Search PubMed⌕ Search

Biomedical subjects

R D Montgomery

Publications and source records attributed to R D Montgomery.

At least 37 records · Page 2Linked to original sources

Levamisole toxicosis in a dog.

A single oral dose of levamisole hydrochloride given at the rate of 12 mg/kg was believed responsible for bradycardia, tachypnea, hypothermia, cerebrocortical depression, and diarrhea in a dog. Supportive treatment and symptomatic treatment for the bradycardia were required for 4 days. In addition to these previously reported abnormalities associated with levamisole toxicosis, cerebrocortical depression and multiple foci of irritation were characterized by electroencephalography.

Animals↗

Causes of malabsorption in the elderly.

The pathogenesis of malabsorption has been studied in 70 patients who presented over the age of 65 years and who were referred to a special investigative unit. Often more than one cause was apparent. Fourteen patients had pancreatic insufficiency, most of whom had no history of pain, alcoholism or gallstones. Twenty-three patients had the postgastrectomy syndrome or small-bowel diverticulosis or both. There were eight coeliacs aged 65-72 years at diagnosis. Fifteen patients had an anatomically normal small bowel; eight of these were over 80 years old, and 10 had vitamin B12 deficiency of whom five had confirmed pernicious anaemia. Enterobacterial overgrowth was a feature of all diagnostic groups except pancreatic and coeliac disease. Vitamin B12 deficiency may be an effect of malabsorption, but can also be a cause through impairment of enterocyte function. The association of pernicious anaemia and B12 deficiency with otherwise unexplained malabsorption and bacterial overgrowth suggests that gastric atrophy is a major causal factor in this syndrome, combined in some cases with a 'vicious circle' of B12 malabsorption and deficiency.

Aged↗

Small bowel contamination and vitamin B12 deficiency in the elderly.

Bacterial contamination of the small bowel in the elderly can occur without any anatomical defect, but the importance and pathogenesis of this phenomenon are debatable. We describe two such patients, both with profound vitamin B12 deficiency. Clinical recovery took place without specific treatment of the bacterial overgrowth. In one patient with pernicious anemia, malabsorption of xylose and fat was corrected after vitamin B12 therapy. In the other gastric acidity was normal, but unsuspected mesenteric ischemia led to gangrene of the bowel. In old age there may be more than one explanation for vitamin B12 deficiency and for bacterial overgrowth. Vitamin B12 deficiency within the intestinal cells may be one common factor leading to malabsorption.

Aged↗

Post-infective malabsorption in the temperate zone.

A series of 37 adults normally resident in Britain have been investigated for persistent bowel symptoms following acute enteritis. 26 had intestinal malabsorption, of whom 12 had been travelling in the Mediterranean area, whereas 10 developed their illness at home. Mild jejunal mucosal abnormalities were found in cases with and without malabsorption, and the intraepithelial lymphocyte count correlated more closely with the degree of malabsorption than did the histological grading. Over 80% of severe cases were folate deficient. Enterobacteria were cultured from the jejunal fluid in 30% of cases. Our observations confirm that post-infective malabsorption occurs sporadically in adults in the temperate zone and is occasionally severe. The condition involves small bowel contamination with enterobacteria, and it differs from acute tropical sprue only in its greater tendency to spontaneous recovery.

Adolescent↗

Changing clinical pattern of gastric ulcer: are anti-inflammatory drugs involved?

The changing pattern of gastric ulcer (GU) has been studied in a series of 528 cases presenting in one hospital department during the past 20 years. The male:female ratio has declined and is now equal, and age-adjusted figures show that this applies to all age groups. There was a significant decline in mid-gastric ulcers in men. There was a 4-fold increased incidence of haemorrhage in proximal as opposed to antral ulcers and a 7-fold excess of haemorrhage in older women as opposed to younger women. GU in elderly women taking non-aspirin non-steroidal anti-inflammatory drugs (NANSADs) showed an increased tendency to bleeding, accounting for half of all haemorrhages in women over 70 years. However, on statistical analysis NANSAD-associated ulcers showed no other distinguishing features, and the use of NANSADs did not contribute significantly to the changing sex ratio. There is still no satisfactory evidence that these drugs play a causal role in chronic GU.

Adult↗

Intestinal absorption in Saudi Arabia: an evaluation of the one hour blood xylose test.

The screening value of the one-hour blood xylose test, corrected for body surface area, was prospectively studied in Saudi Arabian adults and children under investigation for suspected intestinal malabsorption. Sensitivity of discrimination between patients with and without upper small bowel disease was 91%, compared to 85% for the five-hour urine xylose test. Primary small bowel disorder was rare. In a three-year review, no cases of adult coeliac disease or tropical sprue were found. The most common causes of malabsorption were intestinal tuberculosis, abdominal lymphoma and immunoproliferative small intestinal disease. Despite its acceptability as an index of proximal small bowel function, the blood xylose test alone is an inadequate screening test for any of these conditions.

