[Laboratory survey on the incidence of Pneumocystis jirovecii - obviously a peculiar fungus, but also a rare pathogen?]. / Laborerhebung zur Häufigkeit von Pneumocystis jirovecii - Zwar ein besonderer Pilz, aber auch ein seltener Erreger?

Pneumocystsis jirovecii is a peculiar fungus for a variety of reasons. This opportunistic pathogen multiplies in humans only under certain conditions; a defect in the T-cell defense system creates a predisposition to this infection. In 2010 a data survey (IFT as well as PCR) from a few laboratories in Germany revealed 412 positive individuals. Even if only a few patients test positive for the colonization stage of this pathogen, the sheer number of individuals testing positive for other stages of infection indicate that the incidence of pneumocystosis in immunocompromised patients in Germany is underestimated.

Evaluation of an immunofluorescence assay for specific detection of immunoglobulin G antibodies directed against Helicobacter pylori, and antigenic cross-reactivity between H. pylori and Campylobacter jejuni.

An immunofluorescence assay (IFA) for the detection of immunoglobulin G antibodies directed against Helicobacter pylori was evaluated by comparing 20 serum specimens from patients with a positive urease test on biopsy material and 20 serum specimens from patients with a negative test and with defined clinical symptoms. The resulting anti-H. pylori titers were classified as follows: negative, less than or equal to 64; borderline, 128; and positive, greater than or equal to 256. By using these criteria, the IFA was subsequently tested, using 100 serum specimens from patients with gastric complaints. Overall, the titers were 71% positive, 10% borderline, and 19% negative. Depending on the patients' biopsy urease test results, the sensitivity and specificity of the assay were calculated to be 96%. Furthermore, these sera were classified into three subgroups on the basis of clinical manifestations: gastritis with 74% positive and 10% borderline titers, duodenal ulcer with 84% positive and 4% borderline titers, and gastric ulcer with 52% positive and 16% borderline titers. A serologic follow-up study was carried out with three patients with gastric ulcers who had been treated with colloidal bismuth subcitrate for 4 weeks and erythromycin for the final 2 weeks. The results indicate that a significant decrease in titer could be expected within 9 to 12 months after successful therapy, as determined by repeated negative CLO tests. Absorption experiments demonstrated that possible cross-reactivity between H. pylori and C. jejuni did not influence serodiagnosis.