eosinophilic pneumonia

Also found in: Dictionary, Thesaurus, Encyclopedia, Wikipedia.
Related to eosinophilic pneumonia: chronic eosinophilic pneumonia

Eosinophilic Pneumonia



Eosinophilic pneumonia is a group of diseases in which there is an above normal number of eosinophils in the lungs and blood.


Eosinophilia is an increase in the number of eosinophils. Eosinophilic pneumonia is characterized by a large number of eosinophils in the lungs, usually in the absence of an infectious disease. Eosinophils are one of the white blood cells and are classified as a granulocyte. They are part of the non-specific immune system and participate in inflammatory reactions. Eosinophils contain cationic molecules that are useful for destroying infectious agents, especially heiminthic parasites (worms). There are several types of eosinophilic pneumonia. Loffler's pneumonia is a temporary infiltration of eosinophils into the lungs. The patient will feel tired, have a cough, spasms of the bronchial airway, and difficulty breathing. Loffler's pneumonia will clear spontaneously, but slowly over the course of about a month. Another form of eosinophilic pneumonia, pulmonary infiltrates with eosinophilia (PIE), is a more serious and potentially fatal disease. In PIE, the patient experiences asthma, pulmonary infiltrates, disorders of the peripheral nervous system, central nervous systems symptoms, and periarteritis nodosa.

Causes and symptoms

Pneumonia with eosinophils occurs as part of a hypersensitivity reaction. A hypersensitivity reaction is an over-reaction of the immune system to a particular stimulus. As part of the hypersensitive reaction, cells of the immune system are produced in increased numbers and migrate into areas targeted by the hypersensitivity reaction. In the case of eosinophilic pneumonia, the lungs are the target. Generally, eosinophilia pneumonia is not a reaction to an infection. There is a correlation between asthma and eosinophilic pneumonia. Eosinophilic pneumonia can also be caused by drugs and, in some people, by polluted air. The symptoms range from mild (coughing, wheezing, and shortness of breath) to severe and life threatening (severe shortness of breath and difficulty getting enough oxygen). The symptoms may resolve spontaneously or can persist for long periods of time. In a few cases, the disease may rapidly produce life-threatening pneumonia.


Since eosinophilia is common to a number of conditions, the physician must rule out asthma and infection by helminths when diagnosing eosinophilic pneumonia. A whole blood count will reveal an increased number of eosinophils in the blood. An x ray of the lungs may show the presence of infiltrates (the eosinophils and fluid). If sputum is produced in coughing, eosinophils will be seen instead of the more normal profile of granulocytes seen when an infectious agent is present.


Eosinophilic pneumonia may not respond to drugs used to treat asthma. Eosinophilic pneumonia is usually treated with steroids, particularly glucocorticosteroids. Steroids are not effective against infectious agents, but the main disease process in eosinophilic pneumonia is an inflammatory reaction, not a response to infection. When eosinophilia is produced as a consequence of asthma or an infection by helminths, treatment of the asthma or helminths will reduce the eosinophilia.



Berkow, Robert, editor. Merck Manual of Medical Information. Whitehouse Station, NJ: Merck Research Laboratories, 2004.

Key terms

Infiltrates — Cells or body fluids that have passed into a tissue or body cavity.
Sputum — Material coughed up from the throat or lungs.

Löff·ler syndrome I

eosinophilic pulmonary infiltrates, often associated with parasitic migration; also associated with reactions to some antibiotics, to L-tryptophan, or to crack cocaine.

eosinophilic pneumonia

inflammation of the lungs, characterized by infiltration of the alveoli with eosinophils and large mononuclear cells, pulmonary edema, fever, night sweats, cough, dyspnea, and weight loss. The disease may be caused by a hypersensitivity reaction to fungi spores; plant fibers; wood dust; bird droppings' porcine, bovine, or piscine proteins; Bacillus subtilis enzyme in detergents; or certain drugs. Treatment consists of removal of the offending allergen and symptomatic and supportive therapy. Compare bronchopneumonia. See also asthmatic eosinophilia.

Acute Pulmonary Eosinophilia

A self-limiting non-infectious inflammation in the lungs accompanied by increased eosinophils in tissue and peripheral blood.
Aetiology Unknown, or various drugs, parasitic infestation (especially ascariasis in children), nickel exposure, recent blood transfusion, or lymphangiography.
Clinical findings Chest pain, dry cough, fever, malaise, tachypnoea, dyspnoea, rash, wheezing.
Imaging Diffuse infiltrates on plain AP film.
Bronchoscopy Increased eosinophils.
Management APE may respond to corticosteroids.
Complications Restrictive cardiomyopathy due to pericardial fibrosis
Prognosis Often resolves without therapy; less commonly, it evolves to acute idiopathic eosinophilic pneumonia.

