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Biomedical subjects

V I Mathan

Publications and source records attributed to V I Mathan.

120 records · Page 7Linked to original sources

Jejunal surface pH measurements in tropical sprue.

The mucosal surface pH of jejunal biopsy samples incubated in vitro in Krebs-phosphate buffer was measured. Biopsies from 7 healthy individuals or tropical sprue subjects in complete remission had a mean surface pH of 5.8 +/- 0.09, similar to values for normal Caucasian subjects living in the UK. The mean surface pH of biopsies from 20 sprue patients, 6.0 +/- 0.08, was significantly higher (P less than 0.05) than that of the control subjects. Sprue patients could be sub-divided into those with 2 or more abnormal results in 3 intestinal function tests, and those with one or no abnormal test. The 9 low scorers showed a mean surface pH of 5.75 +/- 0.06 resembling the control mean, whereas the 11 high scorers had a higher (P less than 0.01) mean surface pH of 6.17 +/- 0.08. Mucosal surface pH correlated directly with 3 d mean faecal fat excretion and inversely with xylose and vitamin B12 absorption values but not with the nutritional indicators serum albumen, folate or blood haemoglobin levels. As in coeliac disease, mucosal surface pH in the jejunum is elevated above normal in tropical sprue and may reflect the extent to which normal ion transport processes are affected.

Feces↗

Diagnosis of Strongyloides and hookworm infections: comparison of faecal and duodenal fluid microscopy.

Faecal microscopical diagnosis of Strongyloides and hookworm infections is insensitive. We have therefore compared duodenal fluid and faecal microscopy for detection of these parasites in a group of 292 patients being investigated for gastrointestinal symptoms who were examined by both techniques. Thirty-three of these patients (8%) were infected with Strongyloides stercoralis and 88 (30%) had hookworm infections. Microscopical examination of up to 3 faecal specimens detected only 33% and 65% of patients with Strongyloides and hookworm infections, respectively. Microscopical examination of a single specimen of duodenal fluid was more sensitive for detection of strongyloidiasis, identifying 76% of patients; the parasite was found exclusively in duodenal fluid (and not in faeces) in 67% of patients. For hookworm, the diagnostic sensitivity was similar with both techniques but duodenal fluid microscopy detected some patients (35%) who had not been identified by faecal microscopy. This study confirms previous work indicating the insensitivity of faecal microscopy in these infections and emphasizes the need to consider routine examination of duodenal fluid to exclude chronic strongyloidiasis. This may have particular relevance for south-east Asian war veterans and immunocompromised patients.

Ancylostomatoidea↗

The relative merits of faecal and duodenal juice microscopy in the diagnosis of giardiasis.

We compared the diagnostic accuracy of microscopical examination of multiple faecal specimens with duodenal juice examination in the diagnosis of giardiasis. Of 292 patients who had stool microscopy and duodenal aspirate, Giardia were identified in either stools or duodenal fluid from 73 patients (25%). Giardiasis was diagnosed in 62 (73%) with the first faecal specimen, but examination of 3 specimens increased the diagnostic yield to 85%. Giardia, however, were found in only 32 of 73 duodenal aspirates examined (44%). This finding is contrary to the widely held belief that duodenal fluid examination is superior to stool microscopy for the diagnosis of giardiasis. The 2 approaches are complementary, however, since Giardia was found in duodenal fluid, only, from 15% of patients.

Body Fluids↗

Food-based solutions are a viable alternative to glucose-electrolyte solutions for oral hydration in acute diarrhoea--studies in a rat model of secretory diarrhoea.

A survey of acute diarrhoea and its treatment, in 3 groups of villages in south India, revealed that use of the World Health Organization oral rehydration solution (WHO-ORS) was poor or virtually non-existent and that several liquid foods were given to children during acute diarrhoea. The effects of the most commonly used, boiled and cooled supernatants of these liquid foods [rice (Oryza sativa)-water, ragi (Eleusine coracana)-water, arrowroot (Maranta arundinacea)-water], and tender coconut-water, and of the bicarbonate- and citrate-WHO-ORS on intestinal water transport were evaluated using a rat model of secretory diarrhoea. All solutions either decreased cholera toxin-induced net water secretion (arrowroot-water) or reversed it to net absorption. Ragi-water produced maximum net water absorption, significantly greater than the WHO oral rehydration solutions. WHO-ORS utilization is poor in some developing countries, and locally used food-based solutions could be used for maintaining hydration or correcting the dehydration due to acute diarrhoea once their effectiveness has been proved by clinical trials.

Acute Disease↗

Intestinal manifestations of invasive diarrheas and their diagnosis.

