Diffuse Alveolar Hemorrhage
Amber A. Afshar
Richard D. Brasington
General Principles
Diffuse alveolar hemorrhage (DAH) encompasses a heterogeneous group of pulmonary and nonpulmonary disorders characterized by widespread intra-alveolar bleeding.
DAH is a medical emergency that can result in acute respiratory failure and death.
The exact incidence and prevalence of DAH are unknown owing to the variety of underlying etiologies but the most common cause of DAH appears to be systemic vasculitis, in particular granulomatosis with polyangiitis (GPA) (Fig. 19-1).1,2
The pathogenesis of DAH is thought to be secondary to direct effects of autoantibodies on the alveolar capillary endothelium.
Differentiation from localized etiologies (Table 19-1) of pulmonary hemorrhage is difficult to ascertain on history and physical examination alone; diagnostic procedures such as CXR and fiberoptic bronchoscopy are often needed.
 FIGURE 19-1. Causes of diffuse alveolar hemorrhage. ABMA, antibasement membrane antibody–mediated disease; CTD, connective tissue disease; IPH, idiopathic pulmonary hemorrhage; PRS, pulmonary renal syndromes. (Data from Travis WD, Colby TV, Lombard C, et al. A clinicopathologic study of 34 cases of diffuse pulmonary hemorrhage with lung biopsy confirmation. Am J Surg Pathol. 1990;14:1112–25.) |
TABLE 19-1 CAUSES OF LOCALIZED PULMONARY HEMORRHAGE | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
Diagnosis
Appropriate diagnosis of DAH requires high clinical suspicion and a thorough history and physical examination.
Rapid diagnosis of DAH is mandatory given the potential for excessive morbidity (renal failure, restrictive and obstructive lung disease) and mortality rates approaching 70–80% in untreated subsets of patients.
Clinical Presentation
DAH should be suspected whenever a patient presents with hemoptysis, dyspnea, and a predisposing condition, such as an underlying connective tissue disorder, systemic vasculitis, or certain drug or occupational exposures.
Hemoptysis, a presumed cardinal symptom of DAH, may be absent in up to one-third of cases despite pronounced and life-threatening alveolar hemorrhage.
A detailed history of past and present medications (prescribed, over-the-counter, and recreational) and occupational exposures should be obtained.
Amiodarone, retinoic acid, sirolimus, penicillamine, and crack cocaine have all been implicated as causative agents of DAH.3
Inhalation of trimellitic anhydride, a chemical found in paints, varnishes, and plastics, has also been reported as a cause of DAH.
Physical examination findings are nonspecific and may include fever, hypoxemia, tachypnea, and diffuse crackles.
Signs suggesting an underlying systemic disorder should be sought. These signs may include sinusitis, iritis, oral ulcers, arthritis, synovitis, palpable purpura, neuropathy, and cardiac murmurs.
Differential Diagnosis
DAH is infrequently the initial presentation of an underlying systemic disorder (Table 19-2 and Fig. 19-1).1,2,3,4,5,6,7,8,9,10,11,12,13,14 Twenty percent of patients with systemic lupus erythematosus (SLE) and 5–10% of patients with Goodpasture syndrome present with DAH as the initial or sole manifestation. Therefore, emphasis should be placed on the rheumatologic, renal, pulmonary, and cardiac review of systems.
Diagnostic Testing
Laboratories
Laboratory evaluation is crucial for the diagnosis of DAH.
Complete blood count
TABLE 19-2 CAUSES OF DIFFUSE ALVEOLAR HEMORRHAGE
Rheumatologic
Systemic lupus erythematosus5
Rheumatoid arthritis6
Mixed connective tissue disorder6
Systemic sclerosis
Juvenile rheumatoid arthritis
Polymyositis
Hematologic
Autologous or allogeneic stem cell transplant7
Thrombotic thrombocytopenic purpura8
Idiopathic thrombocytopenic purpura
Disseminated intravascular coagulation
Cryoglobulinemia
Antiphospholipid antibody syndrome9
Multiple myeloma
Vasculitis
Behçet disease
Cryoglobulinemia
Goodpasture syndrome
Granulomatosis with polyangiitis (Wegener granulomatosis)
Henoch–Schönlein purpura
Microscopic polyangiitis
Pulmonary
Isolated pauci-immune pulmonary capillaritis
Idiopathic pulmonary fibrosis
Idiopathic pulmonary hemosiderosis
Acute lung transplant rejection
Pulmonary venoocclusive disease
Pulmonary capillary hemangiomatosis
Renal
IgA nephropathy
Idiopathic glomerulonephritis
Poststreptococcal glomerulonephritis
Cardiac
Mitral stenosis
Bacterial endocarditis
Gastrointestinal
Ulcerative colitis
Medication/drugs
Abciximab10
Amiodarone11
Crack cocaine3
Nitrofurantoin
Penicillamine
Propylthiouracil
Phenytoin
Retinoic acid12
Sirolimus13
Tirofiban10
Warfarin14
Occupational exposures
Trimellitic anhydride
Radiation exposure
Asbestosis
Welder pneumoconiosis
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
