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* last one on aspergillosis!
 #134409  
  dolly123 - 10/31/06 22:29
 
  A 13-year-old boy comes to his physician with fever and breathlessness for the past two days. For the past 4 years he has been having persistent cough associated with occasional expectoration of brownish mucus plugs. Repeated chest X-rays showed transient pulmonary infiltrates in different lung zones. He was started on antibiotics for these symptoms. He also has mild asthma for which he takes inhaled albuterol. His immunizations are up-to-date and has a normal height and weight. Chest examination is normal. Chest X-ray shows pulmonary infiltrates in lower lung zones. Laboratory testing shows hematocrit of 39%, WBC count of 12,000/microL with eosinophils of 32%, platelet count of 170,000/microL, serum IgA of 150mg/dL, IgG of 800mg/dL, IgM of 170mg/dL, and IgE of 1300 IU/mL. Based on these findings, what is the most likely diagnosis in this patient?

A. Job syndrome
B. Wiskott Aldrich syndrome
C. Allergic bronchopulmonary aspergillosis
D. Chronic eosinophilic pneumonia
E. Churg Strauss syndrome


Explanation:
Acute bronchopulmonary aspergillosis (ABPA) is characterized by transient recurrent pulmonary infiltrates, peripheral eosinophilia, asthma and immediate wheal and flare reaction to Aspergillus fumigatus and presence of antibodies in the serum against Aspergillus fumigatus. Other important features include history of brownish plugs in the sputum and high IgE levels. Sometime bronchiectasis is also present in this disorder, and is due to immune complex deposition. Glucocorticoids are used to treat this disorder. The patient presented in the above vignette has many features typical of ABPA. These include recurrent transient pulmonary infiltrates, presence of brownish plugs in the sputum, elevated IgE levels and peripheral eosinophilia. Whenever a patient with asthma is suspected of having ABPA, skin testing with A. antigen is the first diagnostic step because if the reaction is negative, diagnosis of ABPA is ruled out. If the test is positive, serum precipitins against Aspergillus fumigatus and IgE level are checked. ABPA is excluded if IgE levels are less than 1000ng/ml or if serum precipitins against Aspergillus fumigatus are absent.

Job Syndrome is characterized by recurrent bacterial infections and markedly elevated IgE levels. Bacterial infections in Job syndrome are usually caused by staphlococci and the skin is the most frequent site of involvement. Neutrophils exhibit impaired chemotaxis. Some patients have coarse features while others are fair. Other allergic disorders like eczema, asthma, allergic rhinitis may be present. Treatment is intermittent or continuous antibiotics. The patient presented in the above vignette has no evidence of skin infections that makes this disorder very unlikely.

Wiskott-Aldrich syndrome is a rare, X-linked immunodeficiency syndrome characterized by the triad of eczema, thrombocytopenic purpura and recurrent pyogenic infections. IgE and IgA levels are high while IgM levels are low. Lymphoreticular malignancies are common in such patients. The patient presented in the above vignette has normal platelet count and normal IgA and IgM levels thus making this disorder unlikely.

Chronic Eosinophilic Pneumonia (CEP) is the most common eosinophilic pneumonia in the US. Patients with chronic eosinophilic pneumonia present with systemic symptoms of fever, malaise, anorexia and weight loss for several weeks or months. Pulmonary symptoms include cough and breathlessness. Sometimes patients have history of bronchial asthma or allergic rhinitis. Chest auscultation shows crackles or wheezing. Chest X-ray reveals peripheral infiltrates that are photographic negative of pulmonary edema and this radiographic finding is pathognomonic of this chronic eosinophilic pneumonia. BAL usually shows eosinophils greater than 40% and this finding is suggestive of chronic eosinophilic pneumonia. Glucocorticoid therapy results in rapid resolution of symptoms and radiographic clearing.

Churg-Strauss syndrome is a multisystem vasculitic disorder of unknown etiology that affects skin, kidney, nervous system, lungs, gastrointestinal system and heart. There is usually a history of asthma followed by the development of fever and marked eosinophilia at which time asthma may have become better. The disease is severe and requires treatment with glucocorticoids and sometimes with immunosuppressants. Churg Strauss syndrome is unlikely in this patient as there is no evidence of any organ involvement other than lungs.

Educational Objective:
Acute bronchopulmonary aspergillosis (ABPA) is characterized by transient recurrent pulmonary infiltrates, peripheral eosinophilia, asthma and immediate wheal and flare reaction to Aspergillus fumigatus and presence of antibodies in the serum against Aspergillus fumigatus

 
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