Validation of fecal elastase-1 determination using immunoenzymatic assay in HIV-infected patients

Fecal elastase-1 in healthy children up to 2 years of age: a cross-sectional study

BACKGROUND

Fecal elastase-1 (E-1) levels in infants and young children may be expected to differ from those in adults and older children because of the immaturity of the gastrointestinal tract and the specificity of their diet. Despite the availability of data describing E-1 levels in the stools of preterm infants, older children, adults and subjects with malabsorption, there is still a lack of data regarding E-1 in healthy infants and toddlers. The aim of this cross-sectional study was to evaluate fecal E-1 concentrations in infants and children from 1 up to 24 months of age.

MATERIAL AND METHODS

E-1 was measured in 160 healthy subjects aged 1-24 months (8 groups of 20: aged 1-3, 4-6 months, etc.) using an enzyme-linked immunosorbent assay (ELISA).

RESULTS

Fecal E-1 concentrations ranged from 200 to 1695 μg/g of feces. No child had a fecal E-1 level below 200 μg/g of feces. Fecal E-1 concentrations did not significantly differ between age groups. However, fecal E-1 levels in the first 3 months were lower than in the second year of life (1-3 months vs 13-24 months, p=0.0230). A statistically significant correlation between the E-1 concentration and age was found (p=0.0007, r=0.2639; however, it does not affect the cut-off level of the reference values). The trend was rather exponential. Fecal E-1 values reached a plateau around the age of 6-10 months.

CONCLUSIONS

Our study has shown that the fecal E-1 test can be reliably applied in infants and toddlers to confirm normal exocrine pancreatic function. However, within the first months of life fecal E-1 concentrations may be lower than later in life.

Novel Testing Enhances Irritable Bowel Syndrome Medical Management: The IMMINENT Study

Primary Study Objective:

To evaluate the economic utility of a fecal biomarker panel structured to suggest alternative, treatable diagnoses in patients with symptoms of irritable bowel syndrome (IBS) by quantifying, comparing, and contrasting health service costs between tested and non-tested patients.

Study Design:

Retrospective, matched cohort study comparing direct medical costs for IBS patients undergoing fecal biomarker testing with those of matched control subjects.

Methods:

We examined de-identified medical and pharmacy claims of a large American pharmacy benefit manager to identify plan members who underwent panel testing, were eligible for covered benefits for at least 180 days prior to the test date, and had data available for 30, 90, and 365 days after that date. We used propensity score matching to develop population-based control cohorts for each tested cohort, comprised of records with IBS-related diagnoses but for which panel testing was not performed. Primary outcome measures were diagnostic and medical services costs as determined from claims data.

Results:

Two hundred nine records from tested subjects met inclusion criteria. The only significant baseline differences between groups were laboratory costs, which were significantly higher in each tested cohort. At each follow-up time point, total medical and gastrointestinal procedural costs were significantly higher in non-tested cohorts. Within tested cohorts, costs declined significantly from baseline, while costs rose significantly in non-tested control cohorts; these differences were also significant between groups at each time point.

Conclusions:

Structured fecal biomarker panel testing was associated with significantly lower medical and gastrointestinal procedural costs in this study of patients with IBS symptoms.

Pancreatic insufficiency in HIV: is it possible?

Pancreatic involvement in AIDS is very important and common, but there are few studies in the literature concerning the pancreas in AIDS. Therefore, our research involves an important issue in the pancreatic field. The objective of the study was to evaluate the profile of HIV-infected patients with probable exocrine pancreatic insufficiency and its relation to the degree of human immunodeficiency virus (HIV) infection. This is a cross-sectional study carried out at Faculdade de Medicina do ABC in partnership with the basic health care unit Vila Guiomar in Santo André. We selected 118 individuals divided into four groups (a control group and three other groups composed of AIDS patients, separated according to CD4 levels); participants had an interview, completed a questionnaire, and had laboratory and imaging tests. The only clinical variables with significant differences among the studied groups were the use of highly active antiretroviral therapy (HAART), the incidence of opportunistic infections, the administration of chemoprophylaxis, and weight loss. There were no differences in the amylase, lipase, and steatocrit dosages among the groups. Levels of fecal elastase 1 were lower in the HIV patient groups (2, 3, and 4) when compared with the control group, although all of them showed average levels that were much higher than the cutoff point (200 μg/g). Only nonalcoholic individuals showed a relationship between diarrhea and alterations in elastase levels. A relationship between the use of HAART and exocrine pancreatic insufficiency in different phases of HIV infection could not be verified.

Pancreatic insufficiency in patients with HIV infection: role of didanosine questioned

OBJECTIVES

The aim of the study was to identify possible causes of pancreatic insufficiency in patients with HIV infection.

METHODS

A retrospective analysis of 233 HIV-positive patients for whom faecal elastase measurement was available was performed to investigate potential associations with core demographic data, HIV infection characteristics, degree of immunosuppresion, exposure to antiretroviral therapy (ART), alcohol misuse, diabetes, hepatitis C virus (HCV) infection, triglyceride and cholesterol levels and symptomatology. The response to pancreatic enzyme replacement for patients with evidence of insufficiency was also evaluated.

RESULTS

Of 233 patients, 104 (45%) had evidence of pancreatic exocrine insufficiency (faecal elastase < 200 mcg/g). A positive association with exocrine pancreatic insufficiency was found for HCV infection (P = 0.007), previous or current HCV treatment (P = 0.003), alcohol misuse history (P = 0.006) and the presence of steatorrhoea (P = 0.03). There was no demonstrated association between exocrine pancreatic insufficiency and didanosine (ddI) exposure (P = 0.43) or stavudine (d4T) exposure (P = 0.62). Seventy-seven per cent of patients who were treated with pancreatic enzymatic supplementation reported a subjective improvement in symptoms.

CONCLUSIONS

Faecal elastase sampling should form part of the routine work-up for HIV-positive patients with chronic diarrhoea even in the absence of 'traditional' risk factors such as ddI exposure. In particular, if the patient has steatorrhoea, a history of alcohol exposure or their HCV serology is positive, they should be considered for investigation. Treatment with pancreatic enzyme supplementation appears to be effective in the treatment of chronic diarrhoea caused by pancreatic insufficiency in the majority of patients.