Rubella in Pregnancy - Max Brinsmead MB BS PhD

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Transcript Rubella in Pregnancy - Max Brinsmead MB BS PhD

Malaria in Pregnancy
Max Brinsmead MB BS PhD
May 2015
Malaria in PNG
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Endemic & stable in coastal areas
Highlands subject to epidemics with high mortality
More than 1.6M cases in 2008 with 23,500
admission and 638 deaths
About 15% of cases attending health centres or
hospital are confirmed
70 – 80% are due to P falciparum…
The remainder are P vivax
P falciparum has a high rate of Chloroquine
resistance
Global Fund will spend $US147M 2009 - 2014
Plasmodium in Pregnancy
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Adults in endemic areas have partial immunity
And this is transmitted to the fetus
Thus providing neonatal protection for about 6m
The placenta acts as a barrier to fetal parasitaemia
And HBF-containing RBCs are relatively resistant to
Plasmodium
But malaria still causes a high burden of illness
during pregnancy…
And this is best studied in the two susceptible
groups:
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The partially immune pregnant woman
The non immune pregnant woman
The Partially Immune Gravida
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Immunosupression of pregnancy results renders
malarial attacks more common and severe
Especially in the young and primigravida
Older multigravida develop anti-adhesive antibodies
that provide more specific protection
Parasite density typically increases in pregnancy
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Up to 12x higher than in non pregnant individuals
Reaches a peak in mid pregnancy with splenic
enlargement
Then, as the placenta takes on the phagocytic role,
the spleen shrinks and parasite density falls towards
term
But rebounds again in the puerperium
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But don’t miss a bacterial cause for puerpereal fever
The Partially Immune Gravida(2)
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Malarial attacks are often asymptomatic
But haemolytic anaemia typically beginning at 16-24
weeks and gets progressively worse
Is compounded by folate deficiency as erythropoiesis
increases
In the placenta the parasites cause intervillous
inflammatory change, trophoblastic and BM damage that
is partly immune mediated.
The results of this placental damage include…
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IUGR secondary to O2 and nutrient deprivation
Risk of IUFD
Premature labour perhaps due to the release of toxic cytokines
Will be aggravated by other causes of maternal anaemia
and HIV
Non Immune Gravida
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Are at risk of clinically severe malarial attacks
Including cerebral malaria
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That has up to 50% mortality
Complications include
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Severe anaemia
Hypoglycaemia
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Acute pulmonary oedema
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Sometimes from Quinine Rx
Especially immediately after delivery
More prone to pneumonia and UTI
The high fever can cause
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Premature labour
IUFD
Fetal distress in labour
Congenital Malaria
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Notwithstanding the usual placental block to
Plasmodium…
Up to 15% of babies born to infected mothers have
parasitaemia…
Presumably due to breaches in the maternal-fetus
interface during labour…
But they are protected for up to 6m from clinical
disease…
By antibodies transferred from the mother.
However, babies born to non immune mothers may
be in trouble
Treatment of Malaria in Pregnancy
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Complicated by resistance of P. falciparum to
Chloroquine
So follow current local guidelines
Semi immune women can be treated as outpatients
Indications for hospitalisation
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Non immune women
Intolerant of outpatient therapy
Not responding to outpatient therapy
Complicated malaria
Fluid replacement and fever control is important
Vivax usually responds to Chloroquine
Complicated Malaria in Pregnancy
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Is a medical emergency
Lumbar puncture to exclude bacterial meningitis
The prognosis is poor when…
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>5% of RBCs are parasitised
There is severe leucocytosis
CSF glucose is low
HB is <7.0 or Haemotocrit <0.20
Blood urea is is >11.0
Assume Chloroquine resistance and treat
parenterally with drugs according to local guidelines
Begin with a loading dose according to bodyweight
and follow with maintenance therapy
Complicated Malaria in Pregnancy (2)
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General measures
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Nurse on the side
Ensure a clear airway
Reduce body temperature
Careful fluid balance with IV and IDC
Monitor blood glucose and renal function tests
Treating Complications
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IV Diazepam for convulsions
Transfusion for severe anaemia
Frusemide for pulmonary oedema
IV glucose for hypoglycaemia
Fluid restriction, K-absorbing resins, IV glucose and insulin or
dialysis for renal failure
Preventing Malaria in Pregnancy
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General measures to reduce mosquito bites
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Especially the use of insecticide-treated nets (ITN) and
indoor residual spraying (IRS)
Routine chemoprophylaxis with antimalarials, iron
and folate of partially immune gravida has been
shown to reduce the risk of…
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Maternal anaemia
IUGR and IUFD
Premature labour
Especially in young primigravid women
But at the risk of increasing the incidence of drug
resistance
It is desirable to begin as early as possible and
certainly before 20w when parasitaemia peaks
Preventing Malaria in Pregnancy (2)
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Non immune mothers…
Because some antimalarials are teratogenic
and…
Malaria is such a serious illness…
Non immune gravidas should avoid travel to
malarial areas if possible
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Follow current chemoproprophylaxis guidelines
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Especially areas with Chloroquine-resistant P. falciparum
Consult www
And take general measures to avoid mosquito
bites
Current WHO Guidelines for
Chemoprophylaxis
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Two doses of Pyrimethamine-Sulfadoxine (Fansidar)
After quickening
Not more frequently than monthly
However…
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This fails to eliminate parasites from peripheral or
placental blood (or both) in ≈ 80% women in endemic
areas
Resistance is then a real issue
And partial treatment may be more harmful than no
treatment at all
But other regimens are associated with
poor rates of compliance
Hyperactive Malarial Spleen Syndrome
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A condition that predates pregnancy
With massive splenic enlargement
Severe haemolytic anaemia complicated by bone
marrow suppression of erythropoesis
So there is leucopenia and thrombocytopenia
Associated with immunological abnormalities and
overproduction of IgM
In pregnancy the prognosis is serious
Admit to hospital and treat with regionally-specific
antimalarial drugs
Plus folate 5 mg/day
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