1000-2000 5 ьшò

2–6% of those require intubation.

Decreasing incidence in the United States and Canada

ETIOLOGYAND PATHOPHYSIOLOGY

Subglottic region/larynx is entirely encircled by the cricoid cartilage.

Inflammatory edema and subglottic mucus production decrease airway radius.

Small children have small airways with more compliant walls.

Negative-pressure inspiration pulls airway walls closer together.

The anatomically small airway is more susceptible to compromise and narrowing caused by the combined edema, mucus secretions, and increased compliance. Small decrease in airway radius causes significant increase in

resistance (Poiseuille law: resistance proportional to 1/radius4).

Typically caused by viruses that initially infect oropharyngeal mucosa and then migrate inferiorly

Parainfluenza virus

–Most common pathogen: 75% of cases

–Type 1 is the most common, causing 18% of all cases of croup.

–Types 2, 3, and 4 are also common.

–Type 3 may cause a particularly severe illness.

Other viruses: RSV, paramyxovirus, influenza virus type Aor B, adenovirus, rhinovirus, enteroviruses (coxsackie and echo), reovirus, measles virus where vaccination not common, and metapneumovirus

Haemophilus influenzae type B now rare with routine immunization

May have bacterial cause: Mycoplasma pneumoniae has been reported.

RISK FACTORS

Age group 2 to 3 years, with range of 6 months to 6 years

Seasonality: fall and winter

Epidemic outbreaks with associated URI symptoms

GENERALPREVENTION

Seasonal influenza shots may decrease risk.

COMMONLYASSOCIATED CONDITIONS

If recurrent (>2 episodes in a year) or during first 90 days of life, consider host factors.

Underlying anatomic abnormality (e.g., subglottic stenosis)

– In one study, found to be present in 59% children with recurrent croup

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Paradoxical vocal cord dysfunction

Gastroesophageal reflux disease

Neonatal intubation

DIAGNOSIS

Croup is a clinical diagnosis; lab tests and imaging serve only ancillary purposes. Most children who present with acute onset of barky cough, inspiratory stridor, hoarseness, and chest wall indrawing have croup.

Classic “seal-like” barking, spasmodic cough

May have biphasic stridor

Low to moderate grade fever

Upper respiratory infection prodrome lasting 1 to 7 days

Severity usually is determined by clinical observation for signs of respiratory effort: nasal flaring, retractions, tripoding, sniffing position, abdominal breathing, and tachypnea; later symptoms: hypoxia/cyanosis or fatigue

Westley croup severity score is most useful for research purposes. Westley croup score looks at five clinical features: level of consciousness, cyanosis, stridor, air entry, and retractions (≤2 mild; 3 to 7 moderate; ≥8 severe).

–Level of consciousness: normal, including sleep = 0; disoriented = 5

–Cyanosis: none = 0; with agitation = 4; at rest = 5

–Stridor: none = 0; with agitation = 1; at rest = 2

–Air entry: normal = 0; decreased = 1; markedly decreased = 2

–Retractions: none = 0; mild = 1; moderate = 2; severe = 2

No change in stridor with positioning

Nontender larynx

Inflamed subglottic region with normal-appearing supraglottic region

Differentiate from epiglottitis: non–toxic-appearing, normal voice, no drooling, is coughing (1).

HISTORY

LT, LTB, and laryngotracheobronchopneumonitis (LTBP) (triad) present with respiratory distress, stridor (often with hoarseness), barky cough, rhinorrhea, and low-grade fevers. After a 2- to 3-day prodrome, often the exacerbations occur at night that suggest hydration may be a factor.

Lack of prodrome indicates spasmodic croup.

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PHYSICALEXAM

Pulse oximetry often is normal because there is no disturbance of alveolar gas exchange.

Overall appearance: Is the child comfortable or struggling?

Work of breathing: labored or comfortable?

Sound of breathing and voice: hoarse, stridor, inspiratory wheezing, short sentences?

Observed/subjective tidal volume: sufficient for child’s size?

–Assessment of the severity of croup

Mild (0 to 2 Westley): occasional barking cough; no audible stridor at rest, and either mild or no suprasternal or intercostal retractions

Moderate (3 to 5 Westley): frequent barking cough, easily audible stridor at rest, and suprasternal and sternal retractions at rest, but little or no agitation

Severe (6 to 11 Westley): frequent barking cough, prominent inspiratory and, occasionally, expiratory stridor, marked sternal retractions, and agitation and distress

Impending respiratory failure (12 to 17 Westley): barking cough (often not prominent), audible stridor at rest (occasionally hard to hear), sternal retractions (may not be marked), lethargy or decreased level of consciousness, and often dusky appearance in the absence of supplemental oxygen (2)[B]

ALERT

Decreased breath sounds and respiratory effort may imply the child is progressing into respiratory failure and less able to mount an effort to move air. Even though there may be less obvious sign of distress, clinicians should not miss the clinically deteriorating patient.

