USG guided aspiration of a hepatic cyst shows anchovy sauce appearance of the aspirate. He is most probably infected with:

Entamoeba histolytica causes amebic dysentery and liver abscess. Amebic abscess of the liver is characterized by right-upper-quadrant pain, weight loss, fever, and a tender, enlarged liver. Right-lobe abscesses can penetrate the diaphragm and cause lung disease. Most cases of amebic liver abscess occur in patients who have not had ove intestinal amebiasis. Aspiration of the liver abscess yields brownish-yellow pus with the consistency of anchovy-paste. Ref: (2012). Chapter 51. Intestinal & Urogenital Protozoa. In Levinson W (Eds),Review of Medical Microbiology & Immunology, 12e.