The differential appears rather complete. You review the possibilities and assist the medical student with an analysis of the case.

Dyspnea: The patient has known asthma and the physical exam with inspiratory and expiratory wheeze is consistent with an exacerbation of his reactive airway disease. His history of fever and minimal relief following treatment for asthma in the ED less than 24 hours ago, you must also consider an infectious process and rule out pneumonia.

Rash: The rash is macular with palmar distribution, plus there is desquamation of the digits. An allergic reaction is possible, however digit desquamation is unusual in such cases. Many infectious processes may present with both respiratory and skin manifestation. Viruses generally spare palms; bacteria, mycoplasma and rickettsia cause palmar manisfestation; bacteria is the most common of the three.

A drug reaction is unlikely since he denies using any new medications or illicit substances.

Exposure to several different toxins can cause rash, including pesticides, metals and solvents. You recommend the student perform an internet search to help him determine which toxins may cause these symptoms.

Autoimmune diseases and syndromes such as lupus and vasculitis may (needs to be completed).