Final answer:
Unconjugated/indirect bilirubin is formed in the splenic macrophages. It is then transported to the liver to be converted into conjugated/direct bilirubin. The Van Den Bergh tests help distinguish between these two forms.
Step-by-step explanation:
The type of bilirubin formed in the splenic macrophages is unconjugated/indirect bilirubin. When the spleen removes old or damaged red blood cells from the circulation, the breakdown products are transported to the liver. Bilirubin formed during this process is still unconjugated. It then travels to the liver, where it is turned into water-soluble conjugated/direct bilirubin by conjugation with glucuronic acid, a process mediated by the enzyme UDP glucuronyl transferase. This allows it to be excreted in bile and eventually into the intestine, where it is further processed and excreted in feces. The Direct and Indirect Van Den Bergh tests are diagnostic tests used to distinguish between the two types of bilirubin present in the body.