Giardia intestinalis and Fructose Malabsorption: A Frequent Association

Nowadays, scientific studies are emerging on the possible etiological role of intestinal parasites in functional digestive disorders. Our study was carried out with healthy individuals (control group; n = 82) and symptomatic patients with lactose or fructose malabsorption, including positive (malabsorbers; n = 213) and negative (absorbers; n = 56) breath test, being analyzed for the presence of intestinal parasites. A high parasitic prevalence was observed in malabsorbers (41.8%), exclusively due to single-cell eukaryotes but not helminths. Giardia intestinalis was the predominant parasite in cases of abnormal absorption (26.5%), significantly associated with fructose malabsorption and doubling the probability of developing this pathology. Within controls, Blastocystis sp. (13.4%) was almost the only parasite, being the second among patients (12.6%), and Cryptosporidium parvum, the last species of clinical relevance, was detected exclusively in two malabsorbers (0.9%). The consumption of ecological food and professions with direct contact with humans arose as risk factors of parasitism. A diagnosis of carbohydrate malabsorption in adulthood is the starting point, making the search for the primary cause necessary. Accurate parasitological diagnosis should be considered another tool in the clinical routine for patients with recurrent symptoms, since their condition may be reversible with adequate therapeutic intervention.

HTLV infection and strongyloidal hyperinfection syndrome

Strongyloides stercoralis can affect humans in the form of asymptomatic infections, Strongyloidal hyperinfection syndrome and disseminated Strongyloidiasis depending on the immune response of the host. We report a case of strongyloidial hyperinfection syndrome that subsequently tested positive for HTLV infection.

Parasites in patients with malabsorption syndrome: a clinical study in children and adults

BACKGROUND

Intestinal parasites not only cause diarrheal diseases but also significant malabsorption. Literature on the role of parasites, such as intestinal coccidia and microsporidia in malabsorption syndrome is limited.

METHODS

Three consecutive stool samples from 50 adult and 50 children patients with malabsorption syndrome and an equal number of healthy controls without diarrhea were examined for intestinal coccidia, microsporidia and other intestinal parasites by wet mount, Kinyoun's modified acid-fast staining and chromotrope 2R staining.

RESULTS

Celiac disease was the commonest cause of malabsorption syndrome in both adults (52%) and children (74%). Forty (80%) and 41 (82%) adults and children, respectively, with malabsorption syndrome were infected with parasites. These results were significantly higher in comparison to those from the healthy adults and children controls (22% and 16%), respectively (P < 0.001). Of them, 48% and 46% of the adults and children, respectively, with malabsorption had pathogenic parasitic infections. The pathogenic parasites detected in adults were Giardia lamblia 12 (24%), E. histolytica / dispar 5 (10%), Ancylostoma duodenale 4 (8%), H. nana 2 (4%) and Cyclospora cayetanensis 1 (2%). The pathogenic parasites detected in children with malabsorption syndrome were Giardia lamblia 8 (16%), Cryptosporidium 7 (14%), E. histolytica / dispar 3 (6%), Ancylostoma duodenale 3 (6%), Isospora belli 1 (2%), and H. nana 1 (2%). None of the stool samples from healthy controls were positive for Cryptosporidium spp., Cyclospora and Isospora belli. All the patients infected with intestinal coccidia were HIV sero-negative.

CONCLUSION

Celiac disease is the most common cause of malabsorption syndrome in both adults and children. These people harbor significantly more pathogenic parasites and are more frequently colonized with harmless commensals as compared to healthy controls. Intestinal coccidia are associated with malabsorption syndrome, particularly in malnourished children.

Chronic diarrhea and malabsorption caused by Leishmania donovani

Chronic diarrhea and malabsorption are uncommon in immunocompetent patients with visceral leishmaniasis. We report two immunocompetent patients with visceral leishmaniasis where the predominant presentation was chronic diarrhea. One of them had clinically overt malabsorption and duodenal mucosa was loaded with Leishmania donovani bodies. The other patient had diffuse colonic aphthous and discrete ulcerations and Leishmania donovani bodies were seen in the crush smears of the colonic mucosa. With amphotericin B, there was reversal of malabsorption and healing of colonic ulcers.

