HYDROPS FETALIS INFECTIOUS CAUSES
Category: Child Health
Abstract : hydrops fetalis infectious causes • The immature fetus is particularly
susceptible to overwhelming viral and bacterial infection. Those agents, which
do not kill quickly, may cause smoldering generalized infections with
myocarditis, suppressed erythropoiesis and myelopoiesis, hemolysis, and
hepatitis. Such infections may lead to hydrops fetalis. Those agents reported to
be causa
hydrops fetalis infectious causes
• The immature fetus is particularly
susceptible to overwhelming viral and bacterial infection. Those agents, which
do not kill quickly, may cause smoldering generalized infections with
myocarditis, suppressed erythropoiesis and myelopoiesis, hemolysis, and
hepatitis. Such infections may lead to hydrops fetalis. Those agents reported to
be causative, to date.
This list will change with time as other agents, yet to
be unidentified, are demonstrated to cause hydrops.
• The association of
congenital syphilis with hydrops is classic. Fetal and placental edema
accompanied by serous effusions first was described generations ago. However,
the surprising frequency with which maternal serologic tests for syphilis may
appear negative in this condition is less well known.
o The prozone
phenomenon, observed during primary and secondary maternal syphilis, occurs when
a higher-than-optimal amount of antisyphilis antibody in the tested maternal
sera prevents the flocculation reaction typifying a positive result in reagin
tests. In these circumstances, dilution of the tested serum is necessary to make
the correct diagnosis. Thus, serum dilution (to as much as 1:1024 or greater)
should be routine in high-risk situations and should certainly be used in any
individual in whom fetal hydrops of unknown etiology exists.
o Early,
accurate diagnosis of this infection is critical, since fetal treatment is
available and effective. Several viral infections have been associated with
fetal hydrops.
• The number of viruses implicated and the frequency of
these cases have paralleled the increased recognition of this association and
the improved simplicity and sensitivity of diagnostic methods. Hydrops in these
conditions appears to be the cumulative result of viral effects on marrow,
myocardium, and vascular endothelium. Currently, reports of effective fetal
treatment are rare.
• Of particular interest is recent evidence of how
commonly acute B19V infection is a cause of fetal hydrops. The virus was first
identified in 1974 and first linked with fetal hydrops 10 years later. Evidence
published since then suggests this virus may be the single most important
currently recognized cause of fetal hydrops.
o Parvovirus may be the cause of
as much as one third of all incidents of hydrops fetalis. The virus directly
attacks red cell precursors and is visible as intranuclear inclusions in stained
RBC preparations. Thrombocytopenia is usually present, also.
o Outcome in
such fetuses is surprisingly good; spontaneous resolution occurs in
approximately one third of such incidents, and approximately 85% of those who
receive fetal transfusions survive. The virus is not teratogenic and, despite
reports of viral persistence in myocardial and brain tissues, neurodevelopmental
outcome in survivors appears to be normal. Early, accurate diagnosis, using
maternal serologic and/or molecular biologic PCR techniques, is essential.
Positive results are usually confirmed by direct fetal PCR, hemoglobin,
hematocrit, and platelet studies to plot a proper treatment plan.
• An
interesting association of hydrops exists with fetal meconium peritonitis. At
least 16 such cases are found in the literature. No baby reported before 1991
had evidence of infection; however, CMV (1), hepatitis B (1), and B19V (5) were
found in 7 of 8 cases reported since 1991. The only instance of meconium
peritonitis and hydrops without confirmed infection in these later reports was
probably iatrogenic, since it followed paracentesis with subsequent placement of
a peritoneoamniotic shunt. These observations suggest that the coexistence of
hydrops and meconium peritonitis should be assumed to be related to fetal
infection until proven otherwise.
Hit: 274 times
Related Articles in Child Health :
|
Advertise with Health Information Encyclopedia