689 Recognition of HIV-associated Sensory Neuropathies; Evaluation of a Clinical Screening Tool C. Cherry*1,2, J. McArthur3, S. Wesselingh1,2,4 1Monash Univ, Melbourne, Australia; 2Alfred Hosp, Melbourne, Australia; 3Johns Hopkins Univ, Baltimore, MD; and 4Burnet Inst, Melbourne, Australia
Background: Sensory neuropathies (SN) are the commonest neurological complications of HIV infection, and the prevalences of both distal sensory polyneuropathy (DSP) and antiretroviral toxic neuropathy (ATN) have risen since the introduction of HAART. A simple, reproducible tool for diagnosing SN is needed both to monitor patients (pts) on potentially neurotoxic medications, and to identify pts with pre-existing SN when considering commencing or changing antiretroviral therapy.
Methods: We applied a standardized clinical screening tool for SN to 80 ambulatory individuals with HIV infection. Subjects were classified on this basis as neuropathy-free (no symptoms or signs, n = 31), possible SN (symptoms but no signs, n = 13), or SN (symptoms and signs, n = 36). We did not distinguish between DSP and ATN for this analysis. Quantitative sensory threshold testing (QST) was performed on all subjects and 30 HIV uninfected controls using a computerized sensory testing device (CASE IV).
Results: Subjects with SN performed less well on all QST modalities than those without SN (p < 0.0001 for vibration, cooling, and warming). Warming thresholds (reflecting small fiber dysfunction) were elevated in HIV+ subjects, both with and without SN compared with controls (p < 0.0001 between all groups). However, subjects with possible SN did not perform differently on QST than those with no SN (p > 0.14 for all modalities), demonstrating the poor specificity of symptoms alone in the diagnosis of SN. Among the symptoms, numbness was most strongly associated with abnormal QST performance (p < 0.0001 for all modalities). In addition, both clinical signs assessed (reduced ankle jerks and reduced vibration sense in the great toe) were strongly associated with poor QST performance (p < 0.0001 for all modalities for each).
Conclusions: These results confirm that HIV+ individuals may have impaired sensory function even in the absence of SN, but that a standardized clinical screening tool accurately detects those with more severe sensory dysfunction. This tool is rapid and inexpensive to administer and provides a simple, non-invasive method of screening HIV+ pts for the presence of sensory neuropathy.
