To develop differential diagnoses for a 38-year-old female with continuous coughing and difficulty breathing, I would ask the following questions:

• Onset and duration of symptoms: When did the cough and difficulty breathing start? Have they been continuous or intermittent?
• Severity of symptoms: How severe is the cough? Is it productive? What color is the sputum? How difficult is it to breathe?
• Associated symptoms: Does the patient have any other symptoms, such as fever, chills, chest pain, wheezing, or shortness of breath with exertion?
• Medical history: Does the patient have any underlying medical conditions, such as asthma, COPD, or heart failure? Is she taking any medications?
• Allergies: Is the patient allergic to anything?
• Social history: Does the patient smoke? Does she work in a dusty or smoky environment? Has she traveled recently?
• Exposure history: Has the patient been exposed to anyone who is sick?

Based on the patient’s history and presentation, the following differential diagnoses should be considered:

• Pneumonia: Pneumonia is an infection of the lung tissue. It can be caused by bacteria, viruses, or fungi. Common symptoms of pneumonia include cough, fever, chest pain, and shortness of breath.
• Bronchitis: Bronchitis is an inflammation of the bronchi, the tubes that carry air to and from the lungs. It can be caused by viruses, bacteria, or irritants such as smoke or dust. Common symptoms of bronchitis include cough, wheezing, and shortness of breath.
• Asthma: Asthma is a chronic lung condition that causes the airways to narrow and swell, making it difficult to breathe. Common symptoms of asthma include wheezing, coughing, and shortness of breath.
• COPD: COPD is a chronic lung condition that includes emphysema and chronic bronchitis. It can cause shortness of breath, wheezing, and coughing.
• Heart failure: Heart failure is a condition in which the heart does not pump blood as well as it should. This can cause shortness of breath, especially with exertion.
• Pulmonary embolism: A pulmonary embolism is a blood clot that travels to the lungs and blocks a blood vessel. This can cause sudden shortness of breath, chest pain, and coughing.
• Anaphylaxis: Anaphylaxis is a severe allergic reaction that can cause difficulty breathing, swelling of the throat, and a drop in blood pressure.
• Foreign body aspiration: Foreign body aspiration is the inhalation of a foreign object into the lungs. This can cause coughing, difficulty breathing, and wheezing.
• Tumor or mass: A tumor or mass in the lungs can cause coughing, difficulty breathing, and chest pain.

Pulmonary function tests (PFTs) are a group of tests that measure how well the lungs are working. Some of the most common PFTs include:

• Spirometry: Spirometry measures how much air the patient can exhale and how quickly they can exhale it.
• Lung volumes: Lung volumes measure the amount of air that the patient can hold in their lungs.
• Diffusion capacity: Diffusion capacity measures how well oxygen and carbon dioxide can move between the lungs and the bloodstream.

Which PFTs are contraindicated today?

PFTs are contraindicated in patients with the following conditions:

• Active asthma attack
• Recent respiratory infection
• Hemoptysis (coughing up blood)
• Pneumothorax (collapsed lung)
• Myocardial infarction (heart attack)
• Unstable angina
• Decompensated heart failure
• Severe pulmonary embolism

In the case of a 38-year-old female with continuous coughing and difficulty breathing, I would consider the following PFTs:

• Spirometry: To assess the patient’s airflow obstruction.
• Lung volumes: To assess the patient’s restrictive lung disease.
• Diffusion capacity: To assess the patient’s gas exchange.

I would avoid performing PFTs if the patient has a recent respiratory infection, hemoptysis, or pneumothorax. I would also avoid performing PFTs if the patient has an active asthma attack, myocardial infarction, unstable angina, decompensated heart failure, or severe pulmonary embolism.

Conclusion

The differential diagnosis for a 38-year-old female with continuous coughing and difficulty breathing is broad. It is important to take a thorough history and physical examination to narrow down the possibilities. PFTs can be helpful in assessing lung function and making a diagnosis. However, PFTs may be contraindicated in some patients.