Effect of chronic Giardia lamblia infection on epithelial transport and barrier function in human duodenum

BACKGROUND

Giardia lamblia causes infection of the small intestine, which leads to malabsorption and chronic diarrhoea.

AIM

To characterise the inherent pathomechanisms of G lamblia infection.

METHODS

Duodenal biopsy specimens from 13 patients with chronic giardiasis and from controls were obtained endoscopically. Short-circuit current (I(SC)) and mannitol fluxes were measured in miniaturised Ussing chambers. Epithelial and subepithelial resistances were determined by impedance spectroscopy. Mucosal morphometry was performed and tight junction proteins were characterised by immunoblotting. Apoptotic ratio was determined by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labelling staining.

RESULTS

In giardiasis, mucosal surface area per unit serosa area was decreased to 75% (3%) of control, as a result of which epithelial resistance should increase. Instead, epithelial resistance of giardiasis biopsy specimens was decreased (19 (2) vs 25 (2) Omega cm(2); p<0.05) whereas mannitol flux was not significantly altered (140 (27) vs 105 (16) nmol/h/cm(2)). As structural correlate, reduced claudin 1 expression and increased epithelial apoptosis were detected. Furthermore, basal I(SC) increased from 191 (20) in control to 261 (12) microA/h/cm(2) in giardiasis. The bumetanide-sensitive portion of I(SC) in giardiasis was also increased (51 (5) vs 20 (9) microA/h/cm(2) in control; p<0.05). Finally, phlorizin-sensitive Na(+)-glucose symport was reduced in patients with giardiasis (121 (9) vs 83 (14) microA/h/cm(2)).

CONCLUSIONS

G lamblia infection causes epithelial barrier dysfunction owing to down regulation of the tight junction protein claudin 1 and increased epithelial apoptoses. Na(+)-dependent d-glucose absorption is impaired and active electrogenic anion secretion is activated. Thus, the mechanisms of diarrhoea in human chronic giardiasis comprise leak flux, malabsorptive and secretory components.

Mechanisms of epithelial dysfunction in giardiasis

A better understanding of the pathophysiological processes of Giardia may lead to understanding the diseases it causes and to identifying new therapeutic agents

An unusual cause of malabsorption in an immunocompetent host

Gastrointestinal tract infestation with Strongyloides stercoralis is common in the tropical and subtropical areas of the world. In an immunocompetent person, disease is generally asymptomatic. However, it has the potential to cause serious life threatening disease in an immunocompromised patient. We report a 55 years old immunocompetent person who presented with malabsorption secondary to strongyloides stercoralis infestation. Unusual infestations like strongyloides should also be considered while investigating malabsorption.

Tropical malabsorption

Tropical malabsorption remains an important clinical problem for both the indigenous population of tropical countries and for short-term visitors and longer-term residents from the industrialized world. In young children, persistent diarrhea and malabsorption can result in severe retardation of growth and development. The most common cause is an intestinal infection notably the small intestinal protozoa including Giardia intestinalis, Cryptosporidium parvum, Isospora belli, Cyclospora cayetanensis, and the microsporidia. Tropical sprue still remains an important diagnostic option but is less common than it was 20 to 30 years ago. It is important to attempt to make a specific microbiological diagnosis as this will influence the choice of antibiotic. However, if laboratory facilities are not available, it is possible to offer empirical therapy although this may involve a trial of more than one antibiotic.

Poor intestinal permeability in mildly stunted Nepali children: associations with weaning practices and Giardia lamblia infection

