Urinary Tract Infections in Children - Treatment

Treatment

Treatment has four main goals:

1. elimination of symptoms and eradication of bacteriuria in the acute episode

2. prevention of renal scarring

3. prevention of a recurrent UTI

4. correction of associated urological lesions.

Severe UTIs

               A severe UTI requires adequate parenteral fluid replacement and appropriate antimicrobial treatment, preferably with cephalosporins (third generation). If a Gram-positive UTI is suspected by Gram stain, it is useful to administer aminoglycosides in combination with ampicillin or amoxicillin/clavulanate. Antimicrobial treatment has to be initiated on an empirical basis, but should be adjusted according to culture results as soon as possible. In patients with an allergy to cephalosporins, aztreonam or gentamicin may be used. When aminoglycosides are necessary, serum levels should be monitored for dose adjustment. Chloramphenicol, sulfonamides, tetracyclines, rifampicin, amphotericin B and quinolones should be avoided. The use of ceftriaxone must also be avoided due to its undesired side effect of jaundice. A wide variety of antimicrobials can be used in older children, with the exception of tetracyclines (because of teeth staining). Fluorinated quinolones may produce cartilage toxicity, but if necessary may be used as second-line therapy in the treatment of serious infections, since musculoskeletal adverse events are of moderate intensity and transient. For a safety period of 24-36 hours, parenteral therapy should be administered. When the child becomes afebrile and is able to take fluids, he/she may be given an oral agent to complete the 10-14 days of treatment, which may be continued on an outpatient basis. This provides some advantages, such as less psychological impact on the child and more comfort for the whole family. It is also less expensive, well tolerated and eventually prevents opportunistic infections. The preferred oral antimicrobials are: trimethoprim (TMP), co-trimoxazole (TMP plus sulphamethoxazole), an oral cephalosporin, or amoxicillin/clavulanate. However, the indication for TMP is declining in areas with increasing resistance. In children less than 3 years of age, who have difficulty taking oral medications, parenteral treatment for 7-10 days seems advisable, with similar results to those with oral treatment. If there are significant abnormalities in the urinary tract (e.g. vesicoureteral reflux, obstruction), appropriate urological intervention should be considered. If renal scarring is detected, the patient will need careful follow-up by a paediatrician in anticipation of sequelae such as hypertension, renal function impairment and recurrent UTI.

               An overview of the treatment of febrile UTIs in children is given in Figure: Treatment of ebrile UTIs in Children and the dosing of antimicrobial agents is outlined in Table Dosing of Antimicrobial Agents in Children Aged 3 Months to 12 Years.

Figure. Treatment of Febrile UTIs in Children

Table. Dosing of Antimicrobial Agents in Children Aged 3 Months to 12 Years*

Antimicrobial agent	Application	Age	Total dosage per day	Doses per day
Ampicillin	Intravenous	3-12 months	100-300 mg/kg BW	3
Ampicillin	Intravenous	1-12 years	60-150 (-300) mg/kg BW	3
Amoxicillin	Oral	3 months to 12 years	50-100 mg/kg BW	2-3
Amoxicillin/clavulanate	Intravenous	3 months to 12 years	60-100 mg/kg BW	3
Amoxicillin/clavulanate	Oral	3 months to 12 years	37.5-75 mg/kg BW	2-3
Cephalexin Treatment	Oral	3 months to 12 years	50-100 mg/kg BW	3
Prophylaxis Cefaclor	Oral	1-12 years	10 mg/kg BW	1-2
• Treatment	Oral	3 months to 12 years	50-100 mg/kg BW	3
• Prophylaxis	Oral	1-12 years	10 mg/kg BW	1-2
Cefixime	Oral	3 months to 12 years	8-12 mg/kg BW	1-2
Cetriaxone	Intravenous	3 months to 12 years	50-100 mg/kg BW	1
Aztreonam	Intravenous	3 months to 12 years	(50)-100 mg/kg BW	3
Gentamicin	Intravenous	3-12 months	5-7.5 mg/kg BW	1-3
Gentamicin	Intravenous	1-2 years	5 mg/kg BW	1-3
Trimethoprim
• Treatment	Oral	1-12 years	6 mg/kg BW	2
• Prophylaxis	Oral	1-12 years	1-2 mg/kg BW	1
Nitrofurantoin
• Treatment	Oral	1-12 years	3-5 mg/kg BW	2
• Prophylaxis	Oral	1-12 years	1mg/kg BW	1-2

 BW = body weight.

Simple UTIs

               A simple UTI is considered to be a low-risk infection in children. Oral empirical treatment with TMP, an oral cephalosporin or amoxicillin/clavulanate is recommended, according to the local resistance pattern. The duration of treatment in uncomplicated UTIs treated orally should be 5-7 days. A single parenteral dose may be used in cases of doubtful compliance and with a normal urinary tract. If the response is poor or complications develop, the child must be admitted to hospital for parenteral treatment.

Prophylaxis

               If there is an increased risk of pyelonephritis, e.g. vesicoureteral reflux, and recurrent UTI, low-dose antibiotic prophylaxis is recommended. It may also be used after an acute episode of UTI until the diagnostic work-up is completed. The most effective antimicrobial agents are: Nitrofurantoin, TMP, cephalexin and cefaclor.