Pregnancy Rash Flashcards
Rash in pregnancy list
- Parvo B19
- Measles
- Rubella
- VZV
- HHV6
- HHV7
- Entero
- CMV
- EBV
- Covid-19
Syphilis
B19 in pregnancy risk
Features: minor febrile illness, erythema infectiosum, generalised rash, aplastic crisis, athropathy.
Highest risk: first 20 weeks - 9% risk of IUD.
3 to 11% risk of Hydrops between 9 to 20
Weeks with 50% mortality.
Seroprevalence: 60%
Measles in pregnancy risk
Features: Rash, Coryza, conjunctivitis, pneumonia, otitis, encephalitis.
Incubation: 7 to 21 days.
Infectious period: 4 days before to 4 days after rash.
Maternal morbidity due to pneumonia. Foetal risk LOW. Early SSPE.
VZV risk in pregnancy
The incubation period is 7 to 21 days. This can be prolonged if the patient is on steroids, immunosuppressed or has received VZIG.
Infectious period: 24 hours before the rash appears and until all the vesicles crust over.
The highest risk of maternal pneumonitis appears to be associated with maternal infection after 18 to 20 weeks of pregnancy. Encephalitis is a rare complication with mortality of 5 to 10%.
The risk of fetal varicella syndrome is estimated to be 0.4% < 12 weeks and nearly 2% when infection occurs between weeks 12 and 20 weeks.
Babies born to those infected with chickenpox late in pregnancy (20 to 37 weeks) may develop shingles of infancy or early childhood (0.8 to 1.7% risk in first 2 years of life) (33). This is thought to be due to reactivation of virus after a primary infection in utero.
Fetuses exposed to maternal chickenpox 7 to 20 days before delivery may develop neonatal chickenpox but this is usually less severe as transplacentally transmitted antibodies partially protect the fetus by this stage. If the mother develops a chickenpox rash between 7 days before and 7 days after delivery, the neonate may develop a severe disseminated haemorrhagic neonatal chickenpox known as purpura fulminans
Rubella risk in pregnancy
The risk to the fetus of primary rubella in the first 16 weeks gestation is substantial, with major and varied congenital abnormalities being associated with infection in the first trimester. 85%!!!
deafness, cataracts, heart defects, brain disorders, mental retardation, bone alterations, liver and spleen damage.
Rubella infection between 16 and 20 weeks gestation is associated with a minimal risk of deafness only.
Before date of conception or > 20 weeks carries no documented risk
A rubella reinfection is defined as rubella infection in someone who has previously had either documented natural rubella virus infection or successful rubella immunisation (41). Maternal reinfection is usually subclinical and diagnosed by changes in antibody concentration (IgG and/or IgM) only. The risk to the fetus of subclinical maternal reinfection in the first 16 weeks gestation has not been precisely determined, but an overview would suggest the risk of congenital damage is less than 10%, and probably less than 5%
Enterovirus in pregnancy
Vertical transmission has been documented in pregnancy. Whilst infection with coxsackie virus during pregnancy has been associated with early onset neonatal hepatitis (44, 45, 46), congenital myocarditis (44, 48 to 52), early onset childhood insulin dependent diabetes mellitus (47), abortion or intrauterine death (53), there is no clear causal relationship
HFMD - no risk
Booking blood stored how long and what tested?
Ideally done at 10 weeks
2 years
HIV, Hep B, syphilis
B19 testing in pregnancy
recent parvovirus B19 infection can be confirmed or excluded by testing for parvovirus B19 specific IgM on the first serum obtained from the day after rash onset.
Failure to detect parvovirus B19 specific IgM excludes infection in the 4 weeks prior to collection of the serum. Hence infection cannot be excluded if investigation commences more than 4 weeks after onset of rash illness
If parvovirus B19 IgM is detected in the first 20 weeks of pregnancy, confirmation is recommended by alternative assay, for example detection of high levels of B19V DNA or IgG seroconversion using an antenatal booking blood (58). Testing a second sample may demonstrate a change in IgM reactivity and provide an additional confirmation method.
B19 management in pregnancy
The management of proven parvovirus B19 infection has become more active with the demonstration that intrauterine transfusion of the fetus improves the outcome (59, 60, 8). On diagnosis of parvovirus B19 infection, specialist advice should be sought including the need for serial ultrasound scanning and Doppler assessment to prevent the progression of hydrops fetalis.
Laboratory investigation of hydrops fetalis
In a pregnant woman presenting with hydrops fetalis without a rash history, the diagnosis of recent parvovirus B19 infection may be achieved by testing an acute sample for B19V-specific IgM or B19V viral load (58), or by testing the antenatal booking sample in parallel with the sample at presentation for parvovirus-specific IgG to show seroconversion. Inability to detect B19V-specific IgG in maternal blood at the time of hydrops excludes B19V as the aetiological agent. Parvovirus B19 infection as the cause of hydrops fetalis can be confirmed by detection of B19V DNA in amniotic fluid or fetal blood if available.
Measles in pregnancy testing & management
A serum sample should be collected at first presentation and sent for laboratory testing for measles-specific IgM and IgG. Oral fluid should be collected at the same time, via the local Health Protection Team, for confirmation of the diagnosis by detection of viral RNA.
Recent measles infection can be confirmed or excluded by testing for measles-specific IgM on serum sample taken more than 4 days but within one month after the onset of rash.
Mum: observe
Neonate: Human normal immunoglobulin (HNIG) is recommended for neonates born to mothers who develop a measles rash 6 days before to 6 days after delivery. For neonates and infants exposed to measles, HNIG is recommended for up to and including 8 months of age.
