First known case of human bertiellosis in a child in Paraná, Brazil.

Objective: To describe the first known case of human Bertiellosis in Paraná (Brazil).

Case description: A 6-year-old male residing in the Brazilian state of Paraná was suffering from intermittent nonspecific abdominal pain and abdominal distension, associated with expulsion of live tapeworms in his feces for 7 months. He had a history of interaction with monkeys on an island. His first feces analysis was inconclusive, with an initial hypothesis of an atypical Taenia. However, after additional research, the parasitologist identified pregnant proglottids of Bertiella sp. The patient was initially treated with an unknown dosage of albendazole and nitazoxanide, as it was believed he had been infected with Taenia sp. Since the symptoms persisted, praziquantel 10 mg/kg was prescribed without further proglottids elimination.

Comments: Human Bertiellosis is a rare zoonosis, with less than one hundred cases reported. However, it is a cause of chronic abdominal pain and should be kept as a differential diagnosis, especially in cases reporting recurrent tapeworm expulsion in feces and refractory treatment with albendazole.