Chapter 9. Dysuria

Dysuria, defined as painful urination, indicates irritation of either the bladder, urethra, or prostate gland.1 It may be associated with urinary frequency and urgency or may be used to describe the discomfort associated with these symptoms. A complaint of dysuria can be difficult to elicit in younger children who may have difficulty distinguishing between dysuria and perineal or genital irritation.2

Overall, the most common conditions associated with dysuria are urinary tract infections (UTIs), urethritis, and local irritation. However, there are many other causes to consider (Table 9–1).2–4 The patient's age and the presence of specific clinical or laboratory findings can help focus the differential diagnosis. Additionally, sexual abuse and pruritis associated with pinworm infestation can mimic dysuria.

Infection

Prepubertal Children

A complaint of dysuria can be difficult to ascertain in younger children, but the presence of fever, increased fussiness, decreased appetite, lower abdominal pain, or suprapubic or flank tenderness may signal the presence of a UTI. Among febrile infants and children of age 2 months to 2 years with no other source of fever, the prevalence of a UTI is about 5% with an overall predominance of girls. Male neonates are five to eight times more likely to have a UTI than girls during the neonatal period but after 3 months of age, female infants are two times more likely to be infected and 1–5-year-old girls are 10–20 times more likely to be compared with boys.5

A UTI can affect either the upper or lower genitourinary tract. The presence of fever and other signs such as flank pain point to pyelonephritis rather than cystitis. These signs, however, are more reliable in older children. The most common organisms associated with UTI are enterobacteria. Escherichia coli is associated with 70–90% of infections.5,6 Other organisms include Pseudomonas aeruginosa, Proteus mirabalis, and Enterococcus spp. Viruses, though less common, can also cause cystitis. Adenovirus in particular is a well-described cause of acute hemorrhagic cystitis. Uncommon organisms that cause UTI include Staphylococcus aureus, Schistosomae (associated with acute hemorrhagic cystitis), and Mycobacterium tuberculosis.1,5,6S. aureus most commonly causes infection when there is a predisposing condition such as an indwelling catheter or concurrent infection such as a renal abscess.

Other causes of dysuria in the prepubertal child include vaginitis in girls and balanitis in boys. Vaginitis can be caused by group A Streptococcus, Shigella spp., or Candida spp. Varicella lesions involving the perineum and vagina may also cause dysuria.4 If there are signs of vaginitis or urethritis and the source is found to be a sexually transmitted organism such as Chlamydia trachomatis or Neisseria gonorrhoeae, an evaluation for sexual abuse should be initiated.

Postpubertal Children

Among adolescents, UTI remains the most common cause of dysuria, particularly in girls. UTIs occur less commonly in postpubertal boys in the absence of an anatomic urinary tract abnormality. Beyond UTI, the most important consideration is sexually transmitted infection causing urethritis, cervicitis, or vaginitis. The symptoms for both urinary tract and sexually transmitted infections overlap such that evaluation for both etiologies is often required in adolescents. One prospective study of adolescent females with dysuria showed that only 17% had a UTI, while 15% had C. trachomatis and 29% had urethritis and vaginitis caused by a variety of sexually and nonsexually transmitted agents.7 UTIs are caused by many of the same pathogens that cause infection in younger children, with the exception of Staphylococcus saprophyticus,7 which occurs more commonly in adolescent girls.

The burden of sexually transmitted infection among adolescents is high. According to the Centers for Disease Control and Prevention (CDC), 40% of all cases of C. trachomatis are diagnosed in 15–19-year-old females.7 Since a history of sexual activity is not always reliable, screening for N. gonorrhoeae and C. trachomatis should be a routine part of the evaluation of an adolescent with dysuria, particularly if no other cause has been identified. Also, among boys, a complaint of dysuria is much more likely to be due to urethritis rather than UTI.8 The presence of urethral or vaginal discharge strongly suggests urethritis, most commonly caused by either N. gonorrhoeae or C. trachomatis. Dysuria can also be associated with genital herpes simplex virus infection or with vaginitis caused by other sexually or nonsexually transmitted agents such as Candida albicans, Trichomonas vaginalis, and Gardnerella vaginalis.7,9

