Fetal Disorders and Anomalies w/out Genetics Flashcards
How do you define alloimmunization?
Immune response to foreign antigens from another human
What is an indirect Coomb’s test?
Antibody screen in serum
What are possible sources of allommunization to the D antigen group?
Prior fetus with Rh+ antigen
Prior blood transfusion
What red cell antigens comprise the Rh antigen group?
C c D E e
What is Du antigen, and do you give rhogam?
Weak D antigen, yes we still give rhogam
What are the fetal risks in an alloimmunized pregnancy?
fetal anemia
hydrops
death
erythroblastosis fetalis
What is the cause of fetal anemia in an alloimmunized pregnancy?
Antibodies against fetal antigen that are destroying fetal RBCs
What is hemolytic disease of the newborn?
Hemolysis and anemia in the fetus due to Fetal RBC distruction by maternal alloantibodies that have crossed into the fetal circulation
When a positive antibody screen is identified, what are the next steps in your evaluation of the patient?
History to see if exposed
Paternal testing to assess risk
Fetal testing to assess risk
Serial titers until critical titer is reached (every 4 weeks)
MCA Dopplers once critical titer is reached
What is the mode of inheritance of red cell antigens?
Autosomal dominant for Rh
Co-dominant for ABO
When do RBC antigens first appear?
38 days
How likely is a Rh negative woman to get sensitized without rhogam?
What if she gets Rhogam postpartum?
What if she gets Rhogam at 28 weeks and postpartum?
16%
- 6%
- 16%
How much blood exposure does one 300mcg Rhogam protect you from?
30mL
What is a Kleihauer betke?
Maternal blood in acid elution, moms cells destroyed by Acid, HbF identified with stain.
Calculate % of fetal cells to maternal cells. Mutiply by 50, divide by 30 and thats how many vials of rhogam to give
If the father of the baby is homozygous for red cell antigen of interest, what is the likelhood of the fetus being at risk for hemolytic disease of the newborn?
What if the father is heterozygous?
Homozygous: 100%
Heterozygous: 50%
How can you determine fetal red cell antigen status?
Cell free DNA, Amniocentesis
If the fetal red cell antigen status is unknown, how will you follow the patient if this is her first alloimmunized pregnancy?
Can do paternal antigen testing, if negative and paternity is 100%
No further testing
If paternal testing is positive then monthly titers until she reaches critical titer
If the fetal red cell antigen status is unknown, how will you follow the patient if this is a subsequent alloimmunized pregnancy?
In a previously affected fetus, just skip to MCA Dopplers every 1-2 weeks starting at 16-18 weeks.
What is the role of antibody titers in a first alloimmunized pregnancy?
First alloimmunuzed pregnancy: Assess for a critical titer and the need for MCA testing for anemia
Subsequent alloimmunuzed pregnancy: No role for titers
What do you consider to be a critical antibody titer?
1:16 or higher
Once a critical antibody titer is identified, how does your management change?
Start MCA Doppler velocimetry weekly assessing for anemia and also evaluating for fetal hydrops
How do MCA Dopplers identify anemia?
As anemia worsensblood is less viscous and gets shunted to brain
Net result is an increased in the velocity of flow in MCA
Describe how you perform an MCA Doppler PSV assessment?
MCA near its origin Side closer to probe No fetal movement / breathing Zero angle of approach (no angle correction) Circle of willis visible 3 measurements, use the highest value
What does an MCA PSV >1.5MoM indicate?
Suggestive of fetal anemia
How do you manage the patient if an MCA PSV >1.5 at 20 weeks?
PUBS
How do you manage the patient if an MCA PSV >1.5 at 30 weeks?
PUBS
When do you deliver if MCA is >1.5?
When do you deliver if MCA is <1.5?
> 1.5: 35 weeks
<1.5: 37-38w6d
What are the risks of fetal blood sampling?
Fetal loss (1-2%)
Bradycardia
Rupture of membranes
Infection
At what Hematocrit cutoff do you transfuse?
<30%
Describe how a fetal blood sampling is performed?
Placental umbilical cord insertion preferred.
Use umbilical vein to decrease the risk of fetal bradycardia.
Don’t transfuse if hematocrit is greater than 30%.
Goal HCT is between 35-40%
What kind of blood is transfused?
Fresh, leukoreduced, O negative, washed, CMV negative, irradiated blood
At what fetal Hb does hydrops usually occur?
<5g/dL
When do you recommend delivery in an alloimmunized patient in her first alloimmunized pregnancy who has not reached critical titers?
39 weeks
When do you recommend delivery in an alloimmunized patient in her first alloimmunized pregnancy who has received a fetal transfusion?
Transfuse up to 35 weeks and deliver at 37-38 weeks
Which non D red cell antigens are not associated with hemolytic disease of the newborn?
Lewis and Lutheran
What are possible sources of allommunization to the kell antigen?
Blood transfusion, paternal antigen from prior pregnancy
Why does the kell antigen cause greater risks for fetal anemia?
It attacks erythroid progenitor cells in bone marrow
When a positive antibody screen of non D antibodies is identified, what are the next steps in your evaluation of the patient?
See if they are associated with hemolytic disease of the fetus and if they are get paternal antigen testing
If the fetal red cell (non-D) antigen status is unknown, how will you follow the patient if this is her first alloimmunized pregnancy?
What if it’s a subsequent alloimmunuzed pregnancy
First alloimmunized pregnancy:
Titers q 4 weeks
Unles it’s Kell in which case I skip to MCA Dopplers q 1-2 weeks
Subsequent alloimmunized pregnancy:
Skip to MCA Dopplers q 1-2 weeks starting at 16-18 weeks
What do you consider to be a critical kell antibody titer?
Any titer as Kell isoimmunization at even low titers has been associated with hemolytic disease
How does management of a kell alloimmunized pregnancy differ from management of other non-D red cell antibodies associated with hemolytic disease of the newborn?
No need for titers as Kell isoimmunization at even low titers has been associated with hemolytic disease
What is FNAIT?
How do these fetuses present?
Fetal/Neonatal Alloimmune Thrombocytopenia
Maternal antigens against fetal platelets
Platelet count < 100,000 at birth or 7 days from birth
OR
Fetal intracranial hemorrhage in the absence of other causes
What are the fetal risks of FNAIT?
Fetal intracranial hemorrhage
What patients are candidates for a workup of possible FNAIT?
History of a prior fetus with ICH or thrombocytopenia <100k in first 7 days of life
What questions / labs should you ask/perform in a history of a baby with thrombocytopenia to assess whether a NAIT workup is necessary?
Maternal platelet count
US findings during that pregnancy (brain bleed)
Sister with a history of a child with NAIT
Is this the same partner as prior pregnancy?
