Spectrum and antibiotic sensitivity of bacteria contaminating the upper gut in patients with malabsorption syndrome from the tropics.

BACKGROUND: Various causes of malabsorption syndrome (MAS) are associated with intestinal stasis that may cause small intestinal bacterial overgrowth (SIBO). Frequency, nature and antibiotic sensitivity of SIBO in patients with MAS are not well understood. METHODS: Jejunal aspirates of 50 consecutive patients with MAS were cultured for bacteria and colony counts and antibiotic sensitivity were performed. Twelve patients with irritable bowel syndrome were studied as controls. RESULTS: Culture revealed growth of bacteria in 34/50 (68%) patients with MAS and 3/12 controls (p < 0.05). Colony counts ranged from 3 x 10(2) to 10(15) (median 10(5)) in MAS and 100 to 1000 (median 700) CFU/ml in controls (p 0.003). 21/50 (42%) patients had counts GreaterEqual;105 CFU/ml in MAS and none of controls (p < 0.05). Aerobes were isolated in 34/34 and anaerobe in 1/34. Commonest Gram positive and negative bacteria were Streptococcus species and Escherichia coli respectively. The isolated bacteria were more often sensitive to quinolones than to tetracycline (ciprofloxacin: 39/47 and norfloxacin: 34/47 vs. tetracycline 19/47, <0.01), ampicillin, erythromycin and co-trimoxazole (21/44, 14/22 and 24/47 respectively vs. tetracycline, p = ns). CONCLUSIONS: SIBO is common in patients with MAS due to various causes and quinolones may be the preferred treatment. This needs to be proved further by a randomized controlled trial.

Etiological spectrum of sporadic malabsorption syndrome in northern Indian adults at a tertiary hospital.

BACKGROUND: The etiology of malabsorption syndrome (MAS) may differ in different geographical regions. Limited data are available on the etiological spectrum of MAS among Indian adults. METHODS: Ninety-nine consecutive adult patients with MAS (urine d-xylose <1 g/5 g/5 h with or without increased fecal fat (> or =7 g/24 h) were evaluated for cause of MAS using standard criteria. Past medical records were examined to know the nature of treatment received. RESULTS: The etiology of MAS was: tropical sprue 39, celiac disease 9, Crohn's disease 9, giardiasis 8, small intestinal bacterial overgrowth in absence of another cause of MAS 8, panhypogammaglobulinemia 2 (one with strongyloidiasis), intestinal lymphangiectasia 1, intestinal tuberculosis 4, idiopathic 15, acquired immunodeficiency syndrome 2, and amyloidosis 2. Twenty-eight patients had received anti-tubercular treatment earlier. CONCLUSIONS: Tropical sprue, celiac disease and Crohn's disease are common causes of MAS in Indian adults. Inappropriate anti-tubercular treatment is common in them and needs to be discouraged.

Evidence for activation of cellular immune responses in patients with acute hepatitis E.

INTRODUCTION: Although acute hepatitis E virus (HEV) infection is known to induce IgM and IgG humoral host immune responses, little is known about occurrence of cellular responses in this infection. We looked for evidence of lymphocyte sensitization to HEV peptides in patients with acute HEV infection. METHODS: peripheral blood lymphocytes were obtained from patients with acute hepatitis E and healthy controls. Proliferation of these lymphocytes in the presence of each of seven peptides with amino acid sequences corresponding to open reading frames 2 and 3 proteins of HEV (3 and 4 peptides, respectively) were studied; no peptide was added to control wells. Proliferative responses with stimulation indices exceeding 3.0 were taken as positive. RESULTS: More patients showed reactivity to two or more HEV peptides than did controls (11/21 vs 5/22, p<0.05). Reactivity to one peptide corresponding to open reading frame 2 of HEV was more frequent in patients than in controls (7/21 vs 1/22, p<0.05). CONCLUSION: Our results show that lymphocytes of patients with acute hepatitis E show sensitization to HEV peptides. This may have significance in understanding the pathogenetic mechanisms of liver injury in this infection.

Occult hepatitis B virus infection as a cause of cirrhosis of liver in a region with intermediate endemicity.

BACKGROUND: Serological tests may fail to identify hepatitis B virus (HBV) infection as a cause of liver cirrhosis in a proportion of patients. The frequency of such occult infection in regions with intermediate HBV endemicity is not known. Such cases may be diagnosed by incremental testing for IgG anti-HBc, serum HBV DNA, and HBV DNA in liver tissue. METHODS: We tested sera of 111 patients with cirrhosis, including 39 with history of significant alcohol ingestion, for HBsAg, anti-HBc and serum HBV DNA. In addition, in a subset of 14 patients, HBV DNA was looked for in liver tissue. RESULTS: On HBsAg and anti-HBc testing, 66 patients had HBV infection. Serum HBV DNA testing identified HBV infection in 13 additional cases. Of 18 patients labeled as 'cryptogenic' on serological testing, HBV DNA was detected in the serum in 7 patients. Of 14 patients in whom paired liver tissue and serum specimens were tested, 4 additional patients with HBV infection were detected after liver biopsy analysis. CONCLUSIONS: Serological tests for HBsAg and anti-HBc antibody are insensitive in identifying HBV infection in patients with liver cirrhosis. HBV DNA testing in serum and liver can help in establishing HBV infection as etiology, either alone or in addition to another cause.

