Lipoatrophy lipodystrophy

Lipodystrophy Rarely, administration of insulin subcutaneously can result in lipoatrophy (depression in the skin) or lipohypertrophy (enlargement or thickening of tissue). 

Lipodystrophy, lipoatrophy, or lipohypcrtrophy can be a consequence of chronic local insulin reactions that can be elicited by less pure as well as by highly purified preparations (140), but such reactions can also develop at sites distant to the injection. 

Lipoatrophy, a transient loss of subcutaneous fat identifiable as skin dimpling, occurred in 11% of injections in 75 children who were given modified-release somatropin for 12 months (25) and in one of 68 children in another study (34). Site rotation is recommended to prevent lipodystrophy. 

Dyslipidemia is a common accompaniment of the lipodystrophy syndrome observed in HIV-infected patients. This syndrome presents as a combination of peripheral lipoatrophy and the metabolic syndrome (central adiposity, insulin resistance, and dyslipidemia). The term lipodystrophy syndrome was first used in two case reports to describe a clinical picture of subcutaneous fat wasting in the face and limbs of HIV infected patients treated with indinavir, reminiscent of the rare congenital lipodystrophy syndromes (138,139). In addition, benign symmetric lipomatoses on the trunk and neck were described. A systematic study of this syndrome in the Australian HIV cohort showed co-existence of peripheral lipoatrophy with abdominal visceral obesity, dyslipidemia, and insulin resistance in HIV-infected patients with or without treatment with protease inhibitors (140). 

Other adverse reactions to insulin are lipodystrophy (atrophy or hypertrophy) at the injection sites (rare with purified pork and human insulin), after they have been used repeatedly. These are unsightly, but otherwise harmless. The site should not be used further, for absorption can be erratic, but the patient may be tempted to continue if local anaesthesia has developed, as it sometimes does. Lipoatrophy is probably allergic and lipohypertrophy is due to a local metabolic action of insulin. Local allergy also is marrifested as itching or painful red lumps. 

For therapy of local lumps, extravasation, etc., one should first seek to improve the injection technique. Substitution with highly purified insulin is recommended. Injection with purified insulin into the affected area may speed up resorption of the lumps. Lipodystrophy or lipoatrophy improve after switching to highly purified human or insulin lispro. Lipohypertrophy, on the other hand, often fails to respond to changes in the insulin regimen (130). Varying the injection site may help, but differences in absorption rate then have to be taken into account. 

Insulin, administered subcutaneously, may cause either lipoatrophy or lipohypertrophy. Lipoatrophy is the breakdown of adipose tissue at the insulin injection site causing a depression in the skin at the injection site and occasionally at distant sites also. It may be the result of an immune response or the use of less than pure insulin. Some findings suggest that total lipodystrophy syndrome results from the inflammatory destructive process of adipose tissue (Yanagawa et al., 1990). Injection of human or purified porcine insulin into the site over a 2-4-week period may result in subcutaneous fat accumulation. 

The two forms of lipodystrophy, though less common today in people with diabetes, still occur. Lipohypertrophy is caused by many injections into the same injection site. Due to insulin s anabolic actions, a raised fat mass is present at the injection site with resultant variable insulin absorption. Lipoatrophy, in contrast, is thought to be due to insulin antibodies, with destruction of fat at the site of injection. Injection away from the site with more purified insuhn is recommended, though several reports of lipoatrophy with lispro have been reported. 

D. Other serious toxicities that develop after chronic use of many of these agents include bone marrow depression, diabetes mellitus, hepatotoxicity, lactic acidosis, lipodystrophy, lipoatrophy, pancreatitis, peripheral neuropathy, renal failure, and seizures. 

A number of adipose tissue disorders have been reported. These include conditions of lipodystrophy (where adipose tissue is abnormal but not necessarily absent) and lipoatrophy. Examples of lipodystrophy are lipomas, Dercum s disease and insulin lipodystrophy. Lipoatrophy may be partial or total. 

Metabolism Improvement in lipodystrophy and lipoatrophy upon withdrawal of sfavudine therapy has been reported in 22.9% of 205 children at a mean of 45.6monfhs after discontinuation of sfavudine [168 ]. 

Sawawiboon N, Wittawatmongkol O, Phongsamart W, Prasitsuebsai W, Lapphra K, Chokephaibulkit K. Lipodystrophy and reversal of facial lipoatrophy in perinatally HIV-infected children and adolescents after discontinuation of stavudine. Int J STD AIDS 2012 23(7) 497-501. 

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