A non-encapsulated mutant of <i>C</i>. <i>jejuni</i> is defective in weight loss, diarrhea, and shedding of organism in stool. Panel A.

<p>Weights following infection with either wildtype or 81–176 <i>kpsM</i> in dZD C57Bl/6J male mice. * WT vs <i>kpsM</i>, P<0.05. Diarrhea noted by D. <b>Panel B.</b> qPCR detection of <i>Campylobacter jejuni</i> (<i>cadF</i>) following infection in dZD mice. * WT vs <i>kpsM</i>, P<0.05. (N = 4/group).</p

Metabolic perturbations induced by <i>Campylobacter</i> infection.

<p>Heatmap of the significant metabolic perturbations induced by C.jejuni infection identified by OPLS-DA models. Metabolic shifts are represented as correlation coefficients (r) of infected mice at days 4, 5 and 9 post infection versus diet and age-matched uninfected animals. Red and blue colors indicate increased or decreased excretion of metabolites following C.jejuni challenge respectively. Abbreviations: 2-OIV, 2-oxoisovalerate; 2-OIC, 2-oxoisocaproate; 2-MOV, 3-methyl-2-oxovalerate; 2-PY, N-methyl-2-pyridone-5-carboxamide; 4-CG; 4-cresol glucuronide; 4-CS, 4-cresyl sulfate; 4-HPA, 4-hydroxyphenylacetate; 4-HPPA, 4-Hydroxyphenylpyruvate; 4-PY, N-methyl-4-pyridone-3-carboxamide; DMA, dimethylamine; GAA guanidinoacetate; NAG, N-acetyl glutamine; NMND, N-methylnicotinamide; PAG, phenylacetylglycine; TMA, trimethylamine; TMAO, trimethylamine-N-oxide.</p

Prolonged weight loss following <i>Campylobacter</i> infection.

<p><b>Panel A.</b> Mice fed either HC, or dPD had transient weight loss following infection, but dZD-fed infected mice had significant weight loss (* dZD infected vs uninfected days 2–14 post infection; P<0.001). While mice on dPD showed weight loss with no diarrhea, mice on HC had non-bloody soft stools on days 1–3 post infection, and mice on dZD had persistent bloody diarrhea on days 2–11 post infection. <b>Panel B.</b> Increasing <i>Campylobacter</i> detected in stool for the duration of the experiment (* dZD infected vs HC or dPD infected days 7&11 post infection; P<0.0001). <b>Panel C.</b> Images of stool following <i>Campylobacter</i> infection. Stool collected from HC (images from day 1 and 3 post infection) and dZD fed mice progressed from soft to bloody diarrhea by day 3 post infection (images from day 3 and 7 post infection). (N = 8/group).</p

Intestinal morphometry.

<p>Intestinal sections from dZD fed mice stained for H&E or PAS. <b>Panel A:</b> ileum. <b>Panel B:</b> colon.</p

Correlations between urinary metabolites and inflammatory biomarkers.

<p> Spearman’s correlation heatmap between the urinary metabolites identified in the OPLS-DA models and the levels of inflammatory biomarkers LCN-2 and MPO on day 14 post infection. Only significant correlations following <i>P</i> value adjustment are shown (Benjamini-Hochberg for 5% false discovery rate).</p

Inflammatory biomarkers following <i>Campylobacter</i> infection.

<p>The inflammatory biomarkers myeloperoxidase (MPO) and lipocalin-2 (LCN-2) were measured in cecal contents of antibiotic pretreated mice. LCN-2 was significantly elevated in dZD <i>C</i>. <i>jejuni</i> infected mice on both day 2 and 14 post infection, * dZD infected vs dZD uninfected; P<0.05. MPO was also significantly increased in dZD-fed infected mice on both day 2 and 14 post infection, ** dZD infected vs dZD uninfected; P<0.01.</p

Use of quantitative molecular diagnostic methods to investigate the effect of enteropathogen infections on linear growth in children in low-resource settings: longitudinal analysis of results from the MAL-ED cohort study

Summary: Background: Enteropathogen infections in early childhood not only cause diarrhoea but contribute to poor growth. We used molecular diagnostics to assess whether particular enteropathogens were associated with linear growth across seven low-resource settings. Methods: We used quantitative PCR to detect 29 enteropathogens in diarrhoeal and non-diarrhoeal stools collected from children in the first 2 years of life obtained during the Etiology, Risk Factors, and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development (MAL-ED) multisite cohort study. Length was measured monthly. We estimated associations between aetiology-specific diarrhoea and subclinical enteropathogen infection and quantity and attained length in 3 month intervals, at age 2 and 5 years, and used a longitudinal model to account for temporality and time-dependent confounding. Findings: Among 1469 children who completed 2 year follow-up, 35 622 stool samples were tested and yielded valid results. Diarrhoeal episodes attributed to bacteria and parasites, but not viruses, were associated with small decreases in length after 3 months and at age 2 years. Substantial decrements in length at 2 years were associated with subclinical, non-diarrhoeal, infection with Shigella (length-for-age Z score [LAZ] reduction −0·14, 95% CI −0·27 to −0·01), enteroaggregative Escherichia coli (−0·21, −0·37 to −0·05), Campylobacter (−0·17, −0·32 to −0·01), and Giardia (−0·17, −0·30 to −0·05). Norovirus, Cryptosporidium, typical enteropathogenic E coli, and Enterocytozoon bieneusi were also associated with small decrements in LAZ. Shigella and E bieneusi were associated with the largest decreases in LAZ per log increase in quantity per g of stool (−0·13 LAZ, 95% CI −0·22 to −0·03 for Shigella; −0·14, −0·26 to −0·02 for E bieneusi). Based on these models, interventions that successfully decrease exposure to Shigella, enteroaggregative E coli, Campylobacter, and Giardia could increase mean length of children by 0·12–0·37 LAZ (0·4–1·2 cm) at the MAL-ED sites. Interpretation: Subclinical infection and quantity of pathogens, particularly Shigella, enteroaggregative E coli, Campylobacter, and Giardia, had a substantial negative association with linear growth, which was sustained during the first 2 years of life, and in some cases, to 5 years. Successfully reducing exposure to certain pathogens might reduce global stunting. Funding: Bill & Melinda Gates Foundation