Sunday, July 27, 2014

A Pulmonary Fibrosis Primer for Doctors

This is a post for health care professionals. Many doctors, nurses, and other health care workers have limited experience with Pulmonary Fibrosis. These are my own recommendations, not those of any organization I am affiliated with. This is not intended as a comprehensive review -- instead I provide highly focused learning points that can be used in clinical practice. 


When should I suspect that my patient might have pulmonary fibrosis?
There are four typical and overlapping presentations of PF:
1. Subacute or chronic cough
2. Exertional dyspnea
3. Concerned patient with a family history of pulmonary fibrosis
4. Incidental PF found on CT imaging

The initial evaluation should include careful chest auscultation for crackles. Please listen carefully halfway down the back at both lung bases as well as in the mid-axillary lines. Drs. Cottin and Cordier have written about the importance of careful auscultation in the early detection of PF. You can listen to crackles online here. If you have access to the NEJM website, you can also listen to crackles here. Examination of the fingers for clubbing can also be helpful in raising the suspicion for PF. 

If crackles or clubbing are present, order the following tests at a minimum:
1. PA and lateral chest x-ray
2. Spirometry and DLCO

I also recommend walking the patient in the hallway briskly for ~200 feet or until dyspnea develops. Check pulse oximetry before and after the walk. A decrease in SpO2 of 3-4% or more indicates exertional desaturation and should raise the suspicion of PF. Performing this informal test on a staircase is probably more sensitive than a hallway walk.

The bottom line is that you should have a low threshold to look for PF. Late diagnosis, early misdiagnosis, and suboptimal management strategies are common. PF should be investigated if there is one historical feature suggestive of PF plus one feature from the physical exam or from preliminary testing. Take a look at the figure below. Dyspnea, cough, or a family history combined with one of the "ACES" findings should be enough to move forward with an evaluation for ILD or PF.



What should I do if I suspect my patient might have pulmonary fibrosis?
If you suspect PF, please order a high-resolution CT scan of the chest. I discussed the details of an HRCT in a previous blog post about lung biopsies. Here is the bottom line: 

  • Supine inspiratory scan with slice collimation no greater than 2 mm (preferably < 1.25 mm)
  • At least a few supine expiratory images should also be performed
  • High spatial frequency reconstruction algorithm ("Bone" recon on GE machine)
  • No IV contrast
Remember, that a CT angiogram is not an HRCT -- yes, the images are thin, but the reconstruction is not "high res. Thin images alone do not make an HRCT.

Ok. There is evidence of ILD/PF on the HRCT. What do I do next?
Based on the HRCT, you have diagnosed your patient with ILD. The next step is to figure out which kind of ILD your patient has. Here's what I do in my practice:

1. Take a thorough history
In addition to establishing the narrative history, asking the usual questions about dyspnea, cough, and exercise tolerance, and the other standard components of a medical history, I find out about the following:
  • History of cancer, chemotherapy, or radiation therapy
  • History of cardiac arrhythmias and amiodarone use
  • History of prostate, urinary, kidney infections and nitrofurantoin (Macrodantin, Marcobid) use
  • All current and prior chronic medications -- don't forget that you can check pneumotox.com to see if your patient's medications might have contributed to their lung condition.
  • Symptoms of connective tissue disease (Raynaud's, rash or other skin changes, joints, finger tip changes, heartburn, regurgitation, dry eyes, dry mouth, morning hand stiffness, muscular weakness or pain)
  • Exposure to mold sources
    • Forced air heating
    • Hot tubs
    • Humidifiers
    • Visible mold, water damage, or musty odors in the home
    • Renovation
  • Exposure to birds in the home or in cages; down pillows or comforters
  • Exposure to farming or argiculture
  • Occupational history with possible dust, fume, vapor, gas, or particulate exposure including:
    • Mining
    • Excavating
    • Quarry work
    • Stone work
    • Foundry work
    • Ceramics
    • Abrasives
    • Heavy metals
    • Asbestos
    • Construction
    • Aerospace industry
  • Family history
    • Anyone with pulmonary fibrosis/interstitial lung disease or sarcoidosis?
    • Anyone ever on oxygen at home?
    • Anyone with "autoimmune" diseases, such as lupus, scleroderma, rheumatoid arthritis, or "myositis"
  • I also ask about snoring and sleep apnea symptoms.
2. Physical exam findings
It is not unusual for me to have a pretty good idea about the specific diagnosis after completing a history and physical exam. Here's what I focus on during the exam:
  • Narrow oral aperture (scleroderma)
  • Heliotrope rash around the eyes (dermatomyositis)
  • Telangiectasias on face & chest (scleroderma)
  • Tightening of the skin on the face, chest, and hands (scleroderma)
  • JVD and hepatojugular reflux
  • Lungs
    • Crackles
    • Squeaks (hypersensitivity pneumonitis and bronchiolitis)
  • Heart
    • RV heave
    • Loud P2
  • Fingers
  • Arms & hands
    • Synovial thickening on MCPs and wrist
    • Joint deformities
    • Rheumatoid nodules
  • Legs
    • Erythema nodosum (sarcoidosis)
    • Pedal edema
  • Muscle tenderness (myositis)
  • Proximal or distal arm or leg weakness (myositis, steroid effect, deconditioning)
3. Serologies and other blood tests
I find rheumatologic serologies to be helpful in quite a few cases. There are certainly many patients I've seen where their rheumatologic serology results helped us avoid a surgical lung biopsy. In many cases, negative serologies help push me to have my patient undergo a surgical lung biopsy. I recommend checking a least a few serologies before performing a surgical lung biopsy.

