesunate for P.falciparum
Chloroquine for p. Vivax/ovale/malariae
Primaquine contraindicated
Symptoms of malaria
Cyclical Fever, cough, joint pains, anaemia, vomiting, headache, dark urine
Severe - jaundice, seizures, prostration, breathing difficulties, impaired consciousness and abnormal bleeding
Clinical signs of malaria
Hepatosplenomegaly
Retinal damage on fundoscopy
Hypovolaemic shock
Pulmonary oedema
Diagnosis of malaria
Blood film microscopy - 3 negative blood films 12-24hrs apart excludes malaria
Rapid detection tests for antigens are less sensitive than microscopy
Complicated malaria is characterised by
Hypoglycaemia/hyperglycaemia
ARDS
Impaired consciousness
Severe anaemia <8
DIC/abnormal bleeding
Haemoglobinuria
Renal impairment
Acidosis
Hyperlactaemia
Hyper parasitaemia (>2% red cells infected)
Circulatory shock
Neonatal management following malaria
Screen thick and thin blood films at north and weekly for 28 days
CMV is a ______ virus
Double stranded DNA
CMV primary infection happens in what proportion of pregnant women?
2%
Neonatal CMV mortality
20-30%
Fetal risks from CMV
Sensorineural deafness (commonest cause)
Hepatosplenomegaly
IUGR
Microcephaly and learning disability
Thrombocytopenia
Haemolytic Anaemia
Jaundice
Seizures
Toxoplasmosis is caused by
Toxoplasmosis gondii
Incubation period for toxoplasmosis
5-23 days
Toxoplasmosis Gondii is ____
Obligate Intracellular protozoan
Toxoplasmosis is spread via
Contaminated food
Rate of toxoplasmosis infection in pregnancy
1 in 500
Absence of ____ antigen is protective against P Vivax
Duffy antigen found in black people
Treatment to prevent relapse of malaria in pregnancy
Oral chloroquine 300mg weekly until delivery
MOD with Hep B or C
Vaginal birth not contraindicated
Caesarean birth if Hepatitis C and HIV co-infection
Diagnosis of Zika virus
RT-PCR IgM
Cross reacts with yellow fever and dengue
Length of time to avoid pregnancy after exposure to Zika virus
3 months if make partner travelled
2 months if female partner travelled
Management of microcephaly secondary to Zika infection
If Hc <2 SD below mean for gestational age >20 weeks
Advise for fertility after Zika exposure
Avoid for 28 days if exposed
Avoid for 6 months if infected
Listeria monocytogenes is a _____
Gram positive beta-haemolytic facultative anaerobe
Early onset neonatal listeriosis
Disseminated granulomas AKA granulomatosis infantisepticum
Listeriosis treatment
Ampicillin/penicillin G + gentamicin
Risk of fetal colonisation from chlamydia
50%
Prevalence of chlamydia in pregnancy
2-7%
Neonatal sequalae of chlamydia
Conjunctivitis
Pneumonia 20%
Treatment of covid
Steroids for 10/7 or until discharge if O2 requirement
VTE prophylaxis if admitted
Tocilizumab if CRP >75
Remdesivir if worsening symptoms despite Rx
