Epidemiology and clinical features of cystic hydatidosis in Western Sicily: a ten-year review

Abstract

Aim: To assess retrospectively the epidemiological and clinical aspects of cystic echinococcosis (CE) and to evaluate follow-up and response to treatment in patients affected by CE.

Methods: From January 2000 to December 2010, all patients affected by CE at the Infectious Diseases Units of the University of Catania and of Basilotta Hospital in Nicosia-Enna, were enrolled as participants in the study. Epidemiological, clinical and laboratory data were collected for each patient. Diagnosis of CE was performed using clinical imaging and laboratory parameters. Response to treatment was categorized as follows: "cure" as the disappearance or complete calcification of cyst/s; "improvement" as a reduction in the diameter and/or number of existing cysts; and "impairment" as an increase in the diameter and/or number of existing cyst/s and the onset of relapses (i.e., the onset of new cyst/s and an increase in the diameter of previously existing cyst/s and/or complications. Immunoglobulin E (IgE) titers and eosinophil percentages were evaluated at diagnosis, at six months after the initiation of treatment and again in the case of relapse. Hyper-eosinophilia was defined as an eosinophil percentage of ≥ 6%.

Results: Thirty-two patients were diagnosed with CE in our Unit during the research period, with a male-female ratio of 2:1. At the time of diagnosis, 40% of patients presented a single CE cyst. Sixty percent showed multi-organ involvement. The liver-lung localization ratio was 2:1. Patients below the age of 50 at diagnosis were more likely to have multiple cysts (73.7% vs 35.5%, P < 0.05). Regarding treatment, 30 patients were treated medically and 16 surgically. Fourteen patients were treated both medically and surgically. Relapses were seen to be less frequent in patients treated with albendazole before and after surgery. Complete cure or an improvement was achieved in 23 patients. Impairment was observed in one patient. Two patients showed no improvement. Relapses were more frequent in those patients treated before 2005. At diagnosis, 71% of patients were positive for specific CE IgE, and 56.3% showed an eosinophil percentage of ≥ 6%. Patients who were diagnosed with hyper-eosinophilia developed complications more frequently than the other patients, but did not suffer relapses.

Conclusion: On the basis of our results, we propose cystic echinococcosis screening for family members of patients, appropriate pre- and post-surgery treatment and the assessment of anti-echinococcus IgE titer or eosinophil percentage as a therapy response marker in settings with limited resources.

Keywords: Cestode infections; Cystic echinococcosis; Diagnosis; Epidemiology; Hydatid disease.

Figure 1

Correlation between different groups. A: Correlation between exposure of patients to risk factors and presence of relatives affected by cystic echinococcosis (CE); B: Correlation between age at diagnosis and presence of single or multiple CE; C: Correlation between cysts location and presence of symptomatic CE; D: Correlation between treatment modality and development of relapses; E: Correlation between rate of eosinophils at diagnosis and development of complications. ^aP < 0.05, ^bP < 0.01 vs control group.