Parasitological diagnosis of schistosomiasis mansoni: fecal examination and rectal biopsy

Even with all progress in the search of sensitive and methods for the immunological diagnosis of schistosomiasis, the microscopic detection of eggs of the parasite in the stool still remains the most widely used tool for the actual diagnosis of active infection. Among the coproscopic methods, Kato's technic modified by Katz et al (Kato/Katz) has the advantages of higher sensitivity, the possibility of egg quantification, its low operational cost and its feasibility in areas with minimal infra-structure. The oorgram of the rectal mucosa is valuable in initial clinical trials of schistosomicides, when it is needed to observe egg morphology in tissue. It could be an alternative method for individual diagnosis, being more sensitive than a single stool exam in low intensity infection. However, the increased sensitivity of a higher number of fecal exams makes that invasiveprocedure unnecessary. In the assessment of cure of schistosomiasis, Kato/Katz method (three fecal samples in one, three and six months after treatment) and the rectal biopsy four months after treatment, are equally reliable

Changes in glycosaminoglycan synthesis and in heparan sulfate deposition in human colorectal adenocarcinomas.

Biosynthesis of glycosaminoglycans (GAGs) was studied in morphologically normal colonic mucosa, in peritumoral and tumoral areas, and in colorectal polyps of tumor-bearing patients. After GAG purification, overall biosynthesis was determined: the general trend was a decrease in GAG production in neoplastic colon, lowest GAG synthesis being observed in Dukes' stage C tumors. Separation by ion-exchange chromatography of various GAG species and further characterization revealed the presence of hyaluronic acid (HA) and heparan sulfate (HS) molecules in all specimens studied. Chondroitin-4 sulfate (CS4) was occasionally found in tumor samples. The relative proportion of HA and HS was modified in tumor tissue: i.e. increased HA and decreased HS were observed. Differences in DEAE-chromatographic behavior were obvious in pathological samples as compared to controls, the hydrodynamic form of HA and the charge density of HS being decreased. The latter could be attributed to undersulfatation of HS molecules. Immunocytochemical detection of HS proteoglycan molecules revealed regular and bright labelling at epithelial-stromal interface in control samples. In pathological samples, staining was patchy and discontinuous, showing large areas of basement membrane interruption.

Serum and rectal mucosal magnesium status in acute and chronic diarrhoea.

Serum and rectal mucosal magnesium content was estimated in children (6-18 months old) with acute diarrhoea (Group I: n = 50), chronic diarrhoea (Group II: n = 25), extra-intestinal infections (Group III: n = 15) and healthy controls (Group IV: n = 20). The sex and nutritional status of the different groups were comparable. The mean serum magnesium levels in acute and chronic diarrhoea were comparable to healthy and infected controls. The tissue magnesium content of infants with chronic diarrhoea was significantly (P less than 0.001) lower than other groups. Repeat estimation at discharge in 38 patients (25 in Group I, 13 in Group II) revealed a significant reduction in serum levels in both groups (P less than 0.05 and P less than 0.01, respectively) and in tissue levels in acute diarrhoea (P less than 0.05). A total of 23 infants (16 in Group I) were evaluated 2-3 weeks after discharge. There was an increase in tissue magnesium content at recovery in acute (P less than 0.02) and chronic (P greater than 0.05) diarrhoea groups. It is concluded that infants with chronic, but not acute diarrhoea, are magnesium depleted at presentation; with the continuation of diarrhoea there is a progressive depletion of magnesium; and there is a tendency to regain the magnesium status during the convalescent period.

Restoration of colorectal continuity reverses atrophy in human rectal mucosa.

