Chronic infections of the small intestine.

PURPOSE OF REVIEW: Chronic infections of the small intestine cause significant morbidity and mortality globally. This review focuses on the recent advances in the field of our understanding of selected intestinal infections. RECENT FINDINGS: Primary and secondary immunodeficiency increase the susceptibility to many chronic intestinal infections. Endoscopy and intestinal biopsies are central to establishing a diagnosis of these conditions. Tuberculosis (TB) remains a major global health challenge. Emerging therapeutic agents to counteract multidrug-resistant strains have shown clinical efficacy, but concerns regarding mortality remain. PCR-based diagnostic TB tests have the potential to reduce diagnostic delays, but remain to be validated for intestinal infections. Adjunctive diagnostic imaging modalities can differentiate infections from Crohn's disease with increasing accuracy. Whipple's disease remains rare, but there have been substantial advances in our understanding of the causative organism Tropheryma whipplei. Extended treatment with broad-spectrum antibiotics is effective in most cases. The narrow therapeutic window and limited armamentarium for treating invasive filamentous fungal infections contribute to their significant morbidity and high rates of mortality. SUMMARY: The speed and accuracy of diagnosing chronic intestinal infections have improved with recent imaging and laboratory methodologies. Significant research opportunities remain for clinicians and scientists to improve the diagnostic accuracy and clinical outcomes of chronic intestinal infections.

Abnormal small intestinal permeability in patients with idiopathic malabsorption in tropics (tropical sprue) does not change even after successful treatment.

BACKGROUND: Though tropical sprue (TS) is common in tropics, studies on small intestinal permeability (SIP) in TS are scant. METHOD: SIP was evaluated using (1)H nuclear magnetic resonance (NMR) spectroscopy of urinary lactulose and mannitol in 24 patients with TS (22 before and 15 after treatment with tetracycline and folate) and in 31 healthy subjects (HS). Effect of treatment of TS on SIP and its relationship with outcome were studied. RESULT: Subjects were comparable in terms of age and gender. Before treatment, urinary lactulose (0.24 mmol, 0-1.09 mmol versus 0.09 mmol, 0-0.68 mmol, P=0.02) and lactulose-to-mannitol (L/M) ratio (0.11, 0-0.41 versus 0.042, 0-0.26, P=0.001) were higher in TS than in HS, though mannitol was comparable (2.7 mmol, 0.61-10.5 mmol versus 3.8 mmol, 1.3-16.4 mmol, P=0.08). Patients improved after treatment [stool frequency (9, 4-20/day versus 1, 1-2/day, P<0.0001), weight (44.4, 32-69 kg, versus 56, 39-84 kg, P<0.0001), fecal fat (10.1, 6-26 g/24 h versus 4.4, 3.0-6.7 g/24 h, P<0.0001), D-xylose (0.57, 0.28-1.2 g/5 g/5 h versus 1.1, 0.2-2.1 g/5 g/5 h, P<0.0001), and small intestinal bacterial overgrowth (SIBO) resolved in 10/24 (41.7%) versus 1/15 (6.6%), P=0.02]. Though urinary lactulose (0.17, 0-4.3 mmol versus 0.09, 0-0.68 mmol, P=0.11) and mannitol (2.17, 0.8-36.7 mmol versus 3.84, 1.3-16.4 mmol, P=0.06) were comparable, L/M ratio was higher in TS than in HS (0.09, 0-0.22 versus 0.042, 0-0.26, P=0.002). L/M ratio was more often abnormal (cutoff 0.078) in TS than in HS [14/22 (63.6%) versus 3/31 (9.7%); P=0.0001], which persisted even after treatment [9/15 (60%) as compared with HS; P=0.0006]. Persistently abnormal SIP was associated with less weight gain and frequent stools following treatment. CONCLUSION: SIP is often abnormal in TS and remains unchanged even after successful treatment that was associated with less weight gain and more frequent stool.

Tropical sprue.

Tropical sprue (TS) is a clinical entity of unknown etiology characterized by an acquired chronic diarrheal illness and malabsorption that affects indigenous inhabitants and expatriates, either long-term residents or short-term visitors, in the tropical countries. The exact pathogenetic sequence of TS remains incompletely characterized. Bacterial overgrowth, disturbed gut motility, and hormonal and histopathologic abnormalities contribute to the development of TS in a susceptible host. Treatment with tetracycline and folate is effective in some patients, although relapses after treatment are common. Research in the areas of microbial factors, pathogenesis, immunogenetics, and hormonal and immune regulation, using modern diagnostic techniques, may be able to settle some of the unanswered issues and open new venues for diagnosis, prevention, and treatment of tropical sprue.

Tropical sprue: revisited.

OBJECTIVE: To review the experience of patients presenting with clinical manifestations of tropical sprue and assess their diagnosis and management, response to treatment and follow up. METHODS: This single center retrospective descriptive study was done at Shifa International Hospital, Islamabad from January 1994 to January 2003. All patients who presented with diarrhea, anorexia, weight loss and anemia and who proved to have partial villous atrophy on intestinal biopsy and had responded to treatment with antibiotic and folic acid,were included in this review. RESULTS: A total of 42 patients were encountered during these years. There were 31 (74.0%) males and 11 (26%) females. The age ranged from 17-66 years. All patients presented with diarrhea, weight loss, anorexia and had megaloblastic anemia. In all patients, a distal duodenal biopsy showed partial villous atrophy. All were treated with tetracycline 1 g per day and folic acid 5 mg per day and responded to treatment within 4 weeks. Total treatment lasted 3 months and resulted in complete resolution of symptoms and gain of weight. The follow up lasted for a mean of 5 years and no relapses were noted. CONCLUSION: Tropical sprue presents with diarrhea, anorexia, weight loss, and megaloblastic anemia. The partial villous atrophy has been a constant finding. The response to treatment to tetracycline and folic acid has been uniformly successful.

