Case Report: Reemerging Paragonimiasis in Umphang District, Thailand

Abstract

Paragonimiasis is a food-born zoonotic parasitosis caused by Paragonimus spp. Six cases of reemerging paragonimiasis within the Karan hill-tribe near the Thai-Myanmar border were evaluated to review clinical manifestations, predisposing factors, and treatment regimens. All patients tested positive for paragonimiasis eggs and presented with an array of symptoms, including chronic cough, hemoptysis, peripheral eosinophilia, and thoracic radiograph abnormalities. All fully recovered after a 2- to 5-day course of 75 to 80 mg/kg/day praziquantel. We conclude that paragonimiasis should be considered during differential diagnoses to promote early treatment and to prevent misdiagnosis of reemerging or sporadic cases. This applies particularly to endemic regions and high-risk groups known to habitually consume raw or undercooked intermediate or paratenic hosts.

Figure 1.

(A–C) Thoracic radiographs and ultrasound of a 3-year-old Karan boy. (A) The radiograph taken before treatment, with haziness in the right middle lobe (RML) and minimal reticulonodular infiltration in both upper lung fields. (B) The ultrasound, with pericardial effusion 0.68 cm in thickness. (C) The patient’s radiograph 2 weeks after treatment, with markedly decreased pulmonary infiltration. (D and E) Thoracic radiographs of a 4-year-old Karan girl. (D) The radiograph was taken during initial presentation, with reticular infiltration observed in the RML. (E) The effects of treatment after 2 months, with resolution of RML infiltration. (F–H) Thoracic radiographs and computed tomographic (CT) scans for a 10-year-old boy. (F) The CT scan shows hyperdense pleural effusion, with some calcification in the patient’s right lung. The patient’s radiographs before (G) and after (H) treatment illustrate decreased pleural effusion after 7 months. (I and J) Thoracic radiographs of a 55-year-old woman before and after treatment with praziquantel. (I) The radiograph during the hospital visit, with an oval ring-shadow with speckled calcification and nodular infiltration observed in the left hilar region (white arrow). There was no evidence of pleural effusion. (J) The effects of treatment 2 months later, with decreased infiltration within the left hilar region. (K and L) Thoracic radiographs of a 60-year-old man. (K) The radiograph taken during initial presentation, with nodular infiltration in the right upper lobe and lower left lobe. (L) The effects of treatment after 1 month, with partial resolution of pulmonary infiltration. (M and N) Thoracic radiographs of a 66-year-old woman. (M) The radiograph taken during initial presentation, with reticular infiltration in the RML. (N) The effects of treatment after 2 months, with faded infiltration.

Figure 2.

(A) One of seven fresh water mountain crabs (14 cm across) retrieved from around Loy Tong Ku’s waterfall, Umphang District, Tak Province, in December 2017. (B) The metacercarial phase of Paragonimus spp. under a stereomicroscope (×40 magnification). (C) Metacercaria (×40 magnification) of the Paragonimus heterotremus species complex (includes P. heterotremus and Paragonimus pseudoheterotremus).