When working up a patient for FNAIT, what workup do you perform?
Platelet antigen testing (Look for maternal/paternal incompatibility)
Then test for antibodies
What are the most common platelet antigens involved with FNAIT?
HPA1a (mom HPA-1a homozygous negative, dad HPA-1a homozygous or heterozygous)
HPA-5b less common
HPA-4 in asians
What % of FNAIT is cuased by HPA-1a platelet antigen?
85%
You perform HPA-1a/b platelet antigen testing on both parents. Results are as follows: Mom negative for HPA-1a/b antigens, Dad positive for HPA-1a antigen, negative for HPA-1b antigen. How do you interpret these results? Based on these results, what is the next step in your evaluation?
Mom is negative for the platelet antigen and dad positive, this means that there is a risk of NAIT.
Next step is testing for HPA-1a antibodies in the mom.
You order maternal platelet antibody testing. The patient returns positive for HPA-1a antibodies. You perform genotype testing and determine the mother is homzygous HPA-1b/1b and father is homozygous HPA-1a/1a. Base on these results, what are the risks to this fetus? Will you offer this patient treatment? If so, what?
Mom is negative for the platelet antigen and dad positive
Mom also has anti HPA-1a antibodies, this fetus is at risk
Would treat.
How do you treat a patient with a prior affected child with NAIT but no fetal/neonatal ICH?
What if they had a prior ICH?
No Prior ICH:
20 weeks: weekly IVIG and steroids
U/s q 4-6 weeks looking for ICH
C/s at 37-38 weeks
Prior ICH: 12 weeks weekly IVIG 20 weeks: weekly IVIG and steroids Delivery by c/s at 37-38 weeks unless prior ich was <28 weeks then 36-37weeks
How do you manage the delivery in a patient with FNAIT?
Who would you not offer vaginal delivery?
Cesarean section
if platelet count is >100,000 at 32 weeks pubs, can consider vaginal delivery.
No vaginal delivery if prior ICH was before 28 weeks
What percentage of FNAIT pregnanies will be complicated by fetal intracranial hemorrhage?
What percentage of fetal intracranial hemorrhages associated with FNAIT occur in the first pregnancy?
7-25%
63%
When do the majority of fetal intracranial hemorrhages related to FNAIT occur?
After 20 weeks
What is the recurrence rate of FNAIT?
80-90% recurrence of ICH, and happens earlier in future pregnancies
How do you define Non-immune Hydrops?
Excessive fluid in 2+ compartments (ascites, pericardial, pleural, skin edema)
Without maternal alloimmunization
How do you counsel a patient about the finding of Non-immune Hydrops in the first trimester?
Discuss possible etiologies and workup
Poor prognosis when found in first trimester
Offer termination
How do you counsel a patient about the finding of Non-immune Hydrops in the second trimester?
Discuss possible etiologies and workup
Treatment if cause is reversible (I.e. fetal anemia due to parvovirus)
How do you counsel a patient about the finding of Non-immune Hydrops in the third trimester?
Maternal and fetal work-up.
<34 weeks: Treatment if cause is reversible (I.e. fetal anemia due to parvovirus)
>34 weeks: Deliver
What is your differential diagnosis for causes of Non-immune Hydrops?
Fetal anemia Infectious Genetic Structural abnormality Arrhythmia Chorioangioma Inborn errors of metabolism
What workup do you perform if Hydrops is identified?
H&P (Recent illness, family history) Detailed ultrasound (anomalies, arrhythmia) Fetal echo MCA Doppler velocimetry Amniocentesis (microarray and infectious studies) Indirect coombs CBC / MCV (Thalassemias) CMV/Toxo/Parvovirus IgG/Igm
How do you manage a patient with Non-immune Hydrops diagnosed at 12 weeks?
Assess cause and possibility for treatment; otherwise, discuss termination
How do you manage a patient with Non-immune Hydrops diagnosed at 24 weeks?
Assess for cause. Assess for treatment possibility.
Arrhythmia - administer anti arrhythmic medication
Anemia - IUT
Hydrothorax - needle drainage
CPAM - if macro cystic needle drainage, if microcytic steroids
TTTS/TAPS - laser photocoagulation
Administer betamethasone (shared decision making model); however, discuss significant risk of neonatal demise in the setting of hydrops and prematurity.
Ultrasound findings in a sacrococcygeal teratoma?
Mass coming off of sacrum of fetus
Mixed solic/cystic components
Differential diagnosis for sacroccocygeal teratoma?
Myelomeningocele
Additional workup for sacrococcygeal teratoma?
Detailed U/s TFR (tumor volume to fetal weight ratio) Assess for vascularity (increased vascularity -> shunting -> High output heart failure -> hydrops) Echo Fetal MRI
Prognosis for sacrococcygeal teratoma?
When TFR > 0.12 before 24 weeks, poor prognosis
Diagnosed in fetal life have 30-50% mortality
Universally fatal once hydrops present
Improved outcomes with cystic tumors
Clinical considerations for sacrococcygeal teratoma?
Monitor for polyhydramnios
Cesarean preferred for tumor >5cm (risk of rupture)
Watch for signs of cardiovascular compromise / increased tumor size
Resect after delivery
Condition where Neuropore fails to close posteriorly vs anteriorly?
Posteriorly, spina bifida
Anteriorly, anencephaly
What are risk factors for NTD?
Prior affected child
Medication use (carbamezapine, valproic acid)
Maternal hyperthermia (1st trimester fever, hot tub, sauna)
Diabetes
Obesity
Describe US findings of fetal NTD?
1) Lemon sign - Scalloped frontol bones
2) Banana sign - cerebellar compression and obliteration of cisterna magna (Chairi II malformation)
3) Ventriculomegaly
4) Neural sac
Differential diagnosis for NTD?
Body stalk anomaly
Sacrococcygeal teratoma
What is recurrence risk for NTD?
3-4% with one child affected
10% with two children affected
How effective is preconception folate in reducing risk of NTD?
50-70%
If a lumbosacral NTD is identified on a mid-trimester US, how do you counsel the patient?
Tell about risks to fetus (Increased risk of: Seizures Bladder / bowel dysfunction Inability to walk Need for shunt
In utero surgery
vs postnatal surgery.
Vs termination
If a lumbosacral NTD is identified on a mid-trimester US, what workup do you do?
Amniocentesis
Detailed U/S
Fetal MRI
Pediatric neurosurgery consultation
What do you send on an amniocentesis
Microarray / Karyotype
AFP
Acetylcholinesterase
What genetic conditions are associated with NTD?
