13C-methionine breath test detects distinct hepatic mitochondrial dysfunction in HIV-infected patients with normal serum lactate.

Objective: To assess mitochondrial respiratory chain dysfunction in different treatment groups of HIV-infected patients with normal serum lactate by measuring hepatic mitochondrial decarboxylation capacity by the C-methionine breath test (MeBT) and to correlate MeBT results with mitochondrial DNA (mtDNA) content in peripheral blood mononuclear cells (PBMCs).

Methods: Four groups were studied: HIV-negative controls (n = 10), treatment-naive patients (n = 15), antiretroviral therapy (ART)-treated patients with asymptomatic disease (n = 15), and patients with long-term treatment and clinical evidence of lipoatrophy (n = 15). After oral administration of C-methionine, CO2 exhalation was determined by infrared spectroscopy.