Idiopathic Hypereosinophilic Syndrome

Idiopathic hypereosinophilic syndrome (HES) includes a heterogeneous group of disorders defined by:

1. A persistent eosinophilia of >1500/mm3 for longer than 6 months

2. Absence of evidence of known causes of eosinophilia despite a comprehensive workup for such causes ro go

Idiopathic hypereosinophilic syndrome (HES)

Eosinophilic leukemias, i.e., eosinophils being part of malignant clone

Clonal

Eosinophilia associated with noneosinophilic clonal disorders as a result of eosinopoietic cytokines released by clonal cells

Nonidiopathic

Nonclonal reactive (see Table 9-12)

Anaemia Classification Tables
Fig. 9-2. Etiologic classification of eosinophilia.

ro go oo

Idiopathic Hypereosinophilic Syndrome

Th=Helper T lymphocytes

GM-CSF=Granulocyte macrophage colony-stimulating factor

Th=Helper T lymphocytes

GM-CSF=Granulocyte macrophage colony-stimulating factor

Fig. 9-3. Mechanism of eosinophil production in bone marrow, release in circulation, and migration in tissue.

3. Signs and symptoms of organ involvement directly attributable to eosinophilia, including hepatomegaly, splenomegaly, heart disease, diffuse or focal central nervous system (CNS) abnormalities, pulmonary fibrosis, fever, weight loss, or anemia (i.e., evidence of end organ damage with histologic demonstration of tissue infiltration by eosinophils or objective evidence of clinical pathology in any organ system associated with eosinophilia and not clearly attributable to another cause).

Epidemiology

HES most commonly occurs between the ages of 20 and 40 years with a male to female ratio of 4:1. Clinical manifestations of HES in the pediatric age group are similar to HES in adult patients. In children HES may be associated with trisomy 8 or trisomy 21.

Clinical Presentation

The disease generally has a gradual onset. The chief complaints include anorexia, fatigue, weight loss, recurrent abdominal pain, fever, night sweats, persistent nonproductive cough, chest pain, pruritus, skin rash, and congestive heart failure.

Organ Involvement

Cardiovascular Disease

HES-associated heart disease evolves through three stages:

1. Early acute phase, associated with degranulating eosinophils in the heart muscle (5-6 weeks into eosinophilia)

2. Subacute thrombotic stage (10 months into eosinophilia)

3. Chronic stage of fibrosis (24 months into eosinophilia). Cardiac disease involves both ventricles and can cause incompetence of mitral and tricuspid valves.

Coagulation System

Eosinophilia can cause a hypercoagulable state, the etiology of which is unclear. Eosinophil major basic proteins inactivate thrombomodulin, resulting in the unavailability of activated protein C. Intracardiac thrombus, deep-venous thrombosis, dural sinovenous thrombosis, and/or arterial thrombosis can occur.

Nervous System Complications

• Encephalopathy (altered behavior and cognitive function)

• Thrombotic strokes

• Peripheral neuropathies including mononeuritis multiplex, symmetrical senso-rimotor neuropathy, and radiculopathy

• Retinal hemorrhages.

Gastrointestinal Complications

• Hepatomegaly due to eosinophilic infiltration of the liver results in liver function abnormalities.

• Enteropathy due to blunting of the villi and cellular infiltration in the lamina propria results in diarrhea and fat malabsorption.

• Eosinophilic infiltration of colon results in colitis.

Spleen

Splenomegaly with disruption of its architecture can occur. Dermatologie Manifestations

The most common lesions include pruritic papules and nodules, urticarial plaques, and angioedema. Vesiculobullous lesions, generalized erythroderma, and aquagenic pruritus occur in some patients. Digital necrosis may result from vasculitis and microthrombi.

Pulmonary Complications

Nocturnal cough, fever, and diaphoresis can occur due to accumulation of eosinophils in the lungs. Pulmonary fibrosis can also occur.

Treatment

Table 9-13 lists the treatment of idiopathic HES.

Your Heart and Nutrition

Your Heart and Nutrition

Prevention is better than a cure. Learn how to cherish your heart by taking the necessary means to keep it pumping healthily and steadily through your life.

Get My Free Ebook


Post a comment