I.a I - Interstitial/parenchymal lung disease
I.a - Pneumonitis (ILD), acute and/or severe (may cause ARDS) I.b I - Interstitial/parenchymal lung disease
I.b - Pneumonitis (ILD) I.d I - Interstitial/parenchymal lung disease
I.d - Organizing pneumonia pattern (an area or areas of consolidation on imaging) II.b II - Pulmonary edema - Acute lung injury - ARDS
II.b - ARDS - Acute lung injury III.a III - Pulmonary/alveolar./airway hemorrhage/bleeding
III.a - Alveolar hemorrhage (AH), diffuse AH (DAH) III.b III - Pulmonary/alveolar./airway hemorrhage/bleeding
III.b - Pneumorenal syndrome (w/wo ANCAs) III.d III - Pulmonary/alveolar./airway hemorrhage/bleeding
III.d - Alveolar hemorrhage, diffuse (ANCA-positive/-related) IV.a IV - Airway involvement
IV.a - Bronchospasm - Wheezing - Asthma V.d V - Pleural and/or pericardial involvement
V.d - Pleural/pericardial effusion, ANA positive (DI lupus) V.i V - Pleural and/or pericardial involvement
V.i - Pleuritis (can cause chest pain) V.m V - Pleural and/or pericardial involvement
V.m - Pleuropericarditis - Pleuropericardial effusion (ANA unknown or negative) VI.d VI - Pulmonary vasculopathies
VI.d - Pulmonary vasculitis or capillaritis VIII.a VIII - Central-large-upper airway (incl. pharyngeal-nasal) involvement
VIII.a - Angioedema (may cause UAO, asphyxia and death) VIII.c VIII - Central-large-upper airway (incl. pharyngeal-nasal) involvement
VIII.c - Upper airway obstruction other than angioedema or hematoma VIII.h VIII - Central-large-upper airway (incl. pharyngeal-nasal) involvement
VIII.h - Vocal cord dysfunction, adduction, closure, injury X.a X - Systemic/Distant conditions, syndromes and reactions
X.a - DRES syndrome - DRESS-like reaction X.b X - Systemic/Distant conditions, syndromes and reactions
X.b - Antiphospholipid antibodies w/wo the APL syndrome X.d X - Systemic/Distant conditions, syndromes and reactions
X.d - Lupus - Lupus syndrome (see also Vd) X.e X - Systemic/Distant conditions, syndromes and reactions
X.e - Autoimmunity-Autoimmune conditions (+ANA, +anti-ds-DNA, +ANCAs, other auto-Abs) X.m X - Systemic/Distant conditions, syndromes and reactions
X.m - Vascultis (pulmonary, extrathoracic or systemic)-ANCA status unknown or negative) X.o X - Systemic/Distant conditions, syndromes and reactions
X.o - Neutrophilic dermatosis (Pyoderma, Sweet syndrome) X.s X - Systemic/Distant conditions, syndromes and reactions
X.s - Vasculitis, pulmonary (w/wo AH), extrapulmonary, systemic: ANCA-positive X.ak X - Systemic/Distant conditions, syndromes and reactions
X.ak - Dual MPO-/PR3-ANCA systemic disease/vasculitis/pseudovasculitis XII.c XII - Cardiovascular involvement / toxicity
XII.c - Pericardial effusion (w/wo tamponade) XII.k XII - Cardiovascular involvement / toxicity
XII.k - Constrictive pericarditis - Pericardial thickening XV.f XV - Pathology
XV.f - Path: Diffuse alveolar damage (DAD-pattern) (see also IL)

III.a III - Pulmonary/alveolar./airway hemorrhage/bleeding
III.a - Alveolar hemorrhage (AH), diffuse AH (DAH) III.d III - Pulmonary/alveolar./airway hemorrhage/bleeding
III.d - Alveolar hemorrhage, diffuse (ANCA-positive/-related) VI.b VI - Pulmonary vasculopathies
VI.b - Pulmonary arterial hypertension IX.t IX - Neuromuscular / CNS involvement - Disordered breathing during sleep