Trisomy 13 / 18
What is the likelihood of identifying an underlying karyotype abnormality in fetus with a NTD?
4%
What features determine prognosis?
Level (higher is worse)
Size (larger is worse)
Which patients may be considered candidates for in utero repair of a fetal NTD?
>18yo 19w0d-25w6d Normal karyotype S1 level or higher Confirmed Arnold-Chiari II malformation on prenatal US and MRI
How do you counsel a patient regarding the risks of in utero repair of NTD?
Preterm birth
Oligohydramnios
Maternal uterine rupture in a subsequent pregnancy
How do you counsel a patient regarding the benefits of in utero repair of NTD?
Decreased need for shunts
Reduced motor / sensory in lower extremities
Ambulatory improvement at 30 months
Decreased cerebellar herniation
When do you recommend delivery following in utero repair of an NTD?
36w0d-37w0d
Do you recommend C/s or Vaginal delivery following in utero repair of NTD?
C/s for open repair due to increased risk of uterine rupture
What is the likelihood of uterine rupture in labor following in utero repair of a NTD?
35% risk of dehiscence or thinning
Differential diagnosis for Anencephaly?
Amniotic band syndrome
Severe microcephaly
Encephalocele
What are the ultrasound findings in anencephaly?
Absence of calvarium
Proptosis, with no neural tissue above orbits (frog sign)
Flattened head shape
Acrania/exencephaly (when seen in 1st trimester)
How do you counsel a patient with anencephaly?
Risk of recurrence?
Lethal malformation (offer termination) 2-5% risk of recurrence (reduced with folic acid)
What are the risk factors for anencephaly
Folic acid deficiency
Diabetes
Obesity
Valproic acid / Carbamezapine
Findings of alobar holoprosencephaly?
Absent butterfly sign (choroid plexus in 1st trimester) Fused thalami Monoventricle ACC Cyclopia Facial anomalies
What evaluation do you offer for alobar holoprosencephaly?
Amniocentesis
Offer termination
What genetic conditions are assoicated with Alobar holoprosencephaly?
T13 (25-50%) Smith-Lemli Opitz Meckel gruber Aicardi Velocardiofacial
What is the prognosis for alobar holoprosencephaly?
50% death at <5 months (80% in <1 year)
Hypotonia
Feeding difficulties
Seizures
What are the US findings in Semiilobar holoprosencephaly?
Single ventricle
Fused frontal lobes (posterior fissure seen)
Partially fused thalami
ACC
What are the US finidngs in Lobar HPE?
Absent CSP
Inter hemispheric fissure seen
Fused fornices
SEPARATE thalami
If you dont see a kidney in the renal fossa, what is your differential diagnosis?
Pelvic kidney
Unilateral renal agenesis
Next step in seeing a suspected unilateral renal agenesis or pelvic kidney?
H&P
Detailed US
Follow throughout pregnancy to assess for blockage / AFI
Prognosis for unilateral renal agenesis and pelvic kidney?
Usually has good prognosis as long as contralateral kidney functions well
Prognosis for bilateral renal agenesis?
Lethal (pulmonary hypoplasia)
What is your differential diagnosis for cystic appearing kidney?
Urinary tract obstruction
Obstructive cystic dysplasia
Autosomal recessive polycystic kidney
Autosomal dominant polycystic kidney (less likely in utero)
What is the prognosis for multicystic dysplastic kidney?
unilateral: favorable outcomes
bilateral: much worse prognosis due to oligohydramnios and pulmonary hypoplasia
How do you work up a patient with MCDK?
H&P
Offer invasive testing (increased risk of CNV on microarray)
Even higher risk of genetic abnormality if bilateral
Syndrome that can have MCDK?
What are the other findings in it?
Meckel gruber (enlarged cystic kidney, encephalocele, polydactyly)
What are the findings in ARPKD?
Enlarged, echogenic kidneys
Oligohydramnios
What is the prognosis in ARPKD?
Variable, but usually poor outcomes when diagnosed prenatally due to oligohydramnios and pulmonary hypoplasia
What is meckel gruber syndrome?
Enlarged kidney with fluid filled cysts
Occipital encephalocele
Polydactyly
Prognosis in meckel gruber syndrome?
most die in infancy due to Renal failure or respiratory problems
Differential diagnosis for ambiguous genitalia (now disorder of sexual development)?
46XX: Congenital adrenal hyperplasia (21 hydroxylase, 11b hydroxylase, 3B hydroxysteroid dehydrogenase) SRY translocation 46XY: Androgen insensitivity Leydig cell hypoplasia SLOS, Campomelic dysplasia
How do you counsel a patient regarding disorder of sexual development?
Unable to determine by ultrasound the sex of the baby
Can be due to image artifacts or developmental patholgogies
We can assess better by doing more imaging, and genetic testing
Approach to ambiguous genitalia?
Detailed US
Invasive testing (or cell free DNA if declines)
Test for Karyotype, Microarray, FISH for X Y and SRY
7 Dehydroxycholesterol (In SLOS)
21 Hydroxylase gene (CAH)
Fetal MRI to look for uterus, ovaries
Postnatal follow up of Disorders of sexual development?
Rule out life-threatening processes (salt wasting in CAH)
Determine sex for rearing/identity
Plan for normal pubertal development and fertility
Assess for undescended testes
If you have ambiguous genitalia and cfDNA is 46XX, what would be at the top of your D/Dx?
CAH (21 hydroxylase deficiency)
How is 21 hydroxylase deficiency inherited?
Autosomal recessive
If patient had a history of a child with CAH (21 hydroxylase def), what can they do for a future pregnancy?
Preimplantation genetic testing
Research into Dexamethasone treatment for first 9-10 weeks of development and if fetus ends up being genetic male, can discontinue at 9-10 weeks. (possible cognitive delay in some studies, hence research)
If you have ambiguous genitalia and FGR, and amniocentesis shows increase in 7dehydroxycholesterol (7DHC), what disorder is most likely?
Smith-Lemli-Optiz
What are the features and prognosis of SLOS?
Polydactyly/Syndactyly Ambiguous genitalia Upturned nose / V-shaped Mouth CNS abnormalities Prognosis: Guarded, severe developmental/intellectual disabilities
What are the differential diagnoses for echogenic bowel?
Aneuploidy CF (meconium ileus / peritonitis) Bleed Fetal growth restriction Infection (CMV, toxo, parvo, varicella) 80%+ normal variant
How would you evaluate echogenic bowel?
CF testing Aneuploidy screening CMV/Toxo/parvo testing Growth ultrasound Detailed U/s
What can cause false positive for echogenic bowel?
Using high frequency transducer
Differential diagnosis for omphalocele?
