Differential Diagnosis for a 15-Year-Old Male in a Respiratory Clinic

Single Most Likely Diagnosis

• Asthma: This is a common condition in adolescents, often presenting with symptoms such as wheezing, cough, shortness of breath, and chest tightness. The age and the setting of a respiratory clinic make asthma a highly probable diagnosis.

Other Likely Diagnoses

• Acute Bronchitis: Typically caused by a viral infection, it can present with cough and sometimes wheezing, making it a plausible diagnosis in this age group.
• Pneumonia: Both viral and bacterial pneumonia can occur in adolescents, presenting with symptoms like cough, fever, and difficulty breathing.
• Allergic Rhinitis: Often coexists with asthma, presenting with nasal congestion, sneezing, and itchy eyes, which can indirectly affect respiratory comfort and function.
• Influenza or Other Viral Respiratory Infections: Common in adolescents, these can cause a range of respiratory symptoms.

Do Not Miss Diagnoses

• Pneumothorax: Although less common, a pneumothorax can present with sudden onset of chest pain and shortness of breath, and is critical to diagnose promptly.
• Cystic Fibrosis: If not previously diagnosed, it could present with recurrent respiratory infections and chronic cough.
• Tuberculosis (TB): Especially if the patient has been exposed to someone with TB or has recently traveled to an area with high TB prevalence.
• Foreign Body Aspiration: Can occur at any age, but is more common in younger children; however, it's crucial not to miss this diagnosis as it can be life-threatening.

Rare Diagnoses

• Interstitial Lung Disease: A broad category of diseases that affect the interstitial spaces of the lung, which can present with progressive shortness of breath.
• Sarcoidosis: A condition that can affect multiple parts of the body, including the lungs, and presents with a variety of symptoms including cough and shortness of breath.
• Lymphoma or Other Malignancies: Although rare, can present with respiratory symptoms among other systemic symptoms.

Antibiotic Use for Infectious Causes

For bacterial infections such as pneumonia, the choice of antibiotic will depend on the suspected or confirmed causative organism, local resistance patterns, and patient factors such as allergy history. Commonly used antibiotics in adolescents might include:

• Amoxicillin
• Azithromycin
• Doxycycline (for certain indications and with caution due to potential side effects)

Symbicort Dosing for Asthma

Symbicort (budesonide/formoterol) is used for the maintenance treatment of asthma. The dosing can vary based on the severity of asthma and the patient's response to treatment. Typical doses for adolescents might include:

• 2 inhalations of 100/5 mcg twice daily for mild asthma
• 2 inhalations of 200/5 mcg twice daily for moderate to severe asthma

It's essential to follow guidelines and adjust doses based on clinical response and according to the specific product labeling and local treatment guidelines.