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P Prociv

Publications and source records attributed to P Prociv.

At least 55 records · Page 3Linked to original sources
PubMed1994

Occult enteric infection by Ancylostoma caninum: a previously unrecognized zoonosis.

BACKGROUND/AIMS: Human disease caused by the canine hookworm Ancylostoma caninum and a high incidence of eosinophilic enteritis have been reported from northern Queensland, Australia. The aim of this study was to evaluate patients with unexplained abdominal pain and a possible association with cryptic infections by A. caninum. METHODS: The clinical and demographic features of patients from this region with eosinophilic enteritis (group A1, n = 42), obscure abdominal pain associated with (group A2, n = 105) and without (group A3, n = 84) blood eosinophilia were reviewed and sera were tested against A. caninum excretory-secretory antigens by enzyme-linked immunosorbent assay (ELISA) and Western blot. Four additional patients, two with confirmed A. caninum, had hookworm infection. RESULTS: The level of dog ownership in these four groups was 79%-100%, higher than in the local population (P < 0.001). The ELISA tested positive in 71% of A1, 67% of A2, and 30% of A3, versus 8% in controls (P < 0.002). All cases tested were positive on Western blot versus 10% of controls (P < 0.0001). The ELISA values increased with chronicity and decreased during convalescence. CONCLUSIONS: We conclude occult human A. caninum infections are common and are characterized by eosinophilic enteritis and obscure abdominal pain with or without blood eosinophilia. The diagnosis can be confirmed by serology.

Adolescent↗
PubMed1994

Immunologic incrimination of Ancylostoma caninum as a human enteric pathogen.

In northeastern Australia, the incidence of human eosinophilic enteritis (EE) and unexplained abdominal pain with peripheral blood eosinophilia (PE) appear to be exceptionally high. Because adults of the common dog hookworm, Ancylostoma caninum, were found in situ in several cases, we compared specific antibody responses in patients with EE or PE with those of individuals from various control groups. Sera were obtained from three patients with confirmed dog hookworm infection, 25 patients with EE/PE, 42 with other diagnosed gastrointestinal disorders, eight with human hookworm infection, 27 with other diagnosed parasitic infections, and 100 blood donors from the State of Tasmania, where A. caninum does not occur. They were analyzed by enzyme-linked immunosorbent assay (ELISA) and Western blot for IgG and IgE antibodies to excretory-secretory (ES) antigens from adult A. caninum. In the ELISA, sera from 88% of EE/PE patients were positive for IgG and IgE antibodies to ES antigen. All eight patients infected with human hookworm (identified as A. duodenale in three) were also seropositive, while most of those with other parasitic infections, as well the blood donors, those with diagnosed gastrointestinal diseases, and the control subjects, were seronegative. In Western blots, sera from 92% of EE/PE patients demonstrated IgG and IgE antibodies to a component of ES antigen with a molecular weight of approximately 68 kD (Ac68), as did all sera from cases infected with human hookworms. Among the patients with other gastrointestinal disorders and parasitic infections, four of 42 (10%) and three of 27 (11%), respectively, reacted positively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

Secretion of cysteine proteinase activity by the zoonotic hookworm Ancylostoma caninum.

The zoonotic hookworm, Ancylostoma caninum, probably induces human eosinophilic enteritis by inducing allergic responses to its secretions. This species is already known to secrete metalloproteinases, but in other parasites, cysteine proteinases are involved in pathogenesis. We studied somatic extracts of A. caninum adults and infective larvae and adult excretory/secretory (ES) antigens for cysteine proteinase activity using fluorogenic peptide substrates and by gelatin and fluorogenic substrate polyacrylamide gel electrophoresis. Proteolytic activity was observed against the cathepsins L and B-specific substrate Z-phe-arg-AMC, against the plasmin substrate Boc-val-leu-lys-AMC, and against gelatin. The Z-phe-arg-AMC-hydrolyzing activity in ES antigens and in adult extracts was enhanced up to 15-fold by the reducing agent dithiothreitol (DTT), but was totally blocked by specific inhibitors of cysteine proteinases, including the peptidyl diazomethyl ketone Z-phe-ala-CHN2,E-64, leupeptin, and N-ethylmaleimide. In a similar fashion, gelatinolytic activity in ES antigens detected using substrate gels was enhanced by the addition of reducing agents and inhibited by Z-phe-ala-CHN2 and E-64. The DTT-enhanced, Z-phe-arg-AMC-hydrolyzing activity in ES antigens was active over a wide pH range (pH 5-9). Similar cysteine proteinase activity to that detected in ES antigens was present in extracts of adult and infective larvae of A. caninum. Because the substrate Z-phe-arg-AMC was specifically hydrolyzed, and because this hydrolysis was totally blocked by cysteine proteinase-specific inhibitors, ES antigens and tissue extracts of A. caninum clearly possess cysteine proteinase activity.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1993

Observations on strongyloidiasis in Queensland aboriginal communities.

