Evaluation of the ProSpecT Microplate Assay for detection of Campylobacter: a routine laboratory perspective.

OBJECTIVES: To evaluate the use of the new enzyme-linked immunosorbent assay, the ProSpecT Campylobacter Microplate Assay (Alexon-Trend, Minneapolis, MN, USA), which allows 2-h detection of both Campylobacter jejuni and Campylobacter coli antigen directly in stool specimens. METHODS: Over 4 months, all stool samples preserved in Cary-Blair medium, or fresh specimens, from non-hospitalized children and HIV-infected patients (adults and children), submitted to our laboratory were evaluated with the ProSpecT Campylobacter Microplate Assay. Results were compared with those obtained by routine culture methods using both a specific medium and a filtration method for the recovery of Campylobacter spp. RESULTS: Of the 1205 stool specimens cultured, 101 were found to be positive for either C. jejuni or C. coli, giving an overall recovery rate of 8.38%. Ninety samples were positive by both culture and ProSpecT Campylobacter Microplate Assay, and 11 were positive by culture only, giving a sensitivity of 89.1%. In addition, of 1104 samples negative by culture, 25 were initially positive by ProSpecT Campylobacter Microplate Assay. We found no cross-reaction with other bacterial enteropathogens isolated from stool specimens. These results thus confirm a high specificity (97.7%) for both C. jejuni and C. coli. The positive and negative predictive values found were 78.3% and 99%, respectively. There was no statistically significant difference in sensitivity and specificity if the stool was fresh or preserved with Cary-Blair medium. CONCLUSION: These data suggest that the ProSpecT Campylobacter Microplate Assay is a rapid and easy-to-use test for the detection of both C. jejuni and C. coli in stool specimens. It could be used for patients for whom early antibiotic therapy is needed or for epidemiologic studies.

Community-acquired bacteremia among hospitalized children in rural central Africa.

OBJECTIVE: To describe the epidemiology of community-acquired bacteremia in children admitted to a rural hospital in central Africa and to identify useful diagnostic signs or symptoms. METHODS: On admission, a blood culture was obtained from all children admitted to Children's Hospital of Lwiro between 1989 and 1990. Clinical and biologic signs of infection and nutritional status were recorded. RESULTS: Among the 779 children included in the study, 15.9% were bacteremic on admission. The rate of bacteremia was the highest among children with jaundice (20/56; 35.7%) and fever (119/487; 24.4%). In contrast, children with severe malnutrition had a lower rate of bacteremia (13.2%) than weight growth retarded or well-nourished children (19.5%) (P = 0.046). Fever was the most useful diagnostic criteria (sensitivity and negative predictive value of 96.0% and 97.8%, respectively) even in severely malnourished children (sensitivity and negative predictive value of 96.4% and 99.1%, respectively). Enterobacteriacea, mostly Salmonella spp, caused 73% of the bacteremia. There was a high rate of resistance to ampicillin and chloramphenicol among the responsible organisms. Only 31 (47.7%) of 65 bacteremic children responded to the combination of ampicillin and gentamicin. The presence of bacteremia on admission did not significantly increase the risk of morality during hospitalization (19.4% compared with 13.5%; P = 0.088). Age less than 12 months and jaundice were independent risk factors for deaths in bacteremic children. CONCLUSIONS: Community-acquired bacteremia caused by multiresistant Enterobacteriacea is an important problem of hospitalized well-nourished and malnourished children in central Africa. Fever on admission is a sensitive diagnostic sign, even in malnourished children.

Congenital hypothyroidism and neonatal withdrawal syndrome.

UNLABELLED: We describe a neonate born of drug dependent parents. This observation documents the variability of expression in the neonatal abstinence syndrome and the interaction with an additional disease. CONCLUSION: The neonatal abstinence syndrome was masked by congenital hypothyroidism until thyroxine treatment had normalised cellular metabolism.

Significance of very low retinol levels during severe protein-energy malnutrition.

