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UIP, NSIP and their differential diagnoses

Professor Andrew G Nicholson, DM, FRCPath

Consultant Histopathologist, Royal Brompton and Harefield NHS Foundation Trust, and Honorary Professor of Respiratory Pathology National Heart and Lung Division Imperial College, London, United

Kingdom

Belfast Pathology

Belfast

Tuesday 20th June 2017

Usual InterstitialPneumonia (UIP)

Histologic features of UIPKey Histologic Features

• Dense fibrosis causing remodeling of lung architecture with frequent “honeycomb” fibrosis

• Fibroblastic foci typically scattered at the edges of the dense scars• (TEMPORAL HETEROGENEITY)• Patchy lung involvement• Frequent subpleural, paraseptal and/or bronchovascular distribution

Pertinent Negative Findings• Lack of active lesions of other interstitial diseases (i.e. sarcoidosis or

Langerhans cell histiocytosis• Lack of marked interstitial chronic inflammation• Granulomas: inconspicuous or absent• Lack of substantial inorganic dust deposits, i.e., asbestos bodies (except for

carbon black pigment)• Lack of marked eosinophilia

MINOR HISTOPATHOLOGICAL FEATURES IN USUAL INTERSTITIAL PNEUMONIA

NORMAL

Dense scarDense scar

Micro Honeycombing

THIS IS UIP

Fibroblast focus

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UIP diagnostic here

Eventual outcome

for the lobule

Lobule destroyed

Revised ATS/ERS IIP Classification(to be viewed as a supplement to the 2002 document)

Am J Respir Crit Care Med 2013; 188: 733-748

Clinical Radiologic Pathologic DiagnosisIdiopathic Pulmonary Fibrosis

Idiopathic Nonspecific Interstitial Pneumonia

Respiratory BronchiolitisInterstitial Lung DiseaseDesquamative Interstitial

PneumoniaCryptogenic Organizing

PneumoniaAcute Interstitial Pneumonia

• Rare IIP• Idiopathic LIP• Idiopathic

pleuroparenchymal fibroelastosis

• Rare Histologic Patterns• Acute fibrinous &

organizing pneumonia• Bronchiolocentric

patterns of IP • Unclassifiable IIP

†Reddy TL et al: ERJ 2012;40:377-385

CO-EXISTING PATTERNS IN IPsPLEUROPARENCHYMAL FIBROELASTOSIS AND UIP

NSIP

LIP

UIP RB DIP

OPDAD

= IPF in most cases= Smoking-related IP

= 1ary very rare

= COP or 2ary causes

……AE of IPF

Histologic pattern of UIP in non-IPF patients.

§ Most are seen in the context of IPF but…

§ Chronic Hypersensitivity Pneumonitis (EAA)

§ Collagen Vascular Disease (RA, PM, SS)

§ Asbestosis

§ Familial Idiopathic Pulmonary Fibrosis

§ Drug Toxicity (Usually cytotoxic drugs)

UIP and chronic HP§ Pathologic patterns and survival in Chronic HP.§ Churg et al. AJSP 2009;33:1765

§ 24 subacute (cellular, nonfibrotic) and 25 chronic (fibrotic) HP.

§ 72% chronic HP = UIP-like; § three BIP/F; § 16% F-NSIP§ Only 2 UIP-like cases could not be morphologically

distinguished from idiopathic UIP.

§ Survival for patients with no fibrosis = 22.4 years§ Fibrotic NSIP = 2.1 years; § UIP-like pattern = 2.8 years

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Chronic HP versus UIP/IPF….

Patient subset All patients

Placebo Bosentan

Diagnosis of IPF/UIP by local pathologist

99 50 49

All cases reviewed by the central pathology panel

86 45 41

Cases confirmed as IPF/UIP by central pathology panel

64 36 28

25% of cases rejected as not UIP by reference pathologists

50% F-NSIP 23% EAA (8% in total)

BUILD 1 drug trial

Pathologic patterns and survival in chronic HP. Churg et al. AJSP 2009;33:1765

Histopathologic pattern and clinical features of rheumatoid arthritis-associated interstitial lung disease

Lee HK et al. Chest 2005;127:2019-27

§ UIP – 10, NSIP - 6, and airway disease/OP -2. § In three patients, ILD preceded RA; 3 simultaneous diagnosis

