Clinical Medicine - Pulmonology

Honeycombing

clustered cystic air spaces that are usually subpleural, peripheral, and basal in distribution

Traction bronchiectasis

describes dilation of bronchioles

Ground glass opacities

area of increased attenuation in the lung with preserved bronchial and vascular markings

Nodular opacification

broad patterns of pulmonary opacification

pulmonary nodule, airspace nodule, or part of underlying reticulonodular pattern

Alveolar ventilation (V)

the amount of air that reaches the alveoli (liters/min)

Perfusion (Q)

pulmonary blood flow (liters/min)

Physiologic shunt

poorly ventilated alveolus leads to poorly oxygenated blood returning from the lungs

Physiologic deadspace

impaired blood flow to alveoli

VQ mismatch: shunt causes

pneumonia

pulmonary edema

tissue trauma

atelectasis

VQ mismatch: dead space types

anatomic - fixed

physiologic - shock, emphysema, pulmonary embolism

Respiratory dysfunction impact on MSK

respiratory alkalosis --> muscle weakness --> suppression of ventilations

Respiratory dysfunction impact on cardio

chronic lung disease --> pulmonary hypertension --> right sided heart failure

Respiratory dysfunction impact on neuro

hypercapnia --> somnolence/lethargy --> increased cerebral blood flow/CSF pressure/seizures/papilledema

Hypoxia in general will cause

ischemia/infarction of cells/tissues/organs

Obstructive pulmonary diseases

conditions that make it hard to exhale all the air in the lungs

increased RV

ex. COPD, asthma

Restrictive pulmonary diseases

conditions that make it hard to fully expand the lungs with air

decreased TLC

ex. interstitial lung disease, neuromuscular disease, scoliosis, marked obesity

Interstitial lung disease

group of disorders with common characteristics

Interstitial lung disease S&S

progressive gradual onset dyspnea

nonproductive chronic cough with or without hemoptysis

bibasilar late inspiratory crackles

tachypnea

digital clubbing

Interstitial lung disease diagnostics

CXR or CT: reticulonodular ("net like) changes, septal thickening, honeycombing, could also be normal

Lung biopsy (VATS)

PFT

Interstitial lung disease causes

environmental or occupational exposure: pneumoconiosis

autoimmune like Sjogren's, systemic sclerosis, RA

medications: amiodarone, nitrofurantoin, methotrexate

idiopathic: most common

FEV1/FVC < 70%

obstructive lung disease

FEV1/FEV > 70%

restrictive lung disease

Idiopathic fibrosing interstitial pneumonia

most common type of interstitial lung disease

combination of inflammation and fibrosis - NOT infectious

sporadic or genetic

Idiopathic fibrosing interstitial pneumonia treatment

pulm referral

corticosteroids trial

Usual interstitial pneumonia (UIP) treatment

NO steroids

immunosuppressants - nintedanib and pirfenidone to reduce rate of decline

definitive treatment - lung transplant with 5 year survival

Pneumoconiosis etiology

chronic fibrotic lung disease due to inhalation of inorganic dust particles: silica, asbestos, coal dust, beryllium, talc, fiberglass, cement, metals

can occur years after initial exposure

Pneumoconiosis diagnosis

diffuse nodular opacities on imaging

based on history/exposure

no biopsy needed

Pneumoconiosis treatment

supportive and supplemental O2

pulmonary rehab

Coal worker's pneumoconiosis etiology

ingestion of inhaled coal dust by alveolar macrophages --> forms coal macules

Coal worker's pneumoconiosis S&S

often asymptomatic with PFTs unremarkable

more complicated: productive cough with black pigment, wheezing, end inspiratory crackles

mimics COPD

Coal worker's pneumoconiosis imaging

diffuse small fibrotic opacities from coal macules

Coal worker's pneumoconiosis treatment

supportive

Pneumoconiosis: silicosis etiology

silica particle inhalation --> alveolar macrophage dysfunction --> inflammation and fibrosis --> silicotic (small rounded opacities) nodule formation throughout the lung

Pneumoconiosis: silicosis epidemiology

sandblasters

exposure to rocks and sand

Pneumoconiosis: silicosis S&S

asymptomatic with PFTs without change

complicated: dyspnea on exertion, dry cough

Pneumoconiosis: silicosis diagnostics

CXR: multiple nodules in the middle and upper lungs bilaterally, enlargement of hilar and mediastinal lymph nodes

PFTs: later stages show restrictive physiology

Pneumoconiosis: silicosis treatment

supportive - oxygen, vaccines, treat infections, pulm rehab

lung transplant with 6-7 year survival

prevention education

Pneumoconiosis: asbestosis

nodular interstitial fibrosis in workers exposed to asbestos fibers

Pneumoconiosis: asbestosis epidemiology

workers in shipyard, construction, pipe fitters, insulators

10-20 years of exposure

smoking increases risk

Pneumoconiosis: asbestosis S&S

progressive dyspnea

inspiratory crackles

clubbing

cyanosis

Pneumoconiosis: asbestosis diagnostics

CXR: pleural plaques

CT: parenchymal fibrosis and pleural plaques

PFTs: restrictive dysfunction, reduced diffusion capacity

Pneumoconiosis: asbestosis treatment

supportive

smoking cessation!

