Epidemiology

Liver symptoms in returning travelers could be due to amoebic liver abscess

Last Updated: 2013-09-09 18:10:19 -0400 (Reuters Health)

By C. Vidya Shankar, MD

NEW YORK (Reuters Health) - Fever and right sided upper abdominal pain following travel to tropical countries could suggest amoebic liver abscess, according to a new study from France.

Delayed presentation was common, especially among those born abroad who later immigrated to France, the researchers reported August 8th online in PLoS Neglected Tropical Diseases.

Nearly a fifth of such individuals became symptomatic more than a year after return from travel to endemic countries, whereas returning native French patients presented earlier.

Due to paucity of data it is difficult to compare the differences, senior author Prof. Olivier Bouchaud from Avicenne Hospital Paris told Reuters Health by email. He attributed the delayed onset of symptoms to IgA-mediated mucosal immunity from prior exposures.

Amebiasis is caused by protozoan Entamoeba histolytica and is spread through the feco-oral route. It is prevalent in the tropics and manifests commonly as colitis or liver abscess. An untreated liver abscess can rupture into adjoining peritoneal, pleural and pericardial cavities and prove fatal, the researchers pointed out.

Their retrospective study involved 90 patients admitted with the diagnostic triad of travel to endemic area, positive Entamoeba serology, and liver abscess identified by imaging. Serology titers above 1:200 for ELISA, 1:100 for immunofluorescence assay (IFA), and 1:320 for immunohemagglutination assay (IHA) were considered positive.

Thirty-eight patients could be confirmed as native French and 37 were known to have been born abroad.

Overall, fever, abdominal pain, diarrhea and nausea were the most common symptoms, occurring in 91%, 81%, 28% and 20% of patients, respectively.

More than three-fourths of patients (77%) presented with a single abscess; the others had multiple abscesses.

Twelve patients developed pleural effusions.

The vast majority (94%) were treated with metronidazole, while the remaining patients received tinidazole or ornidazole. Less than a third (30%) required percutaneous aspiration.

Overall, the median interval to symptom onset after return from travel was 128 days. While all patients who were born in France developed symptoms within a year of return, 17% of those born abroad developed their first symptoms after they'd been back for more than a year.

On multivariate analysis, a large abscess (>69mm) was more likely among immigrants (odds ratio 11.56), males (OR 3.63), and those older than 41 (OR 11.25).

The median time for radiological resolution of abscess was 7.5 months. There were no deaths.

But clinical improvement rather than radiological resolution should be the marker of cure, the researchers emphasized. Persistence of radiological lesions, "should not alarm clinicians during follow-up in patients free of symptoms," they wrote.

As regards prevention, "the best thing to do" is to wash hands before eating, cleaning vegetables and cooking foods, Prof. Bouchaud said.

SOURCE: http://bit.ly/1ali7VE

PLoS Neglected Tropical Dis 2013.