Rate and characteristics of infection after transrectal prostate biopsy: a retrospective observational study

Figures & data

Figure 1. Identification of patients with infection after biopsy. Data on primary care visits for reasons unrelated to post-biopsy infection was not collected. ED: emergency department; PO: per oral; TRbx: transrectal prostate biopsy.

Table 1. Patient characteristics and potential risk factors.

	Total	No infection	Infection
Total, n	670	634	36
Helsingborg^a	430	409	21
Ängelholm^b	240	225	15
Age, median years (range)	69 (42–91)	69 (42–90)	68 (52–91)
Prostate size, median cm^c (range)	44 (11–190)	44 (11–190)	51 (17–127)
PSA, median µg/l (range)	7.0 (0.3–2037)	7.0 (0.3–2037)	7.0 (3.6–375)
Pathology diagnosis, n (%)
No cancer	269 (40%)	253 (40%)	16 (44%)
Cancer	401 (60%)	381 (60%)	20 (56%)
Diabetes, n (%)	78 (12%)	68 (11%)	10 (28%)
Immunosuppression^c, n (%)	28 (4.2%)	27 (4.3%)	1 (2.8%)
Hypertension, n (%)	274 (41%)	257 (40%)	17 (47%)
Other significant comorbidity^d, n (%)	156 (23%)	141 (22%)	15 (42%)
Previously biopsied, n (%)	257 (39%)	242 (38%)	15 (43%)

^a Biopsies were obtained using Mermaid Medial M-biopsy 18 Gauge 25 cm tru-cut biopsy needles with Möller Medial Blue Biopsy Gun RBG-1000. BK ultrasound with single-use biopsy guide on transducer.

^b Biopsies were obtained using Argon medical 18 Gauge 25 cm Pro-Mag tru-cut biopsy needle with Argon medical Pro-Mag Ultra Automatic Biopsy Instrument. BK ultrasound with single-use biopsy guide on transducer.

^c More than 5 mg prednisolone or equivalent.

^d Heart failure, cardiac arrhythmias, previous heart attack, chronic obstructive pulmonary disease, or kidney failure.

Table 2. Infection characteristics.

Characteristics	Outcome
Number of patients with post biopsy infections, n (% of total patients; 95% CI)	36 (5.4%; 3.7–7.1%)
Patients not hospitalized, n (% of total with infections; 95% CI)	10 (28%; 13–42%)
Patients hospitalized once, n (% of total with infections; 95% CI)	17 (47%; 31–64%)
Patients hospitalized and requiring multiple hospitalizations/ED visits, n (% of total with infections; 95% CI)	9 (25%; 11–39%)
Admitted to hospital after initial PO antibiotic treatment, n (% of total with infections; 95% CI)	3 (8.3%; 0–17.4%)
Developed infection while hospitalized, n (% of total with infections; 95% CI)	2 (5.6%; 0–13%)
Total patients hospitalized with infection, n (% of total patients; 95% CI)	26 (3.9 %; 2.4–5.3%)
Hospitalized within 48 h of TRbx, n (% of hospitalized patients; 95% CI)	15 (58%; 39–77%)
Hospitalized within 7 days of TRbx, n (% of hospitalized patients; 95% CI)	24 (92%; 82–100%)
Duration of hospitalization, median days (range)	5 (2–14^a)
Duration of hospitalization, mean days (used in economic calculations)	6
Peak CRP,^b median (range)	164 (9.4–442)
Antibiotic treatment duration,^c median days (range)	12.5 (5–63)
Required IV antibiotics, n (% of total with infections; 95% CI)	24 (67%; 51–82%)
Treatment duration, median days (range)	4 (2–12)
SOFA score ≥ 2, n (% of total with infections; 95% CI)	5 (14%; 2.6–25%)
ICU treatment, n (% of total with infections; 95% CI)	1 (2.8%; 0–8.1%)
Deaths due to post-biopsy infection, n (% of total with infections)	0^d (0%)

^a The patient hospitalized for 14 days was treated for stroke and dyspnea in addition to post-biopsy infection.

^b The venous CRP was not continuously measured for one patient and for this reason the low range value is likely an underestimation.

^c Treatments received at the ED or hospital and including available data from the primary care.

^d One elderly patient not classified as having a post-biopsy infection was found dead at home 12 days after biopsy. Cause of death unknown.

ED: emergency department; CRP: c-reactive protein; IV: intravenous; PO: per oral; SOFA: sequential organ failure assessment; ICU: intensive care unit; 95%CI: 95% confidence intervals.

Table 3. Bacteria found in blood and urine cultures.

Bacteria	Any positive culture (n = 28)	Urine culture (n = 26)	Blood culture (n = 9)
E. coli	23	21	8
Ciprofloxacin resistant	14	12	5
TMP-SMX resistant	9	8	1
ESBL	3	3	0
Klebsiella pneumoniae	3	3	1
Citrobacter koseri	1	1	0
Enterobacter cloacae and enterococcus faecalis	1	1	0

TMP-SMX: Trimethoprim/sulfamethoxazole; ESBL: extended spectrum beta-lactamase.

Table 4. List of ICD-10 codes at hospital discharge given to patients with post-biopsy infection at the first hospitalization.

Type of code	Patients (n)	ICD-10 code	Description
Sepsis, total	5
Sepsis	2	A41.5	Sepsis due to other Gram-negative organisms
Sepsis	2	A41.9	Sepsis, unspecified organism
Sepsis	1	R65.1	Sepsis, severe, as a result of disease classified elsewhere
Infection, total^a	15
Infection	3	N10	Acute tubulo-interstitial nephritis
Infection	7	N39.0	Urinary tract infection, site not specified
Infection	1	N41.0	Acute prostatitis
Infection	1	N45.9	Orchitis, epididymitis and epididymo-orchitis without abscess
Infection	2	T81.4	Infection following a procedure, not elsewhere classified
Infection	1	R50.9	Fever, unspecified
Unspecified, total	1
Unspecified	1	T81.8 + Y83.8	Other complications of procedures, not elsewhere classified + Other surgical procedures
Cancer, total	2
Cancer	1	C61	Malignant neoplasm of prostate
Cancer	1	C23	Malignant neoplasm of gallbladder
Internal medicine, total	3
Internal medicine	1	I50.9	Heart failure, unspecified
Internal medicine	1	I63.9	Cerebral infarction, unspecified
Internal medicine	1	I26.0	Pulmonary embolism with mention of acute cor pulmonale
Total number	26

^a Not including sepsis.

One infection-related ICD-10 code at discharge per patient is presented when applicable. If an infection-related code was not given then the primary ICD-10 code is presented here. (All patients who were readmitted to hospitals within Region Skåne received an infection-related code at readmission that is not presented here, please see supplementary table 2.)