PANCREATIC ULTRASONOGRAPHY AS A PREDICTOR OF EXOCRINE ORGAN FUNCTION IN CYSTIC FIBROSIS
DOI:
https://doi.org/10.56238/levv16n53-088Keywords:
Cystic Fibrosis, Pancreatic Insufficiency, UltrasonographyAbstract
Background: Approximately 85% of patients with cystic fibrosis (CF) develop exocrine pancreatic insufficiency (EPI). We aimed to correlate ultrasound (US) echo-intensity of the pancreas with EPI.
Methods: Patients underwent US to measure the echo intensity (histogram) of the pancreatic head in relation to the left lobe of the liver (R ratio). Three cut-off values were defined for R: 1.0, 1.25 and 1.5. Patients were classified into three groups according to these cut-off values and further divided into (a) – with EPI and (b) – without EPI. Data on body mass index, glycaemic status, class I or II genotype, dose of pancreatic enzymes taken per day, presence of EPI (faecal fat ≥ 5 g/day and/or faecal elastase < 200 µg/g) and evidence of pancreatic disease on US (reduced-sized pancreas according to age, “white pancreas” - diffuse increase in echogenicity) were collected. The relationship between variables in the three groups was assessed using the tests of Mann‒Whitney, chi-square and Fisher's exact.
Results: We included 49 patients. There was a significant correlation between white pancreas and R ≥ 1.0 (p = 0.0007), and EPI and R ≥ 1.5 (p = 0.0325). The difference between the R values for patients with or without EPI was statistically significant (p < 0,05).
Conclusions: US is a useful method to predict EPI in CF patients. R values above 1.5 could indicate that the patient is changing the status of pancreatic function and has an indication for other confirmatory tests, such as faecal elastase or quantitative faecal fat test.
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References
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