A 45-year-old man was presented at the emergency department with altered neurological status and a 1-day history of diarrhoea and fever. The patient’s sexual history revealed multiple male partners. As bacterial meningitis or viral encephalitis was suspected, treatment was started accordingly. Cerebrospinal fluid investigations only showed a slight increase of leucocytes, and microbiological studies remained negative. Stool culture revealed Shigella flexneri, after which Shigella-associated encephalopathy was suspected. The patient recovered quickly with antibiotic treatment. The incidence of Shigella infections in the Western world is rising due to sexual transmission among men who have sex with men. Shigella-induced encephalopathy is a notorious complication among children with a severe form known as the Ekiri syndrome, though rarely seen in adults. This is the second report of encephalopathy in an adult with S. flexneri enteric infection.

Vaginal microbiota composition is associated with spontaneous preterm birth (sPTB), depending on ethnicity. Host-microbiota interactions are thought to play an important underlying role in this association between ethnicity, vaginal microbiota and sPTB. We aimed to further elucidate the association between vaginal microbiota, host-microbiota interactions and sPTB. We studied populations with different risk stratification for sPTB to investigate the role of population characteristics and chartered unknown territory by investigating the association between vaginal microbiota and local immunoglobulins (Igs). In nulliparous women, with low risk for pregnancy complications, we found a strong association between Lactobacillus iners dominated and diverse microbiota and sPTB. While in multiparous women with a previous sPTB, with high risk for recurrence, we did not find an association between vaginal microbiota and sPTB. We found an association between microbial IgA and IgG coating and microbiota composition, with higher microbial immunoglobulin coating in Lactobacillus dominant microbiota. However, we did not find evidence that immunoglobulin coating is associated with preterm birth. Also, in a systematic review and meta-analysis we found that asymptomatic vaginal yeast colonization is not associated with sPTB. In conclusion, we investigated several aspects related to the role of vaginal microbiota and host-microbiota interaction in relation with preterm birth. Vaginal microbiota and sPTB seems only associated in specific populations. And while not associated with sPTB, our results suggest that vaginal mucosal Igs might play a pivotal role in microbiota composition. Future research should focus on prediction of sPTB using vaginal microbiota in nulliparous women, microbiota and immune modulation in pregnant women to prevent sPTB and the role of vaginal immunoglobulins in health and disease.