DIFFERENTIALDIAGNOSIS

In order of decreasing frequency:

Upper respiratory infection including classic LTB

Foreign body aspiration: toddler to 4 years of age; often requires high index of suspicion

Bacterial tracheitis; similar to epiglottitis, acute septic onset

Retropharyngeal or peritonsillar abscess: similar septic appearance with dysphonia

Allergic reaction (acute angioneurotic edema); includes spasmodic croup with

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classic nocturnal exacerbations

Epiglottitis: associated with rapid onset, high fever, dysphonia, drooling, and prototypical posture of extended chin and leaning forward; H. influenzae being replaced by strep and staph organisms

Subglottic stenosis

Trauma

Airway anomalies (e.g., tracheo-/laryngomalacia)

Other anatomic obstructions: subglottic hemangioma, subglottic cyst

DIAGNOSTIC TESTS & INTERPRETATION

LTB, LTBP, and LT are clinical diagnosis and usually do not require extensive testing.

Posteroanterior and lateral neck films show funnel-shaped subglottic region with normal epiglottis: “steeple,” “hourglass,” or “pencil point” sign (present in 40–60% of children with LTB).

CT may be more sensitive for defining obstruction in a confusing clinical picture.

Patient should be monitored during imaging; airway obstruction may occur rapidly.

Also evaluate radiographs for:

–Retropharyngeal abscess: dimensions of the posterior pharynx (should be same APwidth as a contingent vertebral body)

–Epiglottitis: thumb sign: appearance of a thumb pointing posteriorly, respectively

Blood work may not be required. WBC counts may be mildly elevated with a predominance of lymphocytes; an elevated WBC shift to the left (bandemia) would suggest etiology other than LTB, most likely bacterial. Examples of this would be epiglottitis, bacterial tracheitis, and retropharyngeal abscess.

Microbiologic studies might be used to identify viral strains and specific bacteriologic species in severe presentations or to track epidemiology. H. influenzae and diphtheria as etiologic agents are rarely seen in industrialized countries in the pharynx as the result of immunization practices.

Rapid antigen or viral culture tests are available in many centers.

– Guide isolation precautions, not management.

Test Interpretation

Inflammatory reaction of respiratory mucosa

Loss of epithelial cells Thick mucoid secretions

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TREATMENT

GENERALMEASURES

Symptomatic treatment

Minimize lab tests, imaging, and procedures that upset the child; agitation worsens tachypnea and can be more detrimental than accepting a clinical diagnosis.

ECG monitoring and pulse oximetry

Pulse oximetry not as sensitive as frequent clinical checks in identifying worsening disease

MEDICATION

First Line

Well established in the literature; cornerstones of treatment are immediate nebulized epinephrine and oral dexamethasone.

Racemic or L-epinephrine (equal efficacy and side effect profiles; L- epinephrine is used for most other hospital purposes and is less expensive) (2) [A]

–Reserved for more severe cases with stridor at rest

–Racemic epinephrine: 0.05 mL/kg/dose (max 0.5 mL) of 2.25% solution nebulized in normal saline to total volume of 3 mL

–L-epinephrine: 0.5 mL/kg/dose (max 5 mL) of a 1:1,000 dilution nebulized

–Onset in 1 to 5 minutes, duration of 2 hours

–Repeat as necessary if side effects are tolerated.

–Observe child for 2 hours to ensure no recurrence after epinephrine wears

off. Corticosteroids

–Dexamethasone (least expensive, easiest), 0.15 to 0.60 mg/kg; higher doses have been traditional care, but studies have shown 0.15 mg/kg has equal efficacy (3)[B]. Single dose; IV/IM/PO has proven equal efficacy.

–Randomized controlled trials show this begins to improve symptoms within 30 minutes (4)[A]; full effect by 4 hours

–Other steroids (betamethasone, budesonide (5)[A], prednisolone) are beneficial; there may be minimal superiority of dexamethasone; also,

dexamethasone carries benefit of single-dose administration (6,7)[A]. Antibiotics are not indicated as this is a viral illness.

Oxygen as needed

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Humidified air shows no clinical benefit.

Second Line

Oseltamivir for influenza A

SURGERY/OTHER PROCEDURES

Intubation rarely is required; tube 0.5 to 1.0 mm smaller than normal

After trial of medical management, intubation may be required for fatigue caused by work of breathing or obstruction.

ADMISSION, INPATIENT, AND NURSING CONSIDERATIONS

Outpatient care in mild cases

Admit patients who do not respond to therapy or have recurrent stridor at rest after epinephrine wears off. Also admit those who have oxygen requirement, pneumonia, or other serious conditions.

In most cases, observation in the ED after medical management is sufficient. Discharge criteria

–>2 hours since last epinephrine

–No stridor at rest, no difficulty breathing

–Child able to tolerate liquids PO

–No underlying medical condition

–Caretakers able to assess changes to clinical picture and reaccess medical care

ONGOING CARE

FOLLOW-UPRECOMMENDATIONS

Patient Monitoring

Most children with croup do not require specific follow-up; should consider PCP follow-up if patient had stridor for >1 week.

