Book of Medical Disorders in Pregnancy - Tintash

Fig6.3: Shows location of kidney in the
body.
(b) Asymptomatic bacteriuria - The
incidence of asymptomatic bacteriuria is
about 5% in the pregnant population.
There are no symptoms. Diagnosis will
be established when the colony count of
bacteria in the urine exceeds 100,000 or
more per mi. of urine. In cases where
particular care is taken in establishing a
clean midstream catch, a colony count of
10,000 per mi. may be significant. Cass
was one of the workers who first drew
attention to the importance of identifying
patients with asymptomatic bacteriuria.
His work appeared to demonstrate an
increase in prematurity and perinatal loss
in patients who suffered from this problem.
In our unit, we have been unable
to arrive at the conclusions stated by
Casso However, all would agree that
early prenatal examination of the urine
for the presence of bacteria is important,
because of the women who develop
acute pyelonephritis in pregnancy, 75%
of them come from the group of patients
demonstrating asymptomatic bacteria.
Screening for bacteria in the urine in
early pregnancy is expensive. Our unit
has not been satisfied with the chemical
tests for bacteria. Undoubtedly, the most
effective and least expensive screening
test is microscopic examination of a
Gram stain of the urine. The presence of
bacteria in a high power field of UN
91
spun urine indicates a colony count in
excess of 100,000. The urine under these
circumstances should then be sent for
culture and sensitivity.
(c) Acute pyelonephritis - Acute
pyelonephritis in pregnancy is the most
common cause for medical admission to
hospital during pregnancy. The
incidence throughout the world varies
from 1 % to 5%. In our own unit it is
approximately 2%. The signs and symptoms
are those of acute onset of fever,
pain over the flanks occasionally
radiating down along the course of the
ureter and into the bladder. Occasionally
the pain is associated with frequency and
dysuria. The presence of rigor, high
fever associated with renal tenderness,
nearly always indicates an involvement
of the renal parenchyma.
Examination of the urine usually makes
the diagnosis easy because of the
presence of massive pyuria. In rare
instances, however, ureteric obstruction
may obscure the flow of infected urine
and the urinary sediment may be
relatively free of pus. Although the
classic case of pyelone-phritis in
pregnancy is easy to diagnose, the
presence of nausea, vomiting and right
lower quadrant pain may raise the
suspicion of acute appendicitis. This is
an extremely important differential point
to be established. In cases of high fever,
marked ureteric tenderness and colicky
pain, it may be necessary to carry out an
IVP to exclude ureteric obstruction from
renal calculi. The commonest organism
to cause acute pyelonephritis is E. coli,
but a spectrum of organisms may be the
offending bacteria, therefore, culture and
sensitivity of the urine should be obtained
prior to the institution of treatment.