Adolescent↗

Factors affecting the serum iron-binding capacity in the elderly.

The relationship of the serum iron-binding capacity (IBC) to the serum proteins and other haematological parameters was studied in 96 elderly subjects. With two exceptions, IBC levels above the normal range were confined to cases of anaemia with transferrin saturation levels of less than 12%. In 13 cases the IBC was below normal, and in 9 it was normal in the presence of iron deficiency; in these groups the IBC correlated with serum albumin, and there was a clinical explanation for protein depletion. In cases with normal serum albumin and normal transferrin saturation, there was no decline in IBC with age. The best serological index of iron status was the transferrin saturation, which was less than 12% in significant iron deficiency. Malabsorption of inorganic iron was demonstrated in 11 out of 30 iron-deficient patients, 4 of whom had reduced IBC, but there was no relationship between iron absorption and the IBC.

Age Factors↗

Toxic megacolon in ulcerative colitis: a continuing challenge.

The incidence, predisposing factors, management and outcome of toxic megacolon (TM) has been reviewed in 65 cases of severe ulcerative colitis (UC) and compared in 2 successive 6-year periods before and after January, 1973. Nineteen episodes of TM occurred in 18 patients. Despite a conscious aim towards earlier surgery in recent years this was not achieved, and despite more intensive medical therapy the incidence of TM was unchanged. Emergency operative mortality in UC fell from 36% to 21% but the mortality of TM remained at 30%. The chief cause of death was colonic perforation. Mortality was associated with increased age, longer pre-operative hospital stay and lower levels of serum albumin. These findings reemphasize the need for earlier surgery if TM is to be prevented, but such a policy must result in some unnecessary emergency colectomies.

Adult↗

Significance of serum complement levels in patients with gastrointestinal disease.

Levels of the serum complement components, C3 and C4, in patients with Crohn's disease, ulcerative colitis, and miscellaneous gastrointestinal disorders were compared with those of normal blood donors. Significant increases of both components were found in all three patient groups, the highest being in patients with Crohn's disease. Generally, levels of C3 and C4 were lower in patients with inactive rather than active Crohn's disease and ulcerative colitis. These results provide some evidence in support of an immunological basis for inflammatory bowel disease. However, in view of the frequent elevation of C3 and C4 in other gastrointestinal diseases, it is equally possible that the complement components are behaving as acute phase proteins.

Blood Donors↗

Evaluation of xylose absorption as measured in blood and urine: a one-hour blood xylose screening test in malabsorption.

The assessment of D-xylose absorption by measurement of urinary excretion is subject to several sources of error. An investigation has been made into the use of the blood levels obtained after a 5-g dose as an assessment of malabsorption. We have shown that optimal discrimination between normal and impaired xylose absorption is achieved by measuring blood xylose levels 1 hr after oral administration and then correcting the results to a constant body surface area. The reference range was 0.65 to 1.33 mmoles per liter for values corrected to 1.73m2. In a prospective study of the value of this modification in investigating malabsorption, the incidence of false-negatives and false-positives was found to be 4.8 and 2.2%, respectively. The test is of particular value in the elderly because surface area corrected 1-hr blood xylose levels are independent of age, eliminating the expected and observed declines in renal function and urinary xylose excretion in this age group.

False Negative Reactions↗

The ageing gut: a study of intestinal absorption in relation to nutrition in the elderly.

This study was designed to assess the functional efficiency of the ageing small intestine and the possible role of malabsorption in old people with nutritional deficiencies. Fifty subjects aged 65 to 92 years were studied, of whom 33 presented with anaemia, chronic diarrhoea or bone pains, and 17 were apparently healthy 'controls' with no relevant symptoms. Tests of intestinal function included blood xylose and iron absorption curves, a double isotope Schilling test, faecal fat, urinary indican and small bowel radiology, with duodenal aspiration and jejunal biopsy in some cases. On the basis either of steatorrhoea or at least two other abnormal parameters of absorption, there were 15 cases of malabsorption. Thirteen of these had symptoms but two were 'controls'. Four of these had duodenal diverticulosis, two had the post-gastrectomy syndrome, and one had calcific pancreatitis. Malabsorption in the remaining eight cases was not fully explained. The age range of this last group was 72--86 years; one of them had a contaminated small bowel and two showed some evidence of pancreatic insufficiency. Malabsorption emerged as a significant cause of low levels of serum iron, haemoglobin and calcium. The blood xylose test is a useful screening procedure for intestinal malabsorption in old age, but full evaluation calls for investigation of pancreatic function.

Aged↗

Chronic inflammatory bowel disease in Asian immigrants.

Chronic inflammatory bowel disease occurs sporadically among the immigrant Asian population in Britain, but information about the incidence and clinical features is lacking. We therefore report our experience of 13 patients seen in a gastrointestinal unit in Birmingham over the past 12 years.

Adolescent↗