DIET

Liquid diet is most comfortable for the patient and better tolerated.

Cold liquids are often more soothing.

Frequent small feedings with increased fluids for mild cases

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PATIENTEDUCATION

Croup is usually a self-limited and mild disease, but some children will need more intense medical care in the hospital.

Generally, be calming and keep your child comfortable. Keep the child cool by dressing lightly and use antipyretics if they are febrile.

Keep the child well hydrated with ample cool liquids or popsicles.

Keep the patient quiet; crying may exacerbate symptoms.

Educate parents about when to seek emergency care if symptoms worsen.

Provide emotional support and reassurance for the patient. Absolute need for medical care:

–Respiratory distress; rapid breathing; working hard to breathe; prominent chest or neck muscles with each breath

–The child becomes restless or agitated.

–The child looks unusually pale.

–High temperature (fever) lasts longer than 1 to 2 days.

Emergency ambulance if the child is:

–Blue (cyanosis)

–Lethargic

–Struggling to breathe

–Drooling and unable to swallow

PROGNOSIS

Prognosis is generally good. The few cases that are severe respond to intensive respiratory management.

Recurrence is rare in viral-mediated disease.

If croup recurs, consider an anatomic, allergic, or obstructive etiology.

COMPLICATIONS

Rare

Subglottic stenosis in intubated patients

Bacterial tracheitis

Cardiopulmonary arrest

Pneumonia

REFERENCES

1.Abedi GR, Prill MM, Langley GE, et al. Estimates of parainfluenza virusassociated hospitalizations and cost among children aged less than 5 years in the United States, 1998–2010. J Pediatric Infect Dis Soc. 2016;5(1):7–13.

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2.Bjornson CL, Johnson DW. Croup in children. CMAJ. 2013;185(15):1317–

1323.

3.Cherry JD. Clinical practice. Croup. N Engl J Med. 2008;358(4):384–391.

4.Gardner HG, Powell KR, Roden VJ, et al. The evaluation of racemic epinephrine in the treatment of infectious croup. Pediatrics. 1973;52(1):52– 55.

5.Narayan S, Funkhouser E. Inpatient hospitalizations for croup. Hosp Pediatr. 2014;4(2):88–92.

6.Schomacker H, Schaap-Nutt A, Collins PL, et al. Pathogenesis of acute respiratory illness caused by human parainfluenza viruses. Curr Opin Virol. 2012;2(3):294–299.

7.Toward Optimized Practice Working Group for Croup. Diagnosis and Management of Croup. Edmonton, AB: Toward Optimized Practice Working Group for Croup; 2008. http://www.topalbertadoctors.org. Accessed December 14, 2016.

ADDITIONALREADING

Zoorob R, Sidani M, Murray J. Croup: an overview. Am Fam Physician. 2011;83(9):1067–1073.

CODES

ICD10

J05.0 Acute obstructive laryngitis [croup]

J20.9 Acute bronchitis, unspecified

J38.5 Laryngeal spasm

CLINICALPEARLS

LT and LTB outbreaks are most common in fall and winter time for population aged 6 months to 3 years. Symptoms often occur at night.

Recurrent episodes should be followed up with a search for anatomic or allergic etiology.

Foundation of treatment is oxygen, oral/IM steroids and nebulized epinephrine.

Consider other diagnoses in acute presentations with toxic appearance:

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epiglottitis, abscess, bacterial tracheitis.

Be aware of severity should the child become less noisy; less air movement can be sign of respiratory failure.

Croup is a clinical diagnosis, thus medical management and stabilization of the patient take priority over lab testing or radiographic images.

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CRYPTORCHIDISM

Pamela Ellsworth, MD

BASICS

DESCRIPTION

Incomplete or improper descent of one or both testicles; also called undescended testes (1)

Normally, descent is in the 7th to 8th month of gestation. The cryptorchid testis may be palpable or nonpalpable.

Types of cryptorchidism

–Abdominal: located inside the internal ring

–Canalicular: located between the internal and external rings

–Ectopic: located outside the normal path of testicular descent from abdominal cavity to scrotum; may be ectopic to perineum, femoral canal, superficial inguinal pouch (most common), suprapubic area, or opposite hemiscrotum

–Retractile: fully descended testis that moves freely between the scrotum and the groin

–Iatrogenic: Previously descended testis becomes undescended secondary to scar tissue after inguinal surgery, such as an inguinal hernia repair or hydrocelectomy.

–Also may be referred to as palpable versus nonpalpable (1)

System(s) affected: reproductive

Synonym(s): undescended testes (UDT)

EPIDEMIOLOGY

Incidence

Predominant age: premature newborns

Predominant sex: male only

Prevalence

In the United States, cryptorchidism occurs in 1–3% of full-term and 15–30% of premature newborn males (2).

Spontaneous testicular descent occurs by age 1 to 3 months in 50–70% of fullterm males with cryptorchidism.

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