Infection in pregnancy Flashcards
clinical features of congenital herpes infection:
Features in the neonate may be local or disseminated.
Local features include vesicular lesions on the skin, eye or oral mucosa, without internal organ involvement.
Disseminated features include seizures, encephalitis, hepatitis or sepsis. Symptoms commonly appear in the first week of birth but manifestation can be as late as the fourth week of life.
when should HIV treatment (combined antiretroviral therapy) be started in pregnant women?
by 24 weeks gestation (& continue this lifelong)
when can zidovudine monotherapy be started in pregnant women?
CD4 count >350 and viral load of <10000 copies/ml (starting in 2nd trimester) & agrees to C-section
A 27-year-old female, gravida 2, para 1, presents to the antenatal clinic for a routine check-up. She is currently 36 weeks’ pregnant and reports feeling well throughout with no acute symptoms. Her past medical history is unremarkable, but she is allergic to penicillin.
Urinalysis demonstrates ++ for leukocytes and ++ for nitrites.
What is the next best step in managing this patient?
A. 7-day course of trimethoprim
B. 7-day course of cefalexin
C. 10-day course of nitrofurantoin
D. 10-day course of co-amoxiclav
E. Send home and review again in 1 week
A. 7-day course of trimethoprim
Trimethoprim is safe to be used in third trimester but should not be used in the first trimester due to the risk of congenital malformation, such as neural tube defects.
Not C: 10 day course of nitrofurantoin
Nitrofurantoin is avoided in near-term pregnancy due to the risk of neonatal haemolysis.
Not B: 7-day course of cefalexin
Cefalexin is less likely to be given, as the patient is penicillin allergic. There is up to 10% cross-sensitivity between penicillin and first-generation cephalosporins (ie. cefalexin).
Not D: 10-day course of co-amoxiclav
The patient is penicllin allergic, therefore co-amoxiclav should be avoided.
Not E: Send home and reassure
Asymptomatic bacteriuria in pregnancy must be treated. If it is left untreated, it can lead to acute pyelonephritis or preterm labour.
Antibiotic management options of UTIs in pregnancy:
Urinary tract infection in pregnancy requires 7 days of antibiotics.
The antibiotic options are:
- Nitrofurantoin (avoid in the third trimester)
- Amoxicillin (only after sensitivities are known)
- Cefalexin
Nitrofurantoin needs to be avoided in the 3rd trimester as there is a risk of neonatal haemolysis (destruction of the neonatal red blood cells).
Trimethoprim needs to be avoided in the 1st trimester as it is works as a folate antagonist. Folate is important in early pregnancy for the normal development of the fetus. Trimethoprim in early pregnancy can cause congenital malformations, particularly neural tube defects (i.e. spina bifida). It is not known to be harmful later in pregnancy, but is generally avoided unless necessary.
Antibiotic management options of UTIs in pregnancy:
Urinary tract infection in pregnancy requires 7 days of antibiotics.
The antibiotic options are:
- Nitrofurantoin (avoid in the third trimester)
- Amoxicillin (only after sensitivities are known)
- Cefalexin
Nitrofurantoin needs to be avoided in the 3rd trimester as there is a risk of neonatal haemolysis (destruction of the neonatal red blood cells).
Trimethoprim needs to be avoided in the 1st trimester as it is works as a folate antagonist. Folate is important in early pregnancy for the normal development of the fetus. Trimethoprim in early pregnancy can cause congenital malformations, particularly neural tube defects (i.e. spina bifida). It is not known to be harmful later in pregnancy, but is generally avoided unless necessary.
Causes of UTI in pregnancy:
Most common cause of urinary tract infection is Escherichia coli (E. coli). This is a gram-negative, anaerobic, rod-shaped bacteria that is part of the normal lower intestinal microbiome. It is found in faeces, and can easily spread to the bladder.
Other causes:
- Klebsiella pneumoniae (gram-negative anaerobic rod)
- Enterococcus
- Pseudomonas aeruginosa
- Staphylococcus saprophyticus
- Candida albicans (fungal)
urine dipstick results for UTI in pregnancy:
Nitrites are produced by gram-negative bacteria (such as E. coli). These bacteria break down nitrates, a normal waste product in urine, into nitrites. The nitrites in the urine suggest the presence of bacteria.
Leukocytes refer to white blood cells. There are normally a small number of leukocytes in the urine, but a significant rise can be the result of an infection, or alternative cause of inflammation. Urine dipstick tests examine for leukocyte esterase, a product of leukocytes, which gives an indication to the number of leukocytes in the urine.
Nitrites are a more accurate indication of infection than leukocytes.
