Pulmonary Manifestations of Systemic Disease

Question 1

In the context of pulm, what is parenchyma?

Answer 1

The interstitium

Question 2

What is the VINDICATE mnemonic?

Answer 2

Vascular

Infection

Neoplasm

Drugs

Inflammatory/idiopathic/iatrogenic

Congenital

Autoimmmune

Trauma

Endocrine/metabolic

This mnemonic helps you build your differential diagnosis.

Question 3

What is ALS?

Answer 3

Amyotrophic lateral sclerosis aka Lou Gehrig’s disease is a relentlessly progressive neurodegenerative disease that causes weakness. Progressive muscle weakness causes upper and lower motor neuron dysfunction. Patients may develop dysphagia (trouble swallowing) due to uncoordinated pharyngeal muscle movement resulting in aspiration of fluids and foods.

ALS is rare (1-3 cases/100,000). There is no racial or ethnic predilection.

It may occur in 3rd decade and incidence peaks in 7th or 8th decades

Question 4

What are pulmonary manifestations of ALS?

Answer 4

• Chronic aspiration due to uncoordinated pharyngeal muscle movement can cause recurrent pneumonia or pneumonitis from foreign substances going into lungs.
• Respiratory muscle weakness can cause inadequate ventilation (CO₂ rise), nocturnal hypoventilation, and weak cough

When thinking about ALS, think about muscle dysfunction which will cause trouble swallowing/aspiration of food, and muscle weakness of respiratory muscles.

Question 5

What is seen on CXR for ALS related pulmonary problems?

Answer 5

1. Aspirated objects typically go down the right main bronchus. The right main bronchus is pointed more downards than the left main bronchus so aspirated objects typically go down the right main bronchus and lodge in the right middle lobe (and sometimes right lower lobe) causing infiltrate.
2. Low lung volumes (from weak respiratory muscles). Ordinarily when you shoot a chest x-ray, you ask the patient to take a deep breath. ALS patients have weak respiratory muscles so they will have low lung volumes in the CXR.

Question 6

What are the PFTs like when you have neuromuscular weakness (e.g. ALS)?

Answer 6

Neuromuscular weakness presents with restrictive patterns in the PFT. This is because in order to get up to high lung volumes, you need to generate significant force/do work. Also, to be able to get a normal FEV with spirometry, you need to generate significant force too. So, if your muscles are weak, you cannot do this.

Reduced TLC (muscles can’t get it up)

Increased RV (muscles can’t push all of the volume out)

Reduced FEV₁ (muscles can’t push volume out quickly)

Reduced FVC (muscles can’t get lung volume up)

Preserved FEV₁/FVC ratio because both were reduced proportionally

Question 7

With neuromuscular problems, what is a positional strategy you can use during spirometry to better assess muscle function?

Answer 7

You have the patient do the spirometry lying down. Patients with neuromuscular problems will have a reduced FVC in supine position.

In an upright position, gravity assists the diaphragm. In the supine position, the gravity doesn’t help. In clinic, this helps us to assess if someone has a muscle related problem w/ their breathing deficiency.

Question 8

What are the respiratory strength tests and findings that indicate pulmonary issues related to neuromuscular disease?

Answer 8

Maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP).

The patient generates the most negative and most positive pressures against a closed valve. Both MIP And MEP will be reduced if there is neuromuscular dysfunction causing pulmonary issues.

Question 9

What is a respiratory rate test that you can give ot a patient to test for neuromuscular dysfunction causing pulmonary problems?

Answer 9

Maximum voluntary ventilation. The patient breathes for 12 seconds as deep and as fast as they can and you see how their minute ventilation is.

Question 10

What happens to D_LCO with neuromuscular diseases?

Answer 10

Initially, D_LCO is normal. However, as muscles weaken, the patient starts to breathe at lower lung volumes and develops atelectasis and shunts. (Won’t be taking regular deep breaths and parts of the lung collapse/close and don’t open because the patient’s muscles are too weak). D_LCO will drop in that case.

Question 11

How does arterial blood gas look for neuromuscular disease?

Answer 11

Elevated P_CO2 or hypercarbia (due to low minute ventilation)

Question 12

What is the treatment for neuromuscular weakness causing pulmonary deficiency?

Answer 12

1. Noninvasive positive pressure ventilation
2. Aspiration precautions
3. Cough assistance

Question 13

Name an acute neuromuscular disease that can cause pulmonary issues

Answer 13

Guillain-Barre (GBS)

Question 14

Name 2 relapsing neuromuscular disease that can cause pulmonary issues

Answer 14

Multiple Sclerosis (MS), myasthenia gravis (MG)

Question 15

Name a chronic, progressive neuromuscular disease that can cause pulmonary problems.

Answer 15

ALS

Question 16

True or False: Rheumatoid Arthritis can manifest in any part of the pulmonary system.

Answer 16

True

Question 17

A patient with Rheumatoid Arthritis presents with a left pleural effusion. Will they have an obstructive or restrictive pattern? What happens to D_LCO? What about D_LCO/V_A?

Answer 17

They will have a restrictive pattern and a reduced D_LCO that has an improvement in value when normalized for V_A

Question 18

In a patient with Rheumatoid Arthritis that presents with pleural effusion, how do you confirm that the RA is causing the effusion?

Answer 18

You have to sample the fluid and rule out other causes for the effusion. (you need negative cytology and culture results)

Question 19

True or False: Autoimmune diseases, in general, can cause lung disease.

Answer 19

True. They can all affect the lungs in the same way RA does.

Question 20

True or False: There is a broad differential diagnosis for hemptysis

Answer 20

True! Hemoptysis can be from many things. Consider thinking about the diagnosis in terms of anatomical location of bleeding.

