Pulmonary Vasculitis - Causes, Symptoms, Diagnosis, and Treatment

Introduction:

There are different types of vasculitis involving different parts of the body. Pulmonary vasculitis refers to the inflammation or destruction of blood vessels in the lungs. Blood vessels carry the blood throughout the body. These blood vessels are of different sizes. Small tiny blood vessels can be seen only under a microscope. It is characterized by the destruction and inflammation of pulmonary vasculature with subsequent tissue necrosis.

What Are the Symptoms of Pulmonary Vasculitis?

Pulmonary vasculitis can involve different parts of the body, and the symptoms vary. The symptoms include:

• Cough.

• Chest pain.

• Difficulty breathing.

• Hemoptysis (coughing up blood).

• Weight loss.

• Poor appetite.

• Fever.

• Tiredness.

• Rashes.

• Blood in the urine: If the kidneys are involved, blood in the urine is reported, particularly in children.

What Are the Clinical Manifestations of Pulmonary Vasculitis?

Clinically, pulmonary vasculitis is presented with:

• Pulmonary nodules.

• Alveolar hemorrhage.

• Airway diseases depend on the underlying disorder.

What Are the Classifications of Pulmonary Vasculitis?

Depending on the size of the blood vessels and the pathophysiologic mechanism of the disorder, it is classified into three types. These include:

• Small Vessel Vasculitis: Small vessel vasculitis is characterized by inflammation of small to medium-sized vessels such as capillaries, arterioles, venules, and arteries.

• Granulomatosis With Polyangiitis: Wegener’s granulomatosis is replaced with the term granulomatosis with polyangiitis. Granulomatosis with polyangiitis is a type of primary systemic antineutrophil cytoplasmic autoantibodies (ANCA) vasculitis disease (an autoimmune disease affecting small blood vessels in the body).

Clinical Manifestations:

• It commonly affects the tracheobronchial tree, upper airways, and pulmonary parenchyma. Upper airways are most commonly involved.

• Otitis hearing loss.

• Epistaxis (bleeding from the nose).

• Sinusitis (inflammation of the sinus).

• Mastoiditis (bacterial infection of the mastoid bone behind the ear).

• Septal perforation (defect of the nasal septum).

• Saddle nose deformity.

• The lower respiratory tract is also involved and presents with cough, chest discomfort, dyspnea, hemoptysis, pulmonary nodules, and alveolar hemorrhage.

• Other organs involved are the eyes, skin, joints, kidneys, nervous system, muscles, and heart.

Microscopic Polyangiitis:

• It is characterized by less pulmonary involvement and symptoms of glomerulonephritis.

• Diffuse alveolar hemorrhage.

• Other complications include pulmonary artery aneurysms, fibrotic changes, airway diseases, and infiltrates.

Churg-Strauss Syndrome: It occurs in three stages, namely-

1. An allergic or atopic phase of asthma and rhinosinusitis.

2. An eosinophilic phase- eosinophilic infiltrates develop.

3. A vasculitic phase.

• It is clinically characterized by the triad of asthma, eosinophilia, and vasculitis. Asthma usually occurs with severity, and oral corticosteroids are administered.

• Upper airway involvement is commonly involved and presents with chronic rhinosinusitis.

• Other clinical manifestations include glomerulonephritis, cardiac involvement, and cutaneous lesions.

• Cardiac complications such as coronary arteritis, cardiomyopathy, and myocarditis result in sudden death.

Henoch- Schonlein Purpura:

• In this condition, the small vessels are damaged by IgA-dominant immune deposits affecting the skin, glomeruli, and gut.

• Lung involvement is uncommon, but pulmonary hemorrhage is noticed.

Cryoglobulinemic Vasculitis: The tiny blood vessels of the skin and kidney are affected by cryoglobulin immune deposits together with circulating cryoglobulins.

Cutaneous Leukocytoclastic Angiitis: There is no involvement of any systemic disease and glomerulonephritis present in this condition.

Medium Vessel Vasculitis: The medium-sized vessels refer to the main visceral arteries, such as renal, hepatic, mesenteric, and coronary. It includes classical polyarteritis nodosa and Kawasaki disease.

Classic Polyarteritis Nodosa: The differentiating feature is found to be the lesions are present only in bronchial and not in pulmonary arteries.

Kawasaki Disease: In this disorder, coronary arteries are commonly affected in children. Hence, death occurs due to myocardial infarction. It usually occurs in children and is characterized by desquamating rash and is accompanied by mucosal ulceration.

Large Vessel Vasculitis: It is characterized by granulomatous inflammation confined to the aorta and its branches. These include:

Temporal or Giant Cell Arteritis: This condition affects mostly over 50 and is commonly associated with polymyalgia rheumatica. In addition, thoracic aortic aneurysms occur in 15 % of patients with giant cell arteritis.

Takayasu Arteritis: It usually occurs in patients younger than 50. Pulmonary involvement is not commonly seen.

How Is Pulmonary Vasculitis Diagnosed?

• Computed Tomography (CT) Scan: These tests determine the inflamed blood vessels and the areas of bleeding. In the case of small vessel vasculitis, respiratory changes are determined clearly. Pulmonary nodules are ruled out with well-defined margins of size varying from 5 millimeters to 100 millimeters. Conventional computed tomography scans can identify nodular and cavitation lesions, which are not obvious on chest X-rays. Purulent bronchorrhea has been reported as a result of the necrosis of large pulmonary masses.

• Bronchoscopy: It consists of a narrow, flexible tube with an attached camera at the end to view inside the child’s lungs.

• Lung Biopsy: A small tissue is removed from the lung under the administration of general anesthesia. Sometimes, this can be performed using keyhole surgery. A renal biopsy is recommended if the kidney is affected.

What Are the Management Approaches for Pulmonary Systemic Vasculitis?

Drug Therapy:

The use of cytotoxic immunosuppressive medications and systemic steroids are used as the main choice for the treatment of pulmonary vasculitis. Though the drug therapy has its own adverse effects, the intensity of immunosuppressive drugs should be administered based on the disease activity.

Induction Therapy:

• Patients with severe diffuse alveolar hemorrhage are treated with high-dose “pulse steroids” in combination with either Cyclophosphamide or Rituximab.

• In patients with acute renal failure and increased creatinine levels of greater than 2.5 milligrams (mg) per deciliter (dL), plasmapheresis is recommended.

• Along with pulse steroids, intravenous Rituximab or Cyclophosphamide are administered intravenously.

• Recent studies suggest that Rituximab is more effective compared to Cyclophosphamide and is considered to be an induction agent of choice.

• Initial induction therapy is continued to overcome remission and is followed in maintenance therapy.

Maintenance Therapy:

• Once remission is achieved, the dosage of glucocorticoid should be reduced gradually to the dose of fewer than 10 milligrams daily of prednisone for six months. Other pulmonary parameters, such as chest imaging, pulmonary function testing, and symptoms of dyspnea, should be closely monitored.

• If Cyclophosphamide is used as induction, the maintenance regimen of Methotrexate or Azathioprine is recommended after achieving remission.

• Recent reports suggest that Rituximab given in intervals as maintenance after induction therapy with Cyclophosphamide is found to be more effective.

Conclusion:

Pulmonary vasculitis is considered to be a life-threatening disease if left undiagnosed. An appropriate diagnosis and punctual management help to rule out the condition and aid in a better prognosis. Recent reports suggest that patient survival has improved dramatically over the last four decades. The futuristic challenge remains to design the treatment regimen to achieve maximum disease control with minimal complications associated with the treatment.