EPI results from progressive failure in the exocrine function of the pancreas to provide its digestive enzymes, often in response to a genetic condition or other disease state, resulting in the inability of the animal involved to properly digest food. Signs and symptoms
Loss of pancreatic enzymes leads to maldigestion and malabsorption, which may in turn lead to:
anemia (Vitamin B12, iron, folate deficiency)
bleeding disorders (Vitamin K malabsorption)
edema (hypoalbuminemia)
fatigue
flatulence and abdominal distention (bacterial fermentation of unabsorbed food)
hypocalcemia
metabolic bone disease (Vitamin D deficiency)
neurologic manifestation
steatorrhea
weight loss

Causes
In humans, the most common causes of EPI are chronic pancreatitis and cystic fibrosis, the former a longstanding inflammation of the pancreas altering the organs normal structure and function that can arise as a result of malnutrition, heredity, or (in the Western world especially), behaviour (alcohol use, smoking), and the latter a recessive hereditary disease most common in Europeans and Ashkenazi Jews where the molecular culprit is an altered, CFTR-encoded chloride channel. According to WebMD, "Crohns disease and celiac disease can also lead to EPI in some people". In children, another common cause is Shwachman-Bodian-Diamond syndrome, a rare autosomal recessive genetic disorder resulting from mutation in the SBDS gene. Diagnosis
The three main tests used in considering a diagnosis of EPI are: fecal elastase test, fecal fat test, and a direct pancreatic function test. The latter is a limitedly used test that assesses exocrine function in the pancreas by inserting a tube into the small intestine to collect pancreatic secretions.
An anal fissure is a break or tear in the skin of the anal canal. Anal fissures may be noticed by bright red anal bleeding on toilet paper and undergarments, or sometimes in the toilet. If acute they are painful after defecation, but with chronic fissures, pain intensity often reduces. Anal fissures usually extend from the anal opening and are usually located posteriorly in the midline, probably because of the relatively unsupported nature and poor perfusion of the anal wall in that location. Fissure depth may be superficial or sometimes down to the underlying sphincter muscle. Untreated fissures develop a hood-like skin tag (sentinel piles) which cover the fissure and cause discomfort and pain. Causes
Most anal fissures are caused by stretching of the anal mucous membrane beyond its capability.Superficial or shallow anal fissures look much like a paper cut, and may be hard to detect upon visual inspection; they will generally self-heal within a couple of weeks. However, some anal fissures become chronic and deep and will not heal. The most common cause of non-healing is spasming of the internal anal sphincter muscle which results in impaired blood supply to the anal mucosa. The result is a non-healing ulcer, which may become infected by fecal bacteria. In adults, fissures may be caused by constipation, the passing of large, hard stools, or by prolonged diarrhea. In older adults, anal fissures may be caused by decreased blood flow to the area.