Epidemiology
- Incidence of Primary Sjogren’s Syndrome: 0.5-3%
- Genetics
- Familial clustering has been reported
- Associated with HLA-Dw2 and HLA-Dw3
Etiologic Classification
- Primary Sjogren’s Syndrome (34-50% of cases, not associated with connective tissue disease): occurs predominantly in post-menopausal females >40 y/o
- Secondary Sjogren’s Syndrome (50-66% of cases, associated with connective tissue disease):
- Rheumatoid Artritis (see [[Rheumatoid Arthritis]]): 15-20% of RA cases have associated Sjogren’s syndrome
- SLE (see [[SLE]])
- Polyarteritis Nodosa (see [[Polyarteritis Nodosa]])
- Scleroderma (see [[Scleroderma]])
- Mixed Connective Tissue Disease (see [[Mixed Connective Tissue Disease]])
- Polydermatomyositis (see [[Polydermatomyositis]])
Physiology
- Sjogren’s-Associated Vasculitis: hypersensitivity vasculitis (mostly involving the post-capillary venules within superficial dermis) with leukocytoclasis
- Probably due to immune complex deposition
- Autoimmune Exocrinopathy: lymphocytic infiltration of glandular (lacrimal, salivary, conjunctival, pharyngeal mucosal) and extraglandular organs
Diagnosis
- Rheumatoid factor (RF): positive in 75-90% of cases
- ANA: positive in 50-80% of cases
- Anti-SS-A (Ro)(directed against RNA transcription factors): positive in 40-50% of primary cases
- Anti-SS-B (La)(directed against RNA transcription factors): positive in 50% of cases
- Lip Bopsy: diagnostic
- Salivary Flow: reduced
Clinical Manifestations
Pulmonary Manifestations
(occur in 25% of cases -> however, it is often difficult to exclude the underlying connective tissue disease as the cause of lung findings in secondary Sjogren’s cases)
Interstitial Lung Disease (see [[ILD-Etiology]])
- Epidemiology
- Occurs in 10% of primary Sjogren’s cases
- Occurs more often in patients with extraglandular manifestations than in those with glandular disease alone
- Diagnosis
- CXR/Chest CT Patterns
- Fine Reticular or Reticulonodular Infiltrates: most common pattern
- Normal CXR: in some cases
- Pleural Effusion: may occur
- Nodular Infiltrates: pattern seen in cases with pseudolymphoma (aka Nodular Lymphoid Hyperplasia), lymphoma, or amyloidosis
- PFT’s: restriction (although minor degrees of obstruction also occur in a large proportion of cases)
- DLCO: decreased
- FOB-BAL: alveolitis with increased number of cells (predominantly lymphocytes)
- Primary Sjogren’s: 50% of patients without clinical lung disease have abnormal BAL cell counts (2 subsets of patients were identified: 69% had a lymphocyte-predominant pattern with >18% lymphocytes and 25% had a mixed neutrophil and lymphocyte pattern with >4% neutrophils)
- Patients with abnormal BAL cell counts had more severe Sjogren’s with extensive extraglandular disease (myositis, lymphadenopathy, renal , hepatic disease), higher serum IgG, higher serum ß2-microglobulin, higher prevalence of RF and ANA
- Secondary Sjogren’s (associated with either biliary cirrhosis or con-nective tissue disease): non-smokers without clinical lung disease have increased BAL lymphocytes (patients with a neutrophilic alveolitis had a marked increase in T8 cells in BAL)
- Primary cases also have activated alveolar macrophages (increased release of superoxide anion, etc.)