Omphalocele
Gastroschisis
Umbilical cord cyst
Body stalk anomaly
What is an omphalocele?
A midline abdominal wall defect (absent skin, fascia, abdominal muscles) of variable size at the base of the umbilical cord.
Describe the US characteristics of an omphalocele?
Umbilical cord insertion into the membrane covering the contents of the viscera extruding from abdominal wall defect
How do you distinguish between an omphalocele and gastroschisis on US?
Omphalocele: Midline, covered by membrane
Gastroschisis: paramedial (usually right), not covered by membranes, elevated MSAFP
How do you counsel a patient if an omphalocele is identified on US?
Increased risk of genetic abnormality, and other defects (Detailed US and echo)
Increased risk of pulmonary hypertension (which can lead to infant death)
What is the likelihood of an underlying genetic abnormality in the presence of an omphalocele?
Up to 50%
How does the size of an omphalocele impact the likelhood of an underlying genetic abnormality?
The smaller the size, the more likely it is a genetic abnormality
How do you counsel a patient about prognosis for fetuses with an omphalocele?
Depends on whether genetic disorders are with it or not
Liver in or out (Liver out = poor prognosis)
What workup/follow up do you recommend when an omphalocele is identified on ultrasound?
H&P
Detailed U/s including echocardiogram) looking for other features (T18 features, cardiac anomalies 36%,macroglossia, renal abnormality in beckwith)
Invasive testing - Karyotype/microarray, Beckwith wiedemann
Serial growth ultrasounds
Surgery and NICU consult
What are the most likely genetic conditions associated with an omphalocele?
Trisomy 18
Trisomy 13
Beckwith Wiedemann
How do you counsel a patient regarding route of delivery in the setting of omphalocele without an underlying genetic abnormality?
Vaginal delivery, reserve C/s for the usual obstetric indications
Though c/s may be recommended in giant omphalocle (>75 percent of the liver is extracorporeal
What is a gastroschisis?
Gastroschisis is a full-thickness paraumbilical abdominal wall defect usually associated with evisceration of bowel
What are risk factors for gastroschisis?
Young mothers
Smokers
How does gastroschisis occur?
Abnormal involution or vascular damage to the omphalomesentary artery or right umbilical vein
Describe the US characteristics of gastroschisis.
Multiple loops of bowel floating freely in the amniotic fluid (cauliflower appearance)
How do you counsel a patient if gastroschisis is identified on US?
85% occur in isolation, not associated with genetic syndromes
Increased risk of IUGR
Increased risk of PTB
Increased risk of fetal /neonatal death
What additional workup/follow up do you perform if gastroschisis is identified on ultrasound?
Detailed anatomic survey Serial growth ultrasound Fetal echocardiogram Antenatal testing at 32 weeks Pediatric surgery consultation Antenatal NICU consultation
What is the likelihood of associated anomalies if gastroschisis is identified on US?
15%
What is the likelihood of an underlying genetic abnormality in isolated gastroschisis?
Uncommon
What is your differential diagnosis for an elevated MSAFP?
Wrong gestational age Twin pregnancy Gastroschisis/omphalocele Open neural tube defect Placental abnormality
What pregnancy complications may occur if fetal gastroschisis is identified?
IUFD
FGR
Bowel atresia (infarction /ischemia) - more likely with bowel dilation which is defined as size >7mm however 29% occur with size >14mm
Short gut syndrome (motility disorders)
When do you recommend fetuses with gastroschisis be delivered?
37-38 weeks
Do you recommend C/s or vaginal delivery for fetuses with gastroschisis?
Vaginal delivery
What is the recurrence risk for fetal gastroschisis?
4%
Lithium, fetal risks?
Ebsteins anomaly
Valproic acid / Carbamezapine, fetal risks?
NTDs
MTX, fetal risks?
Calvarium hypoplasia
Limb defects
Craniofacial abnormality
Describe the US findings of Tetralogy of fallot?
Pulmonary stenosis or or atresia
RVH (not usually seen in utero due to ductus arteriosus)
Overriding aorta
VSD (Perimembranous)
How do you counsel your patient if Tetralogy of fallot is suspected on ultrasound?
90% survival if isolated.
32% mortality at 4 years if absent pulmonary valve is noted.
What genetic conditions are associated with Tetralogy of fallot?
T13/T18/T21
22q11
CHARGE
VACTERL
What is the likelihood of associated anomalies in the setting of Tetralogy of fallot?
~50%
What additional evaluation do you perform if Tetralogy of fallot is identified?
Detailed anatomic survey Serial growth ultrasound Fetal echocardiogram (AVSD) Antenatal testing at 32 weeks Pediatric CT surgery consultation if blue is suspected Antenatal NICU consultation
Do you offer amniocentesis for fetuses with Tetralogy of fallot? Why or why not?
Yes increased risk of genetic abnormality
If you perform an amniocentesis for tetralogy of fallot, what do you send the amniotic fluid for?
FISH reflect to karyotype and to CMA, save cells for rarer disorders if negative
What is the likelihood of identifying a genetic condition or karyotype abnormality in a fetus with Tetralogy of fallot?
~50%
Describe the US findings of clubfoot?
Persistent Ability to see the plantar surface of the fetal foot in the same sagittal plane as both lower extremity bones
How do you counsel a patient if you identify a clubfoot on ultrasound?
2/3 are isolated
2% associated with aneuploidy
Prognosis depends on associated anomalies
Most grow up to wear normal shoes and live active lives, though they may need surgery and / or braces
What genetic counditions are associated with clubfoot?
T18
T13
Rarer genetic syndromes
What is the likelihood of associated anomalies in the setting of club foot?
1/3 have associated anomalies
What additional evaluation do you perform if a clubfoot is identified?
Detailed US
Fetal echo
Amnio if other findings noted
Do you offer amniocentesis for fetuses with a club foot? Why or why not?
I offer it, but tell them that it is unlikely to be positive if it is an isolated finding
If you perform an amniocentesis for club foot, what do you send the amniotic fluid for?
Karyotype / microarray
Other studies if suspicious for a genetic syndrome
What is the likelihood of identifying a genetic condition or karyotype abnormality in a fetus with clubfoot?
1-2%
Clubfoot recurrence risk?
3-5%, 25% if parent and a previous child had a clubfoot
Fetus with hitchhikers thumb, scoliosis, short limbs, clubbed feet, what is the most likely diagnosis?
Skeletal dysplasia - diastrophic dysplasia
- hitchhiker thumb
- cauliflower ear
- scoliosis
- cleft palate
G1P0 at 18 weeks with long bones lagging by 4 weeks, Humerus and femur appeared angled. Differential diagnosis?
