Medha Narwankar

Introduction. Pelvic inflammatory disease (PID) is a broad spectrum of reproductive tract infections that can cause inflammation and damage to fallopian tubes^1,2. The endometrial microbiome creates a biofilm and dynamic interface that supports interaction between gametes, the embryo, and maternal tissue³. Statistics have shown that 2.5 million reproductive-aged women have reported PID, of which 15% develop infertility⁴. PID ultimately impairs the endometrial epithelium which leads to poor gamete transport and interaction during fertilization, increasing the risk of infertility^1,3. Patients present asymptomatically during the acute stages of PID and diagnosis requires symptomatic proof which is usually confirmed when the disease becomes chronic, causing symptoms of pelvic pain, vaginal discharge, fever, and irregular bleeding^4,5. Methods. Comparison of the endometrial microbiome between a normal (control) patient and one diagnosed with PID was used to identify the bacteria responsible for infection^6,7. This set of pathogens was used to train a machine learning model to screen endometrial samples collected from patients for PID^6,7. Subjects were also screened every 4 months and compared to those screened every 3 years as guidelines suggest in order to analyze development of comorbidities such as infertility⁸. Vaginal microbiome transplantation was studied in patients with a history of recurrent or antibiotic-resistant bacterial vaginosis as a means for treatment⁹. Results. Identification of the endometrial microbiome in a patient with PID consists of varying levels of Dialister, Bifidobacterium, Prevotella, Gardnerella, and Anaerococcus taxa when compared to control patients^6,7. Studies showed a significant correlation between these pathogens and comorbidities associated with PID such as infertility, which were decreased in patients who were more periodically screened⁸. Vaginal microbiome transplantation in patients with bacterial vaginosis proved to be successful in clearing inflammatory cells and restoring the microbiome⁹. Conclusions. Current gaps with PID diagnosis and care involve timely screening, repair of scarred tissue, and restoration of the endometrial microbiome. Damaged tissue that results due to chronic inflammation has to be surgically repaired if the goal is to return the tissue back to a healthy state. Antibiotics simply treat the infection, but relapse may occur due to antibiotic driven clearance of protective microbes necessary for optimal function⁹. To diagnose PID in its more acute stages preventing chronic comorbidities, annual bacterial screening should be conducted. If a patient tests positive, their endometrial tissue should be assessed for damage and surgical repair utilized as needed. For sustained treatment and restoration of dysfunctional tissue, endometrial microbiome transplantation can be done.

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