Question 21

Name the 3 categories/causes of alveolar hemorrhage syndrome

Answer 21

• Pulmonary acpillaritis (vasculitis, connective tissue disease, drugs)
• Bland hemorrhage (CTD, anticoagulants, mitral stenosis)
• Diffuse alveolar damage (infection leading to ARDS, viral pneumonia, drugs)

Question 22

Name 2 localized infections that can lead to hemoptysis

Answer 22

Pneumonia, abcess

Question 23

Name 4 airway issues that can lead to hemoptysis

Answer 23

1. Bronchitis
2. Bronchiectasis
3. Cancer
4. Foreign body

Question 24

Name 3 causes of vascular disease that can cause hemoptysis

Answer 24

1. pulmonary embolism
2. pulmonary arteriovenous malformation
3. elevated PCWP (mitral stenosis, left heart failure)

Question 25

How do you narrow down a hemoptysis differential?

Answer 25

In order to narrow down hemoptysis differential, you need to find overlap between possible causes of hemoptysis and the patients HPI and PMH

Question 26

What technique can you use to identify if the blood is coming from the alveoli?

Answer 26

A CXR will show that there are filling abnormalities. In order to find out if the blood is from the alveoli, you do a bronchoscopy with a bronchoalveolar lavage. Each time you put in fluid and bring it back out, it will either get more bloody or less bloody. If it gets more and more bloody, that means the blood is coming from the alveoli. If it gets less and less bloody, the blood was from a different place (e.g. airway) and was just settling in the alveoli. In the example in the picture, you have increasing bloodiness of the fluid so the blood must be coming from the alveoli

Question 27

Why would an alveolar hemorrhage cause an increased D_LCO?

Answer 27

It's because of the way that D_LCO is measured. For this test, CO is administered to see how much of it gets absorbed by the passing hemoglobin (across the capillaries). However, if there is an alveolar hemorrhage, there is blood in the alveoli that has hemoglobin which will bind the the CO. This will make D_LCO seem increased but in reality, it's just the blood in the alveoli that's picking up the CO giving the increased value.

Question 28

What is goodpasture's syndrome?

Answer 28

It is an idiopathic disease that manifests as diffuse alveolar hemorrhage and rapidly progressive glomerulonephritis. It is mediated by antibodies directed against the glomerular basement membrane. Goodpasture's occurs almost exclusively in smokers

Question 29

True or False: Goodpasture's Syndrome occurs almost exclusively in smokers

Answer 29

True

Question 30

What is inflammatory bowel disease and how can it manifest in pulmonary disease?

Answer 30

Inflammatory bowel disease is an autoimmune disease which attacts the GI tract. In addition to attacing the GI tract, it can affect many different parts of the lung: IBD patients have roughly 5 times more risk of getting pulmonary embolisms bc they are hypercoagulable.

Question 31

What's going on here?

Answer 31

Bronchiectasis. Bronchiectasis is best seen in CT scans. The way that we define bronchiectasis on a CT is to look at airways and their corresponding vessels. Generally, the vessels shoud be bigger than the airways. **If the airways are bigger than the vessels, the patient has bronchiectasis.**

Question 32

Would tracheobronchitis, bronchiectasis, and bronchiolitis give you an obstructive or restrictive pattern of disease?

Answer 32

Obstructive (typically, large airway or bronchi involvement gives obstructive pattern)

Question 33

Would pleural effusion and interstitial lung disease give off an obstructive or restrictive pattern of disease?

Answer 33

Restrictive

Question 34

Which ways can sickle cell manifest in the pulmonary system?

Answer 34

- Infection - Embolisms because of bone marrow infarction and fat emboli - Infarction caused by in-situ thrombosis (from sickling cells obstructing capillaries) - Hypoventilation due to rib and sternal infarctions (pain) - Treatment for sickle cell is hydration but excessive hydration can cause pulmonary edema - Pulmonary hypertension and chronic lung disease are long-term consequences of sickle cell

Question 35

What is acute chest syndrome?

Answer 35

The acute chest syndrome is a vaso-occlusive crisis of the pulmonary vasculature commonly seen in patients with sickle cell anemia. This condition commonly manifests with pulmonary infiltrate on a chest x-ray.

Question 36

How does Acute Chest Syndrome look in CXR?

Answer 36

It looks like pneumonia (filled airspaces) Often appears as bilateral diffuse alveolar and interstitial infiltrates.

Question 37

How do you treat acute chest syndrome?

Answer 37

- Antibiotics for pneumonia (treat for the possibility that infection caused this) - Oxygen supplementation (to alleviate some of the sickling) - Transfusion (to give normal RBC) - Supportive care

Question 38

How can HIV show up with pulmonary complications?

Answer 38

Infectious pulmonary complications from HIV: - Bacterial pneumonia - Tuberculosis - Pneumocytis jirovecii - Fungal pneumonia - Viral pneumonia Noninfectious pulmonary complications from HIV: - Kaposi's sarcoma (capillary malignancy) - Non-hodgkin's lymphoma - Lung cancer - Emphysema - ILD - Pulmonary HTN - Effusions (parapneumonic, TB, malignant) **HIV** causes susceptibility to all of the above.

Question 39

What does CD4 count tell you in HIV patients?

Answer 39

It tells you how immunocompromised the patient is which tells you how likely they are to get infections. If CD4 is normal, you won't get any rare infections. If CD4 is low, you can get any infections.

Question 40

What is this?

Answer 40

This is a skin finding of Kaposi's sarcoma, a malignancy that HIV patients can get. Kaposi's sarcoma is a capillary malignancy which can cause lung problems including infiltrates and hemoptysis.