Osteogenesis Imperfecta
Thanataphoric dysplasia
Campomelic dysplasia
Kyphomelic dysplasia
What further structures on imaging should you focus on to narrow your diagnosis of skeletal dysplasias?
Examine all extremities Look at bone mineralization Look at hands and feet (polydactyly, hitchhikers thumb-diastrophic dysplasia, trident hands-achondroplasia) Profile and head shape Spine curvature, hemivertabrae Clavicles (if missing, cleido-cranial dysplasia) Chest shape / ribs Ratios: Femur to foot length ratio Femur length to AC ratio Chest circumference / AC ratio
FL/Foot length ratio, cutoff and what it means?
<1 suggests skeletal dysplasia
FL/AC ratio, cutoff and what it means?
<0.16, suggests lethality
Chest circumference / AC ratio
<0.8 suggests lethality
US findings in campomelic dysplasia?
Prognosis
Short / bowed long bones
Narrow chest
Hypoplastic scapulas
Sex reversal
Lethal in first year of life
Describe the US findings associated with cleft lip and palate.
Cleft lip: Anechoic area at the level of the lips on on coronal imaging
Cleft palate: anechoic area at level of plaata in transverse view of the head
How do you counsel a patient if you identify a cleft lip and palate on US?
Baby may have difficulty feeding
Need surgical repair
Molding devices prior to repair
What genetic conditions are associated with cleft lip and palate?
In midline cleft: holoprosencephaly, T13, frontonasal dysplasia, treacher collins syndrome, median cleft face syndrome, etc…
How common is a cleft palate, when you have a cleft lip?
75% of the time
What is the likelhood of associated anomalies in the setting of cleft lip and palate?
Unilateral: 10%
Bilateral: 25%
What additional evaluation do you perform if a cleft lip and palate is identified?
Detailed US (other abnormalities, intracranial structures like CC or cerebellar vermis)
3D ultrasound
Genetic counseling
Amniocentesis
Fetal echo
Referral to plastics/maxillofacial surgery/NICU
Do you offer amniocentesis for fetuses with a cleft lip and palate? Why or why not?
Yes, increased risk of aneuploidy or abnornmal microarray
If you perform an amniocentesis for cleft lip and palate, what do you send the amniotic fluid for?
Microarray / Karyotype
Consider testing for single gene disorders if other findings are found not suggestive of common aneuploidies
What is the likelihood of identifying a genetic condition or karyotype abnormality in a fetus with cleft lip and palate?
3% associated with a syndrome
10% have abnormal microarray
Less likely to have issue if isolated
What pregnancy complications may occur if the fetus has a cleft lip and palate?
Polyhydramnios
Preterm contractions
Preterm birth
Airway difficulty
What is the significance of a midline facial cleft?
Increased risk of a genetic abnormality
example - treacher collins syndrome
What is the significance of a cleft palate without a cleft lip?
More likely to evade diagnosis
What are the concerns for micrognathia?
Airway issues at time of delivery,
Differential diagnosis for intracardiac echogenic mass?
Rhabdomyoma
Fibroma
Teratoma
Myxoma
What evaluation do you offer for intracardiac mass?
Fetal echo
Fetal MRI
Maternal and Paternal physical examination (for tuberous sclerosis)
Monitor for signs of hydrops
Do cardiac rhabdomyomas require surgery?
No, they usually regress after birth
Inheritance of Tuberous sclerosis?
Autosomal Dominant
Findings in patients with tuberous sclerosis
Skin: cafe au lait spots, shagreen patch, ungual fibromas
Brain: astrocytomas
Kidney: angiomyolipomas, renal cysts, renal cell carcinoma
Heart: Rhabdomyomas
Lungs: Lymphangio leiomyomatosis (LAM)
What is your differential diagnosis for a thoracic mass on ultrasound?
Bronchopulmonary sequestration (BPS)
Congenital pulmonary adenomatous malformation (CPAM)
Teratoma
CDH
Congenital high airway obstruction sequence
Bronchogenic cyst
Bronchial obstruction
Describe characteristic US features of a CPAM?
Lung mass with arterial supply from pulmonary artery
How do you distinguish between a CPAM and BPS?
BPS has a feeding vessel from the aorta
What are the different types of CPAM?
Macrocystic
Microcystic
How do you counsel a patient if a CPAM is identified on US?
Found a lung mass in the fetal chest
It has the potential to grow, so we will conitnue to monitor it
It can push the heart and cause hydrops
In most cases it will need resection after delivery due to risk of infection / malignancy
What is the natural history of CPAM diagnosed prenatally?
Greatest risk of growth is between 20-26 weeks
Usually regress in 3rd trimester, but they are still there (just harder to see on US)
What are potential complications related to CPAM?
Polyhydramnios
Preterm contractions / labor
Preterm delivery
Hydrops from cardiac failure (<10% of the time)
How do you follow a pregnancy if a CPAM is identified on US?
CPAM volume ratio (CVR) - CPAM Lxwxh X 0.52 / HC
CVR >1.6 = increased risk of hydrops / demise
What is the likelihood of associated anomalies with a CPAM?
10% risk of extra pulmonary anomalies (cardiac, renal, TE fistulas)
What is the likelihood of an underlying genetic condition if a CPAM is identified on US?
No known genetic cause
No recurrence risk
What additional workup do you recommend if a CPAM is identified on US?
Detailed US
Fetal echo
Serial evals of CPAM
Describe the US findings of CDH?
Stomach in chest
Heart displaced
On which side are CDHs more common?
Left sided (80-90%)
What workup do you perform if a CDH is identified?
Invasive testing Fetal echocardiogram MRI Serial ultrasounds Lung head ratio (LHR)
How is an LHR for CDH interpreted?
<1 high morbidity and mortality
1.0-1-4: increased risk of needing ECMO
>1.4 better prognosis
What % of CDH will have an associated genetic condition or karyotype abnormality?
10%
What genetic conditions are associated with CDH?
Trisomy 18 Trisomy 13 Fryns syndrome Pallister Killian Cornelia De Lange
What % of CDH will have another anomaly as well?
20%
How do you counsel a patient if a CDH is identified on US?
There is a defect in the part of the baby that separates the chest from the abdomen
It can cause problems with lung development because the fetal bowel comes into the chest and compresses the lung
We will follow the size of the lungs to help assess prognosis
If they are very compressed it may put the baby at a high risk of death or needing interventions to help survive after birth
Baby will need surgery to close the defect after birth
What are potential fetal complications that can develop as a result of CDH?
Polyhydramnios
Pulmonary hypoplasia
How do you follow a pregnancy complicated by CDH?
Serial ultrasounds looking at LHR, polyhydramnios
What factors on US are associated with a worse prognosis for CDH?
