51-year-old male, with no significant personal history, non-smoker, no known allergies, no occupational exposures, no history of traveling six months prior to consultation, and no pet owner. He consulted with two-week asthenia, adynamia, malaise, rhinorrhea, and dyspnea (modified Medical Research Council) mMRC1, that worsened with exposure to air conditioning. Additionally, he presented with xerostomia and weight loss of 3 kg in 3 months. Physical examination showed normal vital signs, oropharynx erythema without lesions of the oral mucosa, no neck masses nor jugular engorgement, crackles at the end of inspiration in lung bases at auscultation. The rest of the physical examination was unremarkable.
Chest radiograph showed basal reticular opacities, without consolidation areas. Chest CT-scan showed thickening of inter and intralobular septa, grounded glass areas predominantly in the bases with multiple consolidation areas (Fig. 1). Blood count showed leukocytosis and neutrophilia, hemoglobin of 14 g/dL, C-reactive protein of 5, normal lactate dehydrogenase (LDH), creatinine and liver tests. Sputum bacilloscopic (BK) was negative. With these findings, multilobes community acquired pneumonia was suspected, IV antibiotics were initiated, with gradual improvement, until the patient was finally discharged.
One month after discharge, he consulted at the outpatient clinic due to persistent cough and worsening of dyspnea (mMRC2). Chest radiograph showed persistence of bilateral basal interstitial infiltrates, severe DLCO decrease up to 29% of predicted, non-interpretable spirometry due to non-toleration of the procedure. ANAs were found in 1:320 (speckled pattern), positive ENAs Anti Ro/SSA of 100 U/mL, Anti La/SSA of 60 U/mL, Anti-Smith (Sm) of 2.4 U/mL, Anti RNP (antinuclear ribonucleoprotein antibodies) of 2.3 U/mL (Table 1). Physical examination revealed persistence of crackles at the end of inspiration, predominantly in the bases, with adequate oxygen saturation at rest. These findings were considered secondary to an interstitial lung disease. He was admitted for a rheumatology assessment with the suspicion of pulmonary affection as the presenting feature of SS, with a European League Against Rheumatism-Sjogren's Syndrome (EULAR-SS) disease activity index (ESSDAI) score at diagnosis of 15 points.
Upon admission blood workup was completed finding a normal blood, negative c-reactive protein, normal complement, negative anti cardiolipin synthase (anti-CLS), negative anti deoxyribonucleic acid (anti-DNA), negative antineutrophil cytoplasmic antibodies (ANCAs), positive ANAs, ENAs, Anti Ro and Anti La (Table 1). Bronchoscopy with transbronchial biopsies was performed along with bronchoalveolar lavage (Fig. 2). Direct microscopic examination and cultures for bacteria, fungi and mycobacteria and Gen-Expert for tuberculosis were all negative. Histological sections showed pulmonary parenchyma with altered architecture given by the presence of collagen foci and young fibroblasts that in some places protrude towards the alveolar spaces. In some alveolar septa there is lymphoplasmacytic cellularity without acute inflammation. This was considered compatible with organizing pneumonia (Fig. 3).
Treatment with methylprednisolone pulses was initiated for three days along with intravenous cyclophosphamide 500 mg/m2. Improvement of symptoms such as cough and dyspnea were seen, as well as of the basal crackles. Given the clinical improvement, the patient was discharged with oral steroids and cyclophosphamide with outpatient control with pulmonology and rheumatology. Although Schirmer's test was not performed, a salivary gland biopsy was done without histological alterations. The patient fulfilled 3 points of the EULAR criteria with positive anti-SSA. Despite the above, the patient still considered to have primary SS, since all etiologies of secondary SS were ruled out.
High-resolution chest CT-scan showing thickening of inter and intralobular septa associated with grounded glass opacities predominantly in lung bases. Multiple foci of multilobes consolidation areas, bronchiolectasias without evidence of honeycomb, suggestive of unspecified interstitial pneumonia.