A midstream urine collector is not a good alternative to a sterile collection method during the diagnosis of urinary tract infection

The position during urine sample collection from young precontinent children through a bag does not limit contamination rates: Results from a randomized controlled trial: Does infant position influence quality of urine collection?

AIM

Despite its limitation, bag collection is still widely used for a preliminary urine screening test in non-toilet-trained children suspected of febrile urinary tract infection. A previous study conducted by our group raised the hypothesis that the absence of direct contact between urine and the perinea during urine collection could limit urine contamination by perineal flora. The aim of this study was to evaluate the impact of the patient's position during urine collection (upright standing position versus free position) on the rate of contaminated urine samples in non-toilet-trained children with suspected febrile urinary tract infection.

METHODS

This prospective, randomized, controlled study took place in seven pediatric emergency departments. Two groups were compared: the intervention group (infants held in an upright standing position during urination) and the control group (free position during urination).

RESULTS

Among the 800 pediatric patients randomized to the study, 124 had a urine culture, 60 in the intervention group and 64 in the control group. Among the 124 urine cultures, 12 (9.7%) were contaminated: eight (13.3%) in the intervention group and four (6.3%) in the control group (p = 0.1824).

CONCLUSION

The results show that the patient's position does not have a significant impact on the quality of urine samples collected by bag.

Outpatient urine collection methods for paediatric urinary tract infections: Systematic review of diagnostic accuracy studies

AIM

To investigate the diagnostic test accuracy of urine collection methods for urinary tract infections in outpatient children.

METHODS

A systematic literature review until April 2021 (Medline, Web of Science, Embase, Cinahl) to examine the diagnostic test accuracy of urine culture on collection methods for urinary tract infection in outpatient children below 18 years. Contamination rates were studied as secondary outcome. The risk of bias was assessed using the QUADAS-2 criteria. Two-by-two tables were extracted in duplicate to calculate sensitivities, specificities, and likelihood ratios with 95% confidence intervals.

RESULTS

The search identified seven relevant studies. Clean catch compared to catheterization in children less than 90 days showed a sensitivity and specificity of 97% and 89% (95% CI: 84%-100% and 67%-99%), respectively. Adhesive bags compared to catheterization showed a sensitivity of 83% (95% CI: 75%-90%) and specificity of 91% (95% CI: 83%-96%). There was a similar diagnostic accuracy when comparing urine sampling by means of adhesive bags versus nappy pads. The contamination rate was 5% for clean catch, 30%-80% for adhesive bags and 64% for nappy pads.

CONCLUSION

Nappy pads and adhesive bags are easy to use with comparable accuracy but are extremely prone to contamination. Clean-catch urine sampling might be an accurate alternative in young infants in ambulatory care.

Design of a novel midstream fluid waste sample collection device for patients

Reducing the contamination rates in mid-stream urine samples is a challenge. A novel design for a mid-stream urine sample collection device, which uses a novel mechanism to separate the mid-stream flow from the fore-stream and end-stream flows based on flow speed, is presented. The device, supplied in two parts, is designed to be clipped to a toilet and used in a seated position, which improves ease of use for disabled patients. As there is no mixing of the flow types during use, it is hypothesised that contamination rates should be lower than many competing designs. The all-polymer design is easy to use by both men and women, due to the addition of a form-fitting funnel and is designed to collect samples directly into containers of the same standard currently issued, allowing easy and hygienic collection. Due to its complex shape, the main body of the device is produced by a non-conventional injection moulding process. The holder can be produced using standard injection moulding technology. The two parts are designed to be assembled together by the user by means of a simple interference fit, which removes the cost of assembly altogether.

Urinary Tract Infection in Children

BACKGROUND

Urinary Tract Infection (UTI) is a common infection in children. Prompt diagnosis and appropriate treatment are very important to reduce the morbidity associated with this condition.

OBJECTIVE

To provide an update on the evaluation, diagnosis, and treatment of urinary tract infection in children.

METHODS

A PubMed search was completed in clinical queries using the key terms "urinary tract infection", "pyelonephritis" OR "cystitis". The search strategy included meta-analyses, randomized controlled trials, clinical trials, observational studies, and reviews. The search was restricted to English literature and the pediatric age group. Patents were searched using the key terms "urinary tract infection" "pyelonephritis" OR "cystitis" from www.google.com/patents, http://espacenet.com, and www.freepatentsonline.com.

RESULTS

Escherichia coli accounts for 80 to 90% of UTI in children. The symptoms and signs are nonspecific throughout infancy. Unexplained fever is the most common symptom of UTI during the first two years of life. After the second year of life, symptoms and signs of pyelonephritis include fever, chills, rigor, flank pain, and costovertebral angle tenderness. Lower tract symptoms and signs include suprapubic pain, dysuria, urinary frequency, urgency, cloudy urine, malodorous urine, and suprapubic tenderness. A urinalysis and urine culture should be performed when UTI is suspected. In the work-up of children with UTI, physicians must judiciously utilize imaging studies to minimize exposure of children to radiation. While waiting for the culture results, prompt antibiotic therapy is indicated for symptomatic UTI based on clinical findings and positive urinalysis to eradicate the infection and improve clinical outcome. The choice of antibiotics should take into consideration local data on antibiotic resistance patterns. Recent patents related to the management of UTI are discussed.

CONCLUSION

Currently, a second or third generation cephalosporin and amoxicillin-clavulanate are drugs of choice in the treatment of acute uncomplicated UTI. Parenteral antibiotic therapy is recommended for infants ≤ 2 months and any child who is toxic-looking, hemodynamically unstable, immunocompromised, unable to tolerate oral medication, or not responding to oral medication. A combination of intravenous ampicillin and intravenous/intramuscular gentamycin or a third-generation cephalosporin can be used in those situations. Routine antimicrobial prophylaxis is rarely justified, but continuous antimicrobial prophylaxis should be considered for children with frequent febrile UTI.

Clean catch urine collection: Time taken and diagnostic implication. A prospective observational study

AIM

Clean catch urine (CCU) collection is commonly used in pre-continent children. CCU can be time-consuming and specimens may be contaminated. Our aim was to determine the time taken for CCU attempts and to describe the success of this method in diagnosing or excluding urinary tract infection.

METHODS

Prospective observational study of CCU in pre-continent children aged 2-48 months in the emergency department. Time taken until urine collection, 'successful' (voided and caught), 'missed' (voided not caught) or the procedure 'stopped', were recorded and urine culture results analysed.

RESULTS

Two hundred and seventeen children (131 (60%) male) were enrolled. There were a total of 247 attempts at CCU. For the first attempt, the median collecting time was 30.5 min (interquartile range (IQR) 11-66). Outcome was 'successful' in 64% (95% confidence intervals (CI) 58-70%), 'missed' in 16% (95% CI 11-20%) and 'stopped' in 20% (95% CI 15-26%). Median time if 'successful' was 25 min (IQR 7-46.5), 'missed' 27 min (IQR 11.6-59) and 71 min (IQR 42.5-93) when 'stopped'. One hundred and sixty children had successful CCU collection, 129 were sent for culture. Fifty of 129 (39%) cultures were contaminated. If all urine specimens caught were sent for culture, the estimated yield of an uncontaminated urine specimen was 45%. Contamination was not related to time taken for CCU.

CONCLUSIONS

CCU is time-consuming, frequently unsuccessful and contaminated, resulting in a low overall diagnostic yield. Clinicians could expect a 45% chance of obtaining a definitive urine sample from this method overall.