Answer and References

Answer: A

A.      A ratio of FVC/DLCO percent predicted >1.6 suggests PH. 


Continue Reading

DLCO <65% predicted in the absence of significant lung volume abnormalities or ≥20% decrease in DLCO over the course of a year suggests PH, particularly in a patient with longstanding limited cutaneous SSc. The FVC/DLCO ratio is another way to assess whether the degree of impairment of gas transfer is greater than what would be expected on the basis of ILD.

B.      FVC and/or total lung capacity <80% predicted with reduced DLCO is indicative of a restrictive pattern, consistent with ILD. ILD and PH may occur simultaneously, but this pattern on pulmonary function testing alone is not highly suggestive of PH.

C.      Plasma levels of BNP and/or NT-proBNP are useful screening tools for PH.  In one study, elevated NT-proBNP levels in patients with SSc patients had a sensitivity and specificity of 90% for the presence of pulmonary arterial hypertension. 

References

Allanore Y, Borderie D, Meune C, et al. N-terminal pro-brain natriuretic peptide as a diagnostic marker of early pulmonary artery hypertension in patients with systemic sclerosis and effects of calcium-channel blockers. Arthritis Rheum. 2003;48:3503-3508.

Bradley B, Branley HM, Egan JJ, et al. Interstitial lung disease guideline: the British Thoracic Society in collaboration with the Thoracic Society of Australia and New Zealand and the Irish Thoracic Society. Thorax. 2008;63 Suppl 5:v1-v58.

Fischer A, Swigris JJ, Groshong SD, et al. Clinically significant interstitial lung disease in limited scleroderma: histopathology, clinical features, and survival. Chest. 2008;134:601-605.

Gilson M, Zerkak D, Wipff J, et al. Prognostic factors for lung function in systemic sclerosis: prospective study of 105 cases. Eur Respir J. 2010;35:112-117.

Gladue H, Steen V, Allanore Y, et al. Combination of echocardiographic and pulmonary function test measures improves sensitivity for diagnosis of systemic sclerosis-associated pulmonary arterial hypertension: analysis of 2 cohorts. J Rheumatol. 2013;40:1706-1711.

Günther S, Jaïs X, Maitre S, et al. Computed tomography findings of pulmonary venoocclusive disease in scleroderma patients presenting with precapillary pulmonary hypertension. Arthritis Rheum. 2012;64:2995-3005.

Hoeper MM, Bogaard HJ, Condliffe R, et al. Definitions and diagnosis of pulmonary hypertension. J Am Coll Cardiol. 2013;62:D42-D50.

Khanna D, Gladue H, Channick R, et al. Recommendations for screening and detection of connective tissue disease-associated pulmonary arterial hypertension. Arthritis Rheum. 2013;65:3194-201.

Latsi PI, du Bois RM, Nicholson AG, et al. Fibrotic idiopathic interstitial pneumonia: the prognostic value of longitudinal functional trends. Am J Respir Crit Care Med. 2003;168:531-537.

Steen VD, Lucas M, Fertig N, Medsger TA Jr. Pulmonary arterial hypertension and severe pulmonary fibrosis in systemic sclerosis patients with a nucleolar antibody. J Rheumatol. 2007;34:2230-2235.