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A M Polderman

Publications and source records attributed to A M Polderman.

120 records · Page 7Linked to original sources

Haematobium schistosomiasis among seminomadic and agricultural Afar in Ethiopia.

Parasitological and malacological surveys were made in the Afar tribal area on the flood plains of the Awash River. S. haematobium--infections are most prevalent among seminomadic Afar living around the swamps and lakes in the middle part of the Awash Valley. Infection rates between 6 and 52% were found among seminomadic Afar and between 0 and 27% in agricultural groups. The highly localised distribution of vesical schistosomiasis is maintained by the distribution of the swamps, lakes and the human population and by migration patterns. On the marshy plain near Gewani significantly higher infection rates occur among Afar females than males. This is apparently due to sex differences in water contact patterns.

Adolescent↗

Treatment failure in trichomoniasis and persistence of the parasite after Lactobacillus immunotherapy; two case reports.

This report describes the clinical and laboratory observations on two patients with a Trichomonas vaginalis infection resistant to metronidazole. The metronidazole resistance was confirmed in in vitro cultures under aerobic conditions, after in vitro cultivation of the strains. Trichomonas infection persisted during high-dose intravenous metronidazole administration and Lactobacillus immunotherapy was unsuccessful in both patients.

Adult↗

Circulating anodic antigen levels in serum before and after chemotherapy with praziquantel in schistosomiasis mansoni.

The kinetics of serum levels of circulating anodic antigen (CAA) of Schistosoma mansoni were studied in patients with intestinal schistosomiasis before and after treatment with praziquantel. Day to day fluctuation in faecal egg excretion was compared with fluctuation in antigen level in 20 patients by serum and stool examination on 3 consecutive days before treatment. Antigen levels - calculated either as absorbance value of undiluted serum or as titre - showed less fluctuation than the number of eggs per gram of faeces determined by stool examinations based on single or duplicate 25 mg Kato smears. Compared with a placebo control group of 11 individuals, there was a significant reduction in CAA level in serum of 10 patients treated with praziquantel (40 mg/kg), 10 weeks after treatment. A similar decrease in serum CAA level was observed in a group of 46 patients treated with praziquantel, 6 weeks after treatment. In both groups, patients who remained seropositive after treatment still excreted eggs in their faeces. The kinetics of the antigen decrease were studied in more detail in 20 patients in hospital. Within 10 d after treatment with a double dose of 40 mg praziquantel per kg body weight, the antigen level fell to less than 10% of the original serum level, with a CAA half-life of approximately 2 d.

Animals↗

Serological diagnosis of Oesophagostomum infections.

A sensitive and specific enzyme-linked immunosorbent assay (ELISA) is described to diagnose human infection with Oesophagostomum bifurcum. In an ELISA using crude soluble antigen, prepared from adult O. bifurcum, many cross reactions occurred when measuring IgG titres in patients with other helminth infections. An ELISA based on the detection of specific IgG4, however, had a specificity of over 95%. The sensitivity of the IgG4 ELISA was difficult to assess because a reliable parasitological diagnosis is not available. The IgG4-ELISA described seems to be a powerful new tool to study the distribution of this little known but locally very common nematode parasite.

Adolescent↗

Treatment of mixed Oesophagostomum and hookworm infection: effect of albendazole, pyrantel pamoate, levamisole and thiabendazole.

Oesophagostomum bifurcum has recently been recognized as a common parasite of man in northern Togo and in Ghana. In a preliminary trial several anthelmintics were evaluated in the treatment of mixed Oesophagostomum and hookworm infections. Diagnosis was based on faecal culture, since the eggs of Oesophagostomum and hookworm cannot be distinguished morphologically. Of the anthelmintics tested, albendazole was most effective against both parasites. Pyrantel pamoate, 2 x 10 mg/kg, was effective against Oesophagostomum but not against hookworm. The cure rates for both parasites were moderate with thiabendazole and poor with levamisole.

Albendazole↗

Measurement of antibody response to keyhole limpet haemocyanin was not adequate for early diagnosis of schistosomiasis in a group of Dutch visitors to Mali.

