Low levels of faecal lactobacilli in women with iron-deficiency anaemia in south India.

Fe deficiency in women contributes significantly to maternal and child morbidity in India. The intestinal bacterial flora may facilitate absorption of Fe from the caecum and proximal colon. The present study investigated the possibility that intestinal microbiota of anaemic young women may differ from that of women with normal Hb levels. The microbiota was quantified by real-time PCR in faeces of eight anaemic (Hb ≤ 100 g/l) and twenty-six normohaemic (Hb ≥ 120 g/l) women aged 18-25 years. Sequences of 16S ribosomal DNA (rDNA) specific to Bifidobacterium genus, Lactobacillus acidophilus group, Bacteroides-Prevotella-Porphyromonas group, Clostridium leptum group and Eubacterium rectale were amplified and expressed (as relative difference) relative to the universally conserved bacterial 16S rDNA sequences. Dietary intakes of energy, carbohydrate, fibre and Fe were ascertained by maintenance of a diet diary for a week. Faecal lactobacilli were significantly lower in anaemic women (median 6.6 × 10(-8), relative difference compared with total bacteria) than in the reference group (2.9 × 10(-6); P = 0.001, unpaired t test with logarithmic transformation). There was no difference between the two groups with respect to any of the other bacteria that were examined. Intakes of energy, carbohydrate, fibre, Fe and milk were similar in both the groups. Fe deficiency in young women in south India was associated with low levels of lactobacilli in the faeces. The relationship between lactobacilli and Fe deficiency needs to be explored further.

Fecal polymerase chain reaction for Mycobacterium tuberculosis IS6110 to distinguish Crohn's disease from intestinal tuberculosis.

BACKGROUND: We have previously shown that amplification of Mycobacterium tuberculosis specific DNA (TB PCR) from feces reliably diagnosed intestinal tuberculosis. This study was undertaken to determine how well this test would distinguish intestinal tuberculosis from Crohn's disease in a country endemic for tuberculosis. METHODS: Consecutive patients with diagnoses of Crohn's disease and intestinal tuberculosis were enrolled, and the diagnoses confirmed by follow up. DNA was extracted from fecal samples and subjected to polymerase chain reaction TB PCR for IS6110 sequence which is specific for M. tuberculosis. RESULTS: Twenty one of 24 patients with intestinal tuberculosis and 5 of 44 patients with Crohn's disease tested positive by TB PCR. The sensitivity, specificity, positive predictive and negative predictive values for TB PCR in distinguishing tuberculosis from Crohn's disease were 0.79 (95% confidence interval 0.57-0.92), 0.88 (0.75-0.96), 0.79 (0.57-0.92) and 0.88 (0.75-0.96), respectively. A combination of fecal TB PCR with mycobacterial culture of mucosal biopsy specimens identified 23 of 24 (96.2%) of patients with intestinal TB, with sensitivity, specificity, positive predictive and negative predictive values (95% CI) of 0.95 (0.78-0.99), 0.88 (0.75-0.96), 0.82 (0.63-0.93) and 0.97 (0.86-0.99), respectively. CONCLUSION: Fecal TB PCR is a good screening test to distinguish intestinal tuberculosis from Crohn's disease.

Bacterial succession in the colon during childhood and adolescence: molecular studies in a southern Indian village.

BACKGROUND: The colonic bacterial flora, largely anaerobic, is believed to establish and stabilize in the first 2 y of life. OBJECTIVE: This study was undertaken to determine whether the bacterial flora of the colon undergoes further changes (succession) during childhood and adolescence. DESIGN: This cross-sectional study examined fecal samples from 130 healthy children and adolescents in the age group 2-17 y and from 30 healthy adults (median age: 42 y) residing in a single village in southern India. DNA was extracted and subjected to 16S rDNA-targeted real-time polymerase chain reaction to determine the relative predominance of Bifidobacterium genus, Bacteroides-Prevotella-Porphyromonas group, Lactobacillus acidophilus group, Eubacterium rectale, and Faecalibacterium prausnitzii. RESULTS: Bifidobacterium species and Bacteroides-Prevotella group were dominant fecal bacteria overall. E. rectale and Lactobacillus species were considerably less abundant. Clear age-related differences emerged, with a steep decline in Bifidobacterium species in adults (P < 0.0001), a steep decline of Lactobacillus species >5 y of age (P < 0.0001), an increase in Bacteroides during late adolescence and in adults (P = 0.0040), an increase in E. rectale during childhood and adolescence followed by a steep decline in adults (P < 0.0001), and a late childhood peak of F. prausnitzii with decline in adolescents and adults (P < 0.0001). CONCLUSIONS: Changes in the bacterial flora occur during childhood and adolescence characterized by reduction in Lactobacillus and Bifidobacterium species and an increase in Bacteroides, E rectale, and F. prausnitzii peaked during late childhood in this population.