Pediatric emergency medicine trisk 384

especially those who are uncircumcised, are nonspecific bacterial infections that
can present with frequency, dysuria, and purulent discharge. The term urethral
syndrome refers to an entity that can be seen in female adolescents, characterized
by acute onset of frequency and dysuria with “insignificant” bacterial counts (less
than 10,000 colony-forming units per mL). Pyuria is generally, but not absolutely,
present. Vaginitis is a common cause of the urethral syndrome. C. trachomatis
and N. gonorrhoeae are again common culprits.
Irritative vulvovaginitis (e.g., secondary to poor hygiene or bubble baths) is a
relatively common cause of frequency, usually associated with dysuria but not
with pyuria. Candidal vulvovaginitis presents with similar symptoms, but also
with white discharge, and is more common in adolescent females. Vaginal foreign
bodies in young children also can cause frequency in addition to vaginal
discharge. Frequency may be secondary to urethral trauma such as straddle
injuries, catheterization, masturbation, or sexual abuse. As an isolated symptom,
frequency would be an atypical presentation of pediatric sexual abuse. However,
urinary frequency may be seen in association with pertinent history or physical
findings (e.g., vulvovaginal infection or genital trauma), which would be
suggestive of sexual abuse. Pinworms (Enterobius vermicularis ) may
occasionally cause frequency in young females. Children with pinworm
infestation may or may not present with perineal itching. Pyuria and dysuria are
usually absent.

Extraurinary System
Neurologic
Central DI is a deficiency in the hypothalamic production of antidiuretic hormone
that leads to inability of the renal system to properly concentrate urine. Etiologies
such as septo-optic dysplasia and other developmental anomalies present in the
neonatal and infancy period. However, most causes of central DI are acquired
(e.g., head injury, brain tumors) and therefore can present at any age. DI is a lifethreatening cause of urinary frequency as lack of access to appropriate hydration
leads to hypernatremic dehydration.
A neurogenic bladder associated with a spinal cord lesion (e.g., tethered cord)

may present with urinary frequency, as the patient cannot empty the bladder fully.
Urine volumes are small but frequent. Physical examination may yield associated
abnormalities (hairy patches, cutaneous dimples or tracts, lipoma, or bony
irregularities), decreased anal tone, lower-extremity weakness, or reflex
abnormalities. Generally, postvoid residual urine volumes are increased.


Uninhibited bladder contractions (“unstable bladder” syndrome) occur
involuntarily in children who have failed to gain complete voluntary control over
the voiding reflex, related to delayed nervous system maturation. If the urethral
sphincter is relatively weak, urinary frequency associated with urgency and
enuresis may result. Females may exhibit the so-called “curtsy” sign as the child
squats and attempts to prevent leakage by compressing the perineum with the heel
of one foot. If performed, a screening ultrasound examination would reveal
normal (minimal) residual urine volumes. With maturity, spontaneous resolution
of uninhibited contractions occurs in most cases. In children with significant
developmental delay or behavioral disorders, the infantile pattern of spontaneous
bladder contraction may persist.
Abdominal
Masses in the pelvis (including abdominal tumors, appendicitis, and ovarian
torsion) that press on the bladder can cause frequency. Generally, these diagnoses
cause abdominal pain and/or other symptoms, and physical examination will
elicit tenderness. Constipation is a common cause of urinary frequency in schoolaged children. It results in large fecal masses that cause mass effect with extrinsic
bladder pressure, as well as stimulating bladder contraction or inhibiting the full
bladder capacity. Such frequency may then be small volume excretions. There is
noted association with constipation and UTI. Pregnancy should always be
considered as a cause of frequent urination in the adolescent female.
Metabolic and Endocrinopathies
Diabetes mellitus (DM) causing osmotic diuresis from increased glucosuria is an
emergent condition causing frequency. Typically, new-onset diabetes presents

with polydipsia, polyphagia, and polyuria; uncontrolled DM with or without
diabetic ketoacidosis can present similarly. Be alert for other concerning findings
including altered mental status and respiratory changes. Hypercalciuria has been
reported as a significant noninfectious cause of the “frequency–dysuria
syndrome” in pediatric patients. Onset of symptoms generally ranges from 2 to 14
years of age. Occasionally, hypercalciuria can present in early infancy, where
irritability is a hallmark symptom. Symptoms often spontaneously resolve within
2 months. There may be a positive family history of calcium urolithiasis. Dysuria
may or may not be present. Hematuria (generally microscopic) and/or crystalluria
are often seen. However, the urinalysis may be normal. If the diagnosis is
suspected and symptoms persist, studies of urinary calcium excretion and
urologic consultation should be considered. The salt-losing form of congenital


