Lipodystrophy
Lipodystrophy is a pathologic loss or abnormal redistribution of adipose tissue, most often encountered as antiretroviral-associated fat redistribution in HIV infection (central visceral fat gain from protease inhibitors, peripheral lipoatrophy from older thymidine-analogue nucleoside reverse transcriptase inhibitors) or as focal lipohypertrophy/lipoatrophy at chronic insulin injection sites. Management centers on removing or switching the causative drug, treating the resulting insulin resistance and dyslipidemia with standard agents, and, for HIV-associated visceral fat accumulation, tesamorelin 1.28 mg subcutaneously once daily.
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What this article covers
- Overview
A pathologic loss or abnormal redistribution of adipose tissue, not a single disease: lipodystrophy describes fat that is lost (lipoatrophy) or abnormally redistributed into specific depots…
- Epidemiology
Recognized wherever protease inhibitor- or thymidine-analogue-based antiretroviral regimens are used: the syndrome emerged as a recognized complication with the introduction of protease inhibitors and older NRTIs in antiretroviral therapy.
- Risk factors
Protease inhibitor-based antiretroviral therapy: atazanavir, darunavir, indinavir, lopinavir, and saquinavir are associated with the central fat-redistribution pattern.
- Pathophysiology
Protease inhibitors alter lipid and glucose handling through insulin resistance: these drugs induce insulin resistance, producing hyperglycemia and hyperlipidemia alongside redistribution of fat to…
- Clinical features
Central or truncal fat accumulation: in the protease-inhibitor pattern, fat redistributes to the abdomen and back.
- Differential diagnosis
Cushing syndrome: central fat redistribution with dorsocervical and facial fat deposition, but distinguished by accompanying thin skin, purple striae, and proximal muscle weakness, and confirmed by…
- Diagnosis
The diagnosis is confirmed clinically by a compatible fat-distribution pattern in a patient with the relevant drug exposure, most often antiretroviral therapy containing a protease inhibitor, a…
- Management
First, identify the specific causative antiretroviral drug (stavudine, zidovudine, atazanavir, darunavir, indinavir, lopinavir, or saquinavir) and consult the treating HIV specialist about switching…
- Complications
Insulin resistance progressing to overt diabetes: sustained hyperglycemia from protease-inhibitor-associated insulin resistance can progress to a diagnosis of diabetes if unaddressed.
- Prognosis
Partially reversible with early recognition and agent switching: peripheral lipoatrophy and central fat accumulation can improve, though not always fully resolve, after switching away from the causative antiretroviral agent.
- Prevention
Rotate insulin injection sites systematically to prevent localized lipohypertrophy or lipoatrophy from repeated injection into the same location.
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