Concern about prescribing controlled substances
underlies, in part, the undertreatment of pain, even in palliative care
settings. That the same is true for human immunodeficiency virus (HIV) patients
is therefore not surprising, particularly given injection drug use as a risk
Breitbart and DiBiase wisely frame their review of pain and acquired
immunodeficiency syndrome (AIDS) with these issues. They begin with a discussion
of the high prevalence of pain in HIV patients and make the important point that
the problem has not been well studied in women and children. They conclude with
practical suggestions for adapting general pain management guidelines to
individuals with prior or active substance abuse or addiction.
The Role of Accurate Diagnosis
Pain is a symptom of diverse disease processes, including acute or ongoing
visceral or somatic tissue injury, disordered peripheral or central neural
activity, and even depression. Because treatment varies widely by specific
etiology, the importance of understanding what is causing pain, while seemingly
obvious, cannot be overstated.
The prevalence of distal symmetric polyneuropathy (DSP)due to HIV or
caused by the nucleoside antiretrovirals didanosine (ddI, Videx), zalcitabine (ddC,
Hivid), or stavudine (d4t, Zerit) and potentiated by hydroxyureadepends on
how the disorder is defined. The condition is nearly ubiquitous in pathologic
series and was clinically evident in about one-third of a series of AIDS
patients admitted to San Francisco General Hospital. Studies utilizing
electrodiagnostic testing, which is more sensitive than clinical evaluation but
less so than histologic examination, demonstrate a similarly intermediate
prevalence of neuropathy. Hence, not all DSP is painful, and it seems likely
that most is minimally symptomatic.
Conversely, not all pain is DSP. While neuropathic pain and headache were
each evident in about half of ambulatory patients studied by Hewitt et al,
muscle, joint, abdominal, and bone pain each affected over 15% of patients.
Thus, it is not appropriate to simply diagnose any and all limb pain as DSP.
A classic "dying back" axonal neuropathy, DSP shares pathogenesis,
and hence, clinical features, with the most common types of diabetic and
alcoholic polyneuropathy. Symptoms begin symmetrically in the feet, and
examination usually reveals depressed or absent ankle jerks and mild distal
sensory loss, particularly to vibration. The hands are typically not involved
until symptoms, signs, or both ascend to above the midcalf. Weakness is uncommon
unless DSP is quite advanced, and bowel and bladder function are spared.
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peripheral nervous system workshop. Arch Neurol 58:1561-1566, 2001.
3. Hewitt DJ, McDonald M, Portenoy RK, et al: Pain syndromes and etiologies
in ambulatory AIDS patients. Pain 70:117-123, 1997.
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anticonvulsants in HIV-positive individuals. Neurology 54:1404-1407, 2000.
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interaction causes antiretroviral therapy failure. Ann Pharmacother 34:465-470,
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