IX.t - CNS involvement/dysfunction/damage X.b X - Systemic/Distant conditions, syndromes and reactions
X.b - Antiphospholipid antibodies w/wo the APL syndrome X.j X - Systemic/Distant conditions, syndromes and reactions
X.j - Myopathy-Myositis-Polymyositis (see also under Xba) X.m X - Systemic/Distant conditions, syndromes and reactions
X.m - Vascultis (pulmonary, extrathoracic or systemic)-ANCA status unknown or negative) X.s X - Systemic/Distant conditions, syndromes and reactions
X.s - Vasculitis, pulmonary (w/wo AH), extrapulmonary, systemic: ANCA-positive X.ad X - Systemic/Distant conditions, syndromes and reactions
X.ad - Skin purpura, ecchymoses or necrosis X.ak X - Systemic/Distant conditions, syndromes and reactions
X.ak - Dual MPO-/PR3-ANCA systemic disease/vasculitis/pseudovasculitis XI.n XI - Miscellaneous
XI.n - Neutropenia, agranulocytosis (w/wo infection/sepsis) XII.g XII - Cardiovascular involvement / toxicity
XII.g - Coronary artery disease (acute) - Myocardial ischemia/infarction XV.al XV - Pathology
XV.al - Path: Pulmonary hypertension incl. angiomatoid vasculopathy XV.aw XV - Pathology
XV.aw - Path: Skin vasculopathy/vasculitis/fibrin thrombi XVIII.t XVIII - Distinctive patterns - 'Eye-catchers'
XVIII.t - Eye catcher: Purpuric/Ecchymotic/Cyanotic lesions of the earlobes and/or nose

III.a III - Pulmonary/alveolar./airway hemorrhage/bleeding
III.a - Alveolar hemorrhage (AH), diffuse AH (DAH) III.b III - Pulmonary/alveolar./airway hemorrhage/bleeding
III.b - Pneumorenal syndrome (w/wo ANCAs) III.c III - Pulmonary/alveolar./airway hemorrhage/bleeding
III.c - Hemoptysis V.a V - Pleural and/or pericardial involvement
V.a - Pleural effusion (uni- or bilateral) (can accompany DI-LDs) V.m V - Pleural and/or pericardial involvement
V.m - Pleuropericarditis - Pleuropericardial effusion (ANA unknown or negative) VI.b VI - Pulmonary vasculopathies
VI.b - Pulmonary arterial hypertension VI.d VI - Pulmonary vasculopathies
VI.d - Pulmonary vasculitis or capillaritis VIII.i VIII - Central-large-upper airway (incl. pharyngeal-nasal) involvement
VIII.i - Midline destructive lesions VIII.o VIII - Central-large-upper airway (incl. pharyngeal-nasal) involvement
VIII.o - Perforation of the nasal septum VIII.ai VIII - Central-large-upper airway (incl. pharyngeal-nasal) involvement
VIII.ai - Nasal, palatal and/or pharyngeal pathology IX.t IX - Neuromuscular / CNS involvement - Disordered breathing during sleep
IX.t - CNS involvement/dysfunction/damage X.j X - Systemic/Distant conditions, syndromes and reactions
X.j - Myopathy-Myositis-Polymyositis (see also under Xba) X.o X - Systemic/Distant conditions, syndromes and reactions
X.o - Neutrophilic dermatosis (Pyoderma, Sweet syndrome) X.s X - Systemic/Distant conditions, syndromes and reactions
X.s - Vasculitis, pulmonary (w/wo AH), extrapulmonary, systemic: ANCA-positive X.ad X - Systemic/Distant conditions, syndromes and reactions
X.ad - Skin purpura, ecchymoses or necrosis X.ak X - Systemic/Distant conditions, syndromes and reactions
X.ak - Dual MPO-/PR3-ANCA systemic disease/vasculitis/pseudovasculitis XI.n XI - Miscellaneous
XI.n - Neutropenia, agranulocytosis (w/wo infection/sepsis) XI.r XI - Miscellaneous
