Molecular and histological identification of the acanthocephalan Bolbosoma cf. capitatum from the human small intestine.

Acanthocephalans of the genus Bolbosoma are intestinal parasites of marine mammals with a lifecycle similar to that of anisakid nematodes. Several cases of Bolbosoma infection in humans have been reported, but no species identification has been made. Here, we report a case of Bolbosoma infection, in which the worm was found in histological sections of the partially resected small intestine of a Japanese man. Morphological features of the worm reconstructed from serial sectioning indicated that the worm was most likely to be a sexually immature female of Bolbosoma capitatum. DNA extraction from paraffin-embedded sections and ITS1-5.8S rRNA-ITS2 sequencing showed that this species formed a monophyletic group with Bolbosoma nipponicum, and was clearly distinguishable from Corynosoma spp. or Polymorphus spp. These results may provide a reference for identifying and characterizing unknown acanthocephalans found in histological sections.

Multiple papules and nodules on the face and neck caused by the larvae of an unknown nematode: A noncreeping type eruption.

Cutaneous larva migrans is caused by various nematodes. Skin manifestations may include superficial or creeping eruptions, folliculitis, and migratory subcutaneous nodules. We report a 52-year-old man with asymptomatic, multiple eruptive papules and nodules on the face and neck caused by the larvae of an unknown nematode. The patient never had any creeping or migratory eruptions. Our case is very unusual and differs from previously reported cases of cutaneous larva migrans.

Small bowel strangulation caused by parasitic peritoneal strand.

A 51-year-old woman with a history of eating raw fish over a period of 2 weeks developed a progressive abdominal pain and leukocytosis with signs of small bowel obstruction. Eosinophilia was not detected in the peripheral blood. The patient underwent surgery to clarify the possibility of ileus. Partial small bowel near the ileum was trapped by a peritoneal strand and was strangulated for approximately 30 cm in length with congestion and edema. The removal of the strand easily released the strangulation and the small bowel returned to a normal appearance. Pathologically, the strand consisted of granulomatous inflammation with a wide zone of necrosis containing a dead ghost feature of a parasite in its center. The necrosis was surrounded by palisading spindle cells with largely lymphocytic infiltration and a few eosinophils. In the parasite, there presented the polymyalian type muscle layer, ventricles and Renette cells, which suggested that the parasite is compatible with the third stage larva of Anisakis type I, leading to the diagnosis of ectopic anisakidosis. It should be noted that, on rare occasions, Anisakis larva migrans can form a peritoneal strand with a wide zone of necrosis and cause strangulation ileus, especially in populations with the habit of eating raw fish.

Pelodera strongyloides infestation presenting as pruritic dermatitis.

Pelodera strongyloides is a free-living soil nematode of the order Rhabditida. We report an 18-year-old man with P strongyloides skin infestation. In this case, pruritic follicular papulopustules developed on the buttocks, then the right flank. Skin scrapings revealed many live rhabditiform larvae that were cultured adult worms and hatched ova, identified as P strongyloides . The eruption was treated effectively with topical 1% gamma-hexachlorocyclohexane ointment.

MORPHOLOGICAL AND TAXONOMICAL STUDIES ON ANISAKIDAE LARVAE FOUND IN MARINE FISHES OF CHINA II. GULF OF TONG KING / 中国寄生虫学与寄生虫病杂志

A survey on Anisakidae larvae in 29 species(134 specimens) of marine fishes in the Gulf of Tong King has been carried out.Anisakidae larvae were detected in 15 out of 29 species.The detected specimens were identified as larvae of Anisakis simplex,Hysterothylacium and Pseudoterranova.The parasitization rate of Anisakis simplex larvae,the main pathogen of anisakiasis,in fishes was 30.6% (41/134),while the parasitization rates of Hysterothylacium and Pseudoterranova larvae were comparatively low.Hysterothylacium larvae China type I detected from Muraenesox clnereus and Trichiurus Tiaumela was a new record.Their morphological characteristics were summarized as follows: 1.Length 10.78-14.18mm,Width 0.25-0.38mm,the length of the esophagus is 1.14-1.73mm,intestinal cecum 0.77-1.24mm and ventricular appendage 6.27-8.40mm,extending parallelly with the intestine to the last quarter of the larva; 2.Boring tooth was present,but mucron was absent; 3.No genital anlage was observed.