A 48-year-old man referred with pain and swelling at the upper and middle third of left tibia with a history of previous osseous HYDATID DISEASE three years ago. Despite surgical procedure which was performed in this case, recurrence was observed and repeated exploration with wide resection and oral medical therapy were recommended. Bone HYDATID cyst is an uncommon DISEASE with difficult response to treatment. HYDATID DISEASE should be included in the differential diagnosis of cystic lesions of bone in endemic regions.

Perhaps no other bone infection is more difficult to eradicate, as bone echinococcosis. Unfortunately, despite of several years experience in this regard, we still have not found the solution to this zoonotic infection of bone. Every year, several affected people are visited by many orthopedic surgeons and infectious DISEASE specialists all over the country and in referral hospitals and eventually, the skillful neglect seems to be selected as a last resort by most of these visiting physicians. So here remains an important question to be answered: why are we unable to eradicate bone HYDATIDosis in spite of improvement in our techniques for diagnosis, assessment of the extent of involvement by radiological studies, medical management with new chemotherapeutic agents and surgical resection of the cysts?

Alvelolar HYDATID DISEASE is caused by E. multilocularis. Human infection occurs at the larval stage of this small tape worm (1.2 to 4.5 mm). In this article we studied alveolar HYDATID DISEASE in a 50 year old woman who presented with a hepatic mass. Liver biopsy and histopathologic evaluation showed alvelolar HYDATIDosis of the liver. Then resection of the left lobe of liver was done, with medical treatment with oral Albendazole (15 mg/kg/12h) for 6 weeks with 2 week intervals. The drug was continued for 4 courses. 5 year follow up of the patient was satisfactory without any complaint.

A 45-year-old housewife was referred to our center with a two-week history of moderate to severe pain and fullness of the epigastric and left upper quadrant area. She had no history of fever, jaundice, abdominal trauma, weight loss, or other symptoms. She gave a history of epigastric fullness and dyspepsia of one year duration, for which she was taking ranitidine on demand. Physical examination was normal except for the presence of a large, smooth, and nontender mass in the epigastric area extending to the left upper quadrant. Paraclinical investigations, including a complete blood count, liver and kidney function tests, serum lipase, blood chemistry, CA19-9, CEA, urinalysis, and stool examination for ova, parasites, and occult blood were reported normal except for an erythro­cyte sedimentation rate of 50 mm after the first hour and a serum amylase of 300 IU/dL. Chest X-ray was normal. Abdominal ultrasonography revealed a large cystic mass measuring about 15 cm in diameter compatible with a large pseudocyst of the pancreas. An abdominal computerized tomography (CT) scan was taken (Figure 1).      

There are three main differences between HYDATID cysts of the lung and those of the liver. All three are readily explained on the basis of anatomic difference between these two organs: 1. The liver is involved about five times more often than the lungs. The reason is that the majorio/ of ingested hexacanth embryos of the parasite, Echinococcus granulosus, about 30 microns in diameter, is carried to the liver 'in the portal system. There they are filtered out in liver sinusoids. No more than about 20% of these ova manage to escape the adult human liver to become trapped in the pulmonary capillaries.

HYDATIDosis usually is seen in lung and liver in human. Involvement of the breast by hydatic cyst is rare. A 26 years old woman referred to our clinic due to a palpable mass in her right breast. In ultrasonography a cystic lesion was seen. In mammography an opaque well defined lesion with a thin calcified margin was seen in her right inferomedial maxillary zone with 3 and 4 cm diameters without breast tissue destruction or microcalcification. Diagnosis of hydatic cyst was suggested and confined by pathology.Hydatic DISEASE of the breast is rare. However, it might constitute a potentially serious differential diagnosis of a breast lump in areas endemic for this DISEASE.