UIP NSIP § Male/female 8/2 0/6§ Smoking Hx 8/2 0/6§ Death 5/10 0/6

Interstitial pneumonia in RATansey D et al. Histopathology 2004;44:585-596

§ Pulmonary fibrosis seen in about <5% of patients§ NSIP and follicular bronchiolitis are commonest histologic patterns, often

superimposed in Brompton experience.§ Early studies suggest survival similar to ‘idiopathic’ NSIP

Usual interstitial pneumonia in asbestos-exposed cohorts - concurrent idiopathic

pulmonary fibrosis or atypical asbestosis? Attanoos RL, Alchami FS, Pooley FD, Gibbs

AR. Histopathology. 2016 ;69:492-8

§ >25 000 persons to the UK Pneumoconiosis Unit, Cardiff.

§ Over the 17-year period, 233 subjects were identified; 210 had f-NSIP and subpleuralaccentuation, and three showed UIP.

§ All three of these cases showed grade 4 fibrosis (honeycombing) with no asbestos fibre dose-response correlation.

§ A Poisson distribution of probability analysis indicated that the observed cases of UIP in this workforce could be wholly accounted for by the prevalence of idiopathic pulmonary fibrosis (IPF) in the population.

§ CONCLUSIONS: § UIP pattern fibrosis is rarely observed in

asbestos-exposed subjects, and shows no dose-response correlation with asbestos fibres on mineral analysis; this points to an alternative disease, such as IPF

§ Interstitial fibrosis and asbestos bodies (2 or more per 1cm2 in a normal thickness section.

1. Interstitial fibrosis of asbestosis is accompanied by very little inflammation, which, although not marked, is better developed in idiopathic pulmonary fibrosis.

2. In keeping with the slow tempo of the disease, the fibroblastic foci that characterize idiopathic pulmonary fibrosis are infrequent in asbestosis.

3. Asbestosis is almost always accompanied by mild fibrosis of the visceral pleura, a feature that is rare in idiopathic pulmonary fibrosis.

Pathology of asbestosis- An update of the diagnostic criteria: Report of the asbestosis

committee of the college of americanpathologists and pulmonary pathology

society. Roggli VL et al. Arch Pathol Lab Med. 2010 Mar;134(3):462-80

UIP AND ASBESTOSIS

Asbestos exposure increases the incidence of histologically confirmed usual interstitial

pneumonia. Kawabata Y et al. Histopathology. 2016;68:339-46.

§ 1718 cases (1202 males; mean age 66.7 years) who underwent lobectomy for resection of pleuropulmonary tumours.

§ 183 with asbestos exposure, and 239 with histological UIP.

§ The 183 cases with asbestos exposure had higher rates of positive occupational history and histological UIP (31%) than the remaining 1535.

§ Among the asbestos-exposed group, small numbers of asbestos bodies were found in histological specimens of 21 cases of histological UIP.

§ PPs and asbestos bodies were more frequent in the 239 patients with histological UIP than in the remaining 1479 UIP-negative patients.

§ CONCLUSION: § Asbestos exposure causes asbestosis and

increases the incidence of histological UIP

§ Asbestosis vs other forms of interstitial lung disease.

§ Asbestosis - Variable, with the pattern being peribronchial and perivascular in 100%.

§ Non-asbestosis - 71% showed interstitial fibrosis with a variable (usually modest) amount of admixed elastic tissue

§ IPF also showed fibroelastosis, but confined to regions of overt "honeycomb" change.

Asbestosis: demonstration of distinctive interstitial fibroelastosis: a pilot studynn Wick

MR et al Diagn Pathol. 2009;13:297-302.

UIP AND ASBESTOSIS

§ F-IIP: unexplained occurrence of diffuse parenchymal lung disease in related individuals, said to be indistinguishable from UIP/IPF.

§ 30 patients - consensus diagnosis was “unclassifiable” parenchymal fibrosis (60%), with a high incidence of histopathologic honeycombing, fibroblast foci, and smooth muscle in fibrosis.

§ UIP, strictly defined, was identified in less than half of the F-IIP cases (range, 23%-50%). Interobserveragreement was fair (κ  =  0.37).

§ Subjects with UIP had a shorter survival and younger age at death.

Familial idiopathic interstitial pneumonia: histopathology and survival in 30 patients. Leslie KO et al. Arch Pathol Lab Med. 2012;136:1366-76.

