Diphyllobothrium latum Mimicking Subacute Appendicitis

Abstract

Diphyllobothrium latum (D. latum) infection in humans is uncommon in the United States. Although there has been a drastic decline in the report of D. latum infection in this region, physicians should be aware of an uncommon presentation and its clinical relevance. We report a case of 55-year-old female of Ecuadorian/Peruvian origin who presented with an unknown cause of chronic right lower quadrant abdominal pain for 2 months without other particular symptoms. Initial workup revealed evidence of iron deficiency anemia, and stool occult blood test was positive. She was scheduled for a colonoscopy to assess the source of occult gastrointestinal bleeding. During her bowel preparation, she passed a 25 cm long white tapeworm-like material confirmed microscopically. Despite passing a worm she continued to have abdominal pain. During the colonoscopy, another worm was found lodged in the appendiceal orifice. The colonoscopic images revealed a segmented tapeworm showing contractile motility, approximately 12 cm in length and 6 mm wide in the appendiceal orifice. The scope was unsuccessful in removing the worm. The parasitological and microbiological examination of the passed worm was positive for D. latum. D. latum a fish tapeworm that infects humans after the ingestion of raw or undercooked fish. The patient had a history of often eating lightly marinated raw fish (“ceviche”) in Peru several months before presentation. It is uncommon for D. latum infection to present with iron deficiency anemia. As the worm absorbs approximately 80% of dietary vitamin B12, prolonged D. latum infection usually causes vitamin B12 deficiency and megaloblastic anemia, which is reported to affect about 40% of cases. Abdominal pain related to mechanical obstruction is reported, but this case is unique in that the worm preferentially attached to the appendiceal orifice causing subacute focal appendiceal pain. She was treated with a single dose of oral praziquantel. After the treatment, she developed minor cramping for the next 2 days which resolved by day 3, and recalled passing half-inch sized pieces of white tissue and subsequently improved. Although D. latum infection is an uncommon cause of chronic abdominal pain with iron deficiency anemia, it is crucial to consider because of the potentially treatable outcome.

Diphyllobothriasis Caused by the Sanada Tapeworm: A Case Report

“…In our case, the consideration of sushi as the source of infection, the asymptomatic nature of the patient, and the detection of the infection due to the expulsion of the parasite from the anus were similar to the presentation in other typical cases of diphyllobothriasis. Although atypical cases, manifesting aberrant migration of proglottids or massive infection, can cause cholecystitis, cholangitis, intestinal obstruction, or vitamin B12 deficiency [ 11 , 14 ], such serious complications did not occur in our case, which could be partly attributed to the high possibility of Dibothriocephalus nihonkaiense infection, early diagnosis and treatment, and good response to treatment.…”

Diphyllobotrium Spp. como causa de diarrea crónica diagnosticada solo por colonoscopia o cápsula endoscópica

“…tienen niveles bajos de vitamina B12, y pueden desarrollar anemia megaloblástica, debido a que el 80% de la ingesta diaria de vitamina B12 es absorbida por los parásitos. (2) Actualmente, los exámenes de heces son el gold standard para detectar infecciones por helmintos. Sin embargo, los exámenes de heces tienen baja sensibilidad para detectar a Diphyllobotrium spp., tanto en su forma adulta, huevos o proglótidos; en un examen microscópico de heces directo con concentración previa es 38% (rango 3.9-52.5%) (3,4) No es raro, al revisar la literatura, reportes de casos en países tropicales y subdesarrollados donde se diagnostican de manera casual, diversos parásitos (diphyllobotrium, tenias, ascaris, uncinarias, entre otros) al momento de realizar una endoscopía, colonoscopía o cápsula endoscópica, como parte del estudio de otras patologías.…”

“…Sin embargo, los exámenes de heces tienen baja sensibilidad para detectar a Diphyllobotrium spp., tanto en su forma adulta, huevos o proglótidos; en un examen microscópico de heces directo con concentración previa es 38% (rango 3.9-52.5%) (3,4) No es raro, al revisar la literatura, reportes de casos en países tropicales y subdesarrollados donde se diagnostican de manera casual, diversos parásitos (diphyllobotrium, tenias, ascaris, uncinarias, entre otros) al momento de realizar una endoscopía, colonoscopía o cápsula endoscópica, como parte del estudio de otras patologías. (5)(6)(7)(8) Nuestros dos pacientes presentaron diarrea crónica sin moco, sin sangre, con componente nocturno, asociadas a dolor abdominal y baja de peso. Ambos habían sido visto por varios gastroenterólogos sin diagnóstico y tenían en los exámenes auxiliares, dos seriados de tres muestras cada uno de heces con resultados negativos, y discreto patrón inflamatorio con PCR y Calprotectina fecal levemente alta, sin leucocitosis, ni eosinofilia.…”

Domestication and microbiome succession may drive pathogen spillover

“…There is published evidence that many bacteria in the human gut produce essential vitamins like B12 (Degnan et al, 2014). There are human intestinal worms that make use of the products of the gut-colonising microbiota and take up these vitamins causing B12 deficiency-related diseases in the human host (Sharma et al, 2018). Microbiome succession.…”