Acquired Partial Lipodystrophy - Causes, Diagnosis and Treatments

Introduction:

Otherwise known as Barraquer-Simons syndrome or cephalothoracic lipodystrophy, acquired partial lipodystrophy (APL), as its name suggests, is an acquired condition, meaning that it develops at some point in life and it is not by birth. In this condition, there is a problem with the way the body stores and uses the fat. Barraquer, Simons, and Mitchell described this condition a century ago and named it lipodystrophia progressiva or Barraquer-Simons syndrome, which was later known as acquired partial lipodystrophy.

What Is Acquired Partial Lipodystrophy?

Lipodystrophy is the loss of adipose (fat) tissue. When this loss of subcutaneous fat tissue is not uniform in the body and is restricted to only certain regions, it is termed acquired partial lipodystrophy. Fat loss in APL is not intentional, meaning people do not practice specialized diets or workouts to lose fat; instead, it occurs on its own without any reason or effort. Also, in such people, ectopic fat in the liver and muscle tissues increases.

This lipodystrophy is symmetrical and bilateral, limited to the upper body with cephalometric progression and sparing the lower extremities. Some also use the term lipoatrophy instead of lipodystrophy interchangeably.

What Causes Acquired Partial Lipodystrophy?

How acquired partial lipodystrophy develops or what are the causes is not clearly understood but,

• It is said that more commonly, APL develops following an acute viral infection such as measles.

• An autoimmune disease can also trigger APL (where there is autoimmune-mediated destruction of adipocytes or fat cells).

• In the affected people, the alternative complement pathway gets activated, and the same signs are present.

• Low levels of circulating complement C3 (a factor responsible for immune response). This condition is also known as hypocomplementemia.

• Presence of the C3-nephritic factor (an autoantibody that targets and damages the healthy tissues by mistake).

What Are the Clinical Features of Acquired Partial Lipodystrophy?

• APL usually develops in childhood or adolescence. But its incidence in the fourth and fifth decades of life is also reported.

• It is a slowly progressing condition, and fat distribution is uniform all over the body during birth and early childhood. Eventually, there is an absence of fat under the skin in some areas of the body. This gradual fat loss more commonly develops within an 18-months course. It occurs on and off over the years.

• By the age of 13, the loss of subcutaneous fat from the face becomes evident.

• Their physique looks disproportionate due to the loss of fat in the upper half of the body.

• People with APL are susceptible to bacterial infections due to poor immune responses.

What Parts of the Body Does Acquired Partial Lipodystrophy Affect?

Loss of subcutaneous adipose tissue occurs in the following bodily sites:

• Face.

• Arms.

• Forearms.

• Neck.

• Chest.

• Shoulders.

• Upper abdomen.

Since the lower parts of the body are usually spared, after puberty in some women, there is excessive fat accumulation in the hips, thighs, and leg region.

What Other Conditions Co-Exist With Acquired Partial Lipodystrophy?

• Nearly after more than 10 years of APL onset, around 1 in 5 people develop membranoproliferative glomerulonephritis.

• Due to deficient adipose tissues and leptin (a hormone made by fat cells and helps regulate energy balance) deficiency, insulin resistance occurs. Insulin resistance can increase cardiovascular risk.

• Diabetes mellitus.

• Dyslipidemia.

• Hypertension.

• Hepatic steatosis.

• Some people develop drusen (accumulation of small yellow or white hyaline bodies in the retina).

• Macular degeneration.

• Deafness.

• Epilepsy.

• Mental retardation.

• Hepatomegaly.

What Autoimmune Disorders Are Associated With Acquired Partial Lipodystrophy?

APL can also be associated with autoimmune disorders like,

• Systemic lupus erythematosus (SLE).

• Dermatomyositis.

• Hypothyroidism.

• Pernicious anemia.

• Celiac disease.

• Dermatitis herpetiformis.

• Rheumatoid arthritis.

• Temporal arteritis.

• Leukocytoclastic vasculitis.

In these conditions, APL usually follows these autoimmune conditions.

How Common Is Acquired Partial Lipodystrophy?

APL is a rare disorder. Only about 250 cases have been described until now, out of which a majority of them are of European descent. It has a female predilection, meaning females are affected three to four times more frequently than males.

How Is the Diagnosis of Acquired Partial Lipodystrophy Made?

• Diagnosis of APL is usually through identification of the presenting symptoms of fat loss in selective areas, detailed patient history, clinical evaluation, and investigative tests.

• A blood chemical profile will be ordered to assess the levels of glucose, lipids, liver enzymes, and uric acid.

• Decreased serum C3 levels, normal C1 and C4 levels, and high levels of the autoantibody C3NeF (nephritic factor) are diagnostic of APL.

• C1, C3, and C4 are complement factors that play an important role in the immune response.

• An MRI (magnetic resonance imaging) of the whole body can reveal the characteristic fat loss pattern.

• If APL is suspected, a renal biopsy will also be suggested to make a confirmed diagnosis.

How Can Acquired Partial Lipodystrophy Be Treated?

• There are no approved drugs to cure APL as of now. The treatment of APL is symptom-oriented. It cannot be cured, but the symptoms can be improved with treatment.

• The combined efforts of various specialists such as pediatricians, endocrinologists, cardiologists, plastic surgeons, nutritionists, and other healthcare professionals would be required for the effective management of this condition in affected children.

• Genetic and psychological counseling is of utmost importance to support the family soon after the diagnosis as it would cause immense stress and anxiety to the family.

• Healthy weight needs to be maintained.

• Regular exercise is necessary.

• Affected individuals are encouraged to follow a lipid-lowering diet.

• In adults with APL, cosmetic surgery is advised to improve their physical appearance.

• Liposuction in selective areas of fat deposition can also be beneficial.

• If a liver failure occurs, liver transplantation is done.

• In the case of end-stage kidney disease, kidney transplantation is performed.

Conclusion:

Acquired partial lipodystrophy can be mentally devastating to the child. As the child reaches adulthood, the disproportionate fat loss and accumulation become evident, which results in psychological discomfort and affects the quality of life. Affected individuals and their families are encouraged to seek psychological support. Regular follow-ups with concerned specialists will help prevent life-threatening complications.