Wallach's Interpretation of Diagnostic Tests: Pathways to Arriving at a Clinical Diagnosis (577 page)

   In patients with chronic cough, the diagnosis of UACS-induced cough should be determined by considering a combination of criteria, including symptoms, physical examination findings, radiographic findings, specific allergen testing (to check whether acquired hypogammaglobulinemia is present) and, ultimately, the response to specific therapy. Because UACS is a syndrome, no pathognomonic findings exist.

   Specific therapy is instituted when the cause of chronic cough is apparent; empiric therapy should be considered in cough of unknown etiology.

Suggested Reading

Pratter MR. Chronic upper airway cough syndrome secondary to rhinosinus diseases (previously referred to as postnasal drip syndrome): ACCP evidence-based clinical practice guidelines.
Chest.
2006;129(1 Suppl): 63S–71S.

   
DYSPNEA

   Definition

“Dyspnea” is a term used to characterize a subjective experience of breathing discomfort that comprises qualitatively distinct sensations that vary in intensity (American Thoracic Society guidelines, 2012). The experience derives from interactions among multiple physiologic, psychological, social, and environmental factors and may induce secondary physiologic and behavioral responses. It is a common symptom that afflicts millions of patients with pulmonary disease.

   The majority of patients with chronic dyspnea of unclear etiology have one of four diagnoses: asthma, COPD, interstitial lung disease, or myocardial dysfunction. Mild dyspnea is common. Dyspnea is a common chief complaint among patients who come to the emergency department. The majority of life-threatening causes of dyspnea are classified below.

   Life-threatening upper airway causes: tracheal foreign objects, angioedema, anaphylaxis, infections of the pharynx, and neck and airway trauma

   Life-threatening pulmonary causes: pulmonary embolism, COPD, asthma, pneumothorax, pulmonary infections, ARDS, direct pulmonary injury, and pulmonary hemorrhage

   Life-threatening cardiac causes: ACS, flash pulmonary edema, high-output heart failure, cardiomyopathy, cardiac arrhythmia, valvular dysfunction, and cardiac tamponade.

   Life-threatening neurologic causes: stroke, neuromuscular disease

   Life-threatening toxic and metabolic causes: poisoning, salicylate poisoning, carbon monoxide poisoning, DKA, sepsis, anemia, and acute chest syndrome

   Other miscellaneous causes include lung cancer, pleural effusion, ascites, pregnancy, hyperventilation, anxiety, and massive obesity.

   The combination of all historical elements and physical examination findings is helpful in diagnosing the cause of both acute and chronic dyspnea.