Pulmonology · Pediatric Respiratory Infections
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Respiratory syncytial virus (RSV) is the most common viral etiology of acute bronchiolitis in infants.
Acute bronchiolitis typically presents in infants younger than 2 years old following a viral prodrome of rhinorrhea and congestion.
Physical examination reveals diffuse expiratory wheezing, crackles, and signs of respiratory distress such as nasal flaring and intercostal retractions.
Diagnosis of acute bronchiolitis is clinical and does not require routine chest radiography or viral testing.
Supportive care consisting of nasal suctioning and adequate hydration is the primary management strategy.
Palivizumab is a monoclonal antibody indicated for prophylaxis only in high-risk infants, such as those with prematurity or chronic lung disease.
Indications for hospital admission include hypoxia (SpO2 <90-92%), apnea, or inability to maintain adequate oral intake.
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A 6-month-old male is brought to the urgent care clinic by his mother due to 3 days of nasal congestion and a low-grade fever. Over the last 24 hours, the infant has developed a persistent cough and increased work of breathing. On physical examination, the infant is tachypneic with nasal flaring and intercostal retractions. Lung auscultation reveals diffuse expiratory wheezing and scattered fine crackles bilaterally. Oxygen saturation is 93% on room air.
What is the most appropriate management for this patient?
Supportive care with nasal suctioning and hydration
The patient presents with classic signs of acute bronchiolitis, which is a clinical diagnosis managed primarily with supportive care as per current guidelines.
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Etiology / Epidemiology
Primarily affects infants <2 years, peaking at 2-6 months. Respiratory Syncytial Virus (RSV) is the most common cause.
Clinical Manifestations
Starts as URI, progresses to respiratory distress. Wheezing and crackles are classic findings.
Diagnosis
Clinical diagnosis. Pulse oximetry is the most important objective measure.
Treatment
Supportive care is the mainstay. Nasal suctioning and hydration are first-line.
Prognosis
Most recover in 7-10 days. Apnea is a critical complication in premature infants.
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Epidemiology & Etiology
Occurs most frequently in winter and spring. RSV accounts for 75% of cases, followed by rhinovirus and parainfluenza. Risk factors include prematurity, low birth weight, and lack of breastfeeding.
Pertinent Anatomy
Inflammation occurs in the bronchioles, the smallest airways. Because these airways are narrow in infants, even minor edema causes significant airway obstruction.
Pathophysiology
Viral infection leads to epithelial necrosis and increased mucus production. This results in air trapping and atelectasis, manifesting as the characteristic expiratory wheeze.
Clinical Manifestations
Initial symptoms include rhinorrhea and low-grade fever. Progression to tachypnea, nasal flaring, and intercostal retractions is common. Cyanosis or apnea are red flags requiring immediate intervention.
Diagnosis
Diagnosis is strictly clinical. Pulse oximetry is the gold standard for monitoring severity; admission is typically required if O2 saturation is <90-92%. Routine chest X-ray is not recommended unless the diagnosis is uncertain.
Treatment
Management is purely supportive. Nasal suctioning and IV/NG fluids are the only proven interventions. Bronchodilators and corticosteroids are not recommended for routine use. Palivizumab is reserved for high-risk prophylaxis.
Prognosis
Most infants recover fully within two weeks. Dehydration and respiratory failure are the primary complications requiring hospitalization. Monitor closely for apnea in infants <3 months old.
Differential Diagnosis
Asthma: recurrent episodes with family history
Pneumonia: focal findings on lung exam
Foreign body aspiration: sudden onset, unilateral wheezing
Pertussis: paroxysmal cough with inspiratory whoop
Congestive heart failure: hepatomegaly and S3 gallop