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INTRODUCTION: -
The issue of obstetric consequences of APA syndrome is now
well settled in the obstetric academics. It is pertinent now to
take it from the realms of academic world to day to day
practice. It is only a little over one and a half-decade that
this syndrome has come into sharp focus in obstetrics. Its
bearings were known well to physicians and soon obstetricians
picked up the trail.
ADVERSE OUTCOMES: -
APA syndrome is an autoimmune condition that has profound
bearing on obstetric conditions at times seemingly diverse.
Recurrent spontaneous missed abortions, IUGR, recurrent still
births, accidental hemorrhage and thromboembolism are some
diverse conditions which have this as its etiological factor.
WHAT ARE ANTIPHOSPHOLIPID ANTIBODIES: -
Antiphospholipid Antibodies or APA were identified to be of
six types. Of these six, three were important for us clinicians:
-
Anticardiolipin antibodies ( ACA)
-
Lupus anti coagulant ( LAC)
-
Biologically False Positive Serological Test For Syphilis (BFPSTS).
These three are inter-related and presence of one may indicate
the presence of other as well. However, the international
recommendation today suggests that if one is interested in using
LAC as a test for Antiphospholipids than it must fulfill the
following criteria:
1) Prolongation of APTT
2) That the abnormality is caused by inhibition
3) That this inhibitor is directed against phospholipids.
In the same way for BFPSTS to be exclusively used for testing
Antiphospholipids, the following are the criteria:
Person should serologically test continuously positive for
syphilis for 6 months without treponemal infection.
No such recommendations are made for ACA and thus this is the
test primarily involved in picking up APA cases. However, what
clinical significant has the testing of IgM and IgG have in ACA,
bearing their cross reactivity in mind, is a matter currently
under investigations.
PATHOPHYSIOLOGY INVOLVED: -
APA are antibodies with a strong activity against vascular
tree. APA are a diverse family of auto antibodies which share a
common reactivity with negatively charged phospholipids. The
most common theories for their mechanism of action may be
divided into:
1) Those that ascribe APA to disrupt platelet function and
2) Those that postulate that APA interfere with the function of
endothelial cells.
A major advance was made by the demonstration that both LA and
ACA require plasma protein cofactors to exert their action. They
are charged particles. By this virtue they have a tendency to
interact with the decidual-placental interface. They tend to
bring about changes in vascular endothelium in such a way that
it reduces the caliber of the vessels. The vascularity is
affected and the effective number of vessels decline. This is
known as a state of decidual vasculopathy. Immunological
staining methods have shown a clear deposition of immune
complexes at the vessels of the deciduo-placental interface so
affected. These vascular changes in turn produce the resultant
manifestations of pre- eclampsia.
Once the vasospasm and vasculopathy occurs, the BP rises to
compensate for the poor vascularity. It is a natural mechanism
to maintain the placental blood flow. This produces
hypertension. Individual organs being so affected cause the
manifestations specific to these organs. This includes renal
prorteinurea, intracranial hemorrhage, IUGR, recurrent
stillbirths, accidental hemorrhage.
These
are all explainable by the vasculopathy of APA. No wonder these
cases also consistently test positive for APA.
DIAGNOSIS: -
Lab diagnosis of APA is currently done by ELIZA technique.
Usually the laboratory asks for an empty stomach of about 4
hours. Blood so collected is tested for Antiphospholipid
antibodies. A strong index of suspicion and a good laboratory
back up can make the diagnosis of APA syndrome in a given case,
easy. Diagnosis is also helped by asking a history of allied
complications of APA like RSA of missed type, Recurrent still
births, Recurrent IUGR, etc. The standard classification used
is:
Negative ® < 10 GPL units
Low positive ® 10-20 GPL units
Mod. Positive ® 20-100 GPL units
Strong positive ® > 100 GPL units.
Once the diagnosis is well established treatment plans are
instituted.
TREATMENT: -
Nearly 18 different protocols have been tried over the period of
years for the treatment of APA syndrome. But the main stay is
Heparin, Low dose Aspirin and corticosteroids. We use the
following protocol: -
· In interval period :
® For low and moderate positive, Aspirin in a dose of 1.2
mg/kg./day for three months – Allow a conception – Restart
aspirin in the same dose upto 36 weeks.
® For High positive, Prednisolone in a dose of 10 mgms./day for
3 months in the interval period. Allow conception- start aspirin
from 12 weeks upto 36 weeks.
· In Pregnancy:
® For these cases we give only the post-conception protocol of
aspirin specified above.
We have satisfactory results that are written in the section to
follow.
RESULTS: -
In our study 154 subjects testing positive for APA were given
the above treatment protocols. In the group where treatment
could be given pre conception as well as post conception, full
term delivery rates achieved were 88.3%. In the group where only
post conception treatment could be given, the same rate was
72.3%.The incidence of P.E. remote from term declined from 26.7%
to 3.3 %.
CONCLUSION: -
APA syndrome is difficult to understand but
easy to treat. This is in contrast to other conditions of RSA
that are easy to understand but difficult to treat Results of
treatment of APA syndrome are very satisfactory and gratifying.
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