In an adolescent with dysuria, fever, and abdominal or flank pain, an upper genitourinary tract infection such as pyelonephritis or pelvic inflammatory disease (PID) should be considered. However, these symptoms can overlap with a wide range of other intra-abdominal conditions such as appendicitis, gastroenteritis, and nephrolithiasis.7 The presence of flank pain and pyuria helps to distinguish pyelonephritis. Among sexually active adolescent females, assessing for PID is extremely important given the potential long-term sequelae of untreated infection. In addition to dysuria, patients may complain of lower abdominal or pelvic pain, fever, dyspareunia, vaginal discharge, and vaginal bleeding.9 However, symptoms for PID can be very mild and only include one or two of these findings. In these cases, PID may not be considered in the differential diagnosis and infection can be missed. Minimal criteria defined by the CDC for the diagnosis of PID include cervical motion, uterine, or adnexal tenderness with or without other signs of of lower genitourinary tract infection. These criteria, while not very specific, minimize the frequency of missed infection.

Noninfectious Causes of Dysuria

In younger children, particularly those who present with isolated dysuria, local irritation is a common etiology. Local irritation can be induced by exposure to a variety of products including bubble bath, perfumed soap, or detergents. There may be no apparent signs of irritation on physical examination but symptom resolution will coincide with removal of the offending exposure. Dysuria is also caused by local trauma associated with genital self-exploration, masturbation, or by direct trauma caused by events such as straddle injuries.2–4 It is often difficult to elicit a history of trauma. Younger children may not remember an injury event and older children may be reluctant to disclose self-exploration or masturbation.2–4

Anatomic abnormalities can also cause dysuria. In young girls, labial adhesions are relatively common. While they are usually asymptomatic, there can be associated dysuria, especially if the urethral meatus is involved. Urinary strictures have also been found to cause dysuria in both younger children and adolescents.4 Additionally, genitourinary abnormalities can predispose children to infection that results in dysuria. For infants and young children with a first UTI or older children with recurrent infection, evaluation for these abnormalities should be considered.10

Dysfunctional elimination syndrome (DES) with associated idiopathic urethritis is a relatively common cause of dysuria in younger children.11,12 This diagnosis should be strongly considered if there is (1) no evidence of infection, (2) no history of exposure to irritants or trauma, and (3) no anatomic abnormality. Here, dysuria occurs in conjunction with constipation, which causes inadequate bladder emptying and chronic uretheral irritation. Bladder and bowel retraining programs effectively treat the urethritis.11,12

If dysuria is accompanied by hematuria and flank or lower abdominal pain with no fever or other signs of infection, urolithiasis should be considered. This is relatively uncommon among children and adolescents unless there is a history of a predisposing metabolic disorder such as hypercalciuria.13

When no cause for dysuria is identified, the complaint is isolated or is associated with times of stress, psychogenic dysuria should be considered. It is also important to seek other causes of perineal irritation such as pinworm infestation, which causes discomfort that is misidentified as dysuria.2,3 If dysuria is associated with multiple symptoms such as rash, fever, conjunctivitis, the systemic causes of dysuria must be ruled out.2 However, in these cases, dysuria is not usually the presenting complaint.

