Wallach's Interpretation of Diagnostic Tests: Pathways to Arriving at a Clinical Diagnosis (591 page)

Suggested Readings

Kruip MJ, Leclercq MG, van der Heul C, et al. Diagnostic strategies for excluding pulmonary embolism in clinical outcome studies. A systematic review.
Ann Intern Med.
2003;138:941.

Roy PM, Colombet I, Durieux P, et al. Systematic review and meta-analysis of strategies for the diagnosis of suspected pulmonary embolism.
BMJ.
2005;331:259.

Wolf SJ, McCubbin TR, Nordenholz KE, et al. Assessment of the pulmonary embolism rule-out criteria rule for evaluation of suspected pulmonary embolism in the emergency department.
Am J Emerg Med.
2008;26:181.

DRUG-INDUCED PULMONARY DISEASES

   Definition

   Drug-induced pulmonary disease (DIPD) represents a heterogeneous group of disorders, a common clinical problem in which a patient without previous pulmonary disease develops respiratory symptoms, chest x-ray changes, deterioration of pulmonary function, histologic changes, or several of these findings in association with drug therapy. More than 150 drugs or categories of drugs have been reported to cause pulmonary disease; the mechanism is rarely known.

   Depending on the drug, drug-induced syndromes can produce asthma, bronchiolitis, hypersensitivity infiltrate, interstitial fibrosis, organizing pneumonia, asthma, noncardiogenic pulmonary edema, pleural effusions, pulmonary eosinophilia, pulmonary hemorrhage, or venoocclusive disease. DIPDs can present a variety of clinical presentations and radiographic patterns. A good resource for details on different DIPDs and their clinical and radiographic presentation is available at
www.pneumotox.com

   Causal drugs

   In cardiovascular drugs, amiodarone is a classic example that caused pulmonary toxicity. In 3–20% of patients, ACE inhibitors induce a dry, persistent, and often nocturnal cough that may require discontinuation of the drug.

   Among anti-inflammatory agents, aspirin triad characterized by asthma, nasal polyposis, and drug sensitivity.

   Many chemotherapeutic and immunosuppressive drugs including bleomycin, mitomycin-C, busulfan, cyclophosphamide, and nitrosourea drugs are implicated.

   Who Should Be Suspected?

   Many types of lung injury can result from medications, and it is often impossible to predict who will develop lung disease resulting from a medication or drug. Symptoms may vary from patient to patient. The most common symptoms include cough, wheezing, shortness of breath, chest pain, bloody sputum, and fever. Many drugs can induce alveolar inflammation, interstitial inflammation, and/or interstitial fibrosis, resulting in lung dysfunction.

   Diagnostic Findings

There is no clear-cut laboratory or radiographic testing of the clinical syndromes associated with DIPD. The diagnosis is usually one of exclusion. Plain chest x-rays may miss or underestimate the presence of lung disease at the time of initial presentation. Diagnosis is based on observation of responses to withdrawal from and, if practical, reintroduction to the suspected drug. Echocardiography may rule out cardiac disease, sputum studies may rule out infectious diseases, and ANA or RF testing may be helpful in suspected cases of collagen vascular disease.

   Pulmonary function: Testing is useful in assessing the toxicity.