Interstitial lung fibrosis in some patients may be secondary to rheumatic diseases. When the following symptoms appear, prompt examination should be performed to exclude rheumatic diseases or to clarify the cause of interstitial lung fibrosis. 1, pain syndrome: joint, muscle, tendon pain is quite common, the large and small joints of the extremities can be involved, with symmetrical joint pain predominant. Morning stiffness and Raynaud’s phenomenon are important concomitant symptoms. 2. Skin manifestations: Most patients have skin changes, which are atopic or non-specific. There are various skin manifestations, such as urticaria, erythema annulare, erythema papulosum, erythema multiforme, erythema nodosum, erythema facialis, etc. 3. Eye manifestations: Eye symptoms may appear months or years before systemic symptoms. Symptoms include ocular dryness, increased intraocular pressure, cataract, orbital myelitis, ocular muscle paralysis, vision loss and even blindness. 4. Gastrointestinal manifestations: Because the basic pathological change is extensive small vessel inflammation, the digestive system is also widely involved, such as gastrointestinal bleeding, perforation or intestinal obstruction, which can be life-threatening. Liver involvement is common and may be a prominent manifestation, showing large liver, jaundice, liver pain, nausea, vomiting, mostly in the form of chronic active hepatitis. 5. Cardiovascular system manifestations: myocardium, endocardium, pericardium, conduction system, arteries and veins can be involved. Clinical manifestations include enlarged heart, accelerated heart rate, systolic murmur in the heart valve area, pericardial friction sound, high blood pressure and various arrhythmias, and in severe cases, heart failure. 6, renal manifestations: renal lesions are quite common, including interstitial inflammation, fibrosis, membranous nephropathy, glomerular basement membrane thickening, amyloidosis, etc. Clinical manifestations can be seen as swelling, polyuria or oliguria, proteinuria, hypertension and acute and chronic renal failure. 7. Other: hemolytic anemia, thrombocytopenia, oral ulcers, parotid enlargement, otitis media, pigmentation disorders, etc. may be present.