Lipoprotein (a) and acute-phase response in patients with vestibular neuronitis

Vestibular neuronitis (VN) is a relatively common condition characterized by the acute onset of vertigo, nausea and vomiting, in the absence of auditory or central nervous system involvement. The exact aetiology (inflammatory, viral or vascular?) remains obscure. Lipoprotein (a) [Lp(a)] is an atherogenic particle. Its serum levels are mainly genetically determined and vary widely between individuals. Whether Lp(a) is consistently a positive acute-phase reactant is controversial.

We evaluated the alterations in lipidaemic parameters and serum biological markers (including acute-phase reactants) in adult patients presenting acutely with VN.

A total of 34 consecutive VN patients (24 men and 11 women) and 37 apparently healthy controls (25 men and 12 women) were studied. Laboratory evaluation was performed during the acute episode and 6 months later (stable state).

Serum Lp(a) concentrations were significantly lower at the time of presentation (median value 6.4 vs. 16.4 mg dL-1 in the stable state, P < 0.001), whereas fibrinogen levels were significantly higher during the acute episode than in the stable state (median value 293.0 vs. 202.0 mg dL-1, respectively, P < 0.0001). During the acute episode, plasma fibrinogen correlated with CRP levels (Spearman r = 0.84, P < 0.0001). By contrast, inverse correlations were noted between Lp(a) levels and CRP (Spearman r = -0.47, P = 0.007) as well as between Lp(a) and fibrinogen levels (Spearman r = -0.35, P = 0.05).

Vestibular neuronitis episodes are associated with evidence of an acute inflammatory response as reflected by significant elevations in plasma fibrinogen and CRP concentrations, whereas Lp(a) behaves as a negative acute-phase reactant.