Acute cystitis

Last updated: July 2021

Cystitis is an infection of the bladder and urethra that affects mainly women and girls from 2 years of age. Escherichia coli is the causative pathogen in at least 70% of cases. Other pathogens include Proteus mirabilis, Enterococcus sp, Klebsiella sp and in young women, Staphylococcus saprophyticus.

Clinical features

– Burning pain on urination and urinary urgency and frequency; in children: crying when passing urine; involuntary loss of urine.
– No fever (or mild fever), no flank pain; no systemic signs and symptoms in children.

It is essential to rule out pyelonephritis.
The symptom 'burning pain on urination' alone is insufficient to make the diagnosis. See Abnormal vaginal discharge.


– Urine dipstick test:
Perform dipstick analysis for nitrites (which indicate the presence of enterobacteria) and leukocytes (which indicate an inflammation) in the urine.
• If dipstick analysis is positive for nitrites and/or leukocytes, a urinary infection is likely. 
• In women, if dipstick analysis is negative for both nitrites and leukocytes, a urinary infection is excluded. 

– Microscopy/culture: when a dipstick analysis is positive, it is recommended to carry out urine microscopy/culture in order to confirm the infection and identify the causative pathogen, particularly in children and pregnant women.

When urine microscopy is not feasible, an empirical antibiotherapy should be administered to patients with typical signs of cystitis and positive dipstick urinalysis (leukocytes and/or nitrites).

Note: aside of these results, in areas where urinary schistosomiasis is endemic, consider schistosomiasis in patients with macroscopic haematuria or microscopic haematuria detected by dipstick test, especially in children from 5 to 15 years, even if the patient may suffer from concomitant bacterial cystitis.

– POCUS1 in cases of recurrent cystitis, perform FAST views to evaluate for signs of urinary tract pathologies. 


Cystitis in girls ≥ 2 years

cefixime PO: 8 mg/kg once daily for 3 days
amoxicillin/clavulanic acid PO (dose expressed in amoxicillin): 12.5 mg/kg 2 times daily for 3 days

Cystitis in young, nonpregnant women 

– If dipstick analysis is positive for both nitrites and leukocytes:
fosfomycin-trometamol PO: 3 g single dose
nitrofurantoin PO: 100 mg 3 times daily for 5 days 
– If dipstick analysis is negative for nitrites but positive for leukocytes, the infection may be due to S. saprophyticus. Fosfomycin is not active against this pathogen. Use nitrofurantoin as above.
– Whatever the antibiotic used, symptoms may persist for 2 to 3 days despite adequate treatment.
– In the event of treatment failure (or recurrent cystitis i.e. > 3-4 episodes per year), ciprofloxacin PO: 500 mg 2 times daily for 3 days
– For patients with recurrent cystitis, consider bladder stones, urinary schistosomiasis, urinary tuberculosis or gonorrhoea (examine the partner).

Cystitis in pregnant or lactating women

fosfomycin-trometamol PO: 3 g single dose
nitrofurantoin PO (contraindicated in the last month of pregnancy): 100 mg 3 times daily for 7 days 
cefixime PO: 200 mg 2 times daily for 5 days

Ref Notes
1 POCUS should only be performed and interpreted by trained clinicians.