Background: Multiple intracranial hydatidosis (MIH) is a rare disease, with serious neurological manifestations, high recurrence and a mortality rate comparable sometimes to malignant disease. The causes of multiple infestations and their mechanisms are not clearly understood. Several attempts at classification are reported in the literature, but the diversity in location of these cysts in the brain and other organs, their appearance and recurrence rates remain largely unexplainable.
Objective: Multiple intracranial hydatidosis (MIH) is reported in a series of patients to evaluate their incidence, localization, complications treatment and recurrences. In this study we tried to explain the mechanism of multiple infestations, and to propose a new classification.
Methods: This was a retrospective study of thirty-four patients with MIH, treated between 1976 and 1999. The diagnosis was made mainly by CT scan and confirmed by surgery. MIH following iatrogenic rupture of a solitary cyst in the brain was excluded. Hydatid cysts were removed by the method described by Arana-Iñiguez (1973) using Dowling's technique. Histopathological examination was used to confirm the presence of scolices. The patients were followed-up for 3-14 years.
Results: Twenty six patients (76.4%) were under the age of 20 years with a male to female ratio of 1.0:1.83. Clinically, patients with cysts exhibited features of increased intracranial pressure and focal neurological deficit. The cysts had a diameter between 2 to 120 millimeters. Histopathological examination showed that 63.6% of the cysts were fertile. Eleven patients (46.4%) achieved a good outcome. The operative mortality rate was 10.7%. Overall mortality was 17.6%. Five patients had more than one recurrence, which appeared after 3 months to 3 years.
Conclusion: MIH are rare; to date only 77 reported cases have been encountered. To have such a high incidence in Iraq raises the possibility of a different strain of Echinococcus granulosis. A suggestion is made regarding terminology and classification.