The initial history should clarify the presence of dysuria versus perineal irritation and determine whether other accompanying symptoms readily suggest a specific cause (Table 9–2).3,4,14 While systemic conditions such as Stevens–Johnson syndrome are uncommon, they do require urgent medical attention. The presence of rash, conjunctivitis, or meatal erythema should prompt a more focused evaluation for Stevens–Johnson syndrome. Recurrent dysuria, particularly when associated with oral or genital ulcers suggests Behcet disease. If there is no indication that a systemic condition is present, the clinician should focus on determining the presence of infection. History should assess the following3:

1. Is there presence of fever?

2. Is there presence of abdominal or flank pain?

3. Is there any urethral discharge?

4. Is there any blood in the urine?

As discussed earlier, fever and abdominal pain suggest either pyelonephritis or PID, both of which require prompt diagnosis and treatment to prevent late complications associated with these infections. In the absence of these findings, the clinician should attempt to identify other signs of infection such as urinary urgency or frequency. For adolescents, a sexual history should be elicited to assess for the possibility of a sexually transmitted infection. While sexually transmitted infections often present with urethral discharge, they may present with isolated dysuria only.9 The absence of reported sexual activity does not preclude the possibility of a sexually transmitted infection, as adolescents do not always disclose this history.

Microscopic and gross hematuria may result from a UTI. Some pathogens are more likely to be associated with hematuria. S. saprophyticus often causes microscipic hematuria and Schistosomiasis and adenovirus often cause gross hematuria.5,7 While sexually transmitted infections can be associated with abnormal vaginal bleeding, they are usually not associated with hematuria. Therefore, in the context of hematuria, UTI is more likely to be the cause of dysuria rather than sexually transmitted infection unless there is concurrent infection.7

If the initial history does not point to infection, the history should then focus upon the common noninfectious causes of dysuria. Exposure to any local irritants or injury should be elicited. Masturbation should also be considered; however, this history may be difficult to elicit from both younger children and adolescents. Flank or abdominal pain and hematuria without fever suggest urolithiasis. Isolated hematuria also suggests either hypercalciuria or nephrolithiasis. A family history of metabolic disorders increases the likelihood of urinary stones. Isolated dysuria with a history of constipation suggests DES.

Evaluation of dysuria begins with a complete history and physical focusing upon the clinical findings detailed above. Unless a systemic condition is suspected as the cause of dysuria, laboratory evaluation should begin with a urinalysis. History, physicial examination, and the results of the urinalysis should direct subsequent testing (Table 9–3).2–4,8

Radiologic studies are generally not indicated for the initial evaluation of dysuria unless urolithiasis is suspected, or if there is suspicion of complicated pyelonephritis or a renal abscess. For younger children with a first UTI, imaging should be pursued to diagnose an anatomic abnormality such as posterior urethral valves and to detect the presence of vesicoureteral reflux that predisposes to infection; a voiding cysterourethrogram is the study of choice. A renal ultrasound may be performed to diagnose hydronephrosis or renal scarring. Renal scarring is more likely to occur in younger children after a UTI and identifying any predisposing abnormalities is important to prevent further infection and renal damage.5

An algorithm for the evaluation of dysuria for any age group is described in Figure 9–1.2,4 After performing the history and physical in all ages, a urinalysis is the first diagnostic test to be performed, even among sexually active adolescents in whom a sexually transmitted infection is suspected since a sexually transmitted infection and UTI can occur concurrently.7

In any patient with dysuria older than 6 years of age, while awaiting results of the evaluation, symptomatic relief can be offered with phenazopyridine (Pyridium): 4 mg/kg by mouth three times per day (maximum 12 mg/kg/day) or 100–200 mg three times per day for children older than age 12 years. Treatment should not be given for more than 2 days.15

Referral to Emergency Department

1. Infants and children with UTI and systemic signs such as high fever or inability to tolerate oral medications should be referred for admission and parenteral antibiotics.5,10

2. Any child or adolescent with a UTI who fails oral antibiotic treatment.

3. Any adolescent who fails oral antibiotic treatment for PID.

4. Any child for whom sexual abuse is suspected.

Referral to a Specialist

1. Any child found to have urethral strictures or any other anatomic abnormality should be referred to a pediatric urologist.3

2. A child with DES may benefit from a referral to outpatient urology for management if no response to a bowel/bladder retraining program.11,12

3. Presence of urinary stones may warrant referral to metabolic or endocrine specialist if the patient appears to have an underlying condition such as hypercalciuria.