RISK FACTORS: Patients with chronic disorders, e.g., asthma, cystic fibrosis, Living or traveling in certain geographical areas, e.g., India, Ceylon, Burma, Malaysia, Indonesia, tropical Africa, South America, South Pacific
Medical Care: Give general supportive care by treating hypoxemia with supplemental oxygen. Treat bronchospasm with inhaled or nebulized bronchodilators. Inhaled corticosteroids may also be used when appropriate for persistent wheezing. Administer systemic steroids judiciously because they may worsen some infections.
" Extrinsic syndromes
o Medication-induced syndromes: These respond to the withdrawal of the offending agents, with few, if any, residual effects.
o Loeffler syndrome: Remove any potentially offending medications or ingested substances. Loeffler syndrome is mild and self-limited. Patients rarely require systemic corticosteroids.
o Parasitic infections: Once a diagnosis of parasitic infection is established, initiate therapy with appropriate antibiotics. Patients who are immunocompromised or patients taking systemic steroids with strongyloidiasis may develop hyperinfection syndrome, often associated with gram-negative septicemia and adult respiratory distress syndrome. They may require empiric antibiotic coverage and respiratory and hemodynamic support.
o Fungal causes: For ABPA, administer systemic steroids and inhaled bronchodilators. Short-term itraconazole may be used in the treatment of ABPA, as data suggest that it causes reductions in inflammatory markers and may have steroid-sparing effects. For coccidioidomycosis, the use of steroids early in infection may result in dissemination and death.
" Intrinsic syndromes
o AEP: Patients with AEP respond rapidly to high doses of systemic corticosteroids and do not tend to relapse.
o CEP: Patients with CEP respond rapidly to prednisone at a dose of 30-40 mg/d, with significant symptom improvement occurring within 48 hours and radiographic clearing occurring within 10 days. Relapse is common if steroids are discontinued in the first 6 months of therapy. Continue therapy with lower doses of prednisone for several additional months. Patients rarely require permanent steroid therapy.
o IHES: Half the patients respond to corticosteroids, but others require more aggressive therapy with busulfan, cyclophosphamide, cyclosporin-A, etoposide, azathioprine, hydroxyurea, vincristine, or interferon alfa. Imatinib is used in myeloproliferative IHES.
o CSS: Prednisone administered at a dose of 40-60 mg/d for several weeks, followed by lower-dose therapy for a total of 1 year, generally provides efficacious therapy. High doses of intravenous methylprednisolone, cyclophosphamide, and azathioprine have been used to treat patients whose conditions are refractory. In refractory cases, high-dose intravenous immunoglobulin has been reported to be helpful. Interferon-alpha and tumor necrosis factor inhibitors, such as infliximab and etanercept, have also been used.
o EG: Smoking cessation is essential. Corticosteroids are generally not beneficial.
Surgical Care: Surgical intervention is rarely necessary for patients with these syndromes. The need for open lung biopsy is rare.
" Parasitic diseases
o Echinococcal cystectomy or lung resection is the preferred treatment for this disease. Right hepatic echinococcal cysts may be removed during the echinococcal cystectomy. Often, adjuvant medical therapy is administered.
o Dirofilariasis may be difficult to distinguish from malignancy and may require transthoracic needle aspiration or resection.
" Malignancy
o Lung resection may be necessary if a solitary pulmonary nodule is present or if malignancy is in the forefront diagnostically.
o Mediastinoscopy may be necessary if lymphadenopathy, possibly representing lymphoma, is significant.
" Pneumothorax with obstructive lung disease
o This may require tube thoracostomy.
o If recurrent, such as with EG, pleurodesis may be required.
Diet: Patients who have ingested food, supplements, or medication to which the syndrome is attributed should subsequently avoid reexposure.
" Chemically related medications should be avoided.
" Measures should be taken to avoid ingestion of contaminated water or food.
" Patients should avoid incompletely cooked seafood and crustaceans.
" Patients should avoid incompletely cooked pork.
Activity: Discourage the patient from engaging in activities linked to the syndrome or encourage the patient to take measures to avoid recurrence of the syndrome.
" Patients should avoid contaminated water or soil known to harbor parasites or fungi.
" Patients should avoid close contact with animals known to harbor parasites until these animals have been decontaminated.
DRUG(S) OF CHOICE:
β’ Corticosteroid therapy. In chronic pulmonary eosinophilia, 20-40 mg prednisone daily. In Churg-Strauss
syndrome may require large doses e.g., 40-60 mg of prednisone daily. Withdrawal should be possible after recovery. In chronic conditions, treatment should continue for 6-12 months.
β’ Treat asthma, if present
β’ Piperazine for Ascaris infestation
β’ Diethylcarbamazine [available only from the manufacturer] 6-8 mg/kg orally in 3 divided doses a day for 10-14 days for tropical pulmonary eosinophilia
β’ Appropriate vermifuges for helminthic infections
ALTERNATIVE DRUGS :
β’ In Churg-Strauss syndrome, cases resistant to corticosteroid therapy, adding azathioprine or cyclophosphamide may be helpful
β’ Some patients may require oxygen therapy
PATIENT MONITORING: Physical examinations and chest x-rays until resolved
PREVENTION/AVOIDANCE : Avoid exposure to offending agent
POSSIBLE COMPLICATIONS:
β’ Some patients may show evidence of small airways dysfunction
β’ Delay in treatment of tropical pulmonary eosinophilia may result in irreversible pulmonary fi brosis
EXPECTED COURSE/PROGNOSIS :
β’ Excellent in the milder forms
β’ Corticosteroid therapy is effective in more severe cases