Spontaneous uterine perforation of pyometra leads to acute abdominal pain and septic shock: a case report

Dear editor,

Uterine pyometra is a rare disease that mostly affects elderly women and is usually asymptomatic. Pyometra is defined as an accumulation of pus in the uterine cavity caused by genital tract malignancy or benign cervical diseases such as senile cervicitis, cervical polyps, or remaining intrauterine devices after menopause.[1] The incidence of spontaneous uterine perforation due to pyometra is extremely low, ranging from 0.01% to 0.05%.[2] Although it has low morbidity, it can progress to diffuse peritonitis, and the mortality rate associated with septic shock is as high as 25%–40%.[3] It is still difficult for emergency doctors to provide an accurate diagnosis and perform surgery on time. Here, we present a rare case of a 72-year-old woman who was diagnosed with spontaneous uterine perforation of pyometra and successfully treated with an emergency laparotomy.

CASE

We present the case of a 72-year-old postmenopausal woman with a history of hypertension and diabetes mellitus who complained of decreased urination for more than 20 d. She complained of chest pain and shortness of breath over the last two days without obvious signs of abdominal pain or distension. She visited a local hospital for an abdominal computed tomography (CT) scan, which revealed an enlarged uterus with air and fluid inside the cavity. She was admitted to our emergency department one day ago due to aggravation that included high fever and obnubilation. Her laboratory tests revealed an elevated neutrophil percentage and C-reactive protein levels at 95.1% (normal range 50.0%–70.0%) and 284.3 mg/L, respectively. The procalcitonin level was higher than 100 ng/mL (normal range <0.5 ng/mL), and her body temperature was 38.5 °C. Her heart rate was irregular with 100–130 beats/min, and her blood pressure was approximately 80/40 mmHg (1 mmHg=0.133 kPa). The patient underwent a blood next-generation sequencing test, which revealed the causative organism of the infection as Bacteroides fragilis. She received positive antishock therapy due to her severe septic shock, including intravenous antibiotics (imipenem and cilastatin, 0.5 g, every 8 h). Simultaneously, another abdominal CT scan was performed, revealing a cystic solid density shadow with calcification in the right adnexal region, as well as free air and a possible large infectious lesion inside the mass (Figure 1). Due to her uterine pyometra-induced septic shock, an emergency laparotomy was performed. During the surgery, approximately 200 mL of purulent secretion was present in the pelvic cavity, as well as pus on the surface of the colon and ileum, which was strongly adhered to the uterine and lateral pelvic wall. The uterus had increased in size similar to a 2-month pregnancy, in which the anterior and posterior wall surfaces covered black necrotic tissue, forming the pus cavity with an obvious peculiar smell. Furthermore, there was right fallopian tube enlargement, which was densely adherent to the surrounding tissue and had pus moss on the surface. The perforation at the fundus of the uterus was discovered after the hysterectomy, and bilateral salpingo-oophorectomy was performed (Figure 2). Histological examination revealed that the uterine mucosa had erosion and ulceration, resulting in necrosis and abscess formation. A large number of acute and chronic inflammatory cells infiltrated the muscle wall confirming pyometra, and there was no evidence of cervical malignancy shown both in histological examination and radiation examination. The culture of pus indicated the presence of Escherichia coli postoperatively.

Figure 1.

The image of abdominal computed tomography scan. Free air inside the cavity (white arrow).

Figure 2.

The perforation located at the fundus of the uterus (white arrow).

The patient was admitted to the intensive care unit to continue intravenous antibiotics and sepsis treatment postoperatively. After careful management of circulation and respiration, her condition improved, and her body temperature returned to normal. She was transferred to a general unit on the 9^th postoperative day. Her antibiotics were changed from imipenem and ornidazole to tazocin three days after her temperature was stable. She eventually recovered and was discharged on the 21^st postoperative day after providing informed consent.

DISCUSSION

Pyometra patients have much less uterine perforation. Although it is a rare condition, it is associated with a high risk of morbidity and mortality. Approximately half of ruptured pyometra patients have a poor prognosis when they arrive at emergency care with sepsis shock, generalized peritonitis, renal failure, or other severe diseases. Because a significant number of unruptured pyometra patients have nonspecific symptoms[4,5] when it comes to rupture, most patients complain of lower abdominal pain, vomiting, and fever. Therefore, they may be misdiagnosed as gastrointestinal perforation. Moreover, an accurate diagnosis is difficult until the operation is underway. Lower abdominal pain, vaginal bleeding after menopause, and purulent vaginal discharge are typical symptoms of pyometra. Pyometra can be caused by malignancy or benign tumors, endometrial polyps, senile cervicitis, radiotherapy, and other factors.

Escherichia coli and Bacteroides species were the most common etiological organisms.[6] Klebsiella, Streptococcus, Staphylococcus, Acinetobacter, Porphyromonas, Enterococcus, and Actinomyces species are among the other causative microorganisms. These gas-producing microbes may be responsible for the presence of gas in the uterine cavity, which is strong evidence for the diagnosis of spontaneous uterine perforation.

The treatment of spontaneous uterine perforation of pyometra includes broad-spectrum antibiotics against aerobic and anaerobic conditions and timely medical intervention.[7] Hysterectomy is the typical choice, but in some cases, a total hysterectomy with bilateral salpingo-oophorectomy is needed. To support the patient postoperatively, it is critical to have thorough drainage of the pelvic cavity, as well as intensive care. Management of total hysterectomy with bilateral salpingo-oophorectomy is essential. For the successful treatment of spontaneous uterine perforation of pyometra, controlling the infectious source is imperative.

CONCLUSION

Spontaneous uterine perforation is an extremely rare disease in postmenopausal women that cannot be accurately diagnosed until surgery is performed. This diagnosis should be considered for elderly women who complain of lower abdominal pain and show symptoms of peritonitis to help the patient receive proper treatment and reduce mortality.