eosinophilic pneumonia

Clinical medicine A nonspecific term for disease processes in which the lung parenchyma is inflamed and diffusely infiltrated with eosinophils and histiocytes, ± PMNs, lymphocytes, plasma cells, mast cells Etiology Ancylostoma duodenale, Ascaris lumbricoides, Dirofilaria immitis, Fasciola hepatis, Necator americanus, Strongyloides stercoralis, Toxocara canis, Trichinella spiralis, Wuchereria malayi, drugs;13 are idiopathic Clinical From mild and transient–Löffler syndrome with fever, cough, and wheezing to severe and progressive–chronic EP with weight loss, dyspnea; an acute form is accompanied by respiratory failure and recuperation Clinical forms Loeffler syndrome, tropical eosinophilia, drug-induced pulmonary eosinophilia, EP associated with asthma Lab Eosinophils in BAL, peripheral blood Management Treat cause if known–eg, stop offending drug, kill offensive parasite, default to corticosteroids if idiopathic

e·o·sin·o·phil·ic pneu·mo·ni·a

(ē'ō-sin-ō-fil'ik nū-mō'nē-ă)
1. An immunologic disorder characterized by radiologic evidence of infiltrates accompanied by either peripheral blood eosinophilia or histopathologic evidence of eosinophilic infiltrates in lung tissue.
2. Eosinophilic infiltration of the lung secondary to infection or allergic reaction.


staining readily with eosin; pertaining to eosinophils or to eosinophilia.

cartilaginous eosinophilic streaks
streaks of eosinophilic matrix in cartilage. Some are normal zones of development, others represent areas of matrix degeneration and osteochondrosis.
eosinophilic chemotactic factor
a primary mediator of type I anaphylactic hypersensitivity, it is an acidic peptide (molecular weight 500) released by mast cells, which attracts eosinophils to areas where it is present.
equine eosinophilic chronic dermatitis
acanthosis and hyperkeratosis accompanied by eosinophilic granulomas in pancreas and other epithelial organs.
feline eosinophilic granuloma complex
a collective name given to the lesions of eosinophilic ulcer, eosinophilic plaque (below), and linear granuloma because of similarities in histopathology, clinical course and occasionally simultaneous occurrence in the cat.
eosinophilic granuloma
nodules or plaques that occur on skin or oral mucosa of dogs. Usually not pruritic, but oral lesions can cause some difficulties in eating. The cause is unknown. See also feline eosinophilic granuloma complex (above), equine nodular collagenolytic granuloma.
eosinophilic intestinal granuloma
see angiostrongyluscostaricensis.
eosinophilic lung disease
eosinophilic meningitis
see gnathostomaspinigerum.
eosinophilic meningoencephalitis
see sodium chloride poisoning, angiostrongyluscantonensis.
eosinophilic myocarditis
in cattle may be observed in normal animals at slaughter. Histologically there is a predominant eosinophil invasion of the heart muscle. May be accompanied by similar lesions in skeletal muscles.
eosinophilic plaque
well-defined, raised, ulcerated and extremely pruritic lesions that occur on the skin of cats, usually on the abdomen or hindlegs. There are large numbers of eosinophils present in the dermis and sometimes peripheral blood. See also eosinophilic granuloma (above), feline eosinophilic granuloma complex (above).
eosinophilic pneumonia
eosinophilic ulcer
a well-defined ulceration, usually on the upper lip of cats overlying the canine tooth, which is shallow initially but can become extremely erosive and sometimes neoplastic. Mildly irritating to the cat. Called also indolent ulcer, rodent ulcer. See also feline eosinophilic granuloma complex (above).
Enlarge picture
Bilateral eosinophilic ulcer. By permission from Kummel BA, Color Atlas of Small Animal Dermatology, Mosby, 1989
References in periodicals archive ?
However an increase in the production of interleukin (IL)-5 seems to be one of the critical pathophysiological features of eosinophilic pneumonia.
Idiopathic acute eosinophilic pneumonia in the setting of acute respiratory failure was first described in two cases in 1986.
Eosinophilic pneumonia (EP) is most often encountered in the subacute clinical setting, but it may also present with ALI and respiratory failure, termed acute eosinophilic pneumonia (AEP).
For example, acute eosinophilic pneumonia, a serious but uncommon respiratory condition diagnosed in some deployed individuals, appears to be related to new-onset smoking.
Of 183,000 military personnel deployed in or near Iraq during the study period, 18 developed acute eosinophilic pneumonia (AEP), for an incidence of 9.
The other common histologic manifestations of APL are acute eosinophilic pneumonia, acute fibrinous and organizing pneumonia, and diffuse alveolar hemorrhage with capillaritis.
Eighteen cases of acute eosinophilic pneumonia occurred from March 2003 to March 2004 among 183,000 military personnel deployed in or near Iraq.
Acute eosinophilic pneumonia is a frequent pattern of injury seen especially in EGPA.