Bright red blood in the urine causes instant alarm in a patient, and usually generates an emergency appointment or an out-of hours call. Blood may also be picked up by dipstick testing or MSU during the assessment of some other problem or in a routine medical. This is often less frightening even when disclosed to the patient, but should prompt full investigation.
Dysuria is a very common symptom which is likely to be welcomed by the busy duty doctor, given that the diagnosis and management are usually straightforward. It’s worth bearing in mind, though, that there are occasional causes other than ‘cystitis’, especially in recurrent or unresolving cases. Also, genuine repeated infections can sometimes be a sign of some underlying problem.
Polyuria is a highly subjective symptom and one which presents rather less often than urinary frequency (which is dealt with separately, see 'Frequency'). Most of the causes of polyuria listed here are also, by implication, causes of polydipsia – the only causes of true polydipsia not included are those due to dehydration.
This means an increased frequency of micturition, and is usually associated with the passage of small amounts of urine. It is not the same as increased production of urine (see ‘Excessive urination’). It is a commonly presented problem, affecting women far more often than men: The average GP will deal with around 60 cases of cystitis (the main cause) each year.
Incontinence is involuntary micturition. It is not a common presenting symptom, embarrassment tending to inhibit patients, but it is often mentioned as a ‘while I’m here’ or noted by the doctor, typically because of the characteristic odour when visiting an elderly patient. It may present more frequently in the future as the problem receives more publicity and patients realise that help is available. The population prevalence in women is around 10%, but is probably much higher in older age groups.
Nocturia may present in isolation or it may be a manifestation of other urinary disturbances such as polyuria or frequency. Surprisingly, in older age groups, it is as common in women as men. Occasional nocturia is, of course, quite normal – the symptom should only be viewed as pathological when it causes disruption or distress.
Retention is failure to empty the bladder completely. The acute form characteristically affects men, presents urgently and requires immediate catheterisation or hospitalisation. Chronic retention may produce few symptoms and may only be discovered during palpation of the abdomen.