Data from studies of 916 children with diarrhea, including 122 from whom shigellae were isolated, and data on patients affected in an epidemic due to Shigella dysenteriae type I were analyzed to determine whether a diagnostic clinical profile of shigellosis could be identified. Blood and/or mucus in stool, increased frequency of stool, abdominal pain, rectal tenesmus, and fever were noted more frequently in patients with shigellosis. The diagnostic confirmation of shigellosis depends on the isolation of the organism, but in the clinical situation early initiation of appropriate antibiotic therapy can be based on clinical judgment that utilizes local perceptions regarding dysentery.

Child, Preschool↗

Morphology of rectal mucosa of patients with shigellosis.

Biopsy specimens of rectal mucosa from 46 consecutive patients with dysentery, from whom shigellae were isolated, were examined. On examination it appeared that the specialized epithelial cells overlying lymphoid follicles were the first to be damaged, and subsequently a vascular lesion led to detachment of epithelial cells. The vascular lesion was widespread in the lamina propria mucosae. Extensive ulceration was associated with invasion of epithelial cells by the organism. There was marked depletion of mucus and an increase in mitotic activity in the crypts. Abscesses of the crypts were rare. The only difference between patients from whom the Shiga bacillus was isolated and patients from whom other shigellae were isolated was a higher prevalence of epithelial cell detachment and luminal exudate. In patients who had been ill for greater than 1 week, cell damage of the crypts was associated with cell-mediated cytolysis, a release of cytotoxic substances from eosinophils and mast cells, and relative vascular insufficiency, all of which may contribute to persistence of dysentery.

Dysentery, Bacillary↗

Prevalence of Helicobacter pylori in southern Indian controls and patients with gastroduodenal disease.

The spiral organism Helicobacter pylori has been causally implicated in the genesis of various gastroduodenal diseases. Since these diseases are common in southern India, this study was undertaken to determine the prevalence of H. pylori in the gastric mucosa of asymptomatic adults and patients with various gastroduodenal diseases. H. pylori was detected in the gastric mucosa of 25 of 30 (83.3%) normal volunteers. Prevalence rates in the disease groups were also high, and included 38 of 41 patients with duodenal ulcer (92.6%), 13/16 with gastric ulcer (81.3%), and 85/119 subjects (71.4%) with non-ulcer dyspepsia. Light microscopic examination of the gastric mucosa provided the best method of detecting H. pylori. H. pylori colonization was significantly associated with histological abnormalities, mainly chronic atrophic gastritis (147) and superficial gastritis (11), while only three of 161 H. pylori positive patients had histologically normal antral mucosa. Ultrastructural examination revealed changes in the apical complex of the gastric mucosal cells in response to bacterial adhesion, with mucus depletion and cellular damage. Bacteria were also noted disrupting the tight junctions and entering the intercellular spaces. The high prevalence of H. pylori infection may explain the high incidence of gastritis, duodenal ulceration and gastric carcinoma in this population. However, in this population, the prevalence of infection in asymptomatic individuals was nearly as high as that in duodenal ulcer, underlining the need for further study to identify the differences in host response or bacterial pathogenicity that lead to the development of ulcer in only some individuals.

Adolescent↗

A combined TDDA-PVC pH and reference electrode for use in the upper small intestine.

Incorporation of a ligand into polyvinylchloride allows the production of ion selective electrodes that are soft-bodied and disposable. With features make them especially suitable for clinical, particularly gastroenterological, investigations. We report here on the construction of a combined reference and pH electrode suitable for use at jejunal biopsy. With this type of pH electrode, the pH of the mucosal surface of the jejunum in UK and in Indian subjects, without evidence of upper gastrointestinal disease, was about pH 6.0. This was almost identical to previous values measured using a separate reference electrode. Both the polymer electrode and a suitable data logger can be conveniently produced in the laboratory and compare favourably with commercially available systems, provided the range of pH likely to be encountered is within the operating range of the incorporated ligand.

Amines↗

Eosinophilic gastroenteritis--an Indian experience.

Eosinophilic gastroenteritis is an uncommon disorder with varied presentation. Records of 7 patients (6 men) with eosinophilic gastroenteritis, presenting to a large referral hospital over a 10-year period, were analyzed. The patients were young adults (mean age 32 years) with short duration (median 2 months) of illness. Symptoms included abdominal pain and vomiting (100%), weight loss (57%), diarrhea (43%) and abdominal distension (43%). Peripheral eosinophilia was present in all the patients. The diagnosis was made at duodenal (2 patients) or cecal (1) biopsy or surgical full-thickness jejunal biopsy (4). Three patients had predominantly mucosal disease (Klein type I), whereas two patients each had predominantly muscular (type II) and submucosal (type III) disease. Surgical resection was curative in one patient with type II disease. The other six responded to prednisolone, with complete resolution in one patient.

Adult↗