Immunological alterations in pregnant women with acute hepatitis E.

BACKGROUND: Infection with hepatitis E virus (HEV) is a major cause of acute viral hepatitis in several developing countries. Although usually self-limiting and benign, the disease is particularly severe among pregnant women, with mortality rates reaching 15-20%. METHODS: Immune parameters among pregnant women with acute hepatitis E (P-HEV) were investigated and compared with those in non-pregnant patients with hepatitis E (N-HEV), and healthy pregnant (PC) and non-pregnant (NPC) women. RESULTS: Peripheral blood mononuclear cells (PBMC) from P-HEV patients had lower lymphocyte proliferation response to phytohemagglutinin (PHA) than those in the PC and NPC groups. A positive lymphocyte proliferation response to HEV antigen (HEVAg), a mixture of eight peptides derived from HEV proteins, was observed in 7/19 (37%) P-HEV patients, 3/9 (33%) N-HEV patients and only 2/21 (10%) PC and 2/14 (14%) NPC subjects; the stimulation indices in the P-HEV group were similar to the N-HEV group and higher than the PC group. Measurement of cytokine production by PBMC in response to PHA and HEVAg showed a reduction in production of T-helper 1 (Th1) cytokines and an increase in that of Th2 cytokines in the P-HEV group. Cytokine mRNA levels showed similar changes. CONCLUSION: These results show the existence of a Th2 bias in pregnant women with acute hepatitis E. The role of this Th2 bias in the greater severity of hepatitis E among pregnant women needs further investigation.

Ambulatory esophageal pH monitoring: technique, interpretations, and clinical indications.

Gastroesophageal reflux disease (GERD) is the most common esophageal disorder and perhaps among the most prevalent conditions seen in the primary care setting. The clinical manifestations of GERD, typical or atypical, such as noncardiac chest pain, respiratory or ear, nose, and throat symptoms, result from the reflux of gastric contents into the esophagus. Thus the clinical spectrum is wide and requires accurate diagnosis. Ambulatory 24-hr esophageal pH monitoring is not useful in all patients suspected to have GERD. This review describes the technique of ambulatory 24-hr esophageal pH monitoring, the interpretation of findings, and clinical applications of this test.

Assessment of cost-effectiveness of universal hepatitis B immunization in a low-income country with intermediate endemicity using a Markov model.

BACKGROUND/AIMS: Most countries with high hepatitis B (HB) virus endemicity and most high-income countries have introduced immunization programmes against this infection. However, several low-income countries with intermediate HB endemicity have not done so. We performed a cost-effectiveness analysis of universal childhood HB immunization in such countries using India as an example, since available data on this aspect are limited. METHODS: Marginal cost of every life-year and quality-adjusted life-year (QALY) gained with universal HB vaccination was calculated using a Markov model. Two types of analyses (including and excluding expenditure on treatment of long-term complications of HB infection) were done. Several sensitivity analyses and Monte-Carlo simulation were performed. RESULTS: Universal immunization reduced the HB carrier rate by 71%, and increased the number of years and QALY lived by a birth-cohort by 0.173 years (61.072 vs. 60.899 years) and 0.213 years (61.056 vs. 60.843 years), respectively. Marginal costs were US$16.27 per life-year gained and US$13.22 per QALY gained, much lower than annual per capita income. One-way sensitivity analysis and Monte-Carlo simulation confirmed the robustness of the conclusions. CONCLUSIONS: Universal HB immunization is highly cost-effective in low-income countries with intermediate endemicity rates.

Strongyloides stercoralis infestation associated with septicemia due to intestinal transmural migration of bacteria.

Strongyloides stercoralis infestation is common in the tropics and is usually asymptomatic. Patients with immunocompromised states may develop hyperinfection and fulminant disease. It has been suggested that bacteria accompany S. stercoralis during its passage across the bowel wall, resulting in systemic sepsis. Herein is a report on a 30-year-old man with S. stercoralis infestation and small bowel bacterial overgrowth presenting as malabsorption syndrome. He developed extensive duodenojejunal ulceration, septicemia and fatal hypokalemia. Blood and jejunal fluid grew Escherichia coli with the same antibiotic sensitivity patterns. This supports the hypothesis of migration of bacteria from the intestinal lumen as a cause of septicemia in patients with fulminant S. stercoralis infestation.

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.