Introduction
Lipodystrophy means loss of body fat. It can be either partial or complete. Lipodystrophy can be genetic or acquired. Localized lipodystrophy is an acquired condition that develops later in an individual’s life. Fat loss can occur from single or multiple areas of the body. The complete loss of fatty tissue is called lipoatrophy.
What Are the Subtypes of Localized Lipodystrophy?
Localized lipodystrophy is divided into four subtypes:
-
Pressure-Induced Localized Lipoatrophy: In this subtype, pressure on certain body parts induces fat loss. An example is lipodystrophy semicircularis. It is characterized by horizontal semicircular depressions on the thigh.
-
Panniculitis-Induced Localized Lipodystrophy: There is an eruption of painful nodules that enlarge and resolve into lipodystrophic lesions. The most common areas are the upper and lower limbs.
-
Centrifugal Lipodystrophy: It consists of single or multiple lesions. Lesions can sometimes be painful. They progress from the body’s center to the periphery. It is accompanied by loss of pigmentation, redness, and lymph node swelling. Lesions occur on the groin, abdomen, axilla, head, and neck. It is self-resolving in nature.
-
Idiopathic Localized Lipodystrophy: A focal disappearance of fat happens, mostly from the thighs, abdomen, and ankles. The cause is unknown. The lesions do not resolve spontaneously.
What Are the Causes of Localized Lipodystrophy?
The cause can be inflammatory or non-inflammatory. Some factors that contribute to localized lipodystrophy are:
1. Repeated Injections: Injection use at the same place of the skin in a particular body area is a factor. Subcutaneous and intradermal injections are the most frequent cause. Some examples are:
-
In insulin-dependent diabetes mellitus patients, insulin shots at the same site can lead to this condition.
-
Corticosteroids are used in keloids, alopecia (hair loss), and many other skin conditions. Corticosteroid-induced lipodystrophy occurs after about 1-3 months of injections. The incidence is about 1 to 40 %. Pigmentation loss also occurs in some patients. It leads to huge cosmetic concerns. The exact mechanism is unknown. However, repeated injections may prompt blood vessel constriction, decreased tissue oxygen flow, and collagen synthesis. It ultimately leads to subcutaneous fat dissolution. It might take approximately one to two years to resolve.
2. Autoimmune Diseases: There is an association of localized lipodystrophy with systemic lupus erythematosus (SLE), dermatomyositis, Sjogren’s syndrome, systemic and localized scleroderma, and rheumatoid arthritis (RA). The prevalence is about 40 %. Fat loss occurs on the shoulders, thighs, and chest areas. Lipodystrophy is also linked with human immunodeficiency virus (HIV) syndrome. Loss of fat happens on the face, hips, arms, and legs. It typically leads to deep wrinkling and hollowing of the skin.
3. Trauma: An injury to a specific body site may initiate lipodystrophy. The cause is attributed to the immune mechanism. Trauma may release inflammatory mediators such as cytokines (tumor necrosis factor, interleukin-1). Cytokines possess lipolysis properties due to cross-reactions with lipid tissues and insulin antibodies.
What Are the Clinical Features of Localized Lipodystrophy?
Localized lipodystrophies are rare. As the disease is acquired, it can present at any age. However, females are more affected than males. It usually begins during the first or second decade of life. The presentation includes focal or multiple areas of depression and skin hardening.
1. Lesions: Multiple lesions are well-defined and atrophic. Secondary pigmentation sometimes occurs. The lesion size can increase up to 15 centimeters (cm). Upper arms, hips, and thighs are more commonly affected. The scalp, breasts, and face are spared.
2. Localized Lesions: These occur as muscle and fat changes in focal areas. For example, face involvement in hemifacial atrophy is a manifestation. Hemifacial atrophy is characterized by facial atrophy on one side. Localized scleroderma (morphea) is also connected to lipodystrophy.
How Is Localized Lipodystrophy Diagnosed?
The diagnostic workup of localized lipodystrophy is given below.
1. Laboratory Investigations: Investigations for serum markers of connective tissue diseases can be helpful. In SLE, antinuclear autoantibodies are detected, which are the hallmark of the disease. Rheumatoid factor (RF) and anti-citrullinated protein antibodies (ACPA) characterize RA. Anti-centromere antibodies (ACA) and anti-RNA polymerase III (RNAP III) are raised in scleroderma patients.
2. Biopsy: Biopsy is the investigation of choice in localized lipodystrophy. Microscopic examination is the basis of diagnosis. Two types of microscopic pictures exist.
-
Involutional Fat: It is characterized by small fat cells enclosed in connective tissue, the absence of inflammatory cells, and a large capillary network. This microscopic picture usually shows a single lesion on the upper arm. In addition, serum studies were negative in a study done on three patients with a similar presentation.
-
Inflammatory Type: Fat cells and blood vessel network appear normal. It shows a picture of multiple localized lipoatrophy areas. However, scattered immune cells such as white blood cells, histiocytes, and plasma cells are seen. A biopsy specimen of four patients in a study showed panniculitis (inflammation of the subcutaneous fat). Hence, it exhibits the inflammatory basis of localized lipodystrophy.
How Is Localized Lipodystrophy Treated?
Treatment of localized lipodystrophy includes the following.
1. Medications: Anti-inflammatory drugs such as calcineurin inhibitors (tacrolimus and cyclosporine), steroids, and antimalarials are effective in the initial phase of idiopathic localized lipodystrophy.
2. Cosmetic Treatment: Varied fat distribution in localized lipodystrophy causes patient distress, particularly in females. Autologous fat transfer, dermal fillers, implants, and muscle grafts are beneficial in long-standing conditions.
-
Adipofascial Flap Surgery: Adipofascial flap is a connective tissue flap. It improves the blood supply to the site. Facial contour reconstruction can be performed effectively with the flap. Koshy et al. used it in two patients for the same. The patients perceived a significant improvement in their appearance.
-
Dermal Fillers: Localized lipodystrophy patients can be treated by semi-permanent dermal fillers. It is a safe and effective procedure to improve appearance.
3. Insulin lipodystrophy: This can be prevented by incorporating very thin and short needles in the treatment regimen. Further, rotation of the injection site can help. It is effective in more than 95 percent of patients. Improvement starts in two to four months. However, the skin condition is restored in about two to three months. Switching to purified human or pork insulin has been favorable.
In addition to a negative self-identity, some patients have chronic pain, fatigue, depression, anxiety, and other mood disorders. Therefore, a holistic approach is pertinent in such patients. Treatment of the underlying autoimmune conditions may control the disease progression. Serum markers may be helpful for treatment guidance. Furthermore, a follow-up of the biopsy patients is important to determine disease activity.
Conclusion:
The prognosis of localized lipodystrophy is good. Still, a complete management protocol, including surgery, cosmetic treatment, and psychological support, is necessary to ensure success.
