Manual vacuum aspiration for postpartum pyometra

Abstract

Postpartum pyometra is rare; however, it may lead to sepsis. The main initial symptoms are fever, lower abdominal pain and foul-smelling lochia. The treatment includes antibiotic administration and surgical drainage. This is a report of postpartum pyometra following a caesarean section that was successfully treated with manual vacuum aspiration, a simple and minimally invasive option. Other treatment options include pyometra reduction using placenta forceps and the placement of an intrauterine drainage catheter.

Background

Pyometra is a uterine infection caused by the accumulation of intrauterine secretions due to cervical stenosis and obstruction. Pyometra may progress to uterine rupture and severe sepsis.^{1 2} The treatment of pyometra includes the administration of broad-spectrum antibiotics effective against both aerobes and anaerobes and appropriate drainage of the pyometra. Drainage methods include transabdominal uterine drainage and transvaginal uterine drainage using a hysterosalpingography catheter or urethral catheter. Additional treatment modalities are hysterectomy, manual vacuum aspiration (MVA) and electric vacuum aspiration (EVA). For the treatment of postpartum pyometra in this study, we employed MVA, which is commonly used for miscarriage and abortion.³

Case presentation

The patient was a primipara in her 30s who conceived via in vitro fertilisation. Her pregnancy checkups were unremarkable. She was admitted at 39 weeks of gestation following the onset of labour pains. In the latent phase of labour, fetal distress was diagnosed, and an emergency caesarean section was performed. Lochia was normal until postpartum day 5. Transvaginal ultrasonography revealed no abnormal findings, and the patient was discharged on postpartum day 6.

On postpartum day 28 during a 1 month postpartum check-up, a speculum examination revealed dark red lochia. Routine transvaginal ultrasound revealed a 6 cm diameter blood accumulation in the lower uterine lumen and methylergonovine was prescribed to be taken three times daily for 7 days. On postpartum day 42, lochia discharge was observed, and transvaginal ultrasound confirmed a mild reduction in the haematoma volume in the lower uterine lumen (figure 1). The patient was diagnosed with uterine subinvolution and delayed blood drainage from the uterine lumen and methylergonovine was again prescribed.

Figure 1.

Ultrasound image on postpartum 42 days. Haematoma seen in the lower uterine lumen.

No symptoms were observed until postpartum day 48. On postpartum day 49, the patient visited the emergency department with chief complaints of foul-smelling lochia, lower abdominal pain and fever. The temperature was 38.6°C, the leucocyte count was 14.8 × 10⁹/L and a C reactive protein (CRP) level was 13.3 mg/L. Pyometra was diagnosed, based on the symptoms, the cervical motion tenderness, the CRP level and a mixed internal echo pattern of the blood accumulated in the uterine lumen revealed by ultrasound (figure 2). Multiple treatment options were presented to the patient and informed consent was obtained. On the same day, after paracervical block, uterine drainage via MVA guided by transabdominal ultrasonography was performed in the outpatient pelvic examination room. The MVA (Women’s Health Japan, Tokyo, Japan) dilator and cannula were smoothly inserted into the cervical canal, and encapsulated abscess was drained using vacuum aspiration (figure 3). Ceftriaxone (2 g intravenously daily for 2 days) and azithromycin (500 mg orally daily for 3 days) were administered.

Figure 2.

Ultrasound finding of the encapsulated pyometra on postpartum day 49.

Figure 3.

Removal of pyometra on postpartum day 49.

Investigations

Gram staining and bacterial culture of the uterine contents drained on day 49 postpartum were performed. Gram staining of pus from the uterine cavity showed Gram-negative rods. Bacterial culture detected the anaerobe Bacteroides vulgatus. Antimicrobial susceptibility testing was performed. B. vulgatus was resistant to amoxicillin, gentamicin, cefazolin, cefotiam and clarithromycin.

Differential diagnosis

A related disease is puerperal fever. However, puerperal fever is a fever that occurs within 10 days after delivery or miscarriage.⁴ Uterine perforation is another differential, but there was no action that caused perforation during a caesarean section, and it was unlikely to cause symptoms until about 50 days after delivery. Peritonitis and appendicitis are also possible, but the localisation of tenderness to the uterus and the presence of a mass within the uterine cavity suggestive of an abscess ruled out peritonitis or appendicitis. Urinary tract infection is ruled out because no leukocytes are detected in the urine, there is no residual urine sensation, no pain during voiding and no frequent urination. In this case, the patient was treated as an intrauterine blood accumulation until postpartum day 42, but on postpartum day 49, the uterine contents became more hyperechoic, with foul-smelling lochia, lower abdominal pain and fever. Therefore, we considered postpartum pyometra rather than an intrauterine haematoma.

