RESULTS
During the study period, 196 women with PPROM between 28+0 to 33+6 weeks
gestation were considered for study. Out of these, 66 had associated
obstetric or medical conditions (preeclampsia, diabetes mellitus,
intrahepatic cholestasis of pregnancy etc) and were thus excluded.
Another 42 women went in spontaneous labor within 48 hours of admission
and hence were not considered for study. Eight women declined to
participate in the study and 10 women could not be evaluated within 48
hours of admission as shown in figure 1.
Out of 70 recruited patients with PPROM, 44 neonates were diagnosed with
FIRS based on either raised IL-6 levels in cord blood or by presence of
placental histologic features. Of these 44 neonates, all had raised IL-6
levels but only 16 patients had placental histologic features of FIRS.
The overall prevalence of FIRS in cases of PPROM in our study was
62.86%. The mean IL-6 levels in the FIRS group was 77.37±74.51pg/ml
whereas in the Non FIRS group it was 5.75±2.80pg/ml. Based on the
presence of fetal inflammatory response syndrome, the study subjects
were divided into the FIRS group and the Non FIRS group.
Both the groups were comparable with respect to maternal demographic
parameters including age, education, parity, socioeconomic status.
Maternal and neonatal descriptive characteristics for study participants
are depicted in Table 1 which were found to be comparable between FIRS
and Non FIRS group. The mean gestational age at the time of birth in the
FIRS group was 32.78±1.23 weeks with a latency period of 8.77±7.94 days.
These findings were comparable to the Non FIRS group where mean
gestational age was 33.56±0.89 weeks and a latency period of 7.12±6.19
days. 75% of women in the FIRS group went in spontaneous labor and
almost 80% women delivered vaginally. The mean birth weight was
1.59±0.269 kg in the FIRS group.
The Fetal urine production rate (FUPR) at time of delivery was
significantly reduced in neonates who had evidence of FIRS at birth as
compared to neonates without evidence of FIRS (13.89±8.06 ml/h vs
25.89±4.94ml/h). This association of FUPR with FIRS was found to be
statistically highly significant with a p-value of <0.0001.
Out of 41 patients with reduced FUPR prior to delivery, 39 babies were
subsequently found to have FIRS while out of 29 patients with normal
FUPR antenatally, only 5 babies had features suggestive FIRS (Table S1).
The mean IL-6 levels in patients with reduced FUPR was 67.21 ±
69.86pg/ml which was significantly higher as compared to 27.53 ± 60pg/ml
in patients with normal FUPR. Neonates with reduced FUPR antenatally had
significantly higher rates of severe neonatal morbidity, early neonatal
sepsis, prolonged NICU stay and hospital stay shown in table 2
(58.54%,9.05 ± 7.52days, 12.83±8.50days). The neonatal mortality was
4.88% in neonates with reduced FUPR. The occurrence of RDS, NEC was
significantly high in neonates with recued FUPR as compared to normal
FUPR.
Out of 44 neonates in the FIRS group, 27 neonates (61.36%) had severe
neonatal morbidity as compared to 8 neonates (30.77%) affected in the
Non FIRS group. 27 babies had evidence of early onset neonatal sepsis in
the FIRS group as compared to only 4 neonates in the Non FIRS group.
Among the FIRS group, 15 (34.09%) neonates had RDS, 3 (6.82%) had NEC
in comparison to the Non FIRS group where 4 (15.38%) had RDS and
1(3.85%) had NEC. Overall neonatal mortality was 4.55% belonging to
FIRS group only (Table S2).
In our study, out of 70 patients with PPROM 42 had evidence of
chorioamnionitis (clinical, bacteriological, histologic
chorioamnionitis) making a prevalence of 60%. Of these 42 mothers
having evidence of chorioamnionitis, 38 neonates had evidence FIRS while
in the absence of chorioamnionitis, only 6 out of 28 neonates had
evidence of FIRS. All the 16 patients with histologic feature of FIRS
had features of chorioamnionitis also on placental histopathology while
none of the patients showed features of FIRS in the absence of
histopathological chorioamnionitis (Figure S1, Figure S2).
Table 3 shows correlation IL-6 levels and placental histopathological
features of FIRS with neonatal outcomes, it was found that out of 16
patients who had raised IL-6 levels as well as histopathological
features of FIRS, 15 (93.75%) neonates developed sepsis, 9 (56.25%)
had RDS, 2 (12.5%) had NEC. In 28 cases with only raised IL-6 levels
but no histologic evidence of FIRS, 12 (42.86%) neonates had sepsis, 6
(21.43%) developed RDS while 1 (3.57%) had NEC. In 26 patients with
PPROM and no biochemical and histologic evidence of FIRS, only 7
(26.92%) neonates developed sepsis, 4 (15.38%) developed RDS.