Diffuse Parenchymal Disease Flashcards
IPF Pathogenesis
- Must have susceptible host:
- Genetics: MUC5B, TERC/TERT/TOLLIP
- Short telomeres
- Cellular senescence
- GERD
- Microbiome - Injury to the lung
- GERD, Smoking, Occupational exposure - Abberant repair
- Fibrosis - FGF- TGF-B, PDGF ETC
IPF Histology
Basilar and pleural predominance
Microscopic honeycombing
Temporal heterogeneity (abnormal lung and normal lung are adjacent)
Fibroblast Foci
RB-ILD
- Symptoms
- HRCT
- Histopathology
Symptoms:
- Subacute onset of cough, sputum production and SOB
HRCT:
- Air trapping
- Centrilobular GGO
- Upper lobes
- Bronchial wall thickening
Histo:
- bronchiolitis (indistinguishable from other Bronchiolitis- however RB-ILD if impairment on PFTs and on imaging)
- no fibrosis
- Pigmented (Tan) Macrophages
RB- ILD Treatment
Smoking cessation
- Mortality rate is very low
ILD associated with DM/PM/Anti-synthetase syndromes
- Symptoms
- Antibiodies
- ILD presentation
Symptoms:
- Helitrope rash
- Shawl sign
- Mechanics hands
- Grotton nodules
- Proximal muscle soreness/weakness
Antibodies
- Anti Jo/Mi - DM/PM
- Anti Synthetase:
——- anti-tRNA aminoacyl transferases
——- Anti PL12
——- Anti PL 7
Of note
- If Anti-Jo then much more likely to have ILD
- If Anti-PL 12- may have ILD without myositis
- If Anti MD5 - DM without myositis but Progressive ILD
HRCT findings of ILD due to Myopathy:
- NSIP
- OP, UIP, DAD
Progressive Pulmonary Fibrosis Criteria
Non-IPF pulmonary fibrosis with ⅔ of the following:
1. increased respiratory symptoms
2. Decrease DLCO by 10% or Dec in DLCO by 5% or more.
3. New/worsening CT findings (Increased volume loss, inc GGO, inc. bronchiectasis, inc. or new reticulations)
Young Adult Smoker with spontaneous PTX complaining of cough and dyspnea.
May have other constitutional sx
- Imaging
- PFTs
Pulmonary Langerhans Cell Histiocytosis
Imaging:
- Upper lobe predominant
- Nodules and Cysts (cavitation) of abnormal shape
- Basilar sparing (sparing of CP angles)
PFTs: Restrictive, obstructive, mixed. Reduced DLCO
Diagnosis of PLCH
BAL: > 5% CD1a diagnostic
Gold standard: Biopsy
- S100 stain positive on
- BRAF V600E
- MAPK
- Eosinophils and abnormal histiocytes with abnormal nuclei
Management of PLCH
Smoking cessation
BRAF Inhibitors (if BRAF mutation present)
Cobimetibinib/MTX/Cytrarabine
Lung transplant (will re-curr)
Screen for pulmonary hypertension- high risk
Variable prognosis, also with increased risk of malignancy.
LAM
- patient profile,
- HRCT,
- Dx
- Biomarkers
- Treatment
Women of child bearing age, with spontaneous PTX or renal angiomyolipoma. Or some with Tuberous Sclerosis.
LAM cells (similar to smooth muscle cells- ATYPICAL) proliferate along the lymphatics, bronchovascular bundles
HRCT: thin walled- regular cysts that favor the periphery. Preserved interstitum- just cysts.
DX with CT and biopsy
LAM cells, HBM 45+, elevated VEGF (>800)
PFTs: DLCO decreased, obstructive then later restrictive
Treatment: Siromilus, and transplant
LIP
Patient Profile:
Women with Immunodeficiency or CTD
- Sjorgrens
- CVID, HIV
Symptoms:
- Cough, dyspnea plus constitutional sx \, pleuritic chest pain
Due lymphocyte and plasma cell infiltration of the interstitial and bronchovascular bundles. Therefore on
HRCT:
- Thickened septum, centrilobular nodules, GGOs, and cysts of varying shapes and sizes (thin walled)
Pathology:
- Non-necrotizing granulomas and lymphocyte and plasma cell proliferation.
PFT: Reduced DLCO with restriction, preserved air flow
Dx: CT and biopsy
Treatment:
- Steroids
Of note
- may transform into lymphoma - maltoma- slow growing
- people die within 5 years of diagnosis
Pulmonary Benign Metastasizing Leiomyoma
Patient profile:
- Patient with cough, shortness of breath
- hx of hysterectomy etc
HRCT:
- Numerous, well circumscribed random nodules
- Nodules may cavitate
- PET negative - low metabolic activity (benign tumors)
Dx:
- histopathology only way to diagnose
- uterine well-differentiated spindle-shaped cells with low nuclear and cellular variance in size and shape
- A low mitotic index of fewer than five mitoses per 10 in a high-powered field,
- These tumors are also diffusely and strongly positive for estrogen and progesterone receptors and negative for HMB-45.
Pulmonary Manifestations of IBD
Pulmonary and GI manifest from the same area- foregut. Therefore if affects GI tract can affect the lungs
Pneumonitis from immunosuppressive
Infection from immunosuppressive
Inflammation :
– eosinophilic nodules
– lymphocytic nodules
– non cascading granulomas
Most common:
- Bronchitis
- OP with eosinophilix/lymphocytic or ncg on biopsy
- bronxhiectasis
- affects upper and lower lobes
Rule out infection
organizing Pneumonia
Fevers, chills, malaise, weight loss
Subacute
HRCT:
- Lower lobe/middle lobe
- GGO and consolidation favouring the peribronchovascular areas and subpleural (peripheral)
- Atoll (reverse halo sign)
- migratory
BAL:
- lymphocytic (20-40%), NT (10%)
- CD4/CD8 ratio decreased
Biopsy:
- Masson bodies - endoluminal fibroblast and collagen deposits that are well organized.
Treatment:
- steroids
CTD related lung disease
Outside in
1. pleural: pleuritis, pleural effusion, ptx
2. parenchyma: fibrosis, nodules, bullae
3. airways: bronchiectasis, bronchiolitis
4. Vascular: pHTN, or vasculitis
5. other: amyloid, MSK weakness