Liver up
LHR <1
Describe how you calculate the o/e LHR?
Trace area of contralateral lung / head circumference
Or L x W of contralateral lung / head circumgerence and compare to expected ratio for that gestational age
How do you interpret the LHR results?
severe: <25%
moderate: 26-45%
mild: >45%.
What is the prognosis for a fetus with CDH and an LHR of 15%?
Poor prognosis
What is the prognosis for a fetus with CDH and an LHR of 50%?
Good prognosis
Treatment options for CDH?
Delivery considerations?
Only investigational: FETO (Fetoscopic endoluminal tracheal obstruction)
Possible EXIT procedure for fetuses with poor prognosis based on LHR
What is a Dandy walker malformation?
Developmental anomaly of the cerbellar vermis
Describe classic ultrasound findings with a Dandy Walker malformation?
Cystic dilation of fourth ventricle
Complete/partial agenesis of the cerebellar vermis
Upward displacement of the tentorium
Ventriculomegaly
If a Dandy Walker malformation is identified, how will you counsel the patient?
> 50% risk of neurodevelopmental delay
If ventriculomegaly is severe, >50% mortality rate
Possible need for shunts and complications associated with shunts
What is the likelihood of an associated genetic or karyotypic abnormality with Dandy Walker malformation?
30%
If a Dandy Walker malformation is identified, what is your differential diagnosis?
Vermian dysgenesis
Blake’s pouch cyst
Mega Cisterna Magna
Arachnoid cyst
If a Dandy Walker malformation is identified, what workup do you recommend?
Detailed fetal anatomy fetal echocardiogram amniocentesis Neurosonography MRI fetal Growth Antenatal testing
In the setting of a Dandy Walker malformation and if an amniocentesis is performed, what testing will you send on the fluid?
FISH with karyotype reflex to CMA if normal
Describe the proper technique for measuring the lateral ventricle on a fetal ultrasound?
Head in axial plane
Head is majority of image
Midline falx
Atrium and occipital horn clearly imaged
Atrium of lateral entricle measured at level of parietooccipital groove
Calipers placed on the medial and lateral walls of atrium perpendicular to the long axis of the ventricle
How is ventriculomegaly defined for a fetus?
Lateral ventricles > 10mm
What is mild ventriculomegaly? prognosis?
10-12mm (>90% normal outcome)
What is moderate ventriculomegaly?
12.1-14.9mm (75-90% normal outcome)
What is severe ventriculomegaly? prognosis?
> =15mm (50% severe long term sequellae)
Increased risk for death
When ventriculomegaly is identified, what is your differential diagnosis?
Idiopathic / isolated
Aneuploidy
Structural (Acqueductal stenosis, etc)
Infection
What % of cases of ventriculomegaly are bilateral?
slightly less than 50%
If ventriculomegaly is identified on prenatal US, what workup do you recommend?
Detailed ultrasound Invasive genetic infectious studies (cmv/toxo) MRI Follow ventriculomegaly, if progressive or severe, consider neurosurgery consult
What is the likelhood of an underlying genetic or karyotypic abnormality in fetuses with isolated ventriculomegaly?
5% abnormal karyotype
15% abnormal microarray
If an amniocentesis is performed for a fetus with ventriculomegaly, what tests do you perform on amniotic fluid?
Karyotype
Microarray
CMV / Toxoplasma PCR (Or IgG / IgM if decline amnio)
What is the role of MRI in the evaluation of fetal ventriculomegaly?
To find malformations not seen on ultrasound
How do you follow a fetus with ventriculomegaly?
Serial ultrasounds for growth and evolution / resolution of ventriculomegaly (q4 weeks)
When do you recommend delivery for fetuses with ventriculomegaly?
Usual obstetric recommendations for timing
Do you consider ventriculomegaly an indication for c/s?
No, I base that decision on the standard obstetric indications
How do you define FGR?
EFW <10th percentile
OR
AC <10th percentile
Which US measurement is the most sensitive for FGR?
AC
How is a cerebellar measurement useful in FGR?
growth of the transverse cerebellar diameter is unaffected by intrauterine growth retardation
What is your differential diagnosis once FGR is identified in the second trimester?
Maternal HTN
Placental dysfunction
Genetic abnormalities
What is your differential diagnosis once FGR is identified in the third trimester?
placental insufficiency (milder)
How do you work up the patient with FGR diagnosed in the 2nd trimester?
Detailed U/s
Diagnostic testing (sonographic abnormalities, polyhydramnios, early onset)
CMV testing (PCR on amnio if getting amnio)
UA Doppler, Cardiotocography
How do you work up the patient with FGR diagnosed in the 3rd trimester?
Detailed U/s
Diagnostic testing (sonographic abnormalities, polyhydramnios, early onset)
CMV testing (PCR on amnio if getting amnio)
UA Doppler, Cardiotocography
When do you recommend a genetic workup in the setting of FGR?
Polyhydramnios
Anomaly
<32 weeks
If you are to perform a genetic workup for FGR, what workup will you perform?
Microarray / Karyotype
When do you recommend an infection workup in the setting of FGR?
If other findings are suggestive
What infection workup do you perform for FGR?
CMV PCR on amniocentesis
How do you manage FGR 3-9th percentile with normal Dopplers?
Weekly CTG
Weekly Doppler velocimetry of umbilical arteries x 1-2 weeks, then q 2 weeks if stable
Growth ultrasound every 2-3 weeks
Delivery at 38-39 weeks
How do you manage FGR <3rd percentile with normal Dopplers?
Weekly CTG
Weekly Doppler velocimety of umbilical arteries
Growth u/s q 2 weeks
Delivery at 37 weeks
How do you manage FGR with elevated Dopplers >95th%?
Weekly CTG
Weekly Doppler velocimety of umbilical arteries
Growth u/s q 2 weeks
Delivery at 37 weeks
How do you manage FGR with AEDV?
Consider inpatient management / steroids for FLM Doppler 2-3x weekly CTG 2x per week if outpatient EFW q2 weeks Delivery at 33-34 weeks
How do you manage FGR with REDV?
Inpatient admission /steroids
CTG 1-2x daily
EFW q 2 weeks
Delivery at 30-32 weeks
What is the role of Doppler studies in the management of FGR?
Helps assess for deterioration and guide timing of delivery
Shown to reduce risk of perinatal death, IOL and c/s.
What does an elevated SD ratio indicate?
Increased placental resistance
Describe how you perform an umbilical artery Doppler study?
A systolic/diastolic flow taken from the free-floating portion of the umbilical cord (ideally near cord insertion at abdomen)
With angle as close to 0 as possible
Without fetal breathing
What does absent or reversed diastolic flow in the umbilical artery indicate?