Tropical sprue is associated with contamination of small bowel with aerobic bacteria and reversible prolongation of orocecal transit time.

BACKGROUND: In tropical sprue (TS), response to antibiotics may suggest a role for bacterial contamination of the small bowel, which is known in diseases with prolonged orocecal transit time (OCTT). METHODS: We studied 13 patients with TS (diagnosed by standard criteria) for frequency, nature and degree of bacterial contamination of the small bowel by quantitative culture of jejunal aspirate, glucose hydrogen breath test (GHBT), and OCTT by lactulose hydrogen breath test before and after treatment. Twelve patients with constipation-predominant irritable bowel syndrome (IBS) and 12 healthy subjects served as controls. RESULTS: Ten of 13 patients with TS had bacterial contamination compared with 3/12 with IBS (all aerobic, P < 0.05). Median colony count in TS (36 000 CFU/mL, 400 to > 100 000) was higher than IBS (700 CFU/mL, 100-1000, P < 0.05). Gram-negative aerobic bacilli were commonly isolated in TS but not in IBS. Median OCTT was longer in TS (180 m, 40 - 240) than IBS (110 m, 70 - 150, P = 0.008) and healthy subjects (65 m, 40 - 110, P = 0.0007, Wilcoxon rank sum test). Orocecal transit time in TS correlated with fecal fat (Spearman's rank correlation coefficient 0.69, P < 0.05). Orocecal transit time and fecal fat, repeated in 8/13 patients, decreased with treatment for TS (195 m, 130-240 vs 125 m, 90-200, P = 0.02; 8 g/24 h, 6.8-19.6 vs 7 g/24 h, 4.2-9, P = 0.04, respectively). CONCLUSION: Aerobic bacterial contamination of the small bowel is common in patients with TS. Prolonged OCTT in TS correlated with fecal fat and normalized in a subset of patients after treatment.

[Chronic diarrhea after a journey to Sri Lanka]. / Chronische Diarrhö nach Aufenthalt in Sri-Lanka.

A 51-year-old woman was referred for evaluation of chronic diarrhea. She had spent a 14 day vacation in Sri Lanka three years ago. The clinical examination of the patient was unremarkable. Values for protein, iron, zinc, copper and folic acid were decreased and the Shilling- and D-xylose tests revealed pathological results. Gliadin and Endomysium antibodies were not detectable. Histologic examination of the duodenum displayed chronic duodenitis with increased epithelial regeneration and villous atrophy. In the MRI a segment of the mid small bowel with increased thickness of the intestinal wall was described. Abdominal CT-scans demonstrated multiple, enlarged mesenteric lymph nodes. Laparoscopy with biopsies of the ileum and mesenteric lymph nodes excluded a malignant lymphoma, mycobacteriosis or Whipple's disease. Oral therapy with tetracyclines (250 mg q. i. d.) and substitution of folic acid and iron led to rapid improvement of the clinical symptoms which persisted after cessation of the antibiotic therapy. In view of the clinical course tropical sprue has to be assumed despite the short duration of the journey to a tropical region.

[Tropical sprue]. / Esprue tropical.

We report the case of a 60 year old female who presented with diarrhoea and malabsorption syndrome, confirmed by the laboratory data and the radiologic examination, which developed after a journey to Egypt. The mainly finding was flattening of the villi in the jejunal biopsy; the syndrome recovered after treatment with antibiotics and folic acid. The case fulfills the diagnostic criteria of tropical sprue although this country is not considered as an endemic area.

Tropical sprue in American servicemen following return from Vietnam.

Moderately severe tropical sprue was diagnosed in two American servicemen 15 and 19 months after return from Vietnam. Intestinal parasites were not demonstrated, and clinical, laboratory, and jejunal histological abnormalities returned to normal following treatment with tetracycline and folic acid in one patient and folic acid alone in the other. Neither patient was anemic, although one had hypersegmented polymorphonuclear leukocytes and both had macrocytosis and megaloblastic bone marrows. In each of these patients, diagnosis was delayed because of the failure to consider tropical sprue in the differential diagnosis of diarrhea and weight loss. The findings in these patients indicate that individuals from nonendemic areas who reside in Vietnam are at risk of developing overt tropical sprue.

Bacterial colonisation of jejunal mucosa in acute tropical sprue.

Fifteen of sixteen Caucasians with acute tropical sprue were founc to have numerous aerobic bacteria closely associated with the mucosal layer of the proximal jejunum. Four species of Enterobacteria were grown in eleven patients, and concentrations were higher in the mucosal patients than in the jejunal fluid. Only one of eight control cases with similar tropical exposure but without mucosal morphological abnormalities had any similar bacteria in the mucosal biopsy. In no case were Bacteroides isolated. Since clinical and biochemical improvement only occurred on treatment with tetracycline when enterobacteria were eliminated from the mucosa, it is suggested that these organisms may be responsible for persisting jejunal abnormalities in tropical sprue.