Snapshot A 15-year-old boy presents to the emergency room for a 2-month history of shortness of breath on exertion and cough. He recently moved from Laos to the United States for school. He reports having an unintentional 8-lb weight loss in the past few months, occasional fevers, and night sweats. He also reports having occasional hemoptysis. Prior to immigrating, he had a normal tuberculin skin test. A chest radiograph shows a linear streak and right-sided consolidation. A sputum sample is procured and sent for microscopy, which demonstrates oval-shaped eggs. (Paragonimiasis) Introduction Introduction flukes are parasitic trematodes characteristics possess 2 suckers (trematos = “pierced with holes”) unsegmented and flattened worms blood fluke Schistosoma species liver fluke Clonorchis sinensis lung fluke Paragonimus species Treatment praziquantel Schistosoma Schistosoma species (blood flukes) organisms Schistosoma haematobium (Africa and Middle East) causes genitourinary tract disease Schistosoma mansoni (Africa and South America) causes intestinal tract and hepatosplenic disease Schistosoma japonicum (East Asia) causes intestinal tract and hepatosplenic disease epidemiology most occur in sub-Saharan Africa transmission snails are intermediate hosts via penetration of skin risk factors exposure to fresh water farming Presentation Katayama fever fevers, hives, weight loss, and cough acute illness after initial infection chronic infections S. mansoni and S. japonicum hepatosplenomegaly with fibrosis and inflammation portal hypertension intestinal tract infection abdominal pain diarrhea S. haematobium squamous cell bladder cancer hematuria (classic symptom) dysuria Studies microscopy of urine or stool S. haematobium eggs with terminal spine S. mansoni and S. japonicum eggs with lateral spine serology or PCR within 2 months of exposure eosinophilia Complications portal hypertension bladder stones squamous cell bladder cancer Clonorchis Clonorchis sinensis (liver flukes) epidemiology east Asia Russia transmission via ingestion of undercooked, dried, or pickled fish pathogenesis causes biliary tract inflammation Presentation chronic symptoms right upper quadrant abdominal pain anorexia weight loss diarrhea jaundice cholecystitis ascending cholangitis cholelithiasis with pigmented gallstones Studies microscopy of stool flask-shaped C. sinensis eggs eosinophilia elevated alkaline phosphatase Complications cholangiocarcinoma Paragonimus Paragonimus species (lung flukes) organisms Paragonimus westermani (east Asia, Africa, and South America) Paragonimus heterotremus (India) transmission via ingestion of undercooked crabs or crayfish pathogenesis inhabits lung parenchyma by penetrating through intestinal wall and peritoneal cavity to diaphragm Presentation tuberculosis-like illness pleural effusion pleuritic chest pain recurrent bacterial pneumonia hemoptysis shortness of breath fever, weight loss, and night sweats Imaging chest radiograph consolidations “ring shadow” of an oval thin-walled cyst linear streak or fluke tract Studies microscopy of sputum or stool ovoid and thick-shelled Paragonimus eggs Complications pulmonary abscess