The detection of antibodies against keyhole limpet haemocyanin (KLH) (extracted from Megathura crenulata) has been described as a reliable tool for serological diagnosis of acute, but not chronic, schistosomiasis. We evaluated the immunoglobulin (Ig) G and IgM anti-KLH enzyme-linked immunosorbent assay (ELISA) for the serological diagnosis of light schistosome infections and to follow response after treatment, using sera from a group of Dutch travellers returning from Mali with acute schistosomiasis. Before chemotherapy, the sensitivities of the anti-KLH IgM and IgG ELISAs were 74% and 63%, respectively. In contrast, a sensitivity of 100% was found with an immunofluorescence assay for determination of IgM antibodies against gut-associated glycoconjugates. There was no significant difference in the anti-KLH response before, and one year after, therapy. These results indicate that, for travellers from non-endemic areas like The Netherlands with generally light schistosome infections, detection of antibody response against KLH is not a useful tool for serodiagnosis of acute schistosomiasis.

Acute Disease↗

Clinical epidemiology and classification of human oesophagostomiasis.

The intestinal helminth Oesophagostomum bifurcum is highly and focally endemic in northern Ghana and Togo, and its juveniles produce a nodular inflammatory response as they develop in the intestinal wall. This pathology can produce clinical symptoms. We report on 156 cases of oesophagostomiasis presenting in 1996-98 to Nalerigu hospital in northern Ghana. The disease accounted for 0.2% of the out-patient department new presentations (about 1 patient per week), and 1% (16) of the major acute surgical cases. Children aged 5-9 years were most commonly affected. Multinodular disease (13% of the cases) results from hundreds of pea-sized nodules within the colon wall and other intra-abdominal structures, and presents with general abdominal pain, persistent diarrhoea and weight loss. Dapaong tumour (87%) presents as an abdominal inflammatory mass often associated with fever. The 3-6-cm tumour is painful, well-delineated, smooth, spherical, 'wooden', periumbilical, and adhered to the abdominal wall. Cases most commonly presented during the late rains and early dry season. Diagnosis by ultrasound has reduced the need for exploratory surgery, and the ability to sonographically evaluate conservative treatment with albendazole has curtailed management by colectomy or incision and drainage.

Abdominal Pain↗

Natural progression of Oesophagostomum bifurcum pathology and infection in a rural community of northern Ghana.

An estimated 250,000 people in northern Ghana and Togo are infected with the intestinal helminth parasite Oesophagostomum bifurcum, as detected by stool cultures. Clinical disease caused by O. bifurcum is responsible for about 50 cases per year at the region's central hospital, and presents as painful abdominal masses: inflammatory colonic nodules containing live juvenile stages of the helminth. In individuals living in villages highly endemic with O. bifurcum infection, colonic pathology visible by ultrasound is also highly prevalent. These nodules also contain O. bifurcum juvenile worms but are apparently asymptomatic. Thus, O. bifurcum infection and asymptomatic colonic pathology are highly prevalent within this area, but clinical disease is relatively uncommon. The natural evolution and regression of the colonic pathology in an endemic community in northern Ghana and its distribution within the population is described. Of the 299 individuals in the study group, 28% had colonic pathology at recruitment in the late-rainy season, which decreased with a half-life of 3-4 months during the dry season. Of those negative at recruitment, 28% developed nodules during the year, the majority appearing at the end of the subsequent rainy season. Children tended to have a higher prevalence and intensity of ultrasound-visible pathology compared to adults. Almost half (49%) of the study group had colonic nodules at least once during the year, and 2% of these individuals presented with clinical disease to the local hospital during the mid-rainy season.

Adolescent↗

Serum circulating egg antigen levels in two areas endemic for Schistosoma mansoni.

A monoclonal antibody-based enzyme-linked immunosorbent assay detecting Schistosoma mansoni circulating soluble egg antigen (CSEA) was applied in epidemiological studies. The serum CSEA levels were determined for 2 populations with a high prevalence (> 95%) and high intensity of infection as determined by faecal egg counts. In one population (Maniema, Zaire) transmission had been occurring for several decades, while in the other population (Ndombo, Senegal) transmission had started only recently. CSEA could be detected in 88% and 70% of the serum samples from Maniema and Ndombo, respectively. The sensitivity of the CSEA assay increased with rising egg count. The age-related CSEA profiles of the Maniema population followed a pattern similar to that of egg counts and of the adult worm antigen CAA (circulating anodic antigen). However, the recently infected Ndombo population showed a clearly different profile: while the CSEA prevalence reached a peak in children and adolescents, the mean CSEA levels did not vary significantly in the different age groups. CSEA levels were significantly lower in Ndombo than in Maniema. As egg antigens in serum are thought to be in part, or even primarily, derived from eggs in the tissues, these findings indicate a relatively smaller tissue egg load in Ndombo than in Maniema.

Adolescent↗