UTI and clinical examination – what’s useful?
Medical students and young doctors are encouraged to ensure they have examined the patient at every opportunity. When it comes to rectal examination the surgeons still enjoy trotting out the hoary mantra: put your finger in it or put your foot in it. The excellent Des Spence (prolific blogger as well as esteemed BMJ columnist) has recently covered the issue of rectal examination and pelvic examination – both intimate examinations with an occasionally dubious evidence base.
We all have anecdotal experience where examination has magically highlighted the diagnosis; these tend to be rare but memorable professional experiences. They stand out in glorious technicolour against the grey background of countless negative findings. I’ve always suspected the predictive value for most examinations is dire.
Last week, I was teaching year two medical students about UTIs – I floundered as I encouraged them to pop a hand on the abdomen then realised this isn’t necessarily what I do. My first priority when I see someone (usually female) with a suspected UTI is to get a urine sample from them. As often as not, given most women have a fair idea what’s going on, they’ll proudly produce, often with a dramatic flourish, a jam-jar full of wee. Great. I dip it and we decide how we are going to manage things. Unless some other factor points suggests otherwise I will often miss out any further examination.
The predictive value of examination is often ignored and has little impact on how we teach students. The study in BMC Family Practice, Does clinical examination aid in the diagnosis of urinary tract infections in women? A systematic review and meta-analysis, looked at this type of question. They looked at studies that examined the diagnostic accuracy of at least one symptom or sign related to the urinary tract. In the history they found that dysuria, urgency, nocturia, sexual activity and urgency with dysuria were weak predictors of UTI. Increases in vaginal discharge and suprapubic pain were weak predictors of absence of infection. The only exam findings that clearly favoured a diagnosis of UTI were nitrites or leucocytes on the dipstick.
Students feel they have to do everything and as GPs we have to learn how to cut down and trim the examination to the key elements. That can feel uncomfortable but we need to appreciate the true diagnostic value of what we do.
Medina-Bombardó, D., & Jover-Palmer, A. (2011). Does clinical examination aid in the diagnosis of urinary tract infections in women? A systematic review and meta-analysis BMC Family Practice, 12 (1) DOI: 10.1186/1471-2296-12-111