Drug reactions – May not be the systemic disease but its treatment that causes pulmonary pathology

• Very rarely is a histologic pattern specific for a drug reaction (eg amiodarone)

• May however be pointers

• 1. Eosinophilia

• 2. Cytologic atypia within epithelial cells

• 3. UIP pattern is rarewww.pneumotox.com

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Conclusion: Histologic pattern of UIP in non-IPF patients.

• Most are seen in the context of IPF but…• Chronic Hypersensitivity Pneumonia (HP)• Collagen Vascular Disease (RA, PM, SS)• Drug Toxicity (Usually cytotoxic drugs)• Asbestosis• Familial Idiopathic Pulmonary Fibrosis

If a pattern of UIP is made on histology, look for features that argue against a diagnosis of IPF and comment, if present…

Granulomas, bronchocentricity, areas of inflammation without fibrosis, areas of organising pneumonia, asbestosis bodies,

pathology in other anatomic compartments (pleura, vasculature, airways), prominent eosinophils

UIP pattern(all four criteria)

Probable UIP pattern Possible UIP pattern(all three criteria)

Not UIP pattern (Any of the six criteria)

• Evidence of marked fibrosis/ architectural distortion, +/-honeycombing in a predominantly subpleural/ paraseptal distribution

• Presence of patchy involvement of lung parenchyma by fibrosis

• Presence of fibroblast foci

• Absence of features against a diagnosis of UIP suggesting an alternate diagnosis(see fourth column)

• Evidence of marked fibrosis / architectural distortion, +/-honeycombing

• Absence of e ither patchy involvement orfibroblastic foci, but not both

• Absence of features against a diagnosis of UIP suggesting an alternate diagnosis(see fourth column)

• Patchy or diffuse involvement of lung parenchyma by fibrosis, with or without interstitial inflammation

• Absence of other criteria for UIP (see UIP pattern column)

• Absence of features against a diagnosis of UIP

• Hyaline membranes *

• O rganizing pneumonia *†

• Granulomas †• Marked

interstitial inflammatory cell infiltrate away from honeycombing

• Predominant airway centered changes

• O ther features suggestive of an alternate diagnosis

OR• Honeycomb

changes only**

ATS/ERS/JRS/ALAT Statement: Idiopathic Pulmonary Fibrosis: Evidence-based Guidelines for Diagnosis and Management.

Raghu G et al. Am J Respir Crit Care Med 2011;183:788-824.

HRCT Pattern *

Surgical Lung Biopsy Pattern *

(when performed)

Diagnosis of IPF? †

UIP

UIP

YESProbable UIP

Possible UIP

Non-classifiable fibrosis **

Not UIP No

c/w UIP

UIPYES

Probable UIP

Possible UIPProbable ††Non-classifiable

fibrosis

Not UIP No

Inconsistent with UIP

UIP Possible ††

Probable UIP

NoPossible UIP

Non-classifiable fibrosis

Not UIP

Non-specific InterstitialPneumonia (NSIP)

ATS/ERS consensus classification of idiopathic interstitial pneumonias

Am J Respir Crit Care Med 2002; 165: 266-301

HISTOLOGIC PATTERN CLINICOPATHOLOGIC DIAGNOSIS

Usual interstitial pneumonia Idiopathic Pulmonary Fibrosis

Non-specific interstitial pneumonia Non-specific interstitial pneumonia*

Respiratory Bronchiolitis (RB) RB- associated ILD (RB-ILD)

Desquamative interstitial pneumonia Desquamative interstitial pneumonia

Diffuse alveolar damage Acute interstitial pneumonia

Organising pneumonia Cryptogenic organising pneumonia

Lymphoid interstitial pneumonia Lymphoid interstitial pneumonia

ATS/ERS consensus classification of idiopathic interstitial pneumonias

Am J Respir Crit Care Med 2013; 188: 733-748

HISTOLOGIC PATTERN CLINICOPATHOLOGIC DIAGNOSIS

Usual interstitial pneumonia Idiopathic Pulmonary Fibrosis

Non-specific interstitial pneumonia Non-specific interstitial pneumonia

Respiratory Bronchiolitis (RB) RB- associated ILD (RB-ILD)

Desquamative interstitial pneumonia Desquamative interstitial pneumonia

Diffuse alveolar damage Acute interstitial pneumonia

Organising pneumonia Cryptogenic organising pneumonia

Lymphoid interstitial pneumonia Lymphoid interstitial pneumonia

ATS/ERS subdivision of NSIPCellular Fibrotic

• ATS/ERS workshop – AJRCCM 2008;177:1338-47• Sixty-seven cases (out of 305)• Mean age was 52 years, 67% were women, 69% were never

smokers,• Dyspnea (96%) and cough (87%); 69%had restriction.• HRCT - lower lung predominant, reticular pattern (87%) with• traction bronchiectasis (82%) and volume loss (77%). • Five-year survival was 82.3%.

