[Chagas disease in the Netherlands: an estimate of the number of patients]. / De ziekte van Chagas in Nederland: een schatting van het aantal patiënten.

A total of 8-10 million persons are infected worldwide with Trypanosoma cruzi, the causative parasite of Chagas disease, most of whom are inhabitants of Latin America. Due to the increased migration of peoples, Chagas disease has been on the uprise outside Latin America, including in Europe. The course of Chagas, also called American trypanosomiasis, runs in 2 phases: an acute phase lasting approximately 2 months, and a chronic phase in which symptoms may appear years after infection. Without treatment, the patient will remain infected for life. The acute phase is usually asymptomatic; in the chronic phase of American trypanosomiasis, severe gastro-intestinal and cardiac abnormalities may develop, finally with fatal course. In the Netherlands, the number of immigrants who would serologically test positive for American trypanosomiasis is estimated to be between 726 and 2929. Healthcare providers in the Netherlands may encounter patients who have Chagas disease more and more frequently. The screening of pregnant women and blood donors at risk for American trypanosomiasis should be considered.

The potential of molecular diagnosis of cutaneous ectopic schistosomiasis.

A 28-year-old woman presented with extensive erythematous lesions on her back after visiting Malawi. Skin biopsies showed ova, which could belong to Schistosoma spp. Sequencing of the Schistosoma 28S rRNA gene, extracted and amplified from paraffin biopsies, identified DNA of Schistosoma haematobium. Cutaneous ectopic schistosomiasis can present with extensive lesions and should be considered in the differential diagnosis of skin lesions in returning travelers. Microscopy and serology are the classical methods to obtain a diagnosis. Alternatively, molecular methods can be a valuable new tool for diagnosis and species determination.

Specific cross-reactivity in sera from cystic echinococcosis patients in an enzyme-linked immunoelectrotransfer blot for cysticercosis diagnostics.

A commercially available enzyme-linked immunoelectrotransfer blot originally intended for diagnosis of cysticercosis was evaluated for echinococcosis diagnosis, because a characteristic band pattern--different from the specific cysticercosis pattern--was observed in sera from patients with echinococcosis. This band pattern was observed in 29 (78%) of 37 parasitologically proven cystic echinococcosis patients. Specificity of these bands was 100% for echinococcosis, when tested with 75 control sera.

Reliable serodiagnosis of imported cystic echinococcosis with a commercial indirect hemagglutination assay.

A commercially available indirect hemagglutination assay (IHA) (Echinococcosis Fumouze; Laboratoires Fumouze, Levallois-Perret, France) was evaluated using sera from 52 patients with proven cystic echinococcosis. The specificity was assessed using 247 sera from patients with various parasitic, bacterial, viral, and fungal infectious diseases; sera containing autoimmune antibodies; and sera from healthy blood donors. With a cutoff value for a positive result of 320 (as recommended by the manufacturer), the sensitivity and specificity were 88% and 98.4%; with a cutoff of 160, the sensitivity and specificity were 94% and 95.1%, respectively. The IHA is rapid, easy to perform, and is a very sensitive serodiagnostic test for cystic echinococcosis.

Use of rapid dipstick and latex agglutination tests and enzyme-linked immunosorbent assay for serodiagnosis of amebic liver abscess, amebic Colitis, and Entamoeba histolytica Cyst Passage.

A homemade enzyme-linked immunosorbent assay (ELISA) and a dipstick assay (Dipstick) for the detection of anti-Entamoeba histolytica antibodies in serum were developed and evaluated together with a commercially available latex agglutination test (LAT; Laboratoires Fumouze) for their use in serodiagnosis of amebiasis. The sensitivity of these assays was evaluated with sera from 27 patients with radiologically proven, cellulose acetate precipitation (CAP) test-positive amebic liver abscess, 7 patients with parasitologically and PCR-proven amebic colitis, and 11 patients with parasitologically and PCR-proven E. histolytica cyst passage. The sensitivities of the ELISA, Dipstick, and LAT were all 93.3% (42/45). With a combination of Dipstick and LAT, all abscess and colitis patients had at least one positive result. The specificity was assessed with 238 sera from patients with various parasitic, bacterial, viral, and fungal infectious diseases, sera containing autoimmune antibodies, and sera from healthy blood donors. The specificities of the ELISA, Dipstick, and LAT were 97.1%, 98.1%, and 99.5%, respectively. Of 61 sera from patients with PCR-proven E. dispar infection, 60 (98.4%) were negative in both Dipstick and LAT and 59 (96.7%) were negative in ELISA. Our data suggest that all three assays are sensitive serological tests. The rapid LAT and Dipstick provide fast results and can easily be applied in routine laboratories in order to facilitate the diagnosis of amebiasis.

Direct amplification and genotyping of Dientamoeba fragilis from human stool specimens.

Dientamoeba fragilis is a globally occurring parasite that has been recognized as a causative agent of gastrointestinal symptoms. A single-round PCR was developed to detect D. fragilis DNA directly from human stool samples. The genetic diversity of D. fragilis from 93 patients and 6 asymptomatic carriers was examined by PCR followed by restriction fragment length polymorphism and sequencing of part of the small-subunit rRNA gene. The data show that D. fragilis sequences can be studied directly from fecal specimens despite the absence of a cyst stage and without the need for prior culturing. In addition, the results suggest strongly that D. fragilis shows remarkably little variation in its small-subunit rRNA gene.

Value of diagnostic techniques for cutaneous leishmaniasis.

BACKGROUND: Traditional diagnostic tests, ie, smear, culture, and histopathology of a skin biopsy specimen, are not always conclusive in patients with a clinical diagnosis of cutaneous leishmaniasis (CL). OBJECTIVE: Our purpose was to find out if a polymerase chain reaction (PCR) specific for Leishmania organisms might be more sensitive than the traditional diagnostic techniques, thereby decreasing the number of false-negative diagnoses. METHODS: In a prospective study, smear, culture, and histopathology of skin biopsy specimens from 46 patients with a possible diagnosis of CL were compared with PCR specific for Leishmania. In addition, the Montenegro test as a measure of cellular immunity against the Leishmania parasite was performed. Proven CL was defined as a case in which at least 1 of the 3 traditional tests showed the presence of Leishmania parasites. RESULTS: Of our 46 patients, 22 had leishmaniasis. Of the traditional tests, culture was the most sensitive but there were no statistically significant differences between the sensitivities of the various tests. PCR results were positive in all cases of proven leishmaniasis. Moreover, 3 patients with the clinical diagnosis of CL and negative findings on traditional tests had positive PCR results. Only 1 patient with a strong clinical suggestion of CL and positive Montenegro test results had negative PCR findings; this patient also had negative smear, culture, and histopathology results. CONCLUSION: PCR appears to be the most sensitive single diagnostic test for CL.