What is the general distribution of ILD's based on age?
Youth: Sarcoidosis & Collagen vascular diseases
Older: smoking-related ILD's/IPF
How do PFT's look w/ ILD's?
Normal or High FEV1/FVC ratio
Low FEV1 and FVC
Low TLC *confirms restriction*
Low DLCO (non-SP)
What is Raynaud's Phenomenon?
Exaggerated vascular response to cold T & emotional stress
Px w/ sharply demarcated color changes of skin/digits
What condition is Raynaud's Phenomenon closely associated w/?
What Tx may be given for Raynaud's Phenomenon but why might this require monitoring?
Prostaglandin infusions may be req to restore flow but may req monitoring for hypotension
What lab work is req if Scleroderma is suspected?
Antiscleroderma ab's: Anti Scl 70 & Anticentromere ab
Is a biopsy necessary for autoimmune dx like Scleroderma?
No bc often clinical picture, radiology & lab testing suffice
Biopsy may hurt more than help, especially in impaired healing
How does Systemic Sclerosis differ from Limited Scleroderma?
Limited: Pulmonary HTN
What is Systemic Sclerosis (Scleroderma)?
Autoimmune disease; heterogeneous group of conditions linked to thickened, sclerotic skin lesions
Pulmonary inv in >80%
What other systems might be affected by Scleroderma?
What is a pathognomnic CXR finding for Pulmonary Alveolar Proteinosis?
What is the difference between honey combing & crazy paving?
Honey-combing is more basal & peripheral involving stacks of cells; larger than alveolar spaces bc lungs are destroyed; ground glass appearance
Crazy-paving: more central; CXR also w/ hyper-dense opacification
What is Pulmonary Alveolar Proteinosis?
Diffuse lung dis w/ accumulation of amorphous periodic acid Schiff (+) lipoproteinaceous material in distal air spaces
What is a unique ft of Pulmonary Alveolar Proteinosis?
Little to no lung inflammation, underlying lung architecture preserved
What is the lipoproteinaceous material in PAP made of?
Surfactant phospholipid and apoproteins
What signaling and players are involved in preventing PAP?
Macrophages aided by Granulocyte Macrophage Colony Stimulating Factor (GMCSF) to mop up surfactant and avoid excess
What is the infectious agent most commonly associated w/ PAP?
Nocardia: Gram (+), catalase (+) rod shaped bacteria- risk of infection!
What is congenital PAP?
Disorders of surfactant production
What is secondary PAP & what are its 4 causes?
1) High dust exposure (ie: silica, Al, Ti)
2) Hematologic dyscrasia (ie: myelodysplastic syndrome, malignancy)
3) After allogeneic hemtaopoietic cell transplantation for myeloid malignancies
4) Rel deficiency of GM-CSF and related macrophage dysfunction
What are complications of PAP?
Hypoxemia, Dyspnea, & RF
How does pulmonary alveolar proteinosis present histologically?
Alveolar spaces filled w/ pink lipoproteinaceous surfactant, w/o inflammation and architecture preserved
How is PAP treated?
Treat underlying cause!
If GMCSF is 10 problem, replace it via inhalation
Serial bronchoalveolar lavage: wash out lipoproteinaceous products
How might cystic lung disease present acutely?
How does Lymphangioleiomyomatosis (LAM) appear on CT?
Diffuse cysts of uniform shape
What is Lymphangioleiomyomatosis (LAM) & who does it affectly primarily?
Rare multisystem disorder that affects lungs w/ characteristic cysts (but also kidneys); primarily of young women
What is the primary histopathological abnormality in LAM?
Proliferation of atypical SM (LAM) cells
What factor plays a key role in LAM pathogenesis?
Hormonal fluxes (ie: pregnancy, exogenous estrogens)
What role does genetics play in LAM pathogenesis? What might these genes induce?
Excessive proliferation of LAM cells due to mutations in tuberous sclerosis complex (TSC) genes, esp TSC2
TSC can form multiple benign tumors in many systems->seizure, epilepsy
What are the Tx's of LAM?
What immunosuppressive can stabilize LAM?
Sirolimus (mTOR inhibitor that blocks T cell activation and B cell differentiating by preventing IL-2 response)
What might a LAM lung's gross appearance look like?
Cysts in gross specimen
How does LAM present histologically?
Abnormal SM proliferation & spindle shaped SM cells all over lung
What does LAM stain w/?
HMB45: melanoma stain
Brown= abnormal LAM/SM cells
What does Langerhans Cell Histiocytosis (LCH) look like on CT?
w/ bizarre shaped cysts & nodules, less regular than LAM
What is Langerhans Cell Histiocytosis (LCH)?
Rare histiocytic disorder most commonly characterized by single or multiple osteolytic bone lesions w/ infiltration w/ histiocytes having bean-shaped nuclei on biopsy
What systems might LCH affect?
Histiocytes, lymphocytes, macrophages & eosinophils may infiltrate every organ (skin, lymph nodes, lungs, thymus, liver, spleen, BM, CNS)
What systems does LCH spare?
Heart & kidneys
What is the origin of pathologic Langerhans cells?
Myeloid dendritic cells
What features lead to a characteristic Dx of LCH that a biopsy may not even be req?
High resolution CT w/ multiple cysts & nodules w/ mid-upper zone predominance and intersitial thickening in a young smoker
How does LCH present histologically?
Langerhans cells w/ bean shaped nuclei
Another name- "Eosinophilic Granuloma"
What is the Tx for smoking related ILD's?
What are the Tx's for ILD's associated w/ CT disorders, Sarcoidosis, Radiation/Drug Exposure, HP, NSIP pattern?
Steroids may be useful but treat underlying dis & avoid exposure
What are Tx's for Pneumoconioses?
Trick qt- N/A!
What are Tx's for IPF?
Smoking cessation, newer agents (antifibrotics), transplant