Is positive dipstick alone enough to identify the cause as infective in patients with dysuria and haematuria?

Report By: Philippa McCaffrey - 4th Year Medical Student
Search checked by Philippa McCaffrey - 4th Year Medical Student
Institution: Manchester Royal Infirmary
Date Submitted: 6th July 2005
Last Modified: 15th July 2005
Status: Blue (submitted but not checked)

Three Part Question

In [adults with dysuria and haematuria] is [positive dipstick without urine microscopy as good as positive dipstick with urine microscopy] at [identifying the cause as infective]?

Clinical Scenario

A 33 year old lady who has had cystitis before presents to the Emergency Department with pain on passing urine. Urine dipstick reveals haematuria. You wonder if it is necessary to send a sample for microscopy or whether you can assume the cause is infective and treat blind with empirical antibiotics.

Search Strategy

Medline using the OVID interface - 1966 to June Week 1 2005
Embase - 1980 to 2005 Week 24
CINAHL - 1982 to June Week 1 2005
Cochrane Library - Issue 2 2005
(exp. HEMATURIA OR haematuria.mp) AND (exp. Urination Disorders/ or DYSURIA.mp. or exp. Urinary Tract Infections/) AND (MSU.mp. OR MIDSTREAM URINE.mp. OR exp. URINALYSIS/ OR exp Microscopy/ or URINE MICROSCOPY.mp. OR exp Reagent Strips/ or URINE DIPSTICK.mp.)
Limit to (Humans, English Language, Adults (19 and over))

Search Outcome

Medline - 67 papers found of which 2 were relevant
Embase - no additional relevant papers
CINAHL - no additional relevant papers
Cochrane Library - no additional relevant papers

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Lammers RL et al 2001 USA	Adult women presenting to 1 of 2 community hospital EDs or an intermediate care centre with symptoms suggestive of a UTI (343 patients in total). Average age 33 (range 18-84). Positive urine culture was taken as Gold Standard.	Prospective observational cohort study	Dipstick	Sensitivity 96%	Women only. Not all patients presenting during the study period were included causing possible sampling error. No continuity in distick technique.
				Specificity 27%
				NPV 87%
				PPV 53%
			Microscopy	Sensitivity 95%
				Specificity 36%
				NPV 87%
				PPv 56%
Jou WW, Powers RD 1998 USA	Random sample of adult ED patients who had microscopic urinaysis ordered for detection of possible UTI or haematuria or both, following a positive dipstick. 166 patients in total, collected in 25 consecutive 8 hour sessions. Average age 45 years (range 18-97). 112 women, 54 men. Microscopy was used to confirm or ngate diagnosis.	Randomised prospective cohort study	Total number of patients where results of microscopy altered management plan made on basis of dipstick result	9/166 (5.4%)	Study not blinded. Care providers were aware that their behavoiur was being observed - this may have altered their clinical decision-making. Small sample size of patients investigated for haematuria.

Comment(s)

Both tests can be seen to have definite limitations in their diagnostic accuracy. The conclusion drawn seems to be dependent on the particular clinical situation.

Clinical Bottom Line

In adult patients presenting to the Emergency Department with haematuria and symptoms suggestive of a UTI a positive dipstick result is adequate to assist a clinical treatment decision.

References

Lammers RL, Gibson S, Kovacs D, Sears W, Strachan G Comparison of Test Characteristics of Urine Dipstick and Urinalysis at Various Test Cutoff Points Annals of Emergency Medicine 38(5):505-12, 2001 Nov
Jou WW, Powers RD Utility of dipstick urinalysis as a guide to management of adults with suspected infection or hematuria Southern Medical Journal 91(3):266-9, 1998 Mar