Suggestive of placental insufficiency
With increased UA index, 30% of villous vessels are abnormal vs 60-70% with AEDF or REDF, 60-70%AEDF suggests 50-80% intrauterine hypoxia
How do you manage a patient with absent diastolic flow in the umbilical artery at 26 weeks?
Consider inpatient management / steroids for FLM Doppler 2-3x weekly CTG 2x per week if outpatient EFW q2 weeks Delivery at 33-34 weeks
How do you manage a patient with absent diastolic flow in the umbilical artery at 36 weeks?
Steroids and Delivery (without waiting for second dose)
How do you manage a patient with reversed diastolic flow in the umbilical artery at 26 weeks?
Inpatient admission /steroids
CTG 1-2x daily
EFW q 2 weeks
Delivery at 30-32 weeks
How do you manage a patient with reversed diastolic flow in the umbilical artery at 36 weeks?
Steroids and Delivery (without waiting for second dose)
What does absent or reversed diastolic flow in the Ductus venosus indicate?
Has been associated with increased risk of stillbirth, but prospective studies are needed to help guide its use in clinical practice
Why does oligohydramnios develop in FGR?
Shunting of fetal blood away from the kidneys to more vital organs. Decreased renal perfusion leading to reduced urine production which leads to oligohydramnios
When do you recommend delivery for FGR?
3-9 percent: 38-39 <3rd percent: 37 Elevated Doppler: 37 AEDV: 33-34 REDV: 30-32
How is FGR diagnosed in multiple gestations?
Same as singleton or discordance more than 25%
What is your differential diagnosis when FGR is diagnosed in a single fetus of a di/di twin gestation?
Placental insufficiency
Infection
Structural anomalies
What workup do you perform when FGR is diagnosed in a single fetus of a twin gestation?
Detailed U/s
Diagnostic testing (sonographic abnormalities, polyhydramnios, early onset)
CMV testing (PCR on amnio if getting amnio)
UA Doppler, Cardiotocography
How do you counsel the patient about the risks of FGR in a single twin?
oligohydramnios nonreassuring fetal heart testing (NRFHR) preterm birth and its consequences preeclampsia and fetal death
How do you follow a twin gestation when FGR has been diagnosed in one or both twins?
Weekly Doppler velocimetry
NST twice weekly
Growth u/s q 2 weeks
What is the significance of discordant twin growth?
Discordance with AGA growths are not at increased risk of fetal or neonatal morbidity and mortality
Discordance with sFGR growth associated with an increased risk of major neonatal morbidity
How is CMV infection transmitted?
Blood, urine, saliva
Do you recommend screening for CMV routinely in pregnancy? Why or why not?
No, poor predictive value
Increased harm due to false positives
How is a primary CMV infection diagnosed?
Seroconversion, IgM/IgG+ with low avidity
How is a recurrent CMV infection diagnosed?
IgM/IgG+ with high avidity
How do you counsel a patient with a positive CMV IgM and negative IgG results?
Could be a false positive (autoimmune disease, other virus)
Wait 2 weeks and recheck (If IgG now positive then acute infection)
How do you counsel a patient with a positive CMV IgM and a positive CMV IgG result?
Unclear if this is a new infection, test avidity
What does high IgG avidity for CMV mean?
Infection >6 months ago
What does low IgG avidity for CMV mean?
Recent infection (within 2-4 months)
What are maternal risks of CMV infection?
Minimal, usually asymptomatic
What are maternal symptoms of CMV infection?
Mostly asymptomatic
But can have mild viral like symptoms (Myalgia, malaise, fever)
How likely are women with CMV to be symptomatic?
unlikely
What ultrasound findings are consistent with in utero CMV infection?
Microcephaly Periventricular calcifications Ventriculomegaly Echogenic bowel FGR Hydrops (ascites, pericardial effusion)
How is in utero CMV infection confirmed?
Amniocentesis, CMV+ PCR
When should you do an Amniocentesis for CMV?
> 21 weeks gestation
>6 weeks from maternal infection
What is the risk of fetal transmission of CMV by trimester?
Greatest risk of having a fetal infection is in 3rd trimester
But the later you get it the lower the risks to the fetus
Which patients are candidates for CMV serology?
US findings
Known exposure
What are the fetal risks of sequellae in in utero CMV primary vs recurrent infections?
Sequellae: 30-50% in primary infection
8% develop sequellae in recurrent infection
What are some of the neonatal findings of CMV in utero?
rash jaundice hepatosplenomegaly Low IQ hearing loss vision loss cognitive/motor dysfunction
What is the most common neonatal morbidity associated with reactivation of maternal CMV infection and subsequent in utero fetal CMV infection?
Sensorineural hearing loss
What percentage of cmv infected moms will have a fetal infection?
What percent of these will be symptomatic
30-40% fetal infection
90% asymptomatic at birth
How do you counsel a patient regarding neonatal outcomes if the neonate is born SYMPTOMATIC following a primary maternal infection with CMV?
50% are permanent sequellae
How do you counsel a patient regarding neonatal outcomes if the neonate is born and ASYMPTOMATIC following a primary infection with CMV?
25% develop sequella by age 2 - most commonly hearing loss)
How do you counsel a patient regarding neonatal outcomes if the neonate is born and ASYMPTOMATIC following a recurrent infection with CMV?
8% will develop sequellae by age 2
How is maternal infection with syphilis diagnosed?
Non-treponemal tests (RPR, VDRL)
Confirm with a treponemal tests FTA-ABS
How do you counsel a patient with a positive RPR or VDRL?
False positives may occur
Confirm with antitreponemal ab tests - FTA-ABS
What are the explanations for a false positive RPR or VDRL?
Autoimmune diseae
Tumor
Advanced age
Acute illness
Syphilis stages?
Primary: Chancre
Secondary: Rash, fever, malaise, systemic pathology
Tertiary: Gummatous, cardiovascular, neurosyphillis
Latent: Asymptomatic
Which stages of syphillis is vertical transmission increased?
Primary
Secondary
and Early latent (<1 year)
40-50% fetal transmission
Risk factors for syphilis transmission?
Early stage Infection lat end of pregnancy Lack of treatment <30 days between treatment and delivery Delivery <36 weeks High nontreponemal titer at treatment and delivery
US Findings in congenital syphilis?
Hepatomegaly Placentomegaly Anemia Polyhydramnios Ascites / Hydrops But normal US does not exclude infection
Risk of stillbirth in congenital syphilis?
1/3
How is syphilis treated in pregnancy?
