Can pleuropulmonary paragonimiasis be cured by only the 1st set of chemotherapy? Treatment outcome and clinical features of recently developed pleuropulmonary paragonimiasis.

PURPOSE Most patients with pleuropulmonary paragonimiasis can be cured by the initial single set of Praziquantel (PZQ) treatment. However, several cases have been reported to have unsatisfactory responses to the initial PZQ treatment. The objective of this study was to evaluate the clinical findings of patients with pleuropulmonary paragonimiasis who needed additional PZQ treatment after the 1st set chemotherapy. PATIENTS AND METHODS Thirty-two patients who were diagnosed with pleuropulmonary paragonimiasis at our institution between 2003 and 2008 were retrospectively reviewed. RESULTS All patients were treated initially with PZQ for 3 days (1st set chemotherapy). Twenty-four patients (75.0%) showed improvement in respiratory symptoms and pulmonary involvements. However, eight patients (25.0%) suffered from relapsed respiratory symptoms and pleural effusion. For these patients, an additional 2nd set PZQ treatment resulted in the resolution of the symptoms and pulmonary involvements. The characteristics of patients who needed multi-set treatments were as follows; longer duration of respiratory symptoms (single vs multi-set treatment group; 6.67 ± 8.08 vs 17.86 ± 11.84 weeks, p=0.009), higher IgG titer (optical density, O.D.) for Pargonimus westermani (ELISA O.D. for PW, 0.54 ± 0.19 vs 0.88 ± 0.16 O.D., p=0.001) and higher frequency of multiple pulmonary lesions (% of patients with multiple lesions; 16.7% vs 50.0%, p=0.059). CONCLUSION The patients who had a longer duration of respiratory symptoms, higher ELISA titer for PW and/or multiple pulmonary lesions needed an additional PZQ treatment after the 1st set of chemotherapy. Close follow-up after the initial treatment is necessary especially for such patients.