Eosinophilic Lung Diseases

Author: V. Dimov, M.D., Allergist/Immunologist and Assistant Professor at University of Chicago
Reviewer: S. Randhawa, M.D., Allergist/Immunologist and Assistant Professor at LSU (Shreveport) Department of Allergy and Immunology

Pulmonary Infiltrates with Eosinophilia (PIE) Syndromes are a heterogeneous group of lung diseases.


Pulmonary Infiltrates with Eosinophilia (PIE)

Acute Eosinophilic Pneumonia (AEP)

AEP occurs in young and generally healthy people. Blood eosinophilia is often absent but eosinophils make 25-60% of BAL cells.

AEP is characterized by:

- acute febrile illness
- absence of infectious cause
- hypoxemia and respiratory failure
- pulmonary infiltrates
- eosinophils present in BAL or lung biopsy
- excellent therapeutic response to corticosteroids
- no recurrence of infiltrates after stopping CS

Treatment of AEP is with high-dose methylprednisolone, 1 mg/kg IV q 6 hours.

Chronic Eosinophilic Pneumonia (CEP)

CEP presents with chronic SOB and cough for weeks or months. In contrast to AEP, it rarely progresses to respiratory failure. 50% of patients with CEP have a history of asthma. Blood eosinophil counts may be normal in both AEP and CEP. CEP respond rapidly (within 48 hours) to CS.

Drug-induced PIE

Many drugs: ASA, phenytoin, heroin and cocaine.

Infectious PIE

Pneumocystis carinii pneumonia, fungal pneumonia, and parasitic infections can present with pulmonary infiltrates with eosinophilia.

Tropical pulmonary eosinophilia

Due to an immune response to bloodborne microfilaria carried to the lungs (Wuchereria bancrofti). IgE anti-filarial antibodies are diagnostic.

Löffler’s syndrome

Due to transpulmonary passage of helminths - Ascaris and Strongyloides.

Allergic Bronchopulmonary Aspergillosis (ABPA) (click to read the details)

Churg-Strauss vasculitis

Churg-Strauss vasculitis is a small vessel necrotizing vasculitis with very high blood eosinophilia (greater than 1000/μL). It affect asthmatics requiring CS. Churg−Strauss is distinguished from other PIE by extrapulmonary manifestations:

- sinusitis
- eosinophilic gastroenteritis
- cardiomyopathy
- focal segmental glomerulonephritis (FSGN)
- purpura or urticaria
- mononeuritis multiplex or polyneuropathy

Churg−Strauss is diagnosed by biopsy, p-ANCA (perinuclear pattern) are positive in 50-75% of cases.

Conditions with elevated IgE

Atopic dermatitis, Asthma, ABPA, and allergic fungal sinusitis

Infections (parasites, HIV, TB, EBV, and CMV)

Malignancy (IgE myeloma and lymphoma)

Churg-Strauss syndrome

Kimura’s disease, painless, unilateral cervical lymphadenopathy or subcutaneous masses in the head or neck region

Immunodeficiency diseases with elevated IgE

Hyper IgE syndrome (HIES)

Wiskott-Aldrich syndrome (WAS)

Omenn syndrome

DiGeorge syndrome (DGS)

Netherton syndrome, form of ichthyosis associated with SPINK5

Nezelof syndrome, congenital hypoplasia of the thymus with retention of normal parathyroid function (in contrast to complete DiGeorge syndrome in which there is absence of the parathyroids)

Hypereosinophilic syndrome (HES)

HES is characterized by high blood eosinophilia (greater than 1500/μL) for longer than 6 months, no identifiable cause, and multiple organ involvement. HES rarely affects lungs.

References

Allergy and Immunology MKSAP, 3rd edition.
More Than Asthma: Allergic Bronchopulmonary Aspergillosis. NEJM Images in Clinical Medicine, 08/2008.
Allergic Bronchopulmonary Aspergillosis: Challenges in Diagnosis. Viswanath P. Kurup, PhD, Banani Banerjee, PhD, Paul A. Greenberger, MD, and Jordan N. Fink, MD. Medscape General Medicine, 12/23/1999.
Allergic Bronchopulmonary Aspergillosis. MK Cheezum, CJ Lettieri. Medscape Allergy & Clinical Immunology, 2008.
Allergic Bronchopulmonary Aspergillosis (ABPA). Russell Blair, MD; Jeremy S. Breit, MD; Stephen P. Peters, MD, PhD. Merck Manual, 2008
Allergic Bronchopulmonary Aspergillosis. Ritesh Agarwal. CHEST March 2009 vol. 135 no. 3 805-826.
Aspergillosis. NEJM, 04/2009.

Published: 02/08/2008
Updated: 08/22/2010