Pneumoconiosis: berylliosis

chronic beryllium disease (CBD)

granulomatous (clusters of WBCs) disease caused by exposure to beryllium - inhaled or skin

Pneumoconiosis: berylliosis etiology

beryllium exposure --> T-cell sensitization --> immune response with further exposure --> aggregation of immune cells (macrophages and CD4 cells) --> noncaseating granulomas and fibrosis

Pneumoconiosis: berylliosis epidemiology

working history in metal shops, defense industries, jewelry making, electronics industry

Pneumoconiosis: berylliosis S&S

infectious appearance:

fever

weight loss/night sweats

dry cough

LA and hepatosplenomegaly

crackles

rash

Pneumoconiosis: berylliosis differential

similar presentation to TB, but TB has caseating granulomas and necrosis

Pneumoconiosis: berylliosis diagnostic criteria

must meet 3 criteria:

exposure history

positive beryllium lymphocyte proliferation test (BeLPT test) via blood or bronchoalveolar lavage

compatible histology with granulomatous inflammation on biopsy

Pneumoconiosis: berylliosis imaging

XR: nonspecific - normal, can show hilar LA, ground-glass opacities, or interstitial fibrosis

CT: nonspecific, can show parenchymal nodules, ground-glass, opacities, pleural thickening, hilar LA

Pneumoconiosis: berylliosis treatment

vaccines

smoking cessation

corticosteroids if symptoms

if steroids fail: methotrexate and folic acid

supplemental O2

monitor PFTs

trend imaging

Sarcoidosis

systemic disease with granulomatous inflammation of lung but can also affect skin, eyes, heart, and liver

Sarcoidosis epidemiology

North American Black or northern European White people

onset in 3rd-4th decade

Sarcoidosis S&S

fever, malaise

insidious onset of dyspnea

skin with erythema nodosum or Lupus pernio

iritis

peripheral neuropathy

cardiomyopathy

asymptomatic

LA, hepatosplenomegaly, parotid enlargement

Lupus pernio

rare cutaneous manifestation of sarcoidosis on nose, ears, or face

Erythema nodosum

tender nodules on the extensor surfaces of legs

sign of sarcoidosis

Sarcoidosis labs and diagnostics

labs: leukopenia, elevated ESR, hypercalcemia, elevated ACE

PFTs: restrictive

ECG: heart block, dysrhythmia (A fib)

Sarcoidosis radiographs with staging

stage 1: b/l hilar adenopathy

stage 2: hilar adenopathy, parenchymal involvement

stage 3: parenchymal involvement only

stage 4: advanced fibrotic changes in upper lungs

Sarcoidosis diagnostic criteria

clinical/radiographic changes + exclusion of similar dx + histologic changes of noncaseating granulomas on biopsy

Sarcoidosis treatment

asymptomatic - none

symptomatic - prednisone for months-years

immunosuppressive meds if steroid intolerance: methotrexate, azathioprine, infliximab

long term follow up to monitor liver/renal function and PFTs

ophth referral and cardio referral

Sarcoidosis prognosis

hilar adenopathy - best outlook

erythema nodosum - good outcome

lung parenchymal involvement - worse prognosis

Pulmonary nodule aka

coin lesion

Pulmonary nodule

rounded opacity outlined by normal lung

not associated with infiltrate or atelectasis

<3cm

What could pulmonary nodule be?

risk of malignancy

benign lesion

infectious granuloma

inflammatory

Hamartoma

most common benign neoplasm

Solitary pulmonary nodule found on imaging. What's next?

determine biopsy vs resect vs observe

imaging to determine comparison to old imaging studies, estimated growth, size, and appearance

Risk factors for malignancy of solitary pulmonary nodule

increases with age

smoking

prior malignancy

Growth rate of solitary pulmonary nodule

rapid growth (2x size over 30 days) - infection suggested

long-term stability - benign

Size and likelihood of malignancy of solitary pulmonary nodule

<5mm 1%

6-10mm 25%

11-20mm 33%

21-45mm 80%

Benign appearance of solitary pulmonary nodule

smooth, well defined edge

Malignant appearance of solitary pulmonary nodule

ill-defined margins or lobular appearance

spiculated margins and peripheral halo

cavitary lesions with thick walls

Probability of Malignancy and Treatment Guidelines - prediction models

Brock model

VA cooperative model

Low probability of malignancy of solitary pulmonary nodule (less than 5%) approach

observation

serial CT imaging studies

High probability of malignancy of solitary pulmonary nodule (more than 60%) approach

resection following staging if surgical risk is acceptable

biopsies rarely yield a specific benign diagnosis

Intermediate probability of malignancy of solitary pulmonary nodule (5-60%) approach

