Pulmonary Pathology Online
Pathology of Pulmonary Hemorrhage:
Goodpasture's Syndrome and other forms of Intrapulmonary Hemorrhage
Bleeding from pulmonary capillaries occurs in many settings.
Bilateral extensive pulmonary hemorrhage is generally a complication of other diseases, such as mitral stenosis or rarely infection.
It also occurs in Goodpasture’s syndrome.
Hemorrhage is common at autopsy in severe heart failure where it probably results from a combination of hemodynamic factors and alveolar injury.
In thrombocytopenic patients minor alveolar injury can result in hemorrhages in leukemic patients.
There remains a small group of patients in whom repeated episodes of pulmonary hemorrhage occur in the absence of any discernible predisposing illness.
Goodpasture, a Boston pathologist, was investigating the autopsy findings in influenza pandemic deaths just after World War I.
In one case in which death occurred several weeks after the attack of influenza, the lung showed extensive bilateral hemorrhage, together with necrotizing angiitis of the systemic vessels and glomerulonephritis.
Since then the term Goodpasture’s syndrome has been applied to the condition of diffuse bilateral pulmonary hemorrhage accompanied by rapidly progressive glomerulonephritis.
Antiglomerular Basement Membrane Disease:
Goodpasture’s disease has now become synonymous with the variant of pulmonary hemorrhage associated with circulating antiglomerular basement membrane antibodies.
In this disease antibodies are visualized in the kidney (and less well in the lung) by immunoflourescence as linear staining of the basement membrane.
Although the patients may be adults of any age, they are typically young men and present with hemoptysis, dyspnea, and acute renal disease.
Either the renal symptoms or the pulmonary symptoms may come first.
As in Wegener’s granulomatosis, the renal symptoms are more important than the pulmonary symptoms for the outcome.
Anemia from pulmonary bleeding is usual.
Radiographic examination reveals diffuse bilateral alveolar filling.
The diagnosis is made on the basis of renal biopsy.
Histologically, the alveoli are filled with red blood cells and there is suggestive evidence of "alveolitis" in the form of neutrophils in and around alveolar capillaries.
Radiologically, the lesions involve rapidly in a matter of days as the red cell lyse and are then phagocytosed.
At this stage hemosiderin-laden macrophages are found in the alveolar space and in the interstitium.
On gross examination, the lungs are dark red and heavy in the acute phase and rusty brown when the red cells are phagocytosed.
Treatment by bilateral nephrectomy has been superseded by the administration of cytotoxic drugs. Plasmapheresis has also been used to remove the antibodies. The disease is no longer uniformly fatal. The basal laminae of the capillaries in the lungs and the glomuruli are thought to have common antigenic determinants that are targets for antibodies elicited by a primary lung insult or kidney injury. The resulting damage to the basal laminae produces alveolitis and hemorrhage in the lung and rapidly progressive glomerulonephritis in the kidney.
Other Forms of Intrapulmonary Hemorrhage:
An identical clinical and pathologic syndrome occurs in the absence of circulating antiglomerular basement membrane antibodies in about half the cases of otherwise typical Goodpasture’s syndrome.
A similar syndrome may also occur in the collagen-vascular diseases.
As in Goodpasture’s syndrome, necrotizing angiitis may be an associated feature.
Wegener’s granulomatosis may present as diffuse pulmonary haemorrhage (Example: upper respiratory tract lesions or infectious granulomas of the lung).
Systemic lupus erythematosus may also present as pulmonary hemorrhage.
Evidence of pulmonary hemorrhage, usually old, is commonly found in patients with renal failure.
The renal failure may be due to several other causes. Only those with rapidly progressive glomerulonephritis should be regarded as examples of Goodpasture’s syndrome.
Idiopathic Pulmonary Hemorrhage:
Primarily of interest to the pediatrician, idiopathic pulmonary hemorrhage presents as hemoptysis and anemia in patients under 20 years of age.
Radiologic features are similar to those of Goodpasture’s syndrme, but this disease differs in that renal disease is absent, the pulmonary hemorrhages are recurrent and intermittent, and the course is much more protracted or the disease remits spontaneously.
Because of the chronicity of the course, the morphologic lesions differ from those in Goodpasture’s syndrome.
Although the acute lesions are similar, acute alveolitis may not be present, and there may discontinuity of the alveolar basement membranes.
With repeated hemorrhages the elastic tissue of the alveolar walls and blood vessels becomes coated with iron and calcium (presumably dystrophic) and is rendered basophilic.
Fragmentation of elastic fibers leads to foreign body giant cell reaction. The etiology is unknown.
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