Studies in the Gambia, using the lactulose-mannitol dual-sugar intestinal permeability test (lactulose:mannitol ratio) as a non-invasive way of investigating mucosal damage, have shown that food malabsorption is significantly associated with early growth retardation. In this cross-sectional study, 210 poor urban Nepali children, 0-60 months old, were recruited and measured for height or length and weight, 167 were examined for intestinal permeability and 173 for parasite infection. Weaning and morbidity data were collected from 172 caretakers. Children were mildly stunted (mean height-for-age z-score -1.45) and underweight (mean weight-for-age z-score -1.62). The lactulose:mannitol ratio (0.26) was poorer than that of UK children (0.12), but similar to that found in Bengali children of the same age (0.24). Two stages of weaning, the onset supplementary feeding (6 months) and the cessation of breast-feeding (23 months), were shown to have differential impact. In children currently breast-feeding, the duration of supplementation was negatively related to lactose (P<0.001) and lactose:lactulose values (P<0.0001), indicating lactose maldigestion. In children who had ceased breast-feeding, a longer period of lactation was associated with poorer intestinal permeability (P=0.031), and poorer height-for-age (P=0.024), which was an unexpected result. No significant relationships were found between intestinal permeability and growth, or with morbidity and helminth infection, except in children with Giardia lamblia who had worse lactulose:mannitol ratios than those without (0.43 v. 0.25 respectively, P=0.014). It is likely that insults to the gut (e.g. Giardia) and challenges to the immune system (weaning) have a different impact in early and late infancy.

Strongyloidiasis associated with nephrotic syndrome

We report a nephrotic syndrome patient with eosinophilia who developed ileus, epigastralgia and malabsorption due to strongyloidiasis which became symptomatic by steroid therapy. The patient was then treated with thiabendazole and recovered. A percutaneous renal biopsy revealed minimal change nephrotic syndrome. This renal injury may be brought on by severe infection of Strongyloides stercoralis. It is important to rule out strongyloidiasis prior to corticosteroid therapy to patients from eosinophilia endemic areas.

Prevalence of intestinal microsporidiosis in HIV-infected individuals referred for gastroenterological evaluation

OBJECTIVES

The reported prevalence of enteric pathogens, especially microsporidiosis, in HIV infection varies greatly. In this study, the prevalence rates for microsporidiosis and other enteric pathogens in HIV-infected individuals referred for gastrointestinal symptoms were compared.

METHODS

This prospective study included 250 HIV-infected individuals (179 with AIDS) who were referred for GI evaluation (diarrhea in 194). The prevalence rates of symptomatic intestinal disease due to microsporidiosis and other intestinal pathogens were determined by clinical evaluation, and their epidemiological, clinical, and immunological characteristics were compared.

RESULTS

Enteric pathogens were identified in 83% of 141 AIDS patients with diarrhea, 2% of 53 AIDS patients without diarrhea, and 3% of 56 non-AIDS patients. Microsporidia was the most common pathogen found (39% of AIDS patients with diarrhea). Two or more coexisting infections were found in 28% of AIDS patients with diarrhea. The prevalence rates for coexisting infections were similar to those predicted from the individual prevalence rates, with the exception of cryptosporidiosis and microsporidiosis, which were lower than predicted. Patients with microsporidiosis had severely depressed CD4 lymphocyte counts in peripheral blood. All patients with microsporidiosis, except one, had diarrhea, and D xylose malabsorption was universal in patients with microsporidiosis.

CONCLUSION

Microsporidiosis is a common cause of chronic diarrhea, malabsorption, and weight loss in AIDS patients.

Persisting diarrhoea and malabsorption

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[AIDS as non-suspected cause of chronic diarrhea and malabsorption]

We report a case of chronic diarrhoea resulting in malabsorption syndrome in a patient with AIDS. Diarrhoea started two years before AIDS was diagnosed. The absence of risk factors may have delayed the diagnosis.

Prevalence of intestinal protozoans in French patients infected with HIV

To assess the prevalence of intestinal protozoans in French HIV-infected patients, stool samples, duodenojejunal biopsies, and/or colorectal biopsies from 81 patients were studied for parasites, viruses, and bacteria. Pathogens were found in 70.6% of AIDS patients with diarrhea or malabsorption. The respective prevalence of protozoa in AIDS patients with diarrhea was Cryptosporidium sp.: 37.3%, Blastocystis hominis: 13.7%, Giardia intestinalis: 5.8%, Isospora belli: 2%, Enterocytozoon bieneusi: 2%. Microsporidia were noted in one patient with severe malabsorption but no diarrhea. Other pathogens included cytomegalovirus in 27.4% and Mycobacterium avium in 5.8%. Patients with identified pathogens were more immunosuppressed and more severely malnourished than those with unexplained diarrhea. Multiple pathogens were found in 13 of 81 patients (16%). Twenty-six of 66 identified pathogens (40%) were diagnosed only on biopsy specimens. Chronic diarrhea in HIV patients could be explained in the vast majority by appropriate gastrointestinal investigations. Cryptosporidia played a major role, while microsporidia appeared to be less common.

