The passage of Trichobilharzia szidati schistosomula through the vertebrate lungs was examined in natural and abnormal hosts--birds (ducks Anas platyrhynchos f. domestica) and mammals (mice Mus musculus Bagg albino/c [BALB/c]), respectively. Using the methods of classical histology, the migratory route of worms was characterized, and the impact of migration on host tissues and the host cell reactions were evaluated. Living schistosomula were recorded in the lungs of ducks 2-10 days post infection (p.i.) and in the lungs of mice 2-4 days p.i. In ducks, the schistosomula migrated from the blood vessels through the blood capillaries to the lung tissue; then, they entered free air space of the lungs. The infection resulted in inflammatory reaction with nodules composed of infiltrated lymphocytes, heterophils, eosinophils and macrophages. These structures were formed around the blood vessels and in the gas-exchange tissues of the parabronchial walls and, consequently, in the walls of secondary bronchi. An extensive inflammation of secondary bronchi and parabronchi was observed. In the lungs of mice, the parasites were localized extravascularly in the alveolar walls. No migratory pattern similar to that in the lungs of ducks was recorded. No specific inflammatory reaction occurred. However, alveolar wall congestion, edema and lymphocyte infiltrates appeared and, therefore, pathogenicity of T. szidati was also confirmed in the murine host.

; and the Cytological Diaconesses Group BACKGROUND: The performance of cytologic screening and its correlation with histology and polymerase chain reaction (PCR) detection of human papillomavirus (HPV) DNA have not been evaluated in populations with a low prevalence of anal intraepithelial neoplasia (AIN). The objective of the current study was to analyze the significance of abnormal smears relative to the histology and PCR detection of HPV DNA. METHODS: A cytologic smear and a viral sample were taken in 300 consecutive patients undergoing surgery (Milligan-Morgan hemorrhoidectomy and/or fissurectomy) who gave their informed consent. RESULTS: The cytologic smear was normal in 216 of 290 patients (74.5%). Four high-grade and 19 low-grade intraepithelial neoplastic lesions were identified. In 5 patients, high-grade lesions could not be excluded, 30 lesions were of undetermined significance, and there were 16 cellular modifications with a non-neoplastic appearance. The PCR test for HPV was positive in 18.7% of patients, and a high-risk genotype was identified in 63.6% of positive samples. Histologic examination of the surgical samples was normal in 92.3% of patients. The 23 AIN samples were distributed as follows: 13 grade 1 AIN (AIN1), 6 AIN2, and 4 AIN3. The sensitivity of cytologic smears and PCR for detecting AIN was 56% and 60.8%, respectively, and specificity was 77% and 84.5%, respectively. Combining the 2 tests increased sensitivity to 78% but decreased specificity to 68%. CONCLUSIONS: Compared with a large surgical sample, anal cytologic Papanicolaou smears and HPV PCR exhibited sensitivity and specificity that varied, depending on the risk of HPV infection and AIN. Positive HPV DNA screening increased with AIN grade, and high-risk HPV testing was particularly helpful. INTRODUCTIONThe cervical Papanicolaou (Pap) smear is known as a good cancer screening test. Its widespread use has enabled a significant reduction in cervical cancer morbidity and mortality. 1 Anal and cervical cancers share similarities, including intraepithelial neoplastic lesions known to progress to cancer and a causative association with human papillomavirus (HPV). 2 The usefulness of anal cytology for detecting anal intraepithelial neoplasia (AIN) has been demonstrated in populations at high risk of cancer of the anal canal, ie, men who have sex with men (MSM) and individuals infected with the human immunodeficiency virus (HIV). 3 Anal Pap smears and high-resolution anoscopy (HRA), thus, have been recommended as screening tests for high-risk populations. 4 However, for populations in which the prevalence of AIN is lower, little is known about the performance of cytologic screening and its correlation with histology and HPV DNA detection. Published results have varied concerning the sensitivity and specificity of anal cytology, 5 and, when available, histologic samples have issued from blinded or forceps biopsy with or without HRA guidance. 6,7 Because AIN often is multifocal, small biopsy specimens, particularly forceps biopsies, may ...

This work confirms that the frequency of low-grade squamous intraepithelial lesion is raised in HIV-seropositive males and also where there is a history of condyloma, which corroborates the necessity for regular monitoring and screening of these patients at risk. This study also suggests that the use of tobacco is associated with anal cytologic abnormalities.