During pregnancy, midstream urine (MSU) samples are routinely sent to the microbiology lab to be cultured and to have sensitivity testing.
presentation of UTI in pregnancy:
Lower urinary tract infections present with:
-Dysuria (pain, stinging or burning when passing urine)
-Suprapubic pain or discomfort
-Increased frequency of urination
-Urgency
-Incontinence
-Haematuria
Pyelonephritis presents with:
-Fever (more prominent than in lower urinary tract infections)
-Loin, suprapubic or back pain (this may be bilateral or unilateral)
-Looking and feeling generally unwell
-Vomiting
-Loss of appetite
-Haematuria
-Renal angle tenderness on examination
A 25 year old woman delivers her first baby vaginally in the birth centre at 37 weeks gestation. On examination, the newborn has chorioretinitis, hearing impairment and hydrocephalus. She is also suffering from frequent seizures. On questioning, the mother remembers having a flu-like episode early in the pregnancy but this resolved quickly so she did not seek medical advice.
What is the most likely causative organism for this newborn’s features?
A. Treponema Pallidum
B. Toxoplasma Gondii
C. Listeria Monocytogenes
D. Varicella zoster virus
E. Group B Streptococcus
B. Toxoplasma Gondii
Toxoplasma Gondii is the most likely organism. It is a parasite commonly found in cat faeces or contaminated food products. Infected mothers may be asymptomatic or have mild flu-like symptoms. Early infection with toxoplasma can lead to congenital toxoplasmosis, a severe condition typically presenting with hydrocephalus, seizures, visual and hearing impairment
Not A: Treponema Pallidum
Treponema Pallidum is the organism responsible for syphilis. Congenital syphilis commonly presents with keratitis, malformed teeth and sensorineural deafness
Not C: Listeria monocytogenes
Listeria Monocytogenes is commonly contracted during pregnancy through the consumption of unpasteurised dairy products. Maternal infection with listeria is a recognised cause of early onset neonatal sepsis
Not D: VZV
Varicella zoster virus causes congenital varicella syndrome which typically presents with limb hypoplasia, skin scarring and eye defects
Not B: GBS
Group B Streptococcus infection in the neonate can cause bacterial sepsis, meningitis or pneumonia in the early neonatal period
what are features of toxoplasmosis/investigations/complications/management:
Toxoplasmosis infection in pregnancy can lead to miscarriage, neonatal death, premature labour, low birthweight.
Many infected infants are asymptomatic, however may go on to develop symptoms later in life such as:
- CNS problems such as cerebral palsy, epilepsy and hydrocephalus
- learning disability
- visual impairment
- hearing loss
Diagnosis
1. Antenatal ultrasound to look for foetal abnormalities
2. Amniocentesis with PCR testing
3. Maternal IgM testing can be used to check for previous exposure
4. Foetal blood test
Management
The antibiotic spiramycin is used to treat toxoplasmosis during pregnancy and is thought to reduce transmission to the baby.
A 30-year-old female, gravida 2, para 1, is admitted for a planned caesarean section delivery at 38 weeks of pregnancy. Her pregnancy history is unremarkable, except that she is a known GBS carrier. She was offered intrapartum antibiotic during her previous vaginal delivery.
Which of the following managements is the most appropriate for this patient regarding her GBS status?
A. Intrapartum benzylpenicillin
B. Intrapartum erythromycin
C. No intrapartum antibiotics
D. Postpartum erythromycin for 7 days
E. Postpartum benzylpenicillin for 7 days
C. No intrapartum antibiotics
This patient is a known GBS carrier who is having a planned caesarean section. Intrapartum antibiotics are not required in those undergoing a caesarean section, unless labour is complicated by preterm or prolonged spontaneous rupture of membrane.
Intrapartum antibiotics only for spontaneous vaginal delivery.
RFs for GBS:
Risk factors for neonatal GBS infection include:
- Positive GBS culture in current or previous pregnancy
- Previous birth resulting in neonatal GBS infection
- Pre-term labour
- Prolonged rupture of membranes (>18 hours)
- Intrapartum fever >38 degrees Celsius
- Chorioamnionitis
what bacteria causes GBS (gram stain and morphology?
Group B Streptococcus (GBS) infection is due to the bacterium streptococcus agalactiae.
a gram-positive coccus (round bacterium) with a tendency to form chains (as reflected by the genus name Streptococcus). It is a beta-hemolytic, catalase-negative, and facultative anaerobe
epidimiology of GBS
Most commonly GBS is carried as an asymptomatic commensal bacterium in the gastrointestinal and genitourinary tracts. It is estimated that approximately 25% of pregnant women are carriers.
In some cases, GBS can cause severe illness in the mother and infant due to transmission during delivery.
what is lochia? types?
Lochia is vaginal discharge after childbirth. It consists of blood, mucus, uterine tissue and other materials from your uterus.
1. lochia rubra
2. lochia serosa
3. lochia alba
