Urine methyl malonic acid levels in HIV-infected adults with peripheral neuropathy

Background: Cobalamin deficiency and peripheral neuropathy (PN) are commonly seen in HIV-infected adults. The level of urine methylmalonic acid (UMMA), a reliable indicator of tissue cobalamin status, was determined in HIV infected subjects with and without PN to establish this association. Methods: One hundred and ninety-eight (198) consenting HIV infected subjects with and without PN were recruited for the study. UMMA level was determined by Cation Exchange High Performance Liquid Chromatography (HPLC) with Ultraviolet detector in 165 subjects. Simple proportions of patients with raised UMMA (defined as value> 3.4 mg in 24hr) were determined for each arm.Results: Among the 198 subjects studied, 146 had PN and 52 had no PN. From the 165 subjects whose UMMA was studied, raised UMMA was found in 76.6% (36 of 47) of subjects with no PN as compared with 53.4% (63 of 118) of those with PN (p=0.018).Conclusion: Cobalamin deficiency (measured by UMMA level) even though common in HIV infected subjects, may not be the cause of peripheral neuropathy in these subjects.