In developing countries, severe vitamin A deficiency is associated with increased child mortality. In Kivu, Zaïre, child mortality rate is approximately 50 per 1000 per year and protein calorie malnutrition is endemic. To evaluate vitamin A status in this population, we measured plasma retinol levels in 28 severely malnourished hospitalized children (plasma albumin level below 3 g/dl), and in 153 outpatients (mean plasma albumin level: 3.19 +/- 0.7 g/dl) as controls. Sixty percent of inpatients and 37 percent of out-patients had retinol levels below 10 micrograms/dl (P = 0.02) suggesting a high prevalence of severe vitamin A deficiency in this population. We found that plasma retinol levels were correlated with low retinol binding protein plasma levels (r = 0.77). We conclude that although vitamin A deficiency probably exists in this malnourished population, low retinol levels could at least partly be related to decreased levels of its carrier protein.

The prevalence of Helicobacter pylori positivity in human immunodeficiency virus-infected children.

To investigate the prevalence of Helicobacter pylori infection in pediatric patients infected with the human immunodeficiency virus, we sought to detect the presence of antibodies against this organism in 23 human immunodeficiency virus-infected children of central African ethnic origin by means of a second-generation enzyme-linked immunoassay (ELISA) test for the detection of immunoglobulin G (IgG) antibodies to Helicobacter pylori (Malakit Helicobacter pylori, Biolab, Limal, Belgium). They were compared to an asymptomatic control population matched for age and ethnic origin. Blood samples were taken during routine blood analysis before the monthly administration of intravenous gamma-globulins in the human immunodeficiency virus-infected patients and during preoperative blood analysis in the control population. Despite the fact that most human immunodeficiency virus-infected patients had IgG antibodies against other frequently encountered pathogens, none of them had a positive serology for Helicobacter pylori, compared to 10 of 52 patients (19.2%) in the control population. This difference is statistically significant (p = 0.01).

Biological risk factors for fatal protein energy malnutrition in hospitalized children in Zaire.

Biological markers were used in an attempt to predict mortality in children admitted to the hospital in Kivu, Zaire, for protein energy malnutrition. Data for 39 children who died (16.4%) showed significantly lower levels of albumin (1.61 vs. 2.53 g/dl; p < 0.001), transferrin (82.1 vs. 167.7 mg/dl; p < 0.001), and transthyretin (6.49 vs. 9.87 mg/dl; p < 0.001), but not or retinol-binding protein, than for the 199 survivors. Since albumin and transferrin were correlated, a Cox model was used to see whether albumin or transferrin has a significant predictive value independent of transthyretin. The relative risk predicted by each indicator was of the same order of magnitude, approximately 4. We conclude that specific biological markers help to discriminate among hospitalized subjects at risk and to identify those in need of more intensive nutritional support to prevent early death.

Serum albumin concentration, arm circumference, and oedema and subsequent risk of dying in children in central Africa.

OBJECTIVE: To measure the prognostic value of clinical, anthropometric, and biological indicators of protein energy malnutrition in hospitalised children. DESIGN: Hospital based follow up study from admission to discharge or death of a cohort of children. SETTING-Paediatric hospital in Zaire. SUBJECTS: 1129 children consecutively admitted between August 1986 and October 1988. MAIN OUTCOME MEASURES: Height, weight, arm circumference, skinfold thicknesses, serum albumin concentration, and mortality. RESULTS: Mortality was higher in wasted children and in those with a mid-upper arm circumference < 125 mm, a serum albumin concentration < 16 g/l, and oedema. After multivariate analysis, serum albumin concentration was the best predictor of subsequent risk of dying. Mid-upper arm circumference and oedema, however, still contributed considerably to evaluation of mortality. CONCLUSIONS: In this specific environment of central Africa an isolated clinical sign such as oedema is not enough to detect children with a high risk of dying among those admitted to paediatric wards with severe protein energy malnutrition. Measurement of additional indicators such as arm circumference and serum albumin concentration seems to be of crucial importance.