Pediatric Pyelonephritis Clinical Presentation

Updated: Apr 25, 2022
  • Author: Patrick B Hinfey, MD; Chief Editor: Russell W Steele, MD  more...
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Signs and symptoms of urinary tract infection (UTI) and pyelonephritis vary with the age of the patient. Neonates often present with nonspecific symptoms of jaundice, hypothermia or fever, poor feeding, vomiting, and failure to thrive. Neonates, especially male newborns, may develop hyponatremia and hyperkalemia as a result of secondary pseudohypoaldosteronism.

Infants and young children aged 2 months to 2 years often present with nonspecific symptoms of fever lasting longer than 48 hours, as well as with poor feeding, vomiting, and diarrhea. Their urine may be malodorous [9] ; hematuria may be noted.

Preschoolers and school-age children present with fever for greater than 48 hours. They may complain of abdominal pain or flank pain. Vomiting, diarrhea, and anorexia may be present. Their urine is typically malodorous, and hematuria may be noted. Voiding-related symptoms including enuresis, dysuria, urgency, and frequency, may occur but need not be present.

Adolescents are most likely to present with the classic adult symptoms of fever, often with chills, rigors, and flank pain. They may have abdominal and suprapubic pain, along with voiding-related symptoms of frequency, dysuria, and hesitancy. Their urine is most often malodorous, and hematuria is variably present.


Physical Examination

Because many symptoms of pyelonephritis are nonspecific, complete physical examination is necessary to exclude other causes of the patient's symptoms. Specific findings are as follows.

General appearance

Most infants and children are uncomfortable and appear ill. Older children and adolescents may be mildly to moderately ill.

Vital signs

Fever may be present, with body temperature of more than 38°C, and often more than 39°C. Tachycardia may be present, secondary to fever and pain. Blood pressure is usually normal. Hypertension should raise concern for clinically significant obstruction or renal parenchymal disease. Hypotension may occur if sepsis and shock are present.

Abdominal findings

Abdominal pain may be present. A mass may indicate obstruction, hydronephrosis, or another anatomic abnormality. Suprapubic pain may be present. A palpable bladder indicates obstruction or functional difficulty in starting or completing voiding.

Adolescent girls may have right upper quadrant pain similar to that observed in patients with cholecystitis.

Back findings

Tenderness in the costovertebral angle (CVA), back, or flank is likely to be present in older children and adolescents. Sacral dimple or birthmarks overlying the spine may be associated with an underlying anomaly of the spinal cord. Vertebral abnormalities may be evident.

Genitourinary findings

Assess for irritation, pinworms, vaginitis, trauma, or signs of sexual abuse. A bulging hymen suggests an imperforate hymen and urethral obstruction.

Neurologic findings

Weak lower extremities or diminished reflexes may be signs of spinal-cord dysfunction, and they may be associated with a neurogenic bladder.