Candidate predictor | Definition | Units/categories |
---|---|---|
(a) Measured at admission | ||
Demographic | ||
Age | Recorded age at hospital admission in 10-year age bands (continuous age is unavailable due to privacy regulations) | 18–24, 25–34,…, 95–104 |
Sex | As recorded in the admission notes | Male/female |
Social deprivation | Index of Multiple Deprivation (IMD) 2015 quintile | Deciles (1–10) |
Ethnicity | As recorded in the admission notes; collapsed into 5 major categories | Asian, Black, Mixed, other, White |
Co-morbidity | ||
Charlson Co-morbidity Index | Numeric comorbidity score based on the presence of relevant ICD-10 codes in the entire hospital record* | Count (1–33) |
Underlying renal disease | Presence of a relevant ICD-10 code in the previous 5 years* | Yes/no |
Underlying urological condition | Presence of a relevant ICD-10 code in the previous 5 years* | Yes/no |
Renal or urological surgery | Presence of a relevant OPCS code in the previous 5 years* | Yes/no |
Immunosuppression | Presence of a relevant ICD-10 code in the prior year* | Yes/no |
Cancer | Presence of a relevant ICD-10 code in the prior year* | Yes/no |
Previous healthcare contact | ||
Discharge from hospital in prior 7 days | Most recent discharge date from QEHB within 7 days of index attendance date | Yes/no |
Number of previous admissions | Number of hospital spells at QEHB in the prior year | Count (≥ 0) |
Number of days spent in hospital | Number of days spent as an inpatient at QEHB in the prior year | Count (≥ 0) |
Number of previous ED attendances | Number of ED attendances at QEHB in the prior year | Count (≥ 0) |
Factors predisposing to UTI | ||
Previous admission for UTI | Admission to QEHB with an ICD-10 code of UTI on discharge in the prior year* | Yes/no |
Previous ED attendance for UTI | ED attendance at QEHB with ED diagnosis of lower UTI, pyelonephritis or urosepsis in the prior year | Yes/no |
Number of previous admissions for UTI | Number of hospital spells at QEHB with an ICD-10 code of UTI on discharge in the prior 2 years* | Count (≥ 0) |
Number of previous ED attendances for UTI | Number of ED attendances at QEHB with ED diagnosis of lower UTI, pyelonephritis or urosepsis in the prior year* | Count (≥ 0) |
Previous urine culture | Urine sample submitted at QEHB for microbiological diagnosis in prior year | Yes/no |
Previous bacteriuria | Urinary pathogen identified at QEHB from blood or urine in prior year | Yes/no |
Previous resistant pathogen | Drug-resistant pathogen identified at QEHB from blood or urine in prior year | Yes/no |
Prior antibiotic consumption | Total antibiotic consumption in QEHB in prior year | Defined daily doses (DDDs) (≥ 0) [18] |
Characteristics of the admission | ||
Admitted from care home | As recorded | Yes/no |
Month of admission | As recorded | January,…, December |
Day of year of admission | As recorded | Count (1–366) |
Day of week of admission | As recorded | Monday,…, Sunday |
Investigations in the ED | ||
Suspected diagnosis in the ED | ED impression of clinical syndrome as recorded by the ED clinician | Lower UTI, pyelonephritis, urosepsis |
Positive urinalysis | Presence of leucocytes and/or nitrates in urinalysis | Yes/no |
Urinalysis | ||
Leucocytes | As recorded by the clinician (dipstick test) | Positive/negative |
Nitrates | As recorded by the clinician (dipstick test) | Positive/negative |
White blood cells | As recorded by the laboratory (flow cytometry) | Count/μL |
Red blood cells | As recorded by the laboratory (flow cytometry) | Count/μL |
Epithelial cells | As recorded by the laboratory (flow cytometry) | Count/μL |
Small round cells | As recorded by the laboratory (flow cytometry) | Count/μL |
Bacteria | As recorded by the laboratory (flow cytometry) | Count/μL |
Yeast | As recorded by the laboratory (flow cytometry) | Count/μL |
Conductivity | As recorded by the laboratory (flow cytometry) | mS/cm |
Casts | As recorded by the laboratory (flow cytometry) | Count/μL |
Crystals | As recorded by the laboratory (flow cytometry) | Count/μL |
(b) Measured multiple times throughout hospital stay† | ||
Clinical observations | ||
Heart rate | As recorded | Beats per minute |
Respiratory rate | As recorded | Breaths per minute |
Body temperature | As recorded | C° |
Oxygen saturation | As recorded | Percent |
Systolic blood pressure | As recorded | mmHg |
AVPU | As recorded | Alert, verbal, pain, unresponsive |
SEWS | Standardised Early Warning Score as recorded or calculated based on heart rate, respiratory rate, body temperature, oxygen saturation and AVPU | Count (0–18) |
Clinical investigations | ||
White cell count (blood) | As recorded | 103/mL |
C-reactive protein | As recorded | mg/L |
Creatinine | As recorded | μmol/L |
Acute kidney injury score | Defined as the change in serum creatinine compared to an approximate baseline measure (i.e. average creatinine in previous 6 months) | Stage 0 (1.0–1.5 × baseline), stage 1 (1.5–1.9), stage 2 (2.0–2.9) stage 3 (≥ 3.0) |
Alkaline phosphatase | As recorded | IU/L |
Bilirubin | As recorded | μmol/L |
Platelets | As recorded | 109/L |
Antibiotic treatment | ||
Antibiotic treatment | Recorded administration of any systemic antibiotic (British National Formulary chapter 5.1.‡) | Yes/no |
Broad-spectrum antibiotic | Recorded administration of any of the following antibiotics: co-amoxiclav, piperacillin-tazobactam, carbapenems, cephalosporins (except 1st generation), quinolones, colistin, fosfomycin, aminoglycosides | Broad-spectrum, narrow-spectrum, none |
Route of administration | Recorded route of administration, giving precedence to intravenous (IV) antibiotics (i.e. if multiple antibiotics are prescribed with ≥ 1 IV, treatment is classified as IV) | IV, oral, none |
Dosage | As recorded | DDDs (≥ 0) [18] |