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Query: UMLS:C0001175 (AIDS)
 120,706 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The significance of the human immunodeficiency virus (HIV) in the small intestinal lamina propria in patients with the acquired immune deficiency syndrome or conditions related to that syndrome who have chronic diarrhea and malabsorption is unclear. To investigate this issue, upper endoscopy (after a 12- to 16-hour fast) with duodenal biopsy and aspirate was performed in 20 HIV-infected seropositive homosexual men referred for diarrhea of more than 8 weeks duration (Group 2) and in 9 HIV-infected homosexual men referred for dysphagia or dyspepsia with no symptoms of malabsorption (Group 1). All biopsy specimens were examined by light microscopy and immunochemical staining with monoclonal antibody against HIV glycoprotein gp41. Electron microscopy was performed in 18 patients in Group 2 and in all patients in Group 1. Immunogold electron microscopy was used as a confirmatory test for identified HIV particles. In addition, D-xylose absorption was measured in all patients after a 25-g dose of D-xylose with measurement of serum D-xylose concentration 1 hour after the dose and measurement of 5-hour urinary D-xylose excretion. Mean serum D-xylose was 35.4 +/- 4.5 mg/dL in Group 1 and 15.8 +/- 2.3 mg/dL in Group 2 (P less than 0.001), whereas mean urine D-xylose was 5.5 +/- 0.6 g in Group 1 and 2.0 +/- 0.4 g in Group 2 (P less than 0.001). Immunoperoxidase for gp41 was positive in 5 (56%) patients in Group 1 and in 12 (60%) patients in Group 2. Lamina propria HIV viral particles were identified by electron microscopy in both patient groups. Viral particles were seen within and adjacent to the cytoplasm of mononuclear cells and were not present in enterocytes or neuroendocrine cells. There were no significant differences in serum or urine D-xylose tests between patients with and without lamina propria HIV. In addition, lipid accumulation in intercellular spaces near the basolateral membrane of adjacent enterocytes was seen in 33% of patients with chronic diarrhea. These findings suggest that lamina propria HIV is not a direct cause of enteropathy in HIV-infected patients and that lymphatic obstruction may be one pathophysiologic mechanism producing this malabsorptive state.
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PMID:Histopathologic findings of duodenal biopsy specimens in HIV-infected patients with and without diarrhea and malabsorption. 141 28

D-Xylose absorption was studied in 12 patients with acquired immunodeficiency syndrome (AIDS) or advanced AIDS-related complex who had had diarrhea for more than 8 weeks, averaged an 11% (range, 3% to 21%) body weight loss during the previous 6 months, and had had negative stool examinations for enteric pathogens. Patients were evaluated by duodenal aspiration and biopsy and received both 25 gm oral and 10 gm intravenous doses of D-xylose. Kinetic analysis of D-xylose absorption was characterized by an absorption rate constant (ka) and a rate constant (ko) reflecting nonabsorptive loss. Extent of D-xylose absorption averaged 18.4% +/- 9.3% (+/- SD) in the 12 patients (normal greater than 60%). Percentage of weight loss during the previous 6 months was negatively correlated with ka (r = -0.69; p = 0.018) in the 11 patients in whom this parameter was reduced but was not correlated with either ko or extent of D-xylose absorption. In these patients with human immunodeficiency virus enteropathy, ka was reduced out of proportion to the minor histologic changes present in the duodenal biopsy specimens.
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PMID:Kinetics of D-xylose absorption in patients with human immunodeficiency virus enteropathy. 206 Feb 52

Malnutrition in patients with acquired immune deficiency syndrome (AIDS) is common and multifactorial. The possible causes of malnutrition were evaluated by performing studies of energy balance in five clinically stable outpatients with AIDS, six seronegative homosexual control subjects, and five seronegative heterosexual control subjects. The AIDS group was significantly depleted of body cell mass compared with the control subjects but the values did not change significantly over 6 wk. Food intake was normal in the AIDS group whereas intestinal absorptions of the pentose sugar xylose and of the triglyceride triolein were both significantly diminished. The AIDS patients were hypometabolic as compared with the control subjects and with predictions of metabolic rate based on the Harris-Benedict equation. We conclude that short-term energy balance can be maintained in clinically stable patients with AIDS. Hypometabolism is an appropriate metabolic response to the combination of body-cell-mass depletion and nutrient malabsorption.
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PMID:Preservation of short-term energy balance in clinically stable patients with AIDS. 229 30

