PULMONARY BOARD REVIEW:

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PULMONARY BOARD REVIEW:
RARE LUNG SYNDROMES
(NOT DISCUSSED ELSEWHERE)
Parenchymal Disorders:
1. Acute Chest Syndrome
a. Affects approx. 40% of all pts with SCD
b. Most common in children and, when recurrent, can lead to chronic respiratory
insufficiency
c. Defined clinically with chest pain, fever and infiltrates on CXR
d. Causes include infections (Chlamydia pneumoniae and Mycoplasma), in situ
thrombosis, fat embolism (from bone infarction), and hypoventilation secondary
to pain/narcotics
e. Treatment:
i. Transfusion in those with: Hypoxemia and/or resp. distress, h/o cardiac
dz, Significant pain in extremities, Adults, Significant anemia,
thrombocytopenia or multilobar pneumonia
ii. Supplemental O2/Narcotic analgesia
iii. Broad spectrum abx including Macrolide
iv. Long-term tx with hydroxyurea (No role for acute management); causes
increased production of fetal hgb
v. Bronchodilators even in absence of bronchospasm because airway
hyperresponsiveness is frequently present
vi. Incentive spirometry has been shown to reduce pulmonary complications
2. Adult Onset Still’s Dz
a. Still’s dz (Juvenile Rheumatoid Arthritis) is most frequent collagen vascular dz
of childhood. Disease in adults is episodic in nature and occasionally mimicks
sepsis and/or ARDS
b. Salmon Colored Rash; macular rash
c. Pulmonary involvement is commonDiffuse organizing alveolar damage; also
can see pleural effusions and diffuse alveolar infiltrates, mediastinal LAN
d. Pericarditis, hepatitis and glomerulonephritis can occur
e. Other findings include arthralgias, sore throat, leukocytosis
f. Hyperferritinemia helpful in confirming dx
g. Tx is steroids
3. Felty’s Syndrome
a. Extra-articular manifestation of severe rheumatoid arthritis
b. Combination of arthritis, splenomegaly and leucopenia
c. Recurrent local and systemic infectionsLeads to inc. morbidity/mortality
d. Can occasionally present as acute upper airway obstructionAffects vocal cords
4. Familial Mediterranean Fever (FMF)
a. Repeated courses of pleuritis without underlying parenchymal involvement
which resolves rapidly and completely, allowing for good health between attacks;
can be complicated by renal amyloidosis
b. Autosomal recessive; chromosome 16; Pyrin/Marenostrin
c. TxColchicine 1-2mg/d
5. Chronic Granulomatous Dz
a. Refers to 4 genetic diseases (one is x-linked, 3 are autosomal recessive) in which
phagocytes are deficient in respiratory burst oxidase activity. Neutrophils and
other phagocytes are unable to manufacture oxidants such as H2O2 placing
patients at risk of developing recurrent life-threatening bacterial and fungal
infections (most commonly S. aureus, Enterobacter, Aspergillus).
b. Pos. nitroblue tetrazolium test
c. Lung bxgranulomas with microabscesses
d. Can also use flow cytometry with dihydrorhodamine-123 fluorescence for dx
e. TxChronic antibiotic prophylaxis (Bactrim) and subcutaneous injections of
interferon-γ. Acute infections may require allogeneic granulocyte transfusions.
Systemic steroids may be required for a few weeks to resolve granulomatous
process
6. Acute Mountain Sickness (AMS)
a. Most common high altitude syndrome
b. Manifests within 12-96 hours after ascent
c. h/a, fatigue, malaise, anorexia, nausea, sleep disturbance
d. If severe, can manifest as pulmonary and cerebral edema
e. HAPE (High Altitude Pulmonary Edema)develops within 24 hrsfever,
leukocytosis, severe hypoxemia and diffuse alveolar infiltrates on CXR
f. Risk factors for HAPE: Prior AMS, Younger age, male gender
g. Prevention of AMS
i. Gradual ascent and acclimatization at 2000 meters
ii. Prophylactic slow release Nifedipine (20mg q8h) demonstrated to
significantly reduce incidence of HAPE in susceptible climbers above
3700 meters
iii. Acetazolamide (250mg q8h or 500mg q12h) is effective in preventing
AMS by increasing nocturnal VE and preventing hypoxemia. Give 24-48
hrs prior to ascent and continue for 3 days of acclimatization
iv. Dexamethasone  2nd line therapy of established HAPE  Not
recommended as preventative therapy
h. Most effective tx of HAPE  Descent to lower altitude
7. Alpha 1 Antitrypsin Deficiency:
a. Made in the liver and circulates in blood
b. Mostly northern europeans
c. Hereditary deficiency – minor changes in gene coding produces alterations in
structure of protein – more than 75 alleles detected
i. Each allele has a name – preceded by Pi (protease inhibitor)
ii. Everyone has two genes coding – maternal and paternal origin
iii. Normal = PiMM (200 mg/dL)
iv. PiZ – impaired transport from liver  accumulates in liver and causes
destruction there
v. PiZZ (homozygous) – have 15% of normal (30 mg/dL)
vi. PiMZ (heterozygous) – have 50-60% of normal
d. PiZZ – strong risk factor for premature emphysema (30-40 yo), particularly if
smoker
e. Structural integrity of alveolar wall depends on balance b/w elastin degradation
by elastase (released by PMNs and MPs) and protection by A1AT
f. Panacinar emphysema – predominant in lower lung zones
g. Tx:
i. NO smoking!!!
ii. Replacement therapy with Prolastin (pooled human plasma A1AT) –
(Wewers NEJM, 1987; 316:1055-1062) – once weekly 60 mg/kg weekly
for those with established emphysema – airflow obstruction (ATS
guidelines) – well tolerated, expensive
iii. No definitive randomized controlled trial
iv. Don’t treat = liver disease, elderly, smokers
v. Give HBV vax first – from pooled plasma
8. Lung Transplant:
a. Acute Rejection: fever, dyspnea, cough
i. First 3 months: abnormal CXR with peri-hilar infiltrate
ii. > 3 months: usually normal CXR
iii. perivascular lymphocytic infiltrate
b. Chronic Rejection: B.O. (bronchiolitis obliterans), > 3 mths post TPx,
worsening obstruction
c. PTLD: homogenous proliferation of lymphocytes – NHL and B type
i. Develop in first year
ii. Associated with EBV – primary or reactivity
iii. If EBV negative prior to TPx  increased risk
iv. Solitary to multiple pulmonary nodules
v. Affects allograft and occasionally extra-pulmonary (CNS)
vi. Tx: decrease immunosupression, XRT/chemo, acyclovir, ganciclovir,
alpha interferon, lymphocyte activating killer cells
9. Hamartomas:
a. Most common benign lung tumor and account for 5-10% of all SPN’s
b. Malignant change is extremely rare
c. Central cartilaginous area with other areas of myxomatous and fibroblastic tissue,
muscular, adipose tissue, bronchial glands
d. Typically well circumscribed, < 3 cm, lobulated
e. Calcification in 10-15% (better seen on chest CT, cartilage or fat deposits) popcorn pattern
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