• Distinct clinical entity that occurs mostly in middle-aged women who are never-smokers. The prognosis of NSIP is very good.

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OP and cellular NSIP

Consolidation etc.

NSIP versus DIPSmoking-related interstitial lung disease

• 58, male• Two years of exertional dyspnoea • No obvious steroid effect • on disease course• Bilateral basal crackles, not clubbed • Life-long non-smoker• No CTD symptoms• No occupational exposures• BAL: normal differential• Restrictive PFT. FVC 61%, • DLco 57%

UIP, consistent with IPF

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Histopathology: F-NSIP

• MDT review: • HRCT favours chr HP• History of bird exposure

• Levels cut on block…

ØFINAL DIAGNOSIS:Ø CHR HP

ATS/ERS workshop – “relatively few at the centre of the circle”

• SOME PATIENTS WITH IDIOPATHIC NSIP SUBSEQUENTLY DEVELOP COLLAGEN VASCULAR DISEASES

• Kono M et al. Nonspecific interstitial pneumonia preceding diagnosis of collagen vascular disease. RespirMed. 2016 Aug;117:40-7.

• 17% developed CVD during the follow-up period (5.5 ± 5.0 years);• (DM = 3, DM/Sjogren's syndrome = 2, RA = 1)

• SUBDIVISION OF PATIENTS WITH A BIOPSY SHOWING NSIP PROVIDES PROGNOSTIC INFORMATION

• Kambouchner M. Non-specific interstitial pneumonia subdivision into pathological subgroups is clinically relevant from a prognostic and causal perspective. Histopathology. 2014 Oct;65(4):549-60. Nunes H Nonspecific interstitial pneumonia: survival is influenced by the underlying cause. Eur Respir J. 2015;45:746-55.

• Survival was better for UCTD than for idiopathic NSIP. • cHP survival tended to be poorer than that of idiopathic NSIP (p=0.087) and was

an independent predictor of mortality

• INTERSTITIAL PNEUMONIA WITH AUTOIMMUNE FEATURES (IPAF) - ? A NEW ENTITY

• Fischer A et al. An official European Respiratory Society/American Thoracic Society research statement: interstitial pneumonia with autoimmune features.-NSIP. Eur Respir J. 2015 Oct;46(4):976-87.

• …a morphologic domain consisting of specific chest imaging, histopathologic (NSIP/OP/LIP) or pulmonary physiologic features.

• A designation of IPAF should be used to identify individuals with IIP and features suggestive of, but not definitive for, a CTD.

Update on NSIP…

RA SLE SSc PM/DM SjSAmyloid

B’litis

UIP ++? +/- + + +/-

NSIP ++? +? +++ ++ ++

LIP/FB ++ +/- - - ++

OP + +/- +/- ++ +/-

DAD + ++ +/- +/- -

DIP/RB +/-* - +* - -

The prevalence of interstitial pneumoniasin patients with connective tissue diseases

The same spectrum of patterns exists in CTDs as for idiopathic disease• However…• The prevalence differs overall (NSIP common)• The prevalence of IP patterns differs for each CTD• Treatment and prognoses differ from idiopathic disease

RA SLE SSc PM/DM SjSAmyloid

B’litis

UIP ++? +/- + + +/-

NSIP ++? +? +++ ++ ++

LIP/FB ++ +/- - - ++

OP + +/- +/- ++ +/-

DAD + ++ +/- +/- -

DIP/RB +/-* - +* - -

The prevalence of interstitial pneumoniasin patients with connective tissue diseases

The same spectrum of patterns exists in CTDs as for idiopathic disease• However…• The prevalence differs overall (NSIP common)• The prevalence of IP patterns differs for each CTD• Treatment and prognoses differ from idiopathic disease

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AIP

sarcoid NSIPLAM

DIP

RB-ILD

Langerhanscell

histiocytosis

OP

HP

LIP

Idiopathicpulmonary

haemorrhage

UIP

Disease overlap in Interstitial Lung Disease

Sameness…. Coexistence… Transformation….

