Fat Necrosis - An Overview

Introduction:

Fat necrosis results from toxin invasion in the body leading to tissue dysfunction. Necrosis leads to protein denaturation, cellular swelling, and, eventually, organular breakdown. Microscopically, it appears yellowish white to cloudy white in appearance. Most of the time, this necrotized tissue is digested by enzymatic reaction and phagocytic action. This further prevents mineral calcification in tissues.

What Causes Necrosis of Fat Tissue?

Necrosis of tissue is caused due to pancreatic injury, also known as acute pancreatitis. This is an emergency condition arising in the stomach. The pathogens are released from the pancreatic enzymes into adjacent cells and the peritoneal cavity. These released pancreatic enzymes react with triglyceride esters present inside them. As a result, these fat cells are converted into liquefied mass. The accumulated necrotized tissue, if not eliminated from the body, attracts the calcium salts causing calcification.

What Are the Different Kinds of Fat Necrosis?

Fat necrosis is of two types:

• Pancreatic Necrosis: Any inflammation of the pancreas is known as pancreatitis. This could be both acute and chronic. The rise in pancreatic enzymes gives rise to necrosis of the pancreas. The release of lipase causes fat necrosis. Damage to the blood supply due to necrosis is known as acute hemorrhagic pancreatitis.

• Traumatic Fat Necrosis: This is caused by trauma to the breasts. It is a rare condition with an innocuous lesion. The growth of mass tissue characterizes it.

What Causes Fat Necrosis in the Pancreas?

There are many factors triggering this condition. Among these, the most common ones are gallstones and alcoholism. The common cause of this necrosis is the phagocytic action of pancreatic substances and an imbalance in the production of pancreatic enzymes.

What Are the Metabolic Factors Seen in Fat Necrosis of the Pancreas?

1. Alcohol - Direct consumption of alcohol does not cause necrosis but can lead to it. This is seen in patients who have been regular users of alcohol for more than five years. Alcohol can sensitize the pancreas to external and internal factors causing damage, like smoking and fat intake. The formation of calcium salts results from the enzymes' pancreatic precipitate. This forms a protein plug in the small intestine, which again forms calculi and leads to inflammation.

• Symptoms- Vomiting, pain, anorexia (a condition when people lose their appetite as a result of emotional states like anxiety, annoyance, rage, and fear), nausea, and pancreatic diabetes.

• Treatment- Analgesics and anti-emetics, intravenous fluid therapy, and electrolyte replacement.

1. Hyperlipoproteinemia - The increased circulation of fat in the bloodstream. A diet containing larger amounts of saturated fat is one of the causes, like eggs, meat, butter, and milk. It could be due to familial factors also. This can lead to a condition called atherosclerosis. A condition in which blood vessels are blocked with cholesterol crystals. It can lead to other severe conditions like ulceration, thrombosis, hemorrhage, and aneurysm.

• Symptoms- Ischemic bowel disease, gangrene, thromboembolism, myocardial infarction, and brain damage.

• Treatment- Statin and cholesterol medicines, exercise, and a healthy diet.

1. Hypercalcemia- It is a condition where calcium levels are elevated. It is mainly caused by dysfunction of parathyroid glands. High calcium levels can lead to depletion of kidney function (kidney stone) and other activity of the brain.

• Symptoms- Increased thirst and increased urination, muscle and bone pain, fatigue, and stomach ache.

• Treatment- Removal of parathyroid gland and medications.

1. Drugs- Certain medications for diabetes, neuropsychotropics, antipsychotics, antidepressants, and anticonvulsant drugs have been associated with fat deposition in the body.

1. Genetic- Hereditary genetic dysfunction of lipoprotein metabolism is a major risk factor for familial hypercholesterolemia.

What Are the Mechanical Factors Involved in Fat Necrosis of the Pancreas?

Gallstones-Gallstones or cholelithiasis is a condition where fat deposition leads to crystal or stone accumulation in the gallbladder.

• Symptoms- Inflammation, liver cirrhosis, jaundice (yellowing of the skin or whites of the eyes produced by an excess of the pigment bilirubin and often caused by bile duct obstruction, liver illness, or excessive red blood cell breakdown), obesity, malabsorption, and diabetes.

• Treatment- Surgical removal of gallstones or gallbladder.

Other factors like trauma and perioperative injury can also induce fat deposition.

What Are the Vascular Factors Responsible for Fat Necrosis?

• Shock - It is the decrease in blood flow leading to hypotension and hypoperfusion. Reduced blood flow and inadequate perfusion of cells can lead to fat deposition and multiple organ dysfunction syndrome (MODS), along with other associated conditions. It can lead to conditions like hemorrhage, burns, dehydration, and outflow obstruction.

• Atheroembolism - It is a condition in which fat crystals are ruptured from blood vessels to nearby small renal arteries. Administration of statin and other cholesterol drugs is the prophylactic measure.

• Polyarteritis Nodosa (PAN)- It is an inflammation of blood vessels. This is caused due to necrosed lesions.

• Symptoms- Fever, fatigue, loss of appetite, and weight loss.

• Treatment- Medications like Prednisone and Cyclophosphamide.

How Can One Diagnose Fat Necrosis?

Radiography is usually able to diagnose fat necrosis, yet there are two potential problems. The appearance of fat necrosis frequently occurs much later than the injury that initially caused it. Approximately one and a half years following injury is when fat necrosis first starts to show symptoms. Fat necrosis may go unnoticed by one and their healthcare provider if a person is unable to recall the damage or if they were unaware that the tissue was being affected at the time.

This is when a thorough medical history becomes important. The doctor will inquire about any past illnesses, surgeries, injuries, and treatments one may have received in the past few years.

Another challenge lies in the fact that, when examined physically and through imaging testing, fat necrosis might mimic cancer. While a prior diagnosis of cancer is a powerful predictor of fat necrosis, it also carries the risk of cancer reoccurring. An individual and their healthcare practitioner want to be certain of which. This may occasionally necessitate removing a sample of tissue for analysis.

What Tests Are Performed to Diagnose Fat Necrosis?

To detect fat necrosis, a physician could recommend a variety of imaging studies, such as

• X-rays.

• Ultrasound.

• CT scan (Computed tomography- scan).

• MRI (magnetic resonance imaging).

• The healthcare practitioner may do a needle biopsy if they need to verify the fat necrosis in the lab.

What Are the Infectious Factors Leading to Fat Necrosis?

Certain infectious agents like Mumps virus, Coxsackievirus, and Mycoplasma pneumoniae are causative agents for fat necrosis. In conditions like epi pericardial fat necrosis, inflammatory changes, and necrotized lesions are observed. This leads to ischemia and increased capillary pressure. Administration of non-steroidal anti-inflammatory medications can be done.

What Is Fat Necrosis of Breast?

It is a palpable fat or oil deposition seen in breasts. It is painless or sometimes tenders on palpitation. This is formed due to damage to fat cells in breasts leading to the secretion of oil from small sacs. It can also develop due to radiation, breast surgery, or trauma caused by fat cells. Women around perimenopausal age are found to be the victims of breast necrosis. Management of breast necrosis can be done using a hot compress and intake of anti-inflammatory drugs. Diagnostic tests like biopsy can be performed to rule out the condition of breast cancer.

Conclusion:

Fat necrosis is a benign condition and is curable. It rarely causes pain and is self-healed on its own. The most common fat necrosis is seen among women - necrosis of the breast. Hence, nursing or lactating mothers are advised to take care of any injury induced during nursing, such as dermatitis of a nipple and inspissation of secretion through fissures in the nipples.