Primary, Secondary or Early latent: PCN G 2.4 million U IM x 1
Late latent: PCN G 2.4 Million Units IM x 3 (If dose missed, restart treatment)
Neurosyphilis: PCNG 2.4 million units IV q4 x 10-14 days
How do you treat syphilis in patients with PCN allergy?
PCN skin testing, if IgE mediated reaction confirmed -> desensitization by an allergy specialist
What are the risks of penicillin desensitization?
Anaphylaxis, why its usually done as an inpatient in a critical care setting
How to assess treatment success in syphilis?
RPR or VDRL drawn at baseline
Repeat at 6 and 12 months
4 fold increase = failure
4 fold decrease = success
What is sometimes a side effect of syphilis treatment?
Jarisch Herxheimer reaction 1/3 of patients Fever HA Myalgias Sweating Hypotension
How do you manage Jarisch-Herxheimer reaction?
Tx: Supportive care (nsaids, fluids), manage in house due to worry about labor initiating from inflammation
How is in utero syphilis infection confirmed?
Amniocentesis is not recommended due to associated complications and that results do not change management
How is maternal infection with parvovirus diagnosed?
Serology, IgM+, IgG-
What is the risk of fetal infection if mom is infected?
25-30%
What is the risk of nonimmune hydrops fetalis (NIHF) if maternal infection is confirmed?
3-4%
How long after parvovirus infection in mom does hydrops develop for baby?
50% in 2-5 weeks
93% in 8 weeks
Why does parvovirus cause NIHF?
Cytotoxic effect on RBC precursors
Do you recommend screening for parvovirus routinely in pregnancy? Why or why not?
No, because risk of hydrops is low in patients screened 1/5000
How do you counsel a patient with a positive parvovirus IgM and negative IgG results?
Management?
Could be a new infection or a false positive
Repeat testing in 2-4 weeks
Start screening as if positive until results return
How do you counsel a patient with a positive parvovirus IgM and positive IgG results?
This is suggestive of infection between 1wk to 6 months
How do you counsel a mother with confirmed parvovirus infection?
She has a 25% risk of passing it on to her fetus
And if she passes it on, theres a 2-6% of fetal hydrops fetalis due to anemia
If that happens a fetal blood transfusion would be needed to help decrease the risk of mortality/morbidity in the fetus
We can monitor the pregnancy for the next 12 weeks to assess the likelihood of fetal infection by doing serial ultrasounds evaluating for Hydrops fetalis and MCA Doppler velocimetry.
How is parvovirus transmitted?
Body fluids, usually from little kids
What are maternal risks of parvovirus infection?
Minimal risks
What are maternal symptoms of parvovirus infection?
Mild viral like illness
What percentage of patients infected with parvovirus are symptomatic?
50%+
What US findings suggest possible in utero parvovirus infection?
Hydrops
abdominal calcifications
cardiomegaly
placentomegaly
How is in utero parvovirus infection confirmed?
Amniocentesis with Parvovirus PCR
In which trimester of pregnancy is the greatest risk of fetal infection?
Increased risk of fetal loss in first half of pregnancy
Which patients are candidates for parvovirus serology?
Exposure
+Ultrasound findings
How do you follow a patient if in utero parvovirus infection is suspected or confirmed?
MCA Dopplers and Hydrops evaluation q 1-2 weeks for 10-12 weeks
Describe how you perform an MCA Doppler study?
Angle of insonation as close to zero degrees as much as possible (30 degrees or less), 2mm above branching of the MCA from the circle of willis
How do you interpret MCA Doppler study findings?
> 1.5 MoM suggestive of fetal anemia
How do you counsel a patient if she has an MCA PSV > 1.5 MoM?
Suggestive of fetal anemia
Intrauterine transfusion until 34 weeks with anticipated delivery between 37-38 weeks gestation
Describe your management of a patient with confirmed or suspected in utero parvovirus infection with an MCA PSV > 1.5 MoM at 20 weeks gestation?
Offer termination
Weekly MCA PSV and hydrops checks x 12 weeks
If >1.5MoM, repeat in 1 day, if still positive, Offer transfusion
Describe your management of a patient with confirmed or suspected in utero parvovirus infection with an MCA PSV > 1.5 MoM at 30 weeks gestation?
Weekly MCA PSV and hydrops checks x 12 weeks
If >1.5MoM, repeat in 1 day, if still positive, Offer transfusion
Describe your management of a patient with confirmed or suspected in utero parvovirus infection with an MCA PSV > 1.5 MoM at 36 weeks gestation?
Delivery
How do you counsel a patient regarding long term neonatal outcomes in the setting of fetal parvovirus infection?
There is a risk of neurodevelopmental delay, but long term neurodevelopment risks are unclear
Are patients at risk of parvovirus infection by transmission from puppies who have received parvovirus vaccination? Why or why not?
No, the human parvovirus B19 is different from the puppy parvovirus
How is maternal infection with toxoplasmosis diagnosed?
Toxoplasma IgG / IgM
Usually sent to palo alto (reference laboratory)
Do you routinely recommend screening for toxoplasmosis in pregnancy? Why or why not?
No, very poor predictive value, only order if clinical suspicion
How do you counsel a patient with a positive toxoplasmosis IgM and negative IgG result?
This could be a true infection and that we will send to a reference lab
How do you counsel a patient with a positive toxoplasmosis IgM and positive IgG result?
This could be a true recent infection and that we will send to a reference lab to confirm and perform avidity testing to assess if this is a recent infection
How is toxoplasmosis infection transmitted?
Garden (unwashed soil)
Changes cat litter
Unwashed vegetables
What are maternal risks of toxoplasmosis infection?
Rarely symptomatic
Can have flulike illness
What ultrasound findings are consistent with in utero toxoplasmosis infection?
Intracranial calcifications Intrahepatic calcifications Ventricuolmegaly Echogenic bowel Microcephaly
How is in utero toxoplasmosis infection confirmed?
Amniocentesis for toxoplasma pcr
In which trimester of pregnancy is the greatest risk of fetal infection with toxoplasmosis?
Increases with increasing gestational age, but less likely to have a symptomatic neonate as the pregnancy continues
Which patients are candidates for toxoplasmosis serology?
US Findings +/- history of:
Garden (unwashed soil)
Changes cat litter
Unwashed vegetables
How do you counsel a patient regarding fetal and neonatal outcomes following in utero toxoplasmosis infection?
Complications occur in 1/3 of infected fetuses and include:
Neonatal chorioretinitis
Neurodevelopmental delay
PTB, FGR
How do you treat a patient with in utero toxoplasmosis?
<18 weeks: Spiramycin
>18 weeks: Pyrimethamine-sulfadiazine + Folinic acid (decreases bone marrow toxicity from pyrimethamine)