A 60-year-old male farmer and cattle owner presented to the emergency department with generalized urticaria and angioedema, syncope, and severe hypotension. His leukocyte count revealed 430 eosinophils/mm³, results of serologic testing with passive hemagglutination were positive for hydatidosis, total IgE concentration was normal (60 IU/mL), and results of a radioallergosorbent assay for Echinococcus (Pharmacia Diagnostics, Uppsala, Sweden) were positive (class 3). Results of chest radiography, abdominal ultrasonography, and abdominal computed tomography were unremarkable. Systemic anaphylaxis, probably secondary to the rupture of a hidden hydatidic cyst, was diagnosed. During follow-up in the allergy department, hydatid serologic titers progressively decreased.

A year later, the patient presented with paresis of the left upper extremity. The paresis progressed, affecting all the movements of the hand, and was associated with exaggerated deep tendon reflexes. Cerebral computed tomography showed a cystic lesion in the right parietal region (Figure 1). Results of transthoracic echocardiography and abdominal computed tomography were negative. Surgery revealed three hydatidic cysts.

View larger version (121K): [in this window] [in a new window]   Figure 1. Cerebral computed tomographic scan. Spindle-shaped cystic lesion with a thin wall that did not take contrast in the right parietal region.

Eight months later, the patient developed headache and progressive right hemihypoesthesia. Cerebral computed tomography showed two cystic formations in the left parietal region and one in the right occipital area, which again required surgical intervention.

Hydatid disease is an anthropozoonosis, endemic in Spain, caused by Echinococcus granulosus. It may remain clinically silent or may produce symptoms, depending on the location of the cyst. Anaphylactic symptoms are unusual (1%) [1]. The location of the cyst in the different organs is related to the normal cycle of the echinococcus in the organism; the liver is the most common location. The brain is involved in only 2% of cases of hydatid disease [2]. Cysts are more common in children [4]. Cerebral hydatid cysts are usually single and grow slowly. Neurologic deficits appear late [3]. The diagnosis of neurohydatidosis is based on the presence of a noncontrasting cystic image on the scan with cysts in other locations or positive results on serologic tests, or both [5].

Our case of hydatid disease was diagnosed by blood eosinophilia, positive serologic test results, and determination of specific IgE, but the initial imaging studies failed to reveal cysts. This case is of interest because of its unusual initial manifestation as anaphylactic shock and the development of multiple cerebral cysts in an adult.

It may be prudent to extend the search for hydatidic cysts to less frequent locations when faced with a serologic diagnosis of hydatidosis.