OBJECTIVE: To report the prevalence and distribution of infections with the parasitic nematode Strongyloides stercoralis in the Aboriginal and Torres Strait Islander communities of Queensland. DESIGN: A 20-year retrospective survey of computerised data and selected files from the former Aboriginal Health Programme (AHP) of the State Health Department of Queensland, based on cases diagnosed by the microscopic examination of preserved faecal specimens. Findings were compared with figures published in annual reports. STUDY POPULATION: Children under 15 years of age from 122 Aboriginal and Torres Strait Islander communities. RESULTS: Numbers of specimens examined varied widely according to time and place, as did detected infection rates. In 32,145 faecal samples examined by AHP microscopists during 1972-1991 the overall infection prevalence was 1.97%. Strongyloides larvae were found in only 52 of 122 communities. The parasite was absent from many small, southern inland communities, and the prevalence of infection increased in northern regions with summer wet seasons. On average, it was highest in Doomadgee (12%), where a peak prevalence of 27.5% (92/334 children examined) was detected in a wet season survey. Some infections resolved spontaneously, while others persisted for more than four years. At Gununa (Mornington Island), the prevalence fell from 26.2% to below 7% after thiabendazole treatment of most infected children, and remained at this level for at least four years. Single stool examinations by experienced microscopists may have failed to diagnose at least 26% of infected cases. The records give no indication of the clinical impact of strongyloidiasis. CONCLUSIONS: Strongyloidiasis is well established in many Aboriginal communities of north-eastern Australia. Children appear to be the major reservoirs of infection; the prevalence in adults is probably much lower. Failing improvements in community sanitation and hygiene, it may be possible to reduce significantly, if not eradicate, the infection by selectively treating diagnosed children with thiabendazole.

Adolescent↗
PubMed1993

Verminous asthma.

Explore the source record for details and available documents.

Ascariasis↗
PubMed1993

In vitro embryonation of Syphacia obvelata eggs.

Mouse infections with the pinworm, Syphacia obvelata, were evaluated as a potential model of human enterobiasis. Eggs of S. obvelata were found to be much less resistant to adverse environmental factors than those of Enterobius vermicularis, perishing rapidly when exposed to desiccation or to water. The average number of eggs produced by a female worm was 317 +/- 29 S.D. (range: 266-347), which is about 2-3% of the fecundity of E. vermicularis. Eggs expressed from gravid S. obvelata were incubated under various conditions, but the only reliable method of supporting complete embryonation was culture on a floating cellophane membrane. At 30 degrees C on this substrate, eggs were found to be infective between 6 and 42 h, inclusive. The pre-patent period in mice fed these eggs was 11-15 days. The more fastidious developmental and survival requirements of Syphacia eggs indicate that transmission of this species depends on much more intimate contact between hosts than is required by E. vermicularis.

Animals↗
PubMed1992

Successful treatment of disseminated strongyloidiasis.

OBJECTIVE: To report the successful treatment of Strongyloides stercoralis hyperinfection, which is usually lethal but in this case was diagnosed in its early stages. CLINICAL FEATURES: A 44-year-old woman, who had spent much of her life in Fiji and India, was treated with a high dose of prednisolone for rheumatoid arthritis complicated by gold lung. The onset of abdominal symptoms, an exacerbation of respiratory symptoms, and a persistent high eosinophil count and serum IgE level, led to the detection of numerous Strongyloides larvae in her faeces and sputum. INTERVENTION AND OUTCOME: She was treated with thiabendazole for five days, then mebendazole for one month, and the dose of prednisolone was reduced. Clinical symptoms and signs improved within days and after one week parasites could not be found in her faeces. After six months, enzyme-linked immunosorbent assay for Strongyloides infection gave a reading which was 40% of the initial level but still in the positive range. CONCLUSION: Steroid therapy in individuals with chronic, subclinical strongyloidiasis predisposes to the insidious development of hyperinfection syndrome, which has a high mortality rate. If detected early, this complication can be treated effectively. It can be prevented by actively seeking Strongyloides infection, by faecal microscopy and culture techniques and by serological tests, in high-risk individuals, such as immigrants from endemic areas.

Adult↗
PubMed1992

Human ectopic fascioliasis in Australia: first case reports.

