Multi-organ echinococcosis in a paediatric patient

The 3-year-old patient presented with acute-onset respiratory distress and temperature spikes. The patient had had a chronic cough for 3 months prior to this point. Auscultation of the lungs revealed bilateral coarse crackles, while the rest of the physical examination was unremarkable. A chest X-ray (CXR) showed bilateral well-defined rounded opacities involving all the lung zones (Fig. 1). A CT (computed tomography) scan of the chest revealed the cystic nature of these pulmonary lesions, while a CT scan of the abdomen demonstrated further cystic lesions in the spleen and the liver (Figs 2 and 3). The indirect haemagglutination (IHA) serological test was positive for hydatid disease. The Multi-organ echinococcosis in a paediatric patient


Introduction
Echinococcosis (hydatid disease) is a potentially fatal disease that can affect animals and humans.Patients usually become symptomatic when larval cysts elicit space-occupying effects.By this stage, extensive multiorgan involvement may be present, as was demonstrated in this case.

Case report
The 3-year-old patient presented with acute-onset respiratory distress and temperature spikes.The patient had had a chronic cough for 3 months prior to this point.Auscultation of the lungs revealed bilateral coarse crackles, while the rest of the physical examination was unremarkable.A chest X-ray (CXR) showed bilateral well-defined rounded opacities involving all the lung zones (Fig. 1).A CT (computed tomography) scan of the chest revealed the cystic nature of these pulmonary lesions, while a CT scan of the abdomen demonstrated further cystic lesions in the spleen and the liver (Figs 2 and 3).The indirect haemagglutination (IHA) serological test was positive for hydatid disease.The   patient was commenced on albendazole, prednisone and Berotec, and responded well.A follow-up CXR after 3 months' treatment showed marked improvement of the lesions (Fig. 4).

Discussion
Echinococcosis is an infection caused in humans by the larval stage of Echinococcus granulosis, E. multilocularis, or E. vogeli.E. granulosis produces unilocular cysts and is most prevalent in areas where livestock is raised in association with dogs. 1 Humans are accidental hosts and are infected by the ingestion of ova from fomites or contaminated water, and by direct contact with dogs.After ingestion, embryos escape from the ova, penetrate the intestinal mucosa and enter the portal system, from where they are carried to various organs, most commonly the liver and the lungs.Here they develop into mature larval cysts. 2 Unless these slowly enlarging cysts elicit spaceoccupying effects on specific organs, an infected patient would usually remain asymptomatic.Pulmonary symptoms include cough, chest pain and haemoptysis, while hepatic involvement may cause fever, right upper quadrant pain, pruritis, urticaria, or eosinophilia.Other presentations may include anaphylaxis, pathological fractures, neurological deficit, pericarditis, arrhythmias and pelvic masses. 2 Radiographic imaging studies are important in detecting and evaluating echinococcal cysts.Plain films will reveal unruptured pulmonary cysts as rounded masses of uniform density, while ruptured cysts result in complex cavitary lesions with variable radiographic features, which include an air-fluid level, a floating membrane (water-lily sign), a double wall, an essentially dry cyst with crumpled membranes (serpent sign, rising sun sign) or an empty cyst. 2,3lain films may also be helpful in detecting cysts in other organs, e.g.calcified cysts in the liver.Ultrasound, CT and MRI may all reveal well-defined cysts with thick or thin walls.On CT, it is occasionally possible to demonstrate daughter cysts within a larger cyst; this has the characteristic appearance of eggshell or mural calcification and is virtually pathognomonic of E. granulosis infection, which is helpful when distinguishing echinococcus cysts from carcinomas, abscesses or haemangiomas. 1he indirect haemagglutination serological test is one of the most sensitive serological tests for the diagnosis of echinococcosis.
Treatment modalities include medical therapy with albendazole, percutaneous aspiration, infusion of scolicidal agents and re-aspiration of cyst content (PAIR) and surgical resection.Treatment is based on considerations of the size, location and manifestations of the cysts, as well as the overall health of the patient.The condition can be prevented by treating and vaccinating animals as well as encouraging basic human hygienic practices.

Conclusion
Although echinococcosis is mainly prevalent in rural areas, patients present at all levels of health care owing to complications of the disease or the lack of a definitive diagnosis.Various radiological modalities SA JOURNAL OF RADIOLOGY • March 2009

Fig. 2 .
Fig. 2. Axial CT scan of the chest.The cystic nature of the pulmonary lesions can be appreciated.

Fig. 3 .
Fig. 3. Coronal CT scan of the abdomen.Three cysts noted in the spleen, as well as a solitary cyst in the inferior region of the liver.