What is the diagnosis for a 16-year-old patient presenting with one week of fatigue, weakness, dyspnea (shortness of breath), cough, congestion, ageusia (loss of taste), and anorexia (loss of appetite), with negative Coronavirus (COVID) and Influenza (Flu) tests, hypotension (Blood Pressure 84/52), and bradycardia (heart rate 79), and a temperature of 98.5 degrees Fahrenheit?

Differential Diagnosis for a 16-year-old with Fatigue, Weakness, and Respiratory Symptoms

Single Most Likely Diagnosis

• Viral pneumonia or atypical pneumonia: Given the symptoms of fatigue, weakness, shortness of breath, cough, and congestion, along with a negative COVID-19 and flu test, a viral pneumonia or atypical pneumonia (such as mycoplasma pneumonia) is a plausible diagnosis. The low blood pressure (84/52) and mild hypothermia (temp 98.5) may indicate a systemic infection.

Other Likely Diagnoses

• Anemia or iron deficiency: The patient's symptoms of fatigue, weakness, and shortness of breath could be indicative of anemia or iron deficiency, especially if there is a history of heavy menstrual bleeding or poor dietary intake.
• Asthma or chronic obstructive pulmonary disease (COPD) exacerbation: Although less likely in a 16-year-old, an asthma or COPD exacerbation could present with similar respiratory symptoms.
• Pulmonary embolism: Although rare in adolescents, a pulmonary embolism could cause sudden onset of shortness of breath, cough, and fatigue.

Do Not Miss Diagnoses

• Sepsis: The patient's low blood pressure and mild hypothermia raise concerns for sepsis, a life-threatening condition that requires prompt recognition and treatment.
• Cardiac issues (e.g., myocarditis, cardiomyopathy): The patient's symptoms of fatigue, weakness, and shortness of breath could be indicative of a cardiac issue, which would be critical to diagnose and treat promptly.
• Pneumothorax or other thoracic emergencies: A pneumothorax or other thoracic emergencies, such as a pulmonary hemorrhage, could present with sudden onset of shortness of breath and cough.

Rare Diagnoses

• Cystic fibrosis: Although rare, cystic fibrosis could present with chronic respiratory symptoms, including cough and shortness of breath.
• Interstitial lung disease: This is a rare condition in adolescents, but it could present with similar respiratory symptoms.
• Tuberculosis: Although less common in the United States, tuberculosis could present with chronic cough, fatigue, and weight loss.