Page 170 - AIDSBK23C

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lipid metabolism and insulin action. Pioglitazone has been shown to improve insulin resistance
in persons with HIV infection.[729]
Typical physical findings include central fat accumulation in an abdominal or
dorsocervical distribution (“buffalo hump”), peripheral lipoatrophy with fat atrophy of limbs,
face, and buttocks, and lipomata. Another specific finding seen in a subset of patients with
lipodystrophy is a “pubic lipoma” or pronounced suprapubic fat pad. Pubic lipoma is more
likely to occur in association with coexisting dorsocervical fat pads. This accumulation of
suprapubic fat is more common among women, obese individuals, and those with a shorter
duration of HIV infection.[730]
Metabolic consequences of lipodystrophy include: increased insulin resistance with
increased plasma insulin and decreased oral glucose tolerance, decreased cortisol, increased total
serum cholesterol > 240 mg/dL, HDL cholesterol <35 mg/dL, and increased serum triglyceride
>200 mg/dL. Diabetes mellitus may be seen in 7% of patients with lipoatrophy.[728] In fact,
the serum triglyceride may be over 1000 mg/dL and even approach 9000 mg/dL. Dyslipidemia
is most marked with ritonavir. Up to two thirds of persons taking protease inhibitors may
develop features of lipodystrophy. The rate of development of moderate to severe lipodystrophy
is 20% for those persons on antiretroviral therapy, 8% among those taking less potent
antiretroviral therapy, and 1-2% for antiretroviral-naïve persons. The mean time to appearance
of findings is 10 months after starting protease inhibitor therapy. The prevalence of
lipodystrophy rises for the first two years after initiating antiretroviral therapy but appears to
stabilize thereafter.[731,732]
Treatment for lipodystrophy includes lifestyle modifications with cessation of smoking,
increased exercise, and dietary modifications. Insulin resistance may be treated with metformin.
Surgical management with liposuction has been employed, and appears most efficacious in
decreasing the size of the cervicodorsal fat pad. In addition, gynecomastia may be treated with
subcutaneous mastectomy. Facial wasting may be addressed with facial fillers. Cystic parotid
enlargement can be treated with parotidectomy.[733] Alteration of antiretroviral therapy may be
done. A hydroxymethylglutaryl-coenzyme A (HMG CoA) reductase inhibitor (statin) can be
used for hypercholesterolemia and a fibrate for hypertriglyceridemia.[728] The drug
tesamorelin, an analogue form of human growth hormone-releasing hormone (GHRH) has
shown effectiveness in treatment of lipodystrophy. This analogue resists deactivation in vivo to
increase levels of growth hormone and insulin-like growth factor 1 (IGF1), reducing abdominal
fat and decreasing serum triglyceride and LDL cholesterol.[734]

MISCELLANEOUS FINDINGS.-- Intussusception has been reported to occur in
association with AIDS. This can occur with cytomegalovirus infection or bowel wall
involvement by Kaposi’s sarcoma or non-Hodgkin lymphoma. The diagnosis is suggested by
intermittent cramping abdominal pain in a young to middle-aged adult. Computed tomographic
(CT) scans aid in confirmation of this diagnosis. The many opportunistic infections and
neoplasms affecting the gastrointestinal tract in patients with AIDS can predispose to
intussusception.[416,735] Intussusception in pediatric AIDS is associated with Kaposi sarcoma
in the absence of cutaneous lesions.[736]
The toxic side effects of antiretroviral therapy with either antiretroviral drugs or protease
inhibitors may lead to nausea, vomiting, and diarrhea. Such adverse reactions are most likely to
occur with zidovudine, didanosine, nelfinavir and saquinavir.[255,261,264] These symptoms
may be severe enough to limit use of the drugs.