Association of Chlamydophila pneumoniae infection and hypertension during pregnancy - A case control study

The association of Chlamydophila pneumoniae infection with essential hypertension is known but its association with hypertension during pregnancy is controversial. Hence, this study aimed to explore the association of C. pneumoniae infection with hypertension during pregnancy. The objectives were to compare the presence of C. pneumoniae DNA in trophoblastic cells of placenta between hypertensive and normotensive pregnant women and to find out the presence of inflammatory marker (HSP-60) and the seropositivity (IgG and IgA) of C. pneumoniae in them.

The study was conducted at a tertiary-care institute, in South-India between 2018 and 2020. Women with hypertension during pregnancy were study group (75) and normotensive pregnant women were control group (75). IgG and IgA antibodies, HSP-60 against C. pneumoniae were estimated by ELISA from 5 ml of venous blood. C. pneumoniae DNA was extracted from placental tissue after delivery and tested by RT-PCR.

The association between C. pneumoniae DNA, seropositivity and hypertension was determined by student test and univariate regression analysis.

C. pneumoniae DNA was detected in the placenta of 29.3% with hypertension and none in controls and the odds was 6.5 (OR-6.5, CI 95%). HSP-60 was elevated in women with preeclampsia and not in gestational hypertension and controls. IgA was not detected and IgG was positive in 15.2% of women with preeclampsia.

There is a significant association between C. pneumoniae infection and hypertension during pregnancy and further studies are required to fulfil the Koch's postulates to prove or disprove it as a causative agent.