Retained products of conception are ruled out, as the boundary between the intrauterine abscess and the endometrium was clear, no irregularities of the endometrium were found on ultrasound examination (figures 3 and 4), and no retained tissue was detected in the drained contents. Surgical site wound infection was ruled out because there was no swelling, heat or redness of the wound, and no pus discharge was observed. Septic pelvic thrombophlebitis is a disease characterised by inflammation and thrombus formation in the pelvic veins. Historically, it was more common in the past. Recently, however, the incidence of septic pelvic thrombophlebitis has decreased markedly. In the absence of improvement despite antibiotics, septic pelvic thrombophlebitis is suspected. In this case, the patient responded promptly to broad-spectrum antibiotic therapy.

Figure 4.

No reaccumulation of pus on postpartum day 50.

Treatment

Antibiotic treatment and drainage were performed. Antimicrobial agents that are effective against both aerobic and anaerobic bacteria were selected. The antibiotics, ceftriaxone (intravenous injection 2 g once daily for 2 days) and azithromycin tablets (500 mg once daily for 3 days), were administered concurrently. Manual aspiration was used to remove the abscess.

Outcome and follow-up

The fever subsided on the day of uterine drainage. The anaerobe B. vulgatus was isolated from the bacterial culture of uterine contents. On postpartum day 50 (day 1 after the uterine drainage), her abdominal pain and cervical tenderness disappeared. Blood tests revealed a leucocyte count of 7.2 × 10⁹/L and a CRP level of 0.67 mg/L. There was no relapse afterwards (figure 4).

Discussion

Transvaginal uterine drainage via MVA is effective for pyometra and can be performed easily and safely. The cervical canal may narrow quickly after pyometra drainage, causing a relapse, and a drainage catheter may need to be placed in the uterus for an extended period of time. The insertion procedure for drainage that places a hysterosalpingogram catheter or urethral catheter without cervical dilation is easy; however, the catheter’s diameter is small and its lumen may become blocked. In addition, because aspiration is not performed, drainage may not be fully effective. On the contrary, because MVA can evacuate the uterus in a single procedure, drainage efficiency is high. In addition to a cannula that is inserted into the uterine lumen, the women’s MVA system (Women’s Health Japan) includes a cervical dilator that can widen the cervical canal to prevent cervical reobstruction. In this case, the symptoms of postpartum pyometra were promptly relieved by MVA, and the infection did not recur. B. vulgatus is generally considered to be a beneficial gut commensal, making up to 30% of the total colonic bacteria. The low pathogenicity of the bacteria recovered from the clot and the prompt response to infection despite a suboptimal antibiotic regimen suggests that the infection involved only the intrauterine clot and that it did not extend deeply into the uterine myometrium.

In our case, we selected MVA for uterine drainage, but the choice of EVA is also available. MVA is more portable, less expensive, clean, quiet, does not require electricity.^{5 6} The plastic cannula used in MVA is less likely to damage the endometrial basal layer due to its adequate stiffness and high flexibility.⁶ There are preliminarily reports on MVA for the evaluation and treatment of retained products of conception (RPOC).⁷ Furthermore, MVA has been applied to endometrial biopsies,⁸ and future studies on expanding the indications for MVA may be reported. For abnormal postpartum bleeding, it has been reported that haemostasis was achieved by removing haematomas using an aspirator and inducing uterine contractions,⁹ and aspiration could be effective when there was a large haematoma or abscess in the uterine lumen.

Patient’s perspective.

On day 49 postpartum, I experienced the harsh smell of my discharge, discomfort when urinating, low abdominal pain, and fatigue. I had little pain from the drainage procedure because I was given a local anesthesia prior to the procedure. After the drainage, the drained uterine contents smelled very bad. The fever went down the day after drainage.

Learning points.

• Pyometra is a differential diagnosis for postpartum fever.

• The pathogenic bacteria of postpartum pyometra may be anaerobes.

• Manual vacuum aspiration can be easily and safely performed under the guidance of transabdominal ultrasonography.

• Vacuum aspiration is also effective for encapsulated abscesses.

• Pyometra drainage and antibiotic administration prevent the development of sepsis.

Ethics statements

Patient consent for publication

Consent obtained directly from patient(s).