Symptoms

 

 

 

Factor Risk
Gender 3 times higher risk in females
Age Variably increased risk in infants and younger children
Circumcision status 4–20 times higher risk in uncircumcised males
Race/ethnicity Half the risk in African American children compared with nonblack children
Fever Increased risk with fever > 39°C for both boys and girls, and with fever duration > 24 h in boys or > 48 h in girls
History of UTI 2-fold increased risk
Genital sexual activity Increased risk
Previous urinary tract infection Increased risk

Bacteria most commonly cause UTIs, although viruses and other infectious agents can also be urinary pathogens. The vast majority of UTIs in all age groups typically occur from retrograde contamination of the lower urinary tract with organisms from the perineum and periurethral area. In neonates, however, UTIs typically develop after seeding of the renal parenchyma from hematogenous spread.

Escherichia coli is the most common cause of UTI in children, and this is likely because of its ubiquitous presence in stool combined with bacterial virulence factors that improve adhesion to and ascent of the urethra.4Additional pathogens include KlebsiellaProteus, and Enterobacter species. Enterococcus species, Staphylococcus aureus, and group B streptococci are the most common gram-positive organisms and are more common in neonates. Staphylococcus saprophyticus can cause UTI in adolescents, and Chlamydia trachomatis may be present in adolescents with urinary tract symptoms and microhematuria. Adenovirus may cause culture-negative acute cystitis in young boys.

Mechanical defenses in humans, such as normal urinary outflow, clear most bacteria that are introduced into the bladder. Anatomic abnormalities can make bacterial proliferation or persistence in the bladder more likely. Additional factors influencing the development of UTI include virulence of the pathogen, vesicoureteral reflux, urolithiasis, poor hygiene, voluntary urinary retention, and abnormal bladder function due to constipation. There are occasionally patients, usually preschool- or school-aged females, who have recurrent UTI without a clear anatomic abnormality or identifiable risk factors. Genetic investigation may allow identification of these at-risk individuals.12 Rare causes of UTI in children include indwelling urinary catheters or UTI from embolism or secondary to infection of other body areas.

 

 

 

 

 

 The vast majority of UTIs in all age groups typically occur from retrograde contamination of the lower urinary tract with organisms from the perineum and periurethral area. 

Escherichia coli is the most common cause of UTI in children, and this is likely because of its ubiquitous presence in stool combined with bacterial virulence factors that improve adhesion to and ascent of the urethra.4 Additional pathogens include KlebsiellaProteus, and Enterobacter species. Enterococcus species, Staphylococcus aureus, and group B streptococci are the most common gram-positive organisms and are more common in neonates. Staphylococcus saprophyticus can cause UTI in adolescents, and Chlamydia trachomatis may be present in adolescents with urinary tract symptoms and microhematuria. Adenovirus may cause culture-negative acute cystitis in young boys.

Mechanical defenses in humans, such as normal urinary outflow, clear most bacteria that are introduced into the bladder. Anatomic abnormalities can make bacterial proliferation or persistence in the bladder more likely. Additional factors influencing the development of UTI include virulence of the pathogen, vesicoureteral reflux, urolithiasis, poor hygiene, voluntary urinary retention, and abnormal bladder function due to constipation. There are occasionally patients, usually preschool- or school-aged females, who have recurrent UTI without a clear anatomic abnormality or identifiable risk factors. Genetic investigation may allow identification of these at-risk individuals.12 

Rare causes of UTI in children include indwelling urinary catheters or UTI from embolism or secondary to infection of other body areas.

 

 

 

 

The highest incidence occurs during the first year of life for both genders.3 

 

 However, the risk of UTI as an occult source of infection remains substantial in fully immunized children, depending upon age, gender, and circumcision status [45]. This risk guides recommendations for evaluation and treatment in these patients [70].

●For children with FWS who are completely immunized, we suggest that girls less than 24 months of age, uncircumcised boys less than 12 months, and circumcised boys <6 months receive a urinalysis and urine culture. Urine for culture should be collected by catheterization or, in exceptional cases (eg, tight phimosis or severe labial adhesions), suprapubic aspiration. Bag specimens should not be sent for culture because they are frequently contaminated. (See "Urine collection techniques in infants and children with suspected urinary tract infection" and 'Urinary tract infection' above.)

●For girls >24 months of age, uncircumcised boys >12 months of age and circumcised boys >6 months of age, all of whom have been completely immunized, we do not suggest routine laboratory evaluation or presumptive treatment with antibiotics. However, urinalysis and urine culture should be obtained in those with signs or symptoms of UTI, which must be specifically sought (eg, dysuria, frequency, abdominal pain, back pain, new onset incontinence). In addition, children with a prior history of UTI, urogenital anomalies, or prolonged fever (>48 hours) warrant urinalysis and urine culture. (See 'Urinary tract infection' above.)

