lactoferrin and Cryptosporidiosis

Cryptosporidium is an important cause of infectious diarrhoea worldwide, but little is known about the course of illness when infected with different species. Over a period of 5 years, Cryptosporidium was identified in the stools of 58 of 157 children prospectively followed from birth in an urban slum (favela) in northeast Brazil. Forty isolates were available for quantification and 42 for speciation (24 Cryptosporidium hominis and 18 C. parvum). Children with C. hominis shed significantly more oocysts/ml of stool (3.5 x 10(6) vs. 1.7 x 10(6)perml; P=0.001), and oocyst counts were higher among symptomatic children (P=0.002). Heavier C. parvum shedding was significantly associated with symptoms (P=0.004), and symptomatic C. parvum-infected children were significantly more likely than asymptomatic children to be lactoferrin-positive (P=0.004). Height-for-age (HAZ) Z-scores showed significant declines within 3 months of infection for children infected with either C. hominis (P=0.028) or C. parvum (P=0.001). However, in the 3-6 month period following infection, only C. hominis-infected children continued to demonstrate declining HAZ score and asymptomatic children showed even greater decline (P=0.01). Cryptosporidium hominis is more common than C. parvum in favela children and is associated with heavier infections and greater growth shortfalls, even in the absence of symptoms.

Topics: Animals; Anthropometry; Child, Preschool; Cryptosporidiosis; Cryptosporidium; Cryptosporidium parvum; Diarrhea, Infantile; Feces; Host-Parasite Interactions; Humans; Infant; Lactoferrin; Nutritional Status; Polymerase Chain Reaction; Polymorphism, Restriction Fragment Length; Prospective Studies; Species Specificity; Urban Health

In the present study, the prevalence and species distribution of Cryptosporidium among school children and hospital patients in the Venda region of South Africa was determined. Real time PCR (qPCR) was used for initial screening to detect positive samples while a nested PCR followed by restriction fragment length polymorphism was used to determine the species genotype. From a total of 244 stool samples tested, 44 (18%) had Cryptosporidium with no significant difference (chi(2)=0.04; P=0.841) between samples collected from patients attending hospitals 36/197 (18%) and the samples from primary schools 8/47 (17%). The age groups most affected were those from 2 to 5 years old (28.6%) and 50 to 59 years old (50.0%). Cryptosporidium was detected in 4 (12.5%) of the 31 HIV positive individuals. Fifty-seven percent of the Cryptosporidium positive samples were diarrheic and 26 (59.1%) had elevated lactoferrin content. C. hominis (82%) was more common than C. parvum (18%). This study has demonstrated the high prevalence of Cryptosporidium infections in the Venda region and its implications in causing diarrhea and inflammation.

Topics: Adolescent; Adult; Age Distribution; Aged; Aged, 80 and over; Animals; Child; Child, Preschool; Cryptosporidiosis; Cryptosporidium; Feces; Female; Genotype; HIV Infections; Hospitalization; Humans; Infant; Lactoferrin; Male; Middle Aged; Polymerase Chain Reaction; Polymorphism, Restriction Fragment Length; Schools; Sex Distribution; South Africa

To examine the importance of intestinal inflammation in the diagnosis and pathogenesis of human cryptosporidiosis, stools of healthy adult volunteers before and after experimental infection were tested for fecal lactoferrin, interleukin-8 (IL-8), and tumor necrosis factor-alpha (TNF-alpha). Stool samples of Brazilian children with well-defined Cryptosporidium infection, with or without diarrhea, were also tested for IL-8 and TNF-alpha. Only one of the 14 volunteers challenged with Cryptosporidium had increased fecal lactoferrin. However, of 17 stool specimens from children with only Cryptosporidium infection from a previous study, 12 had mild to moderately elevated lactoferrin despite negative work-up for inflammatory enteritides. One of 10 adult volunteers who developed diarrhea with experimental cryptosporidiosis and three of 11 children with cryptosporidiosis and diarrhea had detectable fecal IL-8. The level of TNF-alpha was increased only in one of 14 volunteers and in none of the children. Although considered relatively non-inflammatory. cryptosporidiosis is often associated with mild inflammation, especially in children in an endemic area.

Topics: Adult; Case-Control Studies; Child; Cryptosporidiosis; Humans; Immunocompetence; Interleukin-8; Lactoferrin; Tumor Necrosis Factor-alpha

The mechanisms by which Cryptosporidium parvum cause persistent diarrhea and increased morbidity and mortality are poorly understood. Three groups of Haitian children <18 months old were studied: case patients, children with diarrhea not due to Cryptosporidium, and healthy control subjects. Compared with both control groups, children with acute cryptosporidiosis were more malnourished (including measures of stunting [P=.03] and general malnutrition [P=.01]), vitamin A deficient (P=.04), and less often breast-fed (P=.04). Markers of a proinflammatory immune response, interleukin (IL)-8 and tumor necrosis factor-alpha receptor I, were significantly elevated in the case population (P=.02 and P<.01, respectively), as was fecal lactoferrin (P=.01) and the T helper (Th)-2 cytokine IL-13 (P=.03). The counterregulatory cytokine IL-10 was exclusively elevated in the case population (P<.01). A Th1 cytokine response to infection was not detected. This triple cohort study demonstrates that malnourished children with acute cryptosporidiosis mount inflammatory, Th-2, and counterregulatory intestinal immune responses.

Topics: Animals; Breast Feeding; Cohort Studies; Cryptosporidiosis; Cryptosporidium parvum; Developing Countries; Diarrhea; Feces; Haiti; Humans; Infant; Interleukin-10; Interleukin-13; Interleukin-8; Intestines; Lactoferrin; Nutrition Disorders; Prospective Studies; Proteins; TNF Receptor-Associated Factor 1; Urban Population; Vitamin A Deficiency