Cell kinetic activity and adaptive response of rectal mucosa from patients with Hartmann's procedure were studied before and after restoration of colorectal continuity. Patients without colostomy and with normal rectal mucosa were used as controls. Autoradiography of in vitro labeled mucosal samples with [3H]thymidine was used. The proliferative activity in the rectal crypts was estimated by measuring labeling and mitotic indices, total DNA of isolated crypts, and total crypt cell numbers. One hundred forty days after creating a proximal end colostomy, labeling index (P less than 0.05), mitotic index (P less than 0.01), DNA content per crypt (P less than 0.05), and number of cells per crypt (P less than 0.05) decreased significantly compared to control values. Restoration of colorectal continuity resulted in a significant increase of the labeling index (P less than 0.05), the mitotic index (P less than 0.01), the DNA content per crypt (P less than 0.05), and the cell number per crypt (P less than 0.05). There were no significant differences between the postclosure values and the controls. These data indicated that excluding the human rectal mucosa from fecal stream determined a mucosal atrophy that could be reversed by restoration of colorectal continuity.

Bombesin-like immunoreactive material in the gut, and the effect of bombesin on the stomach circulatory system of an elasmobranch fish, Squalus acanthias.

The distribution, nature and amount of bombesin-like immunoreactivity (IR) in the gastrointestinal canal and its afferent vessels was investigated in the spiny dogfish (Squalus acanthias) together with the in vitro effect of synthetic bombesin on perfusion flow through the vascularly perfused dogfish stomach. Nerve fibres showing bombesin-like IR frequently occurred in the walls of the anterior mesenteric and coeliac arteries and the intrinsic vessels of the gut. Chromatographic studies revealed that multiple peaks of bombesin-like IR material were present in extracts of the spiny dogfish gastrointestinal vessels. Bombesin-like IR was also present in muscle and mucosal layers of the gut with higher levels in muscle compared with mucosa, and higher levels in the stomach than in the intestine and the rectum. Exogenous bombesin increased the flow through the vasculary perfused spiny dogfish stomach in a dose-dependent manner. Studies with tetrodotoxin and atropine showed that bombesin probably exerts its effect directly on the vascular musculature. It is concluded from this study that bombesin-like material is present in nerves innervating the gut circulatory system of the spiny dogfish. Bombesin may affect the blood-flow to the gastrointestinal canal, possibly via a direct effect on vascular smooth muscle.

The distribution of galanin message-associated peptide-like immunoreactivity in the pig.

Using a radioimmunoassay (RIA) developed to the N-terminal part of the predicted sequence of porcine galanin message-associated peptide (GMAP), we have confirmed the existence of GMAP-like immunoreactivity (-LI) in normal porcine tissues. GMAP-LI was found to parallel the distribution of galanin-immunoreactivity (-IR), although consistently the concentrations detected were, on a molar ratio, significantly less than those measured for galanin throughout the gastrointestinal tract, brain, spinal cord, adrenal and pituitary gland. As cleavage of the prohormone would be expected to produce galanin and GMAP on an equimolar basis, it is possible that the endogenous, intact GMAP peptide does not fully cross-react with the antibody raised to the N-terminal GMAP sequence. Gel chromatography of tissue extracts revealed a single molecular form of galanin-IR in the gut and four distinct molecular forms in the adrenal gland. GMAP-LI eluted as a single immunoreactive component in the gut, and in the adrenal gland there were two major molecular forms, one of which was apparently also detected by the galanin assay, and a small amount of N-terminal fragment. This molecular heterogeneity seems likely to be a result of the various possible prohormone cleavage products and/or posttranslational processing modifications. Further analysis of the galanin gene products needs to be undertaken in order to confirm this.

Serum and rectal mucosal zinc levels in acute and chronic diarrhea.

