Fetal Loss and Preterm Birth Caused by Intraamniotic Haemophilus influenzae Infection, New Zealand

H. influenzae is as a rare but major cause of pregnancy-associated invasive disease.

Invasive Haemophilus influenzae infection during pregnancy can cause preterm birth and fetal loss, but the mechanism is unclear. We investigated 54 cases of pregnancy-associated invasive H. influenzae disease in 52 unique pregnancies in the Auckland region of New Zealand during October 1, 2008‒September 30, 2018. Intraamniotic infection was identified in 36 (66.7%) of 54 cases. Outcome data were available for 48 pregnancies. Adverse pregnancy outcomes, defined as fetal loss, preterm birth, or the birth of an infant requiring intensive/special care unit admission, occurred in 45 (93.8%) of 48 (pregnancies. Fetal loss occurred in 17 (35.4%) of 48 pregnancies, before 24 weeks’ gestation in 13 cases, and at >24 weeks’ gestation in 4 cases. The overall incidence of pregnancy-associated invasive H. influenzae disease was 19.9 cases/100,000 births, which exceeded the reported incidence of pregnancy-associated listeriosis in New Zealand. We also observed higher rates in younger women and women of Māori ethnicity.

RNAi-mediated gene function analysis in skin

We have recently developed a method for RNAi-mediated gene function analysis in skin (Beronja et al., Nat Med 16:821-827, 2010). It employs ultrasound-guided in utero microinjections of lentivirus into the amniotic cavity of embryonic day 9 mice, which result in rapid, efficient, and stable transduction into mouse skin. Our technique greatly extends the available molecular and genetic toolbox for comprehensive functional examination of outstanding problems in epidermal biology. In its simplest form, as a single-gene function analysis via shRNA-mediated gene knockdown, our technique requires no animal mating and may need as little as only a few days between manipulation and phenotypic analysis.

Fetal pulmonary injury following single high-dose intra-amniotic betamethasone treatment in preterm goat kids

OBJECTIVE

Fetal lung maturation is an extremely important process that is necessary for the survival of the neonates. Conventionally, corticosteroids are administered maternally for inducing fetal lung maturation in preterm fetuses. Alternatively, single-dose intra-amniotic (IA) treatment might be speculated to improve lung maturity. In the goat model, we recently showed that high-dose IA betamethasone (BM) was associated with an increased number of stillbirths and emphysematous changes. The aim of the present study is to expand our previous findings and evaluate the histopathological effects of IA injection of a single high-dose of BM 48 h before induced preterm delivery, using our previously collected specimens.

MATERIAL AND METHODS

Five hair goat fetal lungs that had received 8 mg/kg IA BM at gestational day 118 (term, 150 days) and scheduled for preterm delivery by cesarean section at day 120 of gestation were examined pathologically. Specimens were stained with hematoxylin and eosin (HE) and were interpreted by light microscopy.

RESULTS

The histopathological examination of the fetal lungs revealed edema, hemorrhage, slight inflammatory reaction, marked emphysema, and desquamation of the pneumocytes and bronchiolar or bronchial epithelial cells.

CONCLUSION

High-dose IA BM administrations to induce lung maturation can paradoxically cause severe pathological lesions in the fetal lungs. These might explain the toxic effects we encountered with this mode of treatment.