PET scan

biopsy with transthoracic needle aspiration (TTNA), bronchoscopy with biopsy, sputum cytology, or surgical biopsy

PET/CT scan

positron emission tomography with high sensitivity and specificity but false positives can occur with infection/inflammation

uses fluorodeoxyglucose (FDG) uptake

____ activity on PET scan increases the likelihood of malignancy

Hypermetabolic (positive)

PET scans are not reliable for

brain

Sputum cytology

highly specific but lasts sensitivity

used for central lesions and in patients who are poor candidates for invasive diagnostic procedures

Surgical biopsy of solitary pulmonary nodule is done via

video-assisted thoracoscopic surgery (VATS)

nodulectomy via wedge resection

send to pathology for frozen section to determine if lobectomy

Lung cancer screening recommendations

annual low dose CT (LDCT) in patients age 50-80 with 20 pack year smoking history and currently smoke or quit within the past 15 years

screening discontinued once a person has not smoked for 15 years or develops health problem that limits life expectancy or willingness to complete curative surgery

Lung cancer screening patient education

discuss benefits, limitations, and harms of screening

refer to center with expertise for screening

smoking cessation

Bronchogenic carcinoma

malignant neoplasm arising from respiratory epithelium - cells most exposed to air

Bronchogenic carcinoma etiology

repeated exposure to carcinogens that induces gene mutations in respiratory epithelial cells

mutated cells divide at increased, uncontrolled rate and tumor (nodule/mass) forms

Lung cancer epidemiology

most common cancer death among men and women

cigarette smoking causes 85-90%

Other risk factors for bronchogenic carcinoma

second hand smoke

asbestos

radon gas

metals

radiation exposure

genetics

pulmonary fibrosis, COPD, sarcoidosis

previous lung cancer

Median age of diagnosis of bronchogenic carcinoma

71

Histologic categories of lung cancer

small cell lung cancer (SCLC)

non small cell lung cancer (NSCLC) - adenocarcinoma, SCC, large cell carcinoma

tissue also tested for driver mutations: EGFR, ALK, BRAF, ROS1 to determine targeted systemic therapy

Bronchogenic carcinoma - Small cell carcinomas

arises from neuroendocrine cells

begin centrally causing narrowing of the bronchus w/o discrete luminal mass - extrinsic masses

regional or distant metastasis with early hematogenous spread

aggressive course with median survival of 6-18 weeks w/o treatment

associated with paraneoplastic syndromes

Bronchogenic carcinoma - Adenocarcinoma

arises from alveolar type 2 cells within distal or terminal bronchioles

peripheral nodules or masses

"puckering" of overlying pleura

Bronchogenic carcinoma - adenocarcinoma in situ

spread along pre-existing alveolar structures

characterized by lepidic growth pattern w/o evidence of invasion

Bronchogenic carcinoma - Squamous cell carcinoma

arises from bronchial epithelium

presents with intraluminal mass

centrally located

more likely to present with hemoptysis

large tumors can undergo central necrosis and cavitary lesions

Bronchogenic carcinoma - large cell carcinoma

heterogenous group of undifferentiated cancers that share large cells

aggressive!

Bronchogenic carcinoma symptoms

decreased appetite and weight loss

cough and hemoptysis

SOB

pain

hoarseness

neuro sx if brain mets

Bronchogenic carcinoma signs

LA

clubbing

abnormal breath sounds or pleural effusion

dullness to percussion

bony tenderness

palpable soft tissue mass if metastasis

focal neuro signs

Bronchogenic carcinoma on imaging

post obstructive pneumonia/pleural effusion - endobronchial lesion or extrinsic compression

Why might hoarseness occur in bronchogenic carcinoma?

vocal cord dysfunction from recurrent laryngeal neve paralysis from tumor or lymph nodes

Superior vena cava syndrome

tumor pressing on SVC - oncologic emergency

Pancoast syndrome

malignant neoplasm of superior sulcus invades thoracic inlet brachial plexus and cervical sympathetic nerves (stellate ganglion)

Pancoast syndrome S&S

severe shoulder pain with radiation

atrophy of hand/arm muscles

Horner syndrome

facial/neck edema

Paraneoplastic syndromes

disorders that accompany benign or malignant tumors

NOT directly related to mass effects or invasion

patterns of organ dysfunction related to immune-mediated or secretory effects of neoplasms

small cell lung cancer