Serum and rectal mucosal zinc content was estimated in children (6-18 months old) with acute diarrhea (Group I: n = 50), chronic diarrhea (Group II: n = 25), extraintestinal infections (Group III: n = 15) and apparently healthy controls (Group IV: n = 20). The sex and nutritional status of various groups was comparable. The mean serum and tissue zinc levels in acute (p less than 0.001) and chronic (p less than 0.05 for serum; p less than 0.001 for tissue) diarrhea groups were significantly lower than healthy and infected controls. Group II had significantly lower (p less than 0.001) serum and rectal zinc content in comparison to Group I. There was a significant negative correlation between serum zinc and diarrheal duration (r = 0.5676; p less than 0.001). Repeat estimation at discharge in 38 patients (25 in Group I, 13 in Group II) revealed a significant reduction in both tissue and serum zinc and only tissue zinc in acute and chronic diarrhea, respectively. A total of 23 patients (16 in Group I, and 7 in Group II) were evaluated 2 weeks after discharge. After discharge, at recovery there was no alteration in serum zinc, but tissue zinc was marginally higher (p greater than 0.05). It is concluded that zinc depletion occurs in diarrhea, more so in the chronic state; with the continuation of diarrhea, depletion progresses; and there is a tendency for repletion during convalescence.

DNA content of rectal scrapings from individuals at low and high risk for the development of colorectal cancer. A feasibility study.

Scrapings of superficial rectal mucosa were collected from 31 patients with colorectal carcinoma, 66 patients with sporadic adenoma, and 53 control subjects with no personal or family history of colorectal cancer. The DNA ploidy level and proliferative patterns of each specimen were analyzed by flow cytometry (FCM). A GMS index, calculated as the ratio of G2 + M:S, was found to be significantly lower in control subjects than in any of the high-risk groups studied. Aneuploidy was more prevalent in rectal scrapings from cancer patients and adenoma patients than in those from control subjects. Aneuploid cell populations were detected in apparently normal rectal scrapings from two control subjects. Some high-risk individuals (i.e., cancer patients and patients with adenomas and a family history of cancer) exhibited higher proportions of tetraploid (designated G2/M) cells and a higher G2/M:S phase ratio than control subjects. The results accumulated thus far show that the rectal scraping procedure is safe and easy to perform. Our limited findings give hope that the DNA content analysis of cells obtained by rectal scraping may eventually prove useful in mass screening for colorectal cancer risk. However, definitive evaluation will require further refinement and elaboration of analytic technique and testing on more patients at various levels of predetermined risk.

Hereditary amyloidosis: evidence against early amyloid deposition.

Twelve members of the Indiana hereditary amyloidosis type II kindred were tested for the presence of amyloid deposits. All were young adults (age 26-37), with no evidence of disease and with 1 affected parent. Six were found to be carriers of the variant gene, by DNA testing and/or reduced serum retinol-binding protein levels. Nevertheless, no amyloid could be found in any skin, rectal, or carpal tunnel biopsy specimens. Our results suggest that hereditary amyloidosis type II is a true late-onset disease, in which accumulation of amyloid does not start until late in life--perhaps only a short time before symptoms appear.

Prognostic significance of epithelioid granulomas found in rectosigmoid biopsies at the initial presentation of pediatric Crohn's disease.

The prognostic significance of epithelioid granulomas in Crohn's disease (CD) remains controversial. We have determined the prognostic significance of epithelioid granulomas noted in endoscopic rectosigmoid biopsies obtained from untreated pediatric patients at initial presentation of CD. Data collected from 19 subjects with rectosigmoid granulomas and inflammation (Group 1) were compared to those obtained from another 37 subjects (Group 2) with CD of the rectosigmoid, but in whom no granulomas were present. Both groups had similar ages at disease onset [Group 1: 11.6 +/- 3.6; Group 2: 10.4 +/- 4.0 years (X +/- SD)]. At diagnosis, Group 1 had more extensive CD (small bowel and colon involvement, with Group 1 74% versus Group 2 30%; isolated rectosigmoid involvement, with Group 1 11% versus Group 2 35%; p less than 0.01). Perianal disease was also more common in Group 1 (58% versus 27% Group 2; p less than 0.05). However, CD activity scores and clinical laboratory findings were comparable. Duration of follow-up was identical (5.6 +/- 3.3 years) for both groups. By the end of the period of follow-up, 43% of Group 2 had developed small bowel involvement, but Group 1 continued to have more extensive CD (p less than 0.05). Perianal fistulae and abscesses and anal stenosis were more frequent in Group 1. Throughout this period, the need for oral and parenteral corticosteroids, 6-mercaptopurine, and nutritional support modalities were similar in the two groups. Although the number of subjects requiring hospitalization and the number of hospitalizations per patient were similar in both groups, Group 1 had more surgery (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Subcutaneous fat biopsy in the diagnosis of amyloidosis secondary to chronic arthritis.