This paper will describe a case series of 35 AIDS patients with infection of the gastrointestinal (GI) tract with Mycobacterium avium-intracellulare (MAIC). Thirty-five homosexual men with a mean age of 35 yr and a mean duration of AIDS of 7.7 months prior to the diagnosis of MAIC were investigated to determine the extent of MAIC infection. The investigations included upper endoscopy, sigmoidoscopy, liver biopsy, bone marrow aspiration and biopsy, stool and blood cultures for MAIC, and D-xylose absorption tests. Tissue biopsy material was examined by light microscopy with the Ziehl-Neelsen stain. The duodenum was most commonly involved (30/34 men), with 65% positive on special stains and 76% positive on culture of biopsy tissue. Unusual fine white nodules, believed to be characteristic for duodenal MAIC infection, were observed in 12 men. Esophageal (two men), liver (two men), and rectal involvement (seven men) were found. In nine of 18 men (50%), the D-xylose test was abnormal. In 28 of 33 men (85%), blood cultures grew MAIC. Similarly, in 25 of 28 men (89%), bone marrow biopsies grew MAIC, and in 18 of 21 men (86%) stool samples grew MAIC. We conclude that GI tract infection with MAIC in AIDS patients is frequently associated with systemic infection with the agent. Duodenal involvement is common, and may be accompanied by a characteristic gross lesion, that of fine white nodules on the mucosa. Malabsorption, as determined by the D-xylose test, is not a universal finding, as has been reported previously.
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PMID:Atypical mycobacterial infection of the gastrointestinal tract in AIDS patients. 259 53

Diarrhea and weight loss may accompany the acquired immunodeficiency syndrome. We studied 30 patients with the syndrome, 20 of whom had diarrhea and weight loss and 10 of whom did not. Patients with identifiable enteric infections or small intestinal Kaposi's sarcoma were excluded. Malabsorption was common in the patients with diarrhea and weight loss, as shown by abnormal D-xylose and 14C-glycerol-tripalmitin absorption tests. In these patients, duodenal biopsy specimens showed a histiocytic infiltrate containing numerous acid-fast organisms in 5 and a mild-moderate chronic inflammation in 13. In asymptomatic patients, duodenal biopsy specimens were normal in 6 and showed chronic inflammation in 4. These results suggest that malabsorption is common in patients with the acquired immunodeficiency syndrome with chronic diarrhea and may contribute to their weight loss.
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PMID:Malabsorption and mucosal abnormalities of the small intestine in the acquired immunodeficiency syndrome. 398 13

Chronic diarrhoea is frequent in acquired immune deficiency syndrome (AIDS) but has been poorly investigated so far. We report four patients with AIDS in whom diarrhoea and malabsorption were outstanding features, and who underwent extensive digestive investigations. Diarrhoea was a presenting symptom in all subjects and was of secretory type in three of them. D-xylose and vitamin B12 were malabsorbed in all cases; steatorrhea was found in the two patients who could ingest significant amounts of fat. Faecal alpha 1-antitrypsin clearance was increased in all subjects. Search for digestive pathogens showed unusual protozoans in all patients: in case 1, optical and electron microscopy revealed the presence in the cytoplasm of villous enterocytes of Microsporidia protozoans still unreported in AIDS. Stool and jejunal fluid examination showed Isospora belli in case 2 and Cryptosporidium in cases 3 and 4. On histological and ultrastructural study the former was localised in the cytoplasm of a few enterocytes and the latter was scattered throughout the villus and crypt brush border. Otherwise small intestinal histology only showed minor non-specific changes and the enterocytes were ultrastructurally normal. In patient 3 the slow marker intestinal perfusion technique showed a profuse fluid secretion in the duodenum and proximal jejunum. All patients needed prolonged total parenteral nutrition. Cryptosporidium and Microsporidia could not be eradicated despite multiple drug trials. Isospora belli was transiently cured by pyrimethamine-sulphadiazine. Only patient 2 is presently at home, and patients 1, 3, and 4 died after two, six, and nine months of total parenteral nutrition, respectively.
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PMID:Diarrhoea and malabsorption in acquired immune deficiency syndrome: a study of four cases with special emphasis on opportunistic protozoan infestations. 403 92

Patients with acquired immunodeficiency syndrome (AIDS) frequently have diarrhea and weight loss. We prospectively examined the upper and lower gastrointestinal tracts in 22 AIDS patients, although severe medical problems often precluded full evaluation. Ninety-six percent (21 of 22) lost weight, and 55% (12 of 22) had diarrhea. The mean (+/- SD) weight loss was 34 +/- 19 lb. Steatorrhea was found in 4 of 14 patients, and D-xylose tests were abnormal in 8 of 14 patients. Mean serum albumin was 3.3 +/- 0.8 g/dl. A significantly diminished plasma selenium level, which can influence immune function, was noted in these AIDS patients. Gastrointestinal infections were identified in 45% of patients. Although diarrhea and malabsorption were more common in the infected group, weight loss and albumin were similar in those with and without demonstrated infections. Flexible sigmoidoscopy showed that of 15 patients, there were two with Kaposi's sarcoma, 10 normals, and three with nonspecific endoscopic changes of colitis. Infection was documented in all patients with colitis. Panendoscopy of the upper gastrointestinal tract was positive for AIDS-related pathology in five of 10 patients, including two with Kaposi's sarcoma, one with Candida esophagitis, one with herpetic esophagitis, and one with gastroduodenitis (biopsy positive for cryptosporidia); five patients had a normal-appearing tract. Small bowel or colonic biopsies frequently showed nonspecific inflammatory changes, although pathogens were identified in six patients (27% of all biopsies). We conclude that a wide variety of gastrointestinal pathology, which includes infectious agents, neoplasms, and inflammatory changes, may occur in AIDS patients. Therefore, AIDS patients, particularly those with diarrhea or weight loss, deserve an intensive evaluation for remediable lesions of their gastrointestinal tracts.
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PMID:Gastrointestinal manifestations of the acquired immunodeficiency syndrome: a review of 22 cases. 404 Nov 33