Rubella in pregnancy testing & management
A serum at first presentation must be collected and sent for laboratory testing. Booking sera or other earlier serum samples may be available and may also aid in the diagnosis but the initial investigation should not be delayed. It is recommended that the laboratory investigates all cases of possible rubella by simultaneous testing for rubella-specific IgG (or total rubella antibody) and IgM.
Although positive rubella IgM results which do not reflect recent rubella (primary or reinfection) (‘false positive’) are infrequent, the control of rubella in the UK means that most rubella-specific IgM positive results do not reflect recent rubella. No pregnant woman should have rubella diagnosed on the basis of a single positive rubella-specific IgM alone. Results must be interpreted in relation to full clinical and epidemiological information. All rubella IgM-positive cases should be followed up by requesting a second sample and forwarding all samples to the UKHSA Virus Reference Department for confirmation. Confirmatory testing includes testing for rubella IgM with 2 different formats of assay, PCR testing for rubella RNA and/or rubella IgG avidity testing.
No specific treatment for mum.
Neonates born to women with confirmed rubella infection in pregnancy or where rubella infection could not be ruled out during pregnancy, should be investigated at birth for congenital infection. Samples of cord blood, placenta, urine and an oral fluid should be taken from the infant soon after delivery and sent to the UKHSA Virus Reference Department. Congenital rubella infection (CRI) is confirmed by detection of rubella IgM in serum or oral fluid and/or detection of rubella RNA in body fluids
Infants with congenital rubella infection are infectious. They excrete virus at birth and some may continue to excrete for more than a year. During the ante-natal period the health protection team should liaise with the hospital infection control team where the mother is booked and ensure there is an appropriate isolation plan for the neonate during and after birth. For infants diagnosed with CRI, isolation should be put in place for any subsequent healthcare attendance until the infant in no longer considered infectious.
VZV testing and management pregnancy
PCR
Detection of VZV DNA in the amniotic fluid by polymerase chain reaction (PCR) can also be used for the confirmation of chickenpox infection in the fetus. However, this is not routinely advised. The precise predictive value is unknown and the norms for viral load relating to fetal varicella syndrome are also unknown
Acyclovir in uncomplicated infections
Admit in severe
The time of onset of the rash is important for determining the likely effectiveness of antiviral treatment. Onset is timed from the first observable lesion. If the woman presents within 24 hours of the onset of the rash, she should be offered oral antiviral treatment for 7 days (for example, aciclovir 5 x 800mg per day)
If the woman presents more than 24 hours from the onset of rash and there are no indications of complications, antivirals are not routinely advised. There is no evidence that antivirals alter the natural history of uncomplicated chickenpox when given more than 24 hours after rash onset; however, this is a clinical decision
Intravenous treatment with aciclovir is indicated if the chickenpox is severe or there are any complications (66). Treatment of pneumonia associated with chickenpox in hospital is with intravenous aciclovir 3 x 10mg/kg/day for 5 to 10 days (67). Delivery by caesarean section may need to be considered.
There is a lack of evidence to support immunoglobulin and aciclovir treatment to prevent vertical transmission or fetal varicella syndrome
VZV testing and management pregnancy
PCR
Detection of VZV DNA in the amniotic fluid by polymerase chain reaction (PCR) can also be used for the confirmation of chickenpox infection in the fetus. However, this is not routinely advised. The precise predictive value is unknown and the norms for viral load relating to fetal varicella syndrome are also unknown
Acyclovir in uncomplicated infections
Admit in severe
The time of onset of the rash is important for determining the likely effectiveness of antiviral treatment. Onset is timed from the first observable lesion. If the woman presents within 24 hours of the onset of the rash, she should be offered oral antiviral treatment for 7 days (for example, aciclovir 5 x 800mg per day)
If the woman presents more than 24 hours from the onset of rash and there are no indications of complications, antivirals are not routinely advised. There is no evidence that antivirals alter the natural history of uncomplicated chickenpox when given more than 24 hours after rash onset; however, this is a clinical decision
Intravenous treatment with aciclovir is indicated if the chickenpox is severe or there are any complications (66). Treatment of pneumonia associated with chickenpox in hospital is with intravenous aciclovir 3 x 10mg/kg/day for 5 to 10 days (67). Delivery by caesarean section may need to be considered.
There is a lack of evidence to support immunoglobulin and aciclovir treatment to prevent vertical transmission or fetal varicella syndrome
VZV management in neonates
VZIG for neonates whose mothers develop chickenpox (but not shingles) in the period 7 days before to 7 days after delivery. VZIG can be given without VZV IgG antibody testing of the neonate or mother. Prophylactic, intravenous aciclovir should also be considered in addition to VZIG for neonates whose mothers develop chickenpox in the period 4 days before to 2 days after delivery, as they are at the highest risk of a fatal outcome despite VZIG prophylaxis.
VZIG is not usually required for neonates born more than 7 days after the onset of maternal chickenpox, or in those whose mothers develop shingles before or after delivery as these neonates will have maternal antibody.
VZIG is not indicated for neonates (under 7 days old) whose mothers have been exposed during pregnancy and have been found to be VZV IgG negative, unless the mother develops chickenpox. VZIG is only indicated for the neonate if they are directly exposed postnatally.
If severe chickenpox develops in the neonate despite VZIG, high dose intravenous aciclovir treatment of 20mg/kg every 8 hours for at least 7 days should be started ASAP
Mothers with chickenpox or shingles can breast feed safely. If they have lesions close to the nipple, they should express milk from the affected breast until the lesions have crusted. This expressed milk can be fed to the baby if he/she is covered by VZIG and/or aciclovir. started ASAP
Define contact to rash illness in pregnancy
being in the same room (example house or classroom or 2 to 4 bed hospital bay) for a significant period of time (15 minutes or more) or face-to-face contact. This definition is based on experience with VZV exposure.