Subcutaneous fat biopsy was investigated for its sensitivity in giving a diagnosis in 44 consecutive patients with rheumatoid arthritis or ankylosing spondylitis suspected of systemic amyloidosis. In 26 of these patients amyloidosis could be demonstrated by fat or rectal biopsy or biopsies from organs suspected of amyloid deposition. Fourteen of the 26 (54%) fat biopsy specimens of the patients with amyloidosis were positive after staining with Congo red and 22 (85%) of the rectal biopsy specimens were positive. All 12 kidney biopsy specimens and 4 biopsy specimens from other organs of these 26 patients were positive for amyloidosis. In 2 patients with a negative rectal biopsy specimen, fat biopsy would have obviated the need for a more invasive biopsy. All patients experienced fat biopsy as less demanding compared to other biopsy procedures. These results imply that in patients with chronic arthritis subcutaneous fat biopsy is a useful screening procedure. In this patient group fat biopsy is less sensitive for the diagnosis of amyloidosis compared to rectal biopsy.

Serum and rectal mucosal copper status in acute and chronic diarrhea.

Serum and rectal mucosal copper content was estimated in children (6-18 months old) with acute diarrhea (group I: n = 50), chronic diarrhea (group II: n = 25), extraintestinal infections (group III: n = 15), and apparently healthy controls (group IV: n = 20). The sex and nutritional status of various groups was comparable. The mean serum copper levels in acute diarrhea and infected control groups were comparable, but significantly (p less than 0.001) greater in comparison to chronic diarrhea and healthy control groups. The tissue copper in group II was significantly (p less than 0.001) lower than other groups, which were comparable. There was a significant negative correlation between serum copper and diarrheal duration (r = -0.615; p less than 0.001). Repeat estimation at discharge in 38 patients (25 in group I and 13 in group II) revealed a significant (p less than 0.05) reduction in the serum and tissue copper content during this period. Among the 23 infants (16 in group I and 7 in group II) evaluated 2-3 weeks after discharge, there was an increase in copper values of tissue alone (p less than 0.05) in group I and both serum and tissue (p less than 0.05) in group II. It is concluded that elevation of serum copper in acute diarrhea is a nonspecific response to infection; infants with chronic but not acute diarrhea are copper depleted at presentation; and with the continuation of diarrhea, there is a progressive depletion of copper.

Intramural distribution of regulatory peptides in the sigmoid-recto-anal region of the human gut.

The distribution of regulatory peptides was studied in the separated mucosa, submucosa and muscularis externa taken at 10 sampling sites encompassing the whole human sigmoid colon (five sites), rectum (two sites), and anal canal (three sites). Consistently high concentrations of VIP were measured in the muscle layer at most sites (proximal sigmoid: 286 (16) pmol/g, upper rectum: 269 (17), a moderate decrease being found in the distal smooth sphincter (151 (30) pmol/g). Values are expressed as mean (SE). Conversely, substance P concentrations showed an obvious decline in the recto-anal muscle (mid sigmoid: 19 (2.0) pmol/g, distal rectum: 7.1 (1.3), upper anal canal: 1.6 (0.6)). Somatostatin was mainly present in the sigmoid mucosa and submucosa (37 (9.3) and 15 (3.5) pmol/g, respectively) and showed low, but consistent concentrations in the muscle (mid sigmoid: 2.2 (0.7) pmol/g, upper anal canal: 1.5 (0.8]. Starting in the distal sigmoid colon, a distinct peak of tissue NPY was revealed, which was most striking in the muscle (of mid sigmoid: 16 (3.9) pmol/g, upper rectum: 47 (7.8), anal sphincter: 58 (14)). Peptide YY was confined to the mucosa and showed an earlier peak (upper sigmoid: 709 (186) pmol/g, mid-distal sigmoid: 1965 (484)). A clear differential distribution of regulatory peptides was thus shown in the region studied. A possible role is suggested for NPY and VIP containing nerves in the effector control of the human internal anal sphincter.