AIP

sarcoid NSIPLAM

DIP

RB-ILD

Langerhanscell

histiocytosis

OP

HP

LIP

Idiopathicpulmonary

haemorrhage

UIP

Disease overlap in Interstitial Lung Disease

Sameness…. Coexistence…, Transformation…..

2000 20052003

Other anatomic compartments…Patient with SLE

Diffuse lung disease in infancy and childhood: expanding the chILDclassification (0-2 years/2-18 years/mimics of ILD).

Rice A et al. Histopathology. 2013;63:743-55.

Deutsch G et al. AJRCCM 2007:176:1120-8

Diffuse Lung Disease in Biopsied Children 2 to 18 Years of Age. Application of the chILD

Classification Scheme.

Fan LL et al. Ann Am Thorac Soc. 2015;12:1498-505

2 year old female

Increasing shortness of breath, ?ILD

c.218T>C in the SFTPC gene

Fibrotic NSIP

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Surfactant protein dIisorders

12 month old femaleBorn three weeks prematurely (birth weight 3.5kg) with

severe hyaline membrane disease that required ventilation for 10 days.

Has since had recurrent respiratory tract infections

2003 2013

Non-specific interstitial pneumonia in children

• PROS OF CRYOBIOPSY

• Surgical lung biopsy has a higher diagnostic yield than tranbronchial biopsy - 0.81 (0.75 – 0.87) vs 34% (1,2) Similar complication rate (2).

• Cryobiopsy has lower complication rates and mortality rates compared to SLB (1).

• Bronchoscopic cryobiopsy has a meaningful impact on diagnostic confidence in MDTs for ILDs, and may prove useful in the diagnosis of IPF. (3)

• Coste efficiency – “The systematic use of cryobiopsysaved up to €59,846 (over 3 years)” (4): £210 per patient in the first year and £647 in subsequent years (5).

• CONS OF CRYOBIOPSY

• Surgical lung biopsy has a higher diagnostic yield than cryobiopsy (0.987 vs 0.81 (0.75 –0.87)) (1)

• In one series for cryobiopsy, severe bleeding was reported as 53% (6)

• Lack of studies showing direct comparison of the two techniques (7,8)

• Not available routinely

1. Rav aglia C et al. Saf ety and Diagnostic Y ield of Transbronchial Lung Cry obiopsy in Dif f use Parenchy mal Lung Diseases: A Comparativ e Study v ersus Video-Assisted Thoracoscopic Lung Biopsy and a Sy stematic Rev iew of the Literature. Respiration. 2016;91(3):215-27

2. Pajares V et al. Diagnostic y ield of transbronchial cry obiopsy in interstitial lung disease: a randomized trial. Respirology . 2014 Aug;19(6):900-63. Tomassetti S et al. Bronchoscopic Lung Cry obiopsy Increases Diagnostic Conf idence in the Multidisciplinary Diagnosis of Idiopathic Pulmonary Fibrosis. Am J Respir Crit Care Med. 2015 193:745-524. Hernández-González F et al. Cry obiopsy in the diagnosis of dif f use interstitial lung disease: y ield and cost-ef f ectiveness analy sis. Arch Bronconeumol. 2015;51:261-75. Sharp C et al. Use of transbronchial cry obiopsy in the diagnosis of interstitial lung disease-a sy stematic rev iew and cost analy sis. QJM. 2016 [Epub ahead of print]6. Hagmey er L, et al.The role of transbronchial cry obiopsy and surgical lung biopsy in the diagnostic algorithm of interstitial lung disease. Clin Respir J. 20157. Johannson KA y et al. Diagnostic Y ield and Complications of Transbronchial Lung Cry obiopsy f or Interstitial Lung Disease: A Sy stematic Rev iew and Meta-analy sis. Ann Am Thorac Soc. 2016;188-18388. Raparia K et al. Transbronchial Lung Cry obiopsy f or Interstitial Lung Disease Diagnosis: A Perspectiv e From Members of the Pulmonary Pathology Society Arch Pathol Lab Med. 2016 Jul. [Epub ahead of

print]

USAGE OF CRYOBIOPSIES

• Johannson KA yet al. Diagnostic Yield and Complications of Transbronchial Lung Cryobiopsy for Interstitial Lung Disease: A Systematic Review and Meta-analysis. Ann Am Thorac Soc. 2016 Jul. [Epub ahead of print]

• Raparia K et al. Transbronchial Lung Cryobiopsy for Interstitial Lung Disease Diagnosis: A Perspective From Members of the Pulmonary Pathology Society Arch Pathol Lab Med. 2016 Jul. [Epub ahead of print]

• The diagnostic accuracy of transbronchial lung cryobiopsycannot be determined given the absence of studies directly comparing cryobiopsydiagnoses to diagnoses derived from with surgical lung biopsies interpreted within multidisciplinary discussions.

