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.

Current spectrum of malabsorption syndrome in adults in India.

AIM: Tropical sprue was considered to be the most important cause of malabsorption in adults in India. However, several reports indicate that celiac disease is now recognized more frequently. METHODS: We analyzed the clinical presentation, endoscopic and histological features of 94 consecutive patients (age >12 years) with chronic diarrhea and malabsorption syndrome. The spectrum of disease in these patients and features differentiating celiac disease and tropical sprue are reported here. RESULTS: Celiac disease (n = 61, 65%) was the most common cause of malabsorption followed by tropical sprue (21, 22%). Other conditions including cyclosporiasis (3), Crohn's disease (2), common variable immunodeficiency (2), lymphangiectasia (1), William's syndrome (1), and idiopathic malabsorption (3) accounted for the remainder. A greater number (21, 34%) of patients with celiac disease than those with tropical sprue (4, 19%) presented with atypical manifestations. Patients with celiac disease were younger (p = 0.001), more often had anemia, (p = 0.001), scalloping of folds (p = 0.001), moderate (p = 0.02) or severe (p = 0.001) villous atrophy, higher grade of intraepithelial lymphocytic infiltration (p = 0.001), crypt hyperplasia (p = 0.001), cuboidal (p = 0.001) and pseudostratified (p = 0.009) surface epithelial cells, and diffuse (p = 0.001) epithelial damage. In comparison, patients with tropical sprue were older and more often had normal duodenal folds, normal villi, tall columnar epithelial cells and focal epithelial damage. CONCLUSIONS: Celiac disease was the most frequent cause of malabsorption syndrome in this series of patients. There are significant clinical and histological differences between celiac disease and tropical sprue.

Effect of Cryptosporidium parvum infection on the absorptive capacity and paracellular permeability of the small intestine in neonatal calves.

Cryptosporidium parvum is recognized as one of the most important pathogens causing enteritis and severe diarrhoea in calves up to 1 month of age. Although the infection may be responsible for some mortality, its impact is mainly associated with the impairment of intestinal functions and lower performance of animals. The aim of this study was to determine the effect of cryptosporidiosis on the intestinal functions in neonatal experimentally infected Holstein calves. Absorption tests with d-xylose and retinyl-palmitate, and the lactulose/mannitol test of intestinal permeability were simultaneously performed in 1-week intervals from challenge to full recovery. In infected animals, reduced intestinal absorptive capacity for both D-xylose and retinyl-palmitate was observed on day 7 post-infection (p.i.). At the same time, a more than 100% elevation of intestinal permeability was observed in the infected calves. All intestinal functions, except absorption of retinyl-palmitate, were significantly affected and changes were detected up to day 14 p.i. In contrast, results of all tests obtained on day 21 p.i. suggest full recovery of the infected intestine. Significantly, growth of the calves which had recovered from cryptosporidiosis was still affected between days 14 and 21 p.i.

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.

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.

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.

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.

[AIDS as non-suspected cause of chronic diarrhea and malabsorption]. / El SIDA como causa insospechada de diarrea crónica y malabsorción.

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.