At a minimum, the following should be checked:
- CBC with differential (for eosinophilic pneumonia)
- Anti-nuclear antibody titer (ANA)
- Rheumatoid factor (RF)
- Anti-cyclic citullinated peptide titer (CCP)

I strongly suggest also performing the following tests in most patients:
- Basic metabolic panel, including calcium
- Creatine kinase (CK)
- Hypersensitivity pneumonitis panel
- Extractable nuclear antibody (ENA) titer (includes antibodies against Scl-70, Jo-1, SSA, SSB, U1RNP, and Smith at my hospital)
- Anti-centromere antibody
- Erythrocyte sedimentation rate (ESR)
- C-reactive protein (CRP)
- Anti-PR3 and anti-MPO antibodies (ANCA antibodies)

Some patients should also have the following tests performed:
- Full myositis panel (if myositis is suspected)
- HIV testing
- Urinalysis and microscopy (for pulmonary-renal syndromes)
- Anti-phospholipid antibodies (anti-cardiolipid antibodies, lupus anticoagulant)
- Anti-RNA polymerase 3 antibodies

All of the tests are back. What do I do know?
Now comes the hard part: you need to combine the history, physical examination, serologies, and HRCT appearance and come up with a unifying diagnosis. If a unifying diagnosis has not been clearly established by this point, you have a few options (listed here from most to least preferred):

Option 1: Refer to an ILD center
I strongly recommend referral to an ILD center -- even for a one-time consultation -- at this point in the evaluation. An ILD center can often help confirm a diagnosis without requiring a surgical lung biopsy. We can also provide guidance on management and help facilitate enrollment in clinical trials. You can find a list of ILD centers on the Pulmonary Fibrosis Foundation's website.

Option 2: Surgical lung biopsy
I think most ILD docs would prefer to provide input before a biopsy is performed, but if you do decide to proceed with a biopsy, please make sure the surgeon takes multiple large biopsies from 2-3 lobes (not just the lingula or middle lobe). Please also have the biopsy reviewed by a pulmonary pathologist with expertise in ILD.

Option 3: Prescribe prednisone
In most cases, I think this is a suboptimal management strategy for ILD that has not been fully characterized. There are some patients (e.g., very sick patients with ILD characterized by ground-glass infiltrates who do not have bronchopulmonary infection) where an "empiric trial" of corticosteroids is reasonable. In most patients, however, this approach clouds the diagnosis, makes subsequent management decisions challenging, and puts the patient at risk for all of the side effects of prednisone (including the 7-fold increased risk of death seen in idiopathic pulmonary fibrosis treated with prednisone).

What else can I do for my patient with PF?

Lots.
  1. Assess oxygen requirements at rest, with exercise, and with sleep. Prescribe oxygen (and instructions on its use) to maintain SpO2 > 90% all the time. Tell your patients to buy a pulse oximeter (less then $30 without a prescription) and monitor oxygen saturations right after exertion. Teach your patients to avoid desaturation by dialing up their flow before they exert themselves.
  2. Prescribe pulmonary rehabilitation
  3. Screen for sleep apnea
  4. Vaccinate for influenza and pneumococcus
  5. Help your patient achieve a healthy weight
  6. Encourage your patient to join a PF support group (including online support groups, like the one at inspire.com).
  7. Refer your patient for clinical trial enrollment
  8. Refer your patient for lung transplantation (it is never too early)
  9. Tell your patient about all of the PF information available online
That's a good start. 