• The histopathological and multidisciplinary discussion-based diagnostic yield of transbronchial cryobiopsyappear high, but with variable frequencies of complications dominated by pneumothorax and moderate to severe hemorrhage.

• Hagmeyer L et al. Validation of transbronchial cryobiopsy in interstitial lung disease - interim analysis of a prospective trial and critical review of the literature. Sarcoidosis Vasc Diffuse Lung Dis. 2016;33:2-9.

• In 75% of cases, SLBx deemed unnecessary after Cry-bx. • In 12/13 subjects, an SLB was performed confirming Cryo-TBB results in 92%.

Rate of NSIP in cryobiopsies….• BIOPSY TYPE CBC SLB• Hagmeyer et al 19%• Ravaglia et al 8% vs 15%• Tomassetti et al 7% vs 5%

Bronchoscopic cryobiopsy in NSIP diagnosis

• 57 year old female never smoker. • History of Farmer’s Lung 20 years previously

treated with steroids.• Arthritis for 10 years (autoimmune screen

negative). • On Omeprazole and Fesoterodine.• CT - Patchy ground-glass changes in mid and

upper zones.• BAL - Eosinophilia (17%) and mild neutrophilia

(6%). No lymphocytosis (8%). • Lung function tests: Moderate restrictive defect,

in keeping with the known interstitial lung disease.

MDT REVIEW: Probable F-NSIP. No serological evidence of connective tissue disease but could be associated given 10 year history of arthritis. Possibility of a drug reaction also considered.

F- NSIP – Idiopathic currently, ? secondary to CTD or drug reaction

Treated with immunosuppression and stable at 3 months

Histopathology (cryobiopsy): The features favour fibrotic non-specific interstitial pneumonia (NSIP), possibly secondary to progression of organising pneumonia

USAGE OF CRYOBIOPSIES IN THE DIAGNOSIS OF NSIP

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NSIP and overlapping histology on cryobiopsy

UPPER

LOBE

LOWER

LOBE

UIP ON CRYOBIOPSY

UIP is the prognostic indicator

K. R. Flaherty et al Histopathologic variability in usual and nonspecific interstitial pneumonias. Am J Respir Crit Care Med

164 (9):1722-1727, 2001.

Monaghan H et al. Prognostic implications of histologic patterns in multiple surgical lung biopsies from patients with

idiopathic interstitial pneumonias. Chest. 2004 Feb;125(2):522-6.

Lower lobe: UIP Middle lobe: NSIP

SIZE AND NUMBER OF BIOPSY SITES AND NUMBER OF BIOPSIES

Clin-Rad- Pathologic Diagnosis• Idiopathic Pulmonary Fibrosis• Idiopathic Nonspecific Interstitial Pneumonia• Respiratory Bronchiolitis• Interstitial Lung Disease• Desquamative Interstitial Pneumonia• Cryptogenic Organizing Pneumonia• Acute Interstitial Pneumonia

• ATS/ERS IIP Classification Revision: Updates existing entities• NSIP accepted and defined

• NSIP “subtypes” - 1ary and 2ary have clinical and prognostic relevance.

• IPAF should be considered as another entity with an NSIP pattern

• NSIP in children should warrant investigation for Surfactant Protein Gene Mutations.

Rare IIPs• Idiopathic Lymphoid interstitial pneumonia• Idiopathic Pleuroparenchymal Fibrolastosis

Rare histologic patterns• Acute fibrinous and organising pneumonia• Bronchiolocentric patterns of IP

Unclassifiable IIP

ATS/ERS Revised 2013 Classification

UIP, NSIP and their differential diagnoses

• NSIP and UIP can be diagnosed on cryobiopsybut need identical MDT review as for SLBx, possibly even more important.

• Revisions of guidelines in 2018…..

• UIP - most are seen in the context of IPF but…

• Chronic Hypersensitivity Pneumonitis (EAA)• Collagen Vascular Disease (RA, PM, SS)• Asbestosis• Familial Idiopathic Pulmonary Fibrosis• Drug Toxicity (Usually cytotoxic drugs)