adrenal hyperplasia is a rare but life-threatening cause of frequency. Excessive
urinary excretion of sodium leads to marked dehydration with hyponatremia.
Female infants may exhibit virilization of the external genitalia. Male infants may
demonstrate increased pigmentation of the external genitalia and/or a relatively
enlarged phallus.
Drugs and Toxins
Drugs are a relatively common cause of frequency in adolescence.
Methylxanthines (caffeine, theophylline) and ethanol inhibit the production of
antidiuretic hormone. In addition to caffeinated drinks (soft drinks, coffee, black
teas, energy drinks), chocolate is another source of caffeine. Diuretic agents, such
as furosemide or hydrochlorothiazide, can cause frequency when ingested other
intentionally or accidentally. Lithium and vitamin D are also associated with
urinary frequency, interfering with renal responsiveness to antidiuretic hormone.
Many other medications may cause frequency, and a pharmacologic history
should be obtained in the child who presents with urinary frequency.
Psychogenic

Frequency may be a presenting symptom of water intoxication leading to
polyuria. Patients do not have nocturia, as enuresis is related to excessive fluid
intake. The serum sodium and osmolality may be decreased. Psychogenic
polydipsia is an extremely unusual diagnosis in young children but may present in
adolescence. Water intoxication secondary to Munchausen syndrome by proxy, an
unusual presentation of abuse in the younger child, is also a consideration. The
“extraordinary urinary frequency syndrome” can cause urinary frequency in
pediatric patients. Average age of onset is 6 years (with a range of about 2 to 11
years). Daytime frequency occurs as often as every 5 minutes. Nocturia is present
in about half the cases but usually occurs only about one to two times per night.
Generally, only reassurance is needed, as this often resolves spontaneously within
about 2 months (although in some children, the duration of symptoms can be
markedly longer). The etiology is unclear, but often has a psychogenic
component, with an apparent “trigger” (school problems, parental death, sibling
illness, etc.) identifiable in about half the cases. After consultation, a trial of
extended-release oxybutynin, behavior modification, and/or biofeedback
techniques are therapeutic considerations.

EVALUATION AND DECISION
The primary role of the emergency physician in evaluating the child with urinary
frequency is to exclude significant underlying pathology that may result in


morbidity, identify treatable conditions, and determine appropriate referral when
needed. The nature and quality of the urine should be assessed, including color
(suggesting dilute or concentrated urine), presence of blood (suggesting
nephrolithiasis or intrinsic renal disease), and foul odor (suggestive of an
infectious etiology). Additional history should then focus on elucidating the organ
system principally involved in the etiology of the urinary frequency (see Table
78.1 ). Infectious causes are heralded by dysuria, fever, or flank pain, or may be

suggested with a history of prior UTIs. Abdominal pain can signal a primary
abdominal etiology (such as severe right lower quadrant pain suggesting
appendicitis or severe colicky left lower quadrant pain suggesting ovarian
torsion). Questions related to DM should be included in the history (such as
polydipsia, polyphagia, weight loss, and family history). The presence or absence
of nocturia and enuresis is also an important historical point. Neurologic
complaints can suggest central DI. A thorough stooling history should be
obtained to evaluate for constipation, especially in toddler and school-aged
children. A complete medication and substance use history should be obtained
given the varied toxicologic etiologies of urinary frequency. The last menstrual
period of an adolescent female should be ascertained.
Perform a complete physical examination, including an accurate blood pressure
measurement. The child’s growth parameters should be plotted, and the blood
pressure should be compared with age-specific normal values to screen for
hypertension (see Chapter 37 Hypertension ). Carefully palpate the abdomen for
the presence of abdominal masses and/or tenderness, specifically in the lower
quadrants. Percussion of the flanks should be performed. Examine the
lumbosacral area closely for anomalies (hairy patches, dimples, tracts, etc.).
Special attention should be focused on the function of sacral nerves II to IV (anal
wink and sphincter tone). Unless the diagnosis is readily apparent, a rectal
examination should be performed, noting tone, tenderness, masses, and the
quality and quantity of stool in the rectal vault. The external genitalia should
always be thoroughly examined, meticulously searching for signs of infection,
trauma, or anatomic abnormalities. Signs of virilization (in the female) or
hyperpigmentation (in the male) should be evaluated. A thorough neurologic
examination with careful attention to the retinal fundi and visual fields is
warranted.
The laboratory evaluation of urinary frequency begins with a urinalysis. An
algorithm for interpretation of the urinalysis is shown in Figure 78.1 . If cystitis
or pyelonephritis is suspected by history, physical and urinalysis, a urine culture

should be sent. A catheterized specimen should be obtained for a culture in all