involvement in the lungs, pulmonary infections, such as tuberculosis,
cytomegalovirus, and fungal infections, should be considered.
Coccidioidomycosis(a)is caused by the fungus C immitis. The fungus
is endemic in the southwestern United States. Conformation of the diagno-
sis is made through direct observation of the fungus in smear or culture, or
through the detection of serum antibodies. The chest radiograph generally
reveals mediastinal or hilar adenopathy, pleural effusions, nodules, cavita-
tions, or infiltrates. Mycobacterium tuberculosis(b)is the causative organism
of tuberculosis (TB). Patients can present with chronic cough, hemoptysis,
and constitutional symptoms. Because TB can present in a clinically similar
fashion as PCP in immunocompromised individuals, TB studies should also
be performed on this patient. In classic reactivation TB, pulmonary lesions
are located in the posterior segment of the right-upper lobe, apicoposterior
segment of the left-upper lobe, and apical segments of the lower lobes. In
the presence of HIV or other immunosuppressant disease, lesions are often
atypical. Up to 20% of patients who are HIV positive with active disease
have normal chest x-ray findings. Radiographic findings consistent with
active primary TB are similar to those of lobar pneumonia with ipsilateral
hilar adenopathy. Mycoplasma pneumoniae(d)is a common cause of com-
munity-acquired pneumonia in patients under the age of 40. Radiographic
findings are variable, but abnormalities are usually more striking than the
findings on physical examination. Haemophilus influenzae(e)is common
among patients with COPD, alcoholism, malnutrition, or malignancy.
62.The answer is c.(Rosen, pp 1620-1633.)The patient is having an
anaphylactic reactionto the shrimp she ate. Anaphylaxis refers to a severe
systemic allergic reaction with variable features such as respiratory difficulty,
cardiovascular collapse, pruritic skin rash, and abdominal cramping. Ana-
phylaxis is a hypersensitivity reaction caused by an IgE-mediatedreaction.
Foods are the major cause in cases of anaphylaxis in which a source can be
determined. Common foods that cause anaphylaxis include nuts, shellfish,
andeggs. In the ED, attention is focused on reversing cardiovascular and
respiratory disturbances. Epinephrineis the first drug of choice for patients
with anaphylaxis. The route of administration is chosen by the severity of the
patient’s presentation. In a patient with upper airway obstruction or hypoten-
sion, IV epinephrine should be administered. Patients with stable vital signs
can receive subcutaneous epinephrine. Epinephrine should be used with
caution in the elderly or any patient with coronary artery disease or dys-
rhythmias. Antihistamines, such as diphenhydramineand ranitidine, should
70 Emergency Medicine