Malabsorption of vitamin A in preruminating calves infected with Cryptosporidium parvum

Serum retinol, retinyl palmitate, and total vitamin A concentrations, and jejunoileal morphology were examined in neonatal calves infected with Cryptosporidium parvum. Group-1 calves served as noninfected controls and, after an adjustment period, were given 50 ml of saline solution i.v. every 12 hours for 6 days. Group-2 calves were inoculated with 10(7) C parvum oocysts and, after the onset of diarrhea, were given 50 ml of saline solution i.v. every 12 hours for 6 days. Group-3 calves were inoculated with 10(7) C parvum oocysts and, after the onset of diarrhea, were treated with difluoromethylornithine (DFMO, 200 mg/kg of body weight i.v., q 12 h) for 6 days. Group-4 calves were naturally infected with C parvum. Jejunoileal biopsy specimens were excised from calves of groups 1-3 at 3 and again at 15 to 16 days of age. During the course of diarrhea and 3 days after saline or DFMO administration, water-miscible retinyl palmitate was administered orally (2,750 micrograms/kg) to each calf in each group. Cryptosporidium parvum infection was associated with significant (P < or = 0.05) reduction in postadministration serum retinol, retinyl palmitate, and total vitamin A concentrations in calves of groups 2, 3, and 4. Cryptosporidium parvum infection caused significant (P < or = 0.05) reduction in villus height. Decreased villus height, villus blunting and fusion, and attenuation of the intestinal mucosa were associated with reduced absorption of vitamin A, as indicated by lower peak postadministration retinyl palmitate concentration in C parvum-infected calves. Intravenous administration of DFMO to group-3 calves did not improve retinol absorption.(ABSTRACT TRUNCATED AT 250 WORDS)

[Malabsorption syndrome caused by Giardia lamblia in gastrectomized patients]

We report three adult patients with gastrectomy who had malabsorption caused by Giardia lamblia. Type II gastrectomy had been carried out in the three patients several years before, and the clinical presentation was similar: chronic diarrhea with malabsorption. A remarkable fact was that the search for parasites in feces was repeatedly negative in two patients, the protozoon being identified in the intestinal biopsy samples. In the third case, the diagnosis was made by the visualization of Giardia cysts in the feces.

Effect of Eimeria acervulina infection on nutrient retention with special reference to fat malabsorption in chickens

Nutritional balance studies were conducted to determine the effect of Eimeria acervulina infection on the retention of nutrients and the efficiency of utilization of protein and energy in the diet during the course of intestinal coccidiosis in chickens. Both light and electronmicroscopic studies were conducted to elucidate the pathogenesis of fat malabsorption in the infected chickens. The infection with E. acervulina during the acute phase of the disease (day 4 to day 8 postinfection) caused a reduction (P smaller than 0.01) in the retention of percent protein, percent ether extract and percent gross energy of the diet with a concomitant increase (P smaller than 0.01) in the concentration of ether extract and gross energy of the excreta. The metabolizable energy value of the diet was also depressed during this phase. During the recovery phase of the disease (day 9 to day 13 postinfection) infected chickens voided excreta containing a slightly greater concentration of ether extract when compared to the controls but differences in the retention of percent protein and percent gross energy were no longer observed. An increased retention of percent phosphorus also occured during the recovery phase. Studies involving the carcass composition revealed that the efficiency of utilization of protein and metabolizable energy of the diet for tissue deposition was reduced (P smaller than 0.05) during day 0 to day 8 postinfection but only the efficiency of metabolizable energy utilization was found to be depressed (P smaller than 0.05) when data for day 0 to day 14 postinfection were analyzed. Both light and electronmicroscopic studies of the duodenal villi of infected chickens during day 5 to day 6 postinfection revealed accumulation of large globules of fat in the villus epithelial cells parasitized by the gammonts of E. acervulina indicating a possible blackade of "fat exit" from these cells.