Necrotizing Enterocolitis (NEC): Fecal prolactin is often used as a diagnostic marker for NEC, particularly in premature infants. Elevated levels of prolactin in stool can indicate the presence of NEC, making it a valuable tool in the diagnosis of this condition.

Inflammatory Bowel Disease (IBD): While not as specific as for NEC, elevated fecal prolactin levels can also be seen in conditions like Crohn's disease and ulcerative colitis, which are forms of IBD. The inflammation in the bowel can lead to increased prolactin levels in the stool.
Gastrointestinal Infections: Certain infections of the gastrointestinal tract can cause an increase in fecal prolactin levels. These might include bacterial, viral, or parasitic infections that lead to inflammation and disruption of the normal bowel function.

Intussusception: Although less common, intussusception, a condition where a part of the intestine slides into an adjacent part, can cause bowel obstruction and potentially increase fecal prolactin levels. It's a medical emergency that requires prompt diagnosis and treatment.
Hirschsprung's Disease: This congenital condition affects the large intestine and can cause severe constipation or intestinal obstruction. While not directly linked to fecal prolactin, it's a condition that could potentially lead to changes in bowel habits and requires early diagnosis to prevent complications.

Gastrointestinal Lymphoma: A rare type of cancer that affects the immune cells of the digestive tract. It could potentially cause changes in bowel habits and might be associated with abnormal levels of various markers, including prolactin, in the stool.
Neuroendocrine Tumors: These are rare tumors that arise from the cells of the endocrine and nervous systems. Some of these tumors can produce prolactin, and if they are located in the gastrointestinal tract, they might lead to elevated fecal prolactin levels.