XI.r - Death following exposure or poisoning XII.g XII - Cardiovascular involvement / toxicity
XII.g - Coronary artery disease (acute) - Myocardial ischemia/infarction XII.aa XII - Cardiovascular involvement / toxicity
XII.aa - Arterial (aorta, limb) vasoconstriction and/or ischemia, acute XV.al XV - Pathology
XV.al - Path: Pulmonary hypertension incl. angiomatoid vasculopathy XV.aw XV - Pathology
XV.aw - Path: Skin vasculopathy/vasculitis/fibrin thrombi XVI.b XVI - Imaging
XVI.b - Imaging: Ground-glass opacities (GGO) / shadowing XVIII.t XVIII - Distinctive patterns - 'Eye-catchers'
XVIII.t - Eye catcher: Purpuric/Ecchymotic/Cyanotic lesions of the earlobes and/or nose

I.b I - Interstitial/parenchymal lung disease
I.b - Pneumonitis (ILD) I.c I - Interstitial/parenchymal lung disease
I.c - Eosinophilic pneumonia (pulmonary infiltrates and eosinophilia) I.d I - Interstitial/parenchymal lung disease
I.d - Organizing pneumonia pattern (an area or areas of consolidation on imaging) I.k I - Interstitial/parenchymal lung disease
I.k - Lung nodule or nodules II.b II - Pulmonary edema - Acute lung injury - ARDS
II.b - ARDS - Acute lung injury III.a III - Pulmonary/alveolar./airway hemorrhage/bleeding
III.a - Alveolar hemorrhage (AH), diffuse AH (DAH) III.b III - Pulmonary/alveolar./airway hemorrhage/bleeding
III.b - Pneumorenal syndrome (w/wo ANCAs) III.d III - Pulmonary/alveolar./airway hemorrhage/bleeding
III.d - Alveolar hemorrhage, diffuse (ANCA-positive/-related) IV.a IV - Airway involvement
IV.a - Bronchospasm - Wheezing - Asthma IV.r IV - Airway involvement
IV.r - Airway pigmentation (black, bluish, petechial) V.b V - Pleural and/or pericardial involvement
V.b - Eosinophilic pleural effusion V.d V - Pleural and/or pericardial involvement
V.d - Pleural/pericardial effusion, ANA positive (DI lupus) V.m V - Pleural and/or pericardial involvement
V.m - Pleuropericarditis - Pleuropericardial effusion (ANA unknown or negative) V.u V - Pleural and/or pericardial involvement
V.u - Eosinophilic pleuritis VI.d VI - Pulmonary vasculopathies
VI.d - Pulmonary vasculitis or capillaritis X.d X - Systemic/Distant conditions, syndromes and reactions
X.d - Lupus - Lupus syndrome (see also Vd) X.e X - Systemic/Distant conditions, syndromes and reactions
X.e - Autoimmunity-Autoimmune conditions (+ANA, +anti-ds-DNA, +ANCAs, other auto-Abs) X.m X - Systemic/Distant conditions, syndromes and reactions
X.m - Vascultis (pulmonary, extrathoracic or systemic)-ANCA status unknown or negative) X.s X - Systemic/Distant conditions, syndromes and reactions
X.s - Vasculitis, pulmonary (w/wo AH), extrapulmonary, systemic: ANCA-positive X.x X - Systemic/Distant conditions, syndromes and reactions
X.x - Subclinical ANCA positivity X.ak X - Systemic/Distant conditions, syndromes and reactions
X.ak - Dual MPO-/PR3-ANCA systemic disease/vasculitis/pseudovasculitis XI.n XI - Miscellaneous
XI.n - Neutropenia, agranulocytosis (w/wo infection/sepsis) XV.a XV - Pathology
XV.a - Path: NSIP-cellular pattern (see also Ia, Ib) XV.c XV - Pathology
XV.c - Path: Organizing pneumonia (OP/BOOP) pattern (see also Id) XV.h XV - Pathology
XV.h - Path: NSIP-fibrotic pattern XV.an XV - Pathology
XV.an - Path: Eosinophilic pleuritis