Objective: To explore the clinical features, drug resistance, treatment and prognosis of refractory urinary tract infection caused by Enterococcus faecium infection.

Methods: A retrospective analysis of 3 cases of Enterococcus faecium infection admitted to the Children’s Hospital of Shaanxi Provincial People’s Hospital from January 2017 to December 2019, And the clinical manifestations of refractory urinary tract infections caused by it, routine laboratory examinations, mid-stage urine culture and drug sensitivity, urinary ultrasound, magnetic resonance (or CT) examination, treatment process and prognosis, and search and review relevant literature.

Result: The three children in this group were all women, aged 5 years, 2 months, 9 years and 11 years old. One case had renal abscess, one case had acute pyelonephritis, and one case had bladder-ureteritis. Clinical features: 2 cases had fever with a temperature of 38-39.5°C, and children with renal abscess were accompanied by chills; 2 cases had frequent urination, dysuria, and urethral irritation; 1 case of 5-year-old child had only transient urinary retention, All 3 cases were treated with conventional antibiotics orally and intravenously outside the hospital. During the course of 2 cases, the leukocytes were more than 25×109/L, 3 cases had neutrophils above 70%, CRP was high, and 3 cases of mid-stage urine culture were Enterococcus faecium;2 cases were sensitive to vancomycin and linezolid, Others are resistant.3 cases had negative blood cultures, 1 case of urinary B-mode ultrasound had a thicker bladder wall, and a slightly thicker wall in the lower right ureter. Considering the inflammatory changes, 1 case had left hydronephrosis and 1 case had left kidney urinary salt crystals. MRI plain scan of both kidneys and ureters + MRU showed: 1 case had a thicker bladder wall, and the wall of the lower ureter was slightly thickened, considering the inflammatory changes. One case had a slight dilation of the upper left ureter and the renal pelvis and calyces. 1 case of CT enhanced scan + CTU showed: 1. Left nodular superior nodules and strip low-density shadow, considering the repeated deformity of the left renal pelvis and ureter with dilation of the ureter (upper renal pelvis is small, hypoplasia); [2]. Abnormal strengthening of the left kidney and a slight thickening of the fascia around the kidney; consider pyelonephritis with abscess formation or cystic lesions. 3. Mild water accumulation in the left kidney and upper middle ureter [4]. There are multiple lymph nodes in the retro peritoneum and the left side of the spine, and some are swollen. Treatment 3 cases were initially ineffective with three generations of cephalosporins, and 2 cases had obvious effect of intravenous infusion of vancomycin based on drug sensitivity. After 7-10 days of treatment, cefepime was changed for consolidation treatment and cured. One case of meropenem treatment improved. Three cases were followed up for 1 year without recurrence. 1 case relapsed 20 days after discharge, intravenous infusion of cefepime for 17 days, and nitrofurantoin was taken preventively for 2 weeks before relapse.

Conclusion: Most of the urinary tract infections caused by Enterococcus faecium infections are refractory upper urinary tract infections, which have many complications, timely and mid-stage urine culture, and urinary tract B ultrasound. Magnetic resonance imaging and hydrography of both kidneys and ureters play an important role in the diagnosis of complications. High drug resistance, timely adjustment of treatment according to drug susceptibility, selection of effective drugs is very important, given a sufficient course of treatment, can improve the prognosis.