Disseminated peritoneal Schistosoma japonicum: a case report and review of the pathological manifestations of the helminth

Schistosomiasis [also known as bilharzia, bilharziasis, bilharziosis or snail fever] is a human disease syndrome caused by infection from one of several species of parasitic trematodes of the genus Schistosoma. The three main species infecting humans are S haematobium, S japonicum, and S mansoni. S japonicum is most common in the fareast, mostly in China and the Philippines. We present an unusual case of S japonicum in a 32-year-old Filipino woman who had schistosomal ova studding the peritoneal cavity and forming a mass in the right iliac fossa

Novel real-time PCr for detection of Schistosoma japonicum in stool.

Chemotherapy has been used on a large scale in countries where the blood fluke Schistosoma japonicum is endemic. This has led to a lower intensity of infections and consequently lower diagnostic values of commonly used diagnostic tests like serology and Kato-Katz stool smear. We designed a novel real-time PCR method for detection of S. japonicum in stool samples. Further, we evaluated different versions of an inexpensive, non-commercial extraction method, ROSE, as well as the commercial QIAamp DNA Stool Mini Kit. PCR primer sequences were designed targeting the mitochondrial NADH dehydrogenase I gene. Bovine serum albumin was added to the DNA extracts and SYBR Green was used for detection. The PCR method was evaluated with non-infected stool samples spiked with S. japonicum eggs. It demonstrated high sensitivity, even in samples containing a single egg. The two extraction methods were equally effective. The PCR was specific for S. japonicum when tested against other Schistosoma species, Trichuris trichiura, hookworm and Taenia sp. We conclude that this novel real-time PCR, in combination with either ROSE or QIAamp DNA Stool Mini Kit extraction, is a sensitive and specific tool for diagnosing S. japonicum in human stool samples.

Sensitive enzyme-linked immunosorbent assay with urine samples: a tool for surveillance of schistosomiasis japonica.

An enzyme-linked immunosorbent assay (ELISA) to detect antibodies to Schistosoma japonicum soluble egg antigens (SEA) in un-concentrated urine was developed. The urine ELISA was applied to samples collected in a schistosomiasis-endemic village in China. The levels of anti-SEA antibodies detected in urine correlated well with those obtained with paired serum samples (r = 0.694, p<0.0001). Among 129 serum ELISA positives, 112 (86.8%) were positive by urine ELISA, while all 40 serum ELISA negatives from a non-endemic area were negative. The levels of anti-SEA in urine samples were stable up to 8 weeks of storage at 37 degrees C, with sodium azide as a preservative. Therefore, ELISA with urine samples can be used for the surveillance of schistosomiasis.

The serological differentiation of acute and chronic schistosomiasis japonica using IgA antibody to egg antigen

Two groups of Schistosoma japonicum infected patients (acute and chronic) and non-infected individuals were studied using IgA antibody to egg antigen (SEA) and IgG and IgM antibodies to keyhole limpet haemocyanin (KLH). The means and standard deviation of the optical density in ELISA of acute, chronic and negative groups for IgA anti-SEA were 583ñ124.7, 98.2ñ78.8 and 82.2ñ39.3, respctively. There was a statistically significance between acute patients and chronic patients (P<0.01). The means and standard deviation of IgG and IgM antibodies to KLH were 501.5ñ150.6, 113.0ñ79.1, 28.8ñ56.3 and 413.6ñ148.5, 70.2ñ14.8, 65.3ñ45.3, repectively. The detection results of IgA to SEA compared with the IgG and IgM to KLH did not demonstrate a significant difference (P>0.01). The sensitivities of IgA to SEA and IgG and IgM antibodies to KLH for the detection of acute infection were 95.24 per cent, 90.48 per cent and 85.71 per cent respectively. Therefore, this study showed that the detection of IgA to SEA is also a useful new method for the serological differentiation of acute and chronic schistosomiasis japonica in humans.

The possibility of GST antigen from Chinese strain of Schistosoma japonicum for immunodiagnosis of schistosomiasis.

The GST antigen (called 26-28 kDa antigen) extracted and purified from Schistosoma japonicum adult worms was applied to the detection of specific antibodies in sera of infected mice and mice immunized with the above protein antigen by ELISA technique. The 26-28 kDa antigen was better than crude antigens (SEA, SWAP) when used to detect specific antibodies in sera from immunized mice. As with crude antigens (SEA and SWAP), the 26-28 kDa antigen could be used to detect specific antibodies in infected sera, with titers as high as 1:160-1:320. There were no false positive reactions and a positivity rate as high as that using SWAP occurred when the 26-28 kDa antigen was used in schistosomiasis patients and normal subjects by intradermal test. It is suggested that the 26-28 kDa antigen may be a suitable candidate for immunodiagnosis of schistosomiasis.

Schistosoma japonicum-like infection in Phichit province, northern Thailand: a case report.

A case of human schistosomiasis from Phichit Province is presented. Schistosome eggs were found in the ileo-caecal mass of a 44-year old woman, native of Sak-Lek, Muang District. Histologic pictures revealed an early acute granulomatous lesion which consisted of predominantly eosinophils without multinucleated giant cells and fibrotic change suggesting a recent infection. On the basis of the shape and microscopic appearance of the eggs, they are smaller than those described previously for Schistosoma japonicum, probably those of S. mekongi, a related species. This is the third histologic-confirmed case of schistosomiasis in this locality. Addendum: At the time of the manuscript preparation, another case of schistosomiasis was diagnosed. A 55-year old man who lives entirely in the very close adjacent village to the present case was admitted to the Ramathibodi Hospital, Bangkok with chronic hepatosplenomegaly in January 1986. Amyloidosis was suspected and rectal biopsy revealed schistosome eggs, some contained miracidia with varying degrees of degeneration, some were empty and/or fragmented shells and were surrounded with fibrotic changes and chronic cellular infiltration (Fig. 5). They were identical to those of Schistosoma japonicum. Several fecal examinations, miracidium hatching and COPT yielded negative results. This finding showed significantly that all schistosomiasis cases reported from this locality, except the second one, were in the old age group of 40 and above. Further epidemiologic investigation is in progress to delineate this locality as a potential endemic area for this infection.