Ten patients were identified at Jackson Memorial hospital/University of Miami Hospitals and Clinics with enteric coccidial infection due to Cryptosporidium spp. or Isospora belli. All had the acquired immunodeficiency syndrome as manifested by Kaposi's sarcoma or multiple opportunistic infections, or both. They presented with profuse diarrhea associated with weakness, anorexia, and weight loss. Routine examinations of stools for eggs and parasites as performed by the hospital laboratory were negative in all patients. Sugar flotation and modified acid fast techniques were used in the Tropical Disease Laboratory to identify oocysts of Cryptosporidium spp. in stools of seven patients. Malabsorption, characterized by a low 5-hour D-xylose and positive fecal fat, was observed in 6/6 of these patients. In three other patients Isospora belli oocysts were identified in stool specimens or via a duodenal string test. Spiramycin was the only drug found to be effective in treating patients with cryptosporidiosis. Patients with Isospora belli responded to a prolonged course of trimethoprim-sulfamethoxazole.
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PMID:Enteric coccidiosis among patients with the acquired immunodeficiency syndrome. 633 48

Clinical observation suggests that the natural history of intestinal cryptosporidiosis in patients with acquired immunodeficiency syndrome varies greatly. The relation between clinical, small-bowel functional, and nutritional status and the intestinal distribution of the organism was studied in 41 patients who had acquired immunodeficiency syndrome and cryptosporidiosis and who had undergone both proximal small-bowel and colonic biopsies. Two patterns of enteric cryptosporidiosis were identified: severe clinical disease with malabsorption in patients with cryptosporidia in proximal small-bowel biopsy specimens (61% of cases) and less severe clinical disease in patients with cryptosporidia only in the colon or stool (39% of cases). Patients with cryptosporidia in proximal small-bowel biopsy specimens had small-bowel crypt hyperplastic villous atrophy, lamina propria inflammatory infiltrates, poorer D-xylose absorption, greater weight loss, and shorter survival and more often needed intravenous hydration or hyperalimentation. Patients with cryptosporidia in the small-bowel villi only had less severe disease than those with cryptosporidia in the small-bowel crypts. In conclusion, the anatomic distribution of intestinal cryptosporidia in patients with acquired immunodeficiency syndrome varies, and this variation may explain differences in clinical course. Cryptosporidial infection of the proximal small bowel correlates with mucosal injury, malabsorption, dehydration, weight loss, and shortened survival.
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PMID:Variation in the enteric distribution of cryptosporidia in acquired immunodeficiency syndrome. 794 97

To characterize the absorptive defect of AIDS enteropathy, we have used a D-xylose kinetic model of proximal absorption and correlated these findings with Schilling's test for cobalamin absorption, measurements of distal intestinal function. In addition, we compared findings between duodenal and jejunal biopsy and aspirations to determine whether additional information can be obtained by sampling the more distal site. Twelve consecutive patients with AIDS who had 3 to 14 loose bowel movements per day and two stool study results negative for pathogens, were admitted for study. D-xylose testing with oral and intravenous doses was used to determine the rate constants for D-xylose absorption, Ka, and the rate constant for nonabsorptive loss, Ko. Duodenal and distal duodenal-jejunal endoscopic aspirations and biopsies were also performed. Minimal histologic abnormalities were seen in either the proximal or distal biopsy sites. There were no significant differences in mucosal blunting, abnormalities of the enterocytes, lamina propria infiltrate, or presence of microorganisms between duodenal and distal duodenal-jejunal sites. Seventy-five percent had no identifiable pathogens. Ten of 12 patients had diminished Ka, elevated Ko, or both. Two patients had a normal Ka and Ko. Eight of 10 had an abnormal Schilling's test result. Percentage weight loss correlated negatively with Ka (r = 0.75; p = 0.013) and with Schilling's test results (r = 0.65; p = 0.043. Ka correlated positively with Schilling's test results (r = 0.82; p = 0.004).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Small intestinal HIV-associated enteropathy: evidence for panintestinal enterocyte dysfunction. 796 23


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