OBJECTIVE: To describe the manifestations of two cases of migratory ectopic fascioliasis diagnosed in Australia, including the first report of lymphatic infection. PRESENTATION: Both patients presented with acute, superficial swellings. In the first, a 46-year-old woman, the lump was found to be a cervical lymph node containing a mature Fasciola hepatica which had released eggs into surrounding tissues. The second patient was a 34-year-old male abattoir worker, in whom the subcutaneous lesion resembled an infected sebaceous cyst and contained an immature fluke. FINDINGS: Both lesions were resected and diagnosed histologically. Fasciola eggs were not found in the faeces of either patient. Blood eosinophilia was not detected in either case. A serological test for fascioliasis was carried out in the second case and the result was positive. In both cases, infection was probably acquired in Australia, although neither patient had eaten watercress. OUTCOME: Neither patient was specifically treated with anthelminthic agents, and neither suffered further complications. CONCLUSION: Migratory fascioliasis occurs in Australia. It can present as superficial or deep focal lesions, not necessarily in association with peripheral blood eosinophilia or Fasciola eggs in faeces. Serological tests may be helpful in diagnosing such cases.

Adult↗
PubMed1992

Isosporiasis in the aboriginal population of Queensland.

OBJECTIVE: To report on the endemicity of Isospora belli in Queensland. DESIGN: A 10-year retrospective survey of data from routine parasitological surveillance of Queensland Aboriginal communities, by microscopic examination of preserved faecal specimens. SETTING: The Aboriginal Health Programme of the Queensland Department of Health and Medical Services. POPULATION: Children under 15 years of age from all the Aboriginal communities of Queensland. RESULTS: Oocysts of I. belli were detected in 33 (0.2%) of a total of 17,642 faecal samples examined. CONCLUSION: Isosporiasis is endemic in the Queensland Aboriginal population. It is likely to be more common than indicated, because the infection is difficult to diagnose, and the techniques used to identify the organism were not particularly sensitive. It is predicted that isosporiasis will be recognised with increasing frequency as a cause of diarrhoea in Aboriginal and white Australians who develop AIDS.

Adolescent↗
PubMed1992

A genetic comparison of human and wildlife isolates of Echinococcus granulosus in Queensland: public health implications.

OBJECTIVE: To test the hypothesis that the hydatid parasite infecting macropods and dingoes in Queensland is a sylvatic strain of Echinococcus granulosus, distinct from the domestic strain which produces cysts in sheep and humans. DESIGN: Molecular biological techniques were used to compare DNA isolated from hydatid cysts from humans, local macropods and sheep from New South Wales and the United Kingdom, as well as from adult tapeworms in dingoes. SETTING: The human cysts were surgically resected from two patients seen with hydatidosis in Brisbane teaching hospitals over a one-year period. Neither patient had had previous contact with sheep farms. Macropods and dingoes were shot randomly in the localities where the patients presumably acquired their infections. Sheep liver cysts were obtained from abattoirs. METHODOLOGY: Studies comprised extraction of DNA from cysts, digestion by a series of restriction endonucleases, slab gel electrophoresis. Southern blotting and then hybridisation with defined DNA probes. Polymerase chain reaction, in combination with direct DNA sequencing, was used to compare DNA from cysts and adult worms from dingoes. RESULTS: The restriction fragment length polymorphism (RFLP) patterns of DNA from all cysts and a defined mitochondrial DNA sequence from all sources were indistinguishable. This finding is significant as both techniques can clearly distinguish between genetically distinct, well characterised strains of E. granulosus. CONCLUSIONS: Hydatid cysts are prevalent in some macropod populations and adult worms are common in dingoes. Since there are relatively few sheep-rearing areas in Queensland, contact with wild animals may be the main source of human hydatid infection in this State. The strain of E. granulosus in both patients was genetically indistinguishable from that found in macropods, dingoes and sheep from New South Wales and the United Kingdom. This strongly suggests that the domestic strain of E. granulosus, or a form very close genetically, freely infects Australian wildlife, and argues against the existence of a distinct sylvatic strain. The implications for public health are considerable.

Adult↗
PubMed1992

Strongyloidiasis in North Queensland: re-emergence of a forgotten risk group?

OBJECTIVE: To describe the clinical presentation, diagnosis and management of strongyloidiasis in northern Queensland, and to identify predisposing factors for this infection. DESIGN: A five-year retrospective study of medical records of all cases diagnosed in a regional hospital microbiology laboratory, with follow-up by interview where possible. SETTING: The Townsville General Hospital. PATIENTS: A total of 14 cases of strongyloidiasis were identified, with patients ranging in age from 7 months to 59 years. RESULTS: Infected patients included nine Aborigines and two Vietnamese refugees, both high-risk groups. Of three Caucasians diagnosed, one was a war veteran, but the other two did not have significant travel histories; all three had lived or worked under insanitary conditions. In only one case was strongyloidiasis suspected; in most, it was diagnosed because of diarrhoea or blood eosinophilia which could not be related to the presenting illness. Thiabendazole treatment was effective in most cases. CONCLUSION: In northern Australia, strongyloidiasis can be acquired locally by Caucasians who live in unhygienic circumstances. It should be suspected in any person with unexplained abdominal pain, diarrhoea, cutaneous symptoms or blood eosinophilia, and the laboratory must be informed of the provisional diagnosis.

Adolescent↗