Some experts suggest that a high fever without a source (>39°C [102.2°F]) is sufficient justification for urine culture on the first visit in uncircumcised boys 24 months of age or younger (algorithm 1). (See "Urinary tract infections in infants and children older than one month: Clinical features and diagnosis", section on 'Decision to obtain'.)

●Children with FWS who are completely immunized against Hib and pneumococcus, with either PCV7 or PCV13, meet criteria for urine testing, and have an abnormal urinalysis should be treated for UTI. Appropriate follow-up should be arranged. ]

 

Complications of Injecting Drug Use

  • Local problems—Abscess (Figures 240-2 
    Image not available.

    A 32-year-old woman with type 1 diabetes developed large abscesses all over her body secondary to injection of cocaine and heroin. Her back shows the large scars remaining after the healing of these abscesses. (Courtesy of ­Richard P. Usatine, MD.)

    and 240-3; Abscess), cellulitis, septic thrombophlebitis, local induration, necrotizing fasciitis, gas gangrene, pyomyositis, mycotic aneurysm, compartmental syndromes, and foreign bodies (e.g., broken needle parts) in local areas.2
    • IDUs are at higher risk of getting methicillin-resistant Staphylococcus aureus(MRSA) skin infections that the patient may think are spider bites (Figure 240-4).
    • Some IDUs give up trying to inject into their veins and put the cocaine directly into the skin. This causes local skin necrosis that produces round atrophic scars (Figure 240-5).
  • IDUs are at risk for contracting systemic infections, including HIV and hepatitis B or hepatitis C.
    • Injecting drug users are at risk of endocarditis, osteomyelitis (Figures 240-6and 240-7), and an abscess of the epidural region. These infections can lead to long hospitalizations for intravenous antibiotics. The endocarditis that occurs in IDUs involves the right-sided heart valves (see Chapter 50, Bacterial Endocarditis).2 They are also at risk of septic emboli to the lungs, group A β-hemolytic streptococcal septicemia, septic arthritis, and candidal and other fungal infections.

 

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Content 13

Content 11

 

A

A 75-year-old triathlete complains of gradually worsening vision over the past year. It seems to be involving near and far vision. The patient has never required corrective lenses and has no significant medical history other than diet-controlled hypertension. He takes no regular medications. Physical examination is normal except for bilateral visual acuity of 20/100. There are no focal visual field defects and no redness of the eyes or eyelids. Which of the following is the most likely diagnosis?

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The correct answer is A. You answered A.

Age-related macular degeneration is a major cause of painless, gradual bilateral central visual loss. It occurs as nonexudative (dry) or exudative (wet) forms. Recent genetic data have shown an association with the alternative complement pathway gene for complement factor H. The mechanism link for that association is unknown. The nonexudative form is associated with retinal drusen that leads to retinal atrophy. Treatment with vitamin C, vitamin E, beta-carotene, and zinc may retard the visual loss. Exudative macular degeneration, which is less common, is caused by neovascular proliferation and leakage of choroidal blood vessels. Acute visual loss may occur because of bleeding. Exudative macular degeneration may be treated with intraocular injection of a vascular endothelial growth factor antagonist (bevacizumab or ranibizumab). Blepharitis is inflammation of the eyelids usually related to acne rosacea, seborrheic dermatitis, or staphylococcal infection. Diabetic retinopathy, now a leading cause of blindness in the United States, causes gradual bilateral visual loss in patients with long-standing diabetes. Retinal detachment is usually unilateral and causes visual loss and an afferent pupillary defect.

 

Mr. Jenson is a 40-year-old man with a congenital bicuspid aortic valve who you have been seeing for more than a decade. You obtain an echocardiogram every other year to follow the progression of his disease knowing that bicuspid valves often develop stenosis or regurgitation requiring replacement in middle age. Given his specific congenital abnormality, what other anatomic structure is important to follow on his biannual echocardiograms?

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The correct answer is A. You answered A.

The answer is A. (Chap. 282) Bicuspid aortic valve is among the most common of congenital heart cardiac abnormalities. Valvular function is often normal in early life and thus may escape detection. Due to abnormal flow dynamics through the bicuspid aortic valve, the valve leaflets can become rigid and fibrosed, leading to either stenosis or regurgitation. However, pathology in patients with bicuspid aortic valve is not limited to the valve alone. The ascending aorta is often dilated, misnamed “poststenotic” dilatation; this is due to histologic abnormalities of the aortic media and may result in aortic dissection. It is important to screen specifically for aortopathy because dissection is a common cause of sudden death in these patients.

 


 

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