Uncommon causes of cough: ACCP evidence-based clinical practice guidelines.

OBJECTIVES: To describe the uncommon causes of cough.

DESIGN/METHODOLOGY: An English language literature search by MEDLINE citations from 1975 through 2004 was used to identify publications on uncommon pulmonary and nonpulmonary disorders in which cough was present as the major or presenting symptom in >50% of those persons affected by the uncommon diseases.

RESULTS: A substantial number of uncommon or rare pulmonary and nonpulmonary disorders were identified. The uncommon occurrence of these diseases made it difficult to develop a meaningful evidence-based guideline to the diagnosis and therapy of many of the uncommon causes of cough. As cough was the major or presenting symptom, it was usually initially attributed to common respiratory diseases (eg, asthma or bronchitis). As a result, a substantial time lag existed from the onset of cough to the diagnosis of the etiologic entity. Diagnostic tests limited to the respiratory system did not always provide clues to the diagnosis of uncommon causes of cough.

CONCLUSIONS: Cough is the major or presenting symptom in many uncommon pulmonary and nonpulmonary disorders. A strong index of suspicion is essential to consider and diagnose the uncommon causes of cough. The diagnosis and management of cough in patients with uncommon causes of cough is dependent on the underlying etiology.