Pelvic inflammatory disease due to Streptococcus pneumoniae

Dear Editor,

Invasive pneumococcal disease is the most serious form of disease produced by Streptococcus pneumoniae, especially affecting those under 5 and over 65 years of age. It is considered an invasive pneumococcal disease to the isolation and detection of the antigen or nucleic acid of S. pneumoniae in a normally sterile location.¹ Pneumonia is the most frequent form of clinical presentation, with an incidence rate of around 6 cases out of 10² inhabitants in the Valencian Community,³ followed by bacteraemia without focus and meningitis.⁴ Other less frequent forms of clinical presentation are: spontaneous bacterial peritonitis, arthritis and pelvic inflammatory disease (PID), among others.⁴

We present the case of a 37-year-old patient who went to A&E due to a 3-day history of abdominal pain and fever, without urinary syndrome or alterations of the intestinal rhythm. Her history included two pregnancies and two deliveries, the last of which was two years before with postpartum subtotal hysterectomy due to placenta accreta. On physical examination, the patient presented with a soft, depressible and painful abdomen on palpation. The gynaecological examination showed yellow, non-malodorous vaginal discharge and pain with pressure in the recto-uterine pouch. In the transvaginal ultrasound, a heterogeneous image of 54 × 33 mm, in “gear wheel”, compatible with right Fallopian tube, and another heterogeneous image of 57 × 27 mm in left appendage. Blood analysis showed elevated C-reactive protein (124.8 mg/l) and neutrophilia. The patient was admitted to the Gynaecology Department with empirical intravenous antibiotic therapy, including cefotaxime, metronidazole and doxycycline due to suspected PID. A CT scan was requested where suspicion of an abscess due to ovarian tube persisted, so a laparotomy was performed, confirming the findings and performing right salpingectomy and left adnexectomy. In addition, an intraoperative sample was obtained for a long incubation bacteriological culture. The DNA detection of Chlamydia trachomatis and Neisseria gonorrhoeae was negative, as well as the culture of genital mycoplasmas. After 24 hours of incubation, mucous alpha haemolytic colonies grew in the vaginal bacteriological culture in pure culture in the blood agar plate and in the chocolate agar plate, observing gram-positive cocci in chains in the long incubation culture stain. Growth of S. pneumoniae was reported, identified with VITEK MS (bioMérieux, Marcy-l’Étoile, France). The sensitivity study was carried out by disk diffusion, being sensitive to cotrimoxazole, erythromycin, levofloxacin, vancomycin and imipenem and with E-test an MIC of 0.008 μg/ml of ceftriaxone and 0.016 μg/ml of penicillin was observed. After agglutination with antisera (Statens Serum Institut, Copenhagen), serotype 3 was obtained, which fits with the macroscopic characteristics of the colony. The patient was discharged 24 hours after admission with oral levofloxacin.

The natural microhabitat of pneumococcus is the human nasopharynx, transmitted mainly through respiratory droplets. Infants and young children are the main reservoir of this agent, although colonised adults may also be used.⁵S. pneumoniae is not part of the usual vaginal microbiota, being isolated in the vaginal discharge in less than 1% of women,² meaning that cases of PID by pneumococcus are anecdotal. However, pneumococcus can access the vaginal mucosa due to contamination from the hands or oral-genital sexual practice.⁶ Some of the factors that favour colonisation are: having an intrauterine device, use of tampons, recent gynaecological surgery and the postpartum, post-abortion and puerperium periods.⁷ These conditions produce changes in the vaginal pH, temporarily allowing pneumococcus to exist as a commensal microbiota, although it can sometimes be complicated and evolve to peritonitis.⁸ Other possible routes of access of pneumococcus to the genital tract may be the haematogenous spread and transmural infection through the gastrointestinal tract, which is infrequent since pneumococcus is rarely intestinal commensal. The clinical cases described in the literature agree that the most common form of clinical presentation is abdominal pain with predominance in the hypogastrium, increased vaginal discharge and fever. When PID is suspected, empirical antibiotic treatment based on levofloxacin, ceftriaxone, doxycycline and/or metronidazole should be given to cover the most frequently involved pathogens, and to avoid significant sequelae, as was done in this patient. The detection of pneumococcus and early treatment is necessary, since in many cases it can lead to a serious, complicated and potentially fatal septic event.⁹