Fecapentaenes and their precursors throughout the bowel--results of an autopsy study.

The fecapentaenes are potent mutagens found in the stool of some humans and pigs. These compounds are produced by Bacteroides species in the gut from an uncharacterized family of precursor compounds, and have been postulated to pose a risk of human colorectal cancer. To better understand fecapentaene production in vivo, and to determine if excreted levels measured in epidemiologic studies are representative of the entire colon, fecapentaenes were assayed from multiple sites in the bowel in an autopsy study of 16 humans and 2 pigs. An indirect measurement of fecapentaene precursors was also made. Colonic concentrations of fecapentaenes and precursors varied widely between individuals, but were consistent for each individual throughout the colon. In addition, the measurements of rectal contents, assumed to approximate values in excreted stool, were equivalent to measurements from the colon.

Lectin expression in neoplastic and non-neoplastic lesions of the rectum.

The expression of six lectins (Arachis hypogaea, B. simplicifolia I, concanavalin A, Dolichus biflorus, Triticum vulgaris, Lotus tetragonolobus) was studied in 24 adenocarcinomas, 24 adenomas, 20 metaplastic polyps, 17 specimens of mucosal prolapse (solitary ulcer syndrome) and 10 of normal mucosa, all taken from the rectum. Qualitative, quantitative and distributive differences in lectin expression were observed between adenocarcinoma and normal mucosa. These cancer-associated glycoprotein alterations were also observed, though to a lesser extent, in benign neoplastic and non-neoplastic lesions of the rectum. It appears therefore that the glycoprotein modifications associated with malignant transformation are not specific indicators of malignancy. It is suggested that the common denominator is a disturbance in the activities of enzymes, particularly the glycosyl-transferases and glycosidases, involved in the biosynthesis of glycoprotein. This disturbance can occur in situations where cells are less differentiated either through developmental immaturity, rapid cellular division or neoplastic de-differentiation. These changes are therefore more likely to reflect the state of differentiation rather than the malignant nature of the cells. It is shown that the greater the deviation of the lesion from normal the greater the glycoprotein alterations. The potential usefulness of lectin expressions as predictive indicators of biological behaviour of adenocarcinomas of the large bowel needs further studies.

Histochemistry of mucins of pig intestinal secretory epithelial cells before and after weaning.

Two histochemical staining techniques, Alcian blue/PAS and high-iron-diamine/Alcian blue, which differentiated neutral from sulphated and sialylated acid mucins were applied to sections of duodenum, ileum, caecum, colon and rectum from pigs aged one day, 3 weeks and 10 weeks. In each age group, sulphated-acid mucins predominated at all sites, particularly in the large intestine. In both the small and the large intestine, non-sulphated mucins occurred mainly at the bases of the crypts. Neutral mucins occurred in a few goblet cells in crypts and villi, either alone or together with acid mucins; neutral mucins increased away from the bases of the crypts. No changes were noted in the caecum, colon or rectum of pigs one, two, 5 or 13 days after weaning onto a diet containing soya protein. In the small intestine, there was a transient increase in the numbers of goblet cells in the crypts and villi, a relative increase in sulphated and a decrease in non-sulphated acid mucins and a change in the distribution of sulphated mucins in the crypts. No change in proportions of neutral and acid mucins was detected.