- OLB Patterns
- Nonspecific Interstitial Pneumonitis: most common pattern
- CXR/Chest CT Patterns
- Clinical
- Some cases are asymptomatic but most present with cough, dyspnea, and bibasilar crackles
- Extensive or progressive pulmonary fibrosis is rare (although around 7/30 cases in one 10-year study had significant decreases in DLCO)
Lymphocytic Interstitial Infiltration of Lung
- Epidemiology: all of these reside on a spectrum of lymphoproliferative disorders of the lung
- Pseudolymphoma (aka Nodular Lymphoid Hyperplasia)
- Frequently reported
- Diffuse or focal nodular lymphocytic infiltration with formation of lymphoid follicles
- Some cases have lymphadenopathy or salivary gland enlargement
- Tends to occur in cases with Sicca syndrome alone (and regresses with Corticosteroids + Cytoxan)
- May rarely evolve into frank lymphoma
- Lymphocytic Interstitial Pneumonia (see [[Lymphocytic Interstitial Pneumonia]])
- Most common form of diffuse lung disease in Sjogren’s syndrome
- Diffuse lymphocytic infiltration (with or without histiocytes and multinucleated giant cells), predominantly around bronchioles
- Primary Pulmonary Lymphoma (see [[Primary Pulmonary Lymphoma]])
- aka Mucosa-Associated Lymphoid Tissue (MALT)-Associated Lymphoma
- The prevalence of lymphoma is increased 40-50-fold in Sjogren’s
- Variable clinical presentation: ranges from diffuse interstitial infiltrates to nodular masses (often peri-hilar in location)
- Nodular pattern is the most common type
- May regress spontaneously and responds to steroids
Cryptogenic Organizing Pneumonia (see [[Cryptogenic Organizing Pneumonia]])
- Occurs less commonly in Sjogren’s syndrome than in RA or polydermatomyositis
- Usually responds to corticosteroids
Dessication of Tracheobronchial Tree
- Dried nasal passages (50% of cases/altered smell, epistaxis, septal perforation)
- Atrophic rhinitis
- Xerostomia (altered taste/Eustachian tube obstruction with otitis media)
- Xerotrachea (25% of cases: chronic dry cough with bronchoscopic evidence of inflammed bronchial mucosa
- Chronic bronchitis (cough with tenacious sputum)
- Atelectasis
- Middle lobe syndrome
- Recurrent bronchopneumonia (due to secretions)
Amyloidosis (see [[Amyloidosis]])
- May produce nodular infiltrates
Pulmonary Vasculitis
- Epidemiology: rare
- Vasculitis is usually confined to skin (palpable purpura predominantly of LE, nodules, ulcers) but may progress to polyarteritis nodosa-like syndrome
Pulmonary Hypertension (see Pulmonary Hypertension, [[Pulmonary Hypertension]])
- Epidemiology: uncommon
Pleural Disease (see [[Pleural Effusion-Exudate]])
- Epidemiology
- Reported in cases with associated connective tissue disease and associated with atelectasis or recurrent pneumonia
- Clinical
- Pleurisy
- Pleural Thickening
- Pleural Effusion: exudative
Obstructive Airways Disease (see [[Obstructive Lung Disease]])
- Physiology: due to mononuclear cell infiltration around small airways
- 40-60% of primary/secondary Sjogren’s cases have bronchial hyperresponsiveness
- PFT’s: high prevalence of small airways dysfunction
- May increase risk of bronchopeumonia
- Progression to severe BO is rare (unless due to associated RA)
Follicular Bronchiolitis (see [[Follicular Bronchiolitis]])
- Epidemiology
- May be more common in secondary Sjogren’s syndrome
- Diagnosis
- PFT’s: obstruction
- FOB: BAL lymphocytosis
- Chest CT:
- Centrilobular Nodules with Peripheral Tree-In-Bud Pattern: characteristic of bronchiolar disease
- Ground-Glass Opacities:
- Mediastinal Adenopathy: also seen in LIP and Nodular Lymphoid Hyperplasia
Rheum Manifestations
- xxx
Ocular Manifestations
- Keratoconjunctivitis Sicca Syndrome: triad of dry eyes (with or without lacrimal gland enlargement), xerostomia (with or without salivary gland enlargement), and presence of connective tissue disease (usually RA) may also occur
- Typically seen in females >40 y/o
- Positive Shirmer Test:
- Rose Bengal Score >3:
GI Manifestations
- xxx
Neuro Manifestations
- xxx
Prognosis
- BAL lymphocytosis predicts a relatively good prognosis
- Secondary Sjogren’s cases (with an associated connective tissue disease) with neutrophilic alveolitis by BAL have poorer outcome with clinical deterioration if untreated
Treatment
- Steroids/Cyclophosphamide: patients with ILD with LIP and BOOP histologies tend to respond better to these therapies
- Pseudolymphoma responds to these agents
References
- Launay D, Hachulla E, Hatron PY, Jaïs X, Simonneau G, Humbert M. Pulmonary arterial hypertension: a rare complication of primary Sjögren syndrome: report of 9 new cases and review of the literature. Medicine (Baltimore) 2007;86:299 –315