Cystitis and Pyelonephritis
Urinary tract infections include cystitis and pyelonephritis. Cystitis is usually associated with lower urinary tract symptoms like dysuria and suprapubic pain; however, pyelonephritis will have more fever, chills, sweating, nausea, vomiting and flank pain. Fever usually resolves within 48 hours and completely after 72 hours. If symptoms persist in spite of antibiotics, then look for renal/perinephric abscess.
Urine analysis is usually sufficient for diagnosis of UTI, though the practice today is to do a urine culture if infection present to makes sure the antibiotics ordered are appropriate. Imaging is warranted when perinephric abscess is suspected. Simple uncomplicated pyelonephritis doesn't warrant imaging. Make sure to do pregnancy test on females in the child-bearing age before ordering CT scan. Indications of imaging includes persistent or recurrent symptoms after treatment and/or in patients with diabetes, immune compromise, a history of urolithiasis, anatomic abnormality, a urine pH 7.0 or higher, or a GFR 40 mL/min or lower in a patient with no history of significant renal dysfunction.
For notice, treat bacteriuria in pregnant ladies as mentioned in the link below. Treatment of asymptomatic bacteriuria in non-pregnant diabetics and elderly is not required.
Complicated UTI includes male patients, diabetics, pregnancy, catheter-associated, kidney/ureter stones, immunosuppression (medications, transplant, HIV...), neurogenic bladder, urinary obstruction, AKI/nephropathy any stage, failure of initial treatment, fistula and other anomalies, bacteremia/sepsis, Multidrug resistant or unusual organism, and post urologic procedures. Some references added pyelonephritis, however, simple episode can be still considered as uncomplicated UTI.
For board review of Bacteriuria and UTIs in pregnancy please refer to this post Bacteriuria in Pregnancy. The information otherwise in this post does not apply in pregnancy. Commonly, clinicians uses the following for treatment of uncomplicated UTI:
1- Bactrim BID for 3 days
2- Nitrofurantoin for 5 days
3- Fluoroquinolone for 3 days or 10 days if risk for complicated UTI present
4- Fosfomycin 3g single dose
For complicated UTI treatment duration and route depends on the severity and associated factors. The regimens usually extend from 7 to 14 days. Examples include:
1- Bactrim BID PO for 14 days
2- Fluoroquinolone PO for 7 days or IV for more complicated UTI (don't use if MDR is suspected, instead use broad spectrum)
3- Hospital admission and broad-spectrum IV antibiotics may be indicated according to the case especially with bacteremia or sepsis.
An interesting book to read on UTIs is this Graphic Guide.
This post covers the points you need to know for your board exams as well as for teaching residents on the daily rounds. Medical professionals can't use the information here to treat their patients nor people can use the information her to treat themselves. If you are having any medical issues, contact your local emergency services or your primary care provider. Please refer to your doctor for medical advice.