Thanks for reading
Dave Lederer
212-305-8203 






13 comments :

  1. David, I'm going to print this out and take it to my primary care physician. Thank you for all you do.

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  2. This is great information! Thank you so much!

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  3. I was curious about the statement/inference that early diagnosis of PF is important. Certainly I do not feel that going to a Center of Excellence for a couple of years did anything to help me or my quality of life. It did make me feel like someone who knew what they were doing was tracking my disease, but knowing what they were doing didn't equate to any real treatment.

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    1. I am often asked about this.

      ILD centers do things that help their patients: we make accurate diagnoses (which then informs management and prognosis), maximize oxygen prescriptions, enroll patients in pulmonary rehabilitation, move forward with lung transplant evaluation early on when indicated, etc.

      ILD centers can also actively avoid doing things that are harmful: we avoid biopsies of the lung when they are not indicated, and prednisone and other therapies when they might be particularly harmful. Sometimes the best medical care involves avoiding harmful therapies. From the patient's perspective, it might seem like nothing is being done. What would your medical care have looked like if you had not been seeing an ILD doc?

      There is also some published evidence that early access to an ILD center is associated with improved outcomes: www.ncbi.nlm.nih.gov/pmc/articles/PMC3208648/

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    2. I firmly believe that if I had agreed in 2010 to go back to the same local community-based respirologist that I saw in 2005 and 2008 who finally diagnosed me with "sensitive lungs" that I probably would have been put on the combination of prednisone, azathioprine, and N-acetylcysteine (NAC) that was standard treatment, without testing prior to the Panther study, for so many years. I don't believe the community respirologist would have been up to date on the negative results of the Panther study.

      So by going to an ILD clinic, although my HRCT did not clearly show the UIP-pattern, I was treated with suspected IPF but possibly NSIP and therefore no harmful treatment was given. Once my disease was progressing, without any further information to provide an accurate diagnosis, 2 1/2 years later I had my biopsy that confirmed the IPF.

      And again, when I hit another acute exacerbation they sent me for my transplant evaluation. Fortunately by that time I was recovering sufficiently that while deemed suitable, I was too early to list. But I also feel that moving me along the transplant path is a parallel path that I travel while managing my IPF, not the "well nothing more we can do for you" end of the road detour that might have occurred.

      I personally credit the ILD clinic with giving me the best possible management of my IPF and giving me the time.

      The PFF Education Webinar Health Care Professional Focused Webinar - "Making An Accurate Diagnosis: How to Use IPF Consensus Guidelines" - July 16, 2014 is an excellent accompaniment to this blog post (http://pulmonaryfibrosis.org/life-with-pf/pff-educational-resources/webinars/making-an-accurate-diagnosis-how-to-use-ipf-consensus-guidelines).

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  4. Thank you, Dr. Lederer for the wonderful and very informative article. I agree with Barbara - I would like to print this and pass it out every chance I get. Even though this article is geared for health care professionals, patients and caregivers benefit from it as well. I wish this was required reading for every health care provider. Prior to my husband's diagnosis, he had many chest x-rays and CT scans over the course of several years. We have copies of all the reports and they are riddled with many of terms you use in the articles. Our doctor had said on several occasions that he heard crackling. I truly believe that his referral for further testing was due to one radiologist who either knew what he was looking at or looking for. He knew what PF looked like. I think the evidence had been there for quite some time, but this one medical professional knew what he saw. This is why education is so critical and this article is so important. Thank you again for this information.

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    1. Thanks for your kind words, Michele. Very happy this information is useful.

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  5. Hi David. Any chance you'll be at ICLAF in Mont Tremblant?

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  6. Hi Barbara,

    I will be at ICLAF. Looking forward to meeting you there!

    Dave

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  7. Great. I'll be with the Canadian Pulmonary Fibrosis Foundation group. My husband Malcolm and I are staying at the Homewood Suites. Jeff apparently won't be there and never makes them because of the timing. Oh well! I'll get to meet one of the blogging docs ;-)

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  8. Dave... Thank you for providing this. I wanted to let you know that people in the online support groups are printing it and giving it to their doctors. We are all out there helping to advance awareness AND education about PF and it is due to you and other like you who provide things like this so we can help. Taleena...

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    1. That is great to hear, Taleena. I hope docs find it useful.

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  9. Great information thanks for sharing...Pulmonology is a disease related to the chest tract.Pulomonoly is a disease is known to chest medicine and respiratory medicine in some countries. Visit Best Pulmonologist in Gurgaon Delhi to know more about it.

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