Contributo della risonanza magnetica spettroscopica del protone (1H-RMS) nella infezione da HIV

Abstract

English

È stato condotto uno studio combinato di RMI e 1H-RMS (Magnetom Siemens 1,5 Tesla) in 60 pazienti sieropositivi per HIV (n. 25 encefalopatie-HIV correlate, n. 20 toxoplasmosi, n. 8 PML, n. 7 linfomi) e 22 controlli neurologici sieronegativi per HIV. Gli spettri sono stati acquisiti su volumi singoli localizzati su lesioni focali in toxoplasmosi, PML, linfomi o su lesioni diffuse nelle encefalopatie da HIV (sequenza Spin Echo, TE 135 ms).

In tutti i sottogruppi HIV si è evidenziato un significativo decremento del rapporto NAA/Cr rispetto ai controlli neurologici, suggerendo un danno neuronale e/o assonale indipendentemente dall'eziologia. Tuttavia il rapporto NAA/Cr era più basso nelle PML e nei linfomi.

Un significativo incremento del rapporto Cho/Cr era rilevato nelle encefalopatie da HIV, nelle PML e in particolare nei linfomi ove tale incremento era associato alla presenza del segnale dei lipidi, marker entrambi di un aumentato turnover e sintesi di membrane cellulari. Nelle PML si rilevava infine con elevata frequenza il segnale del lattato. I dati confermano una elevata sensibilità della 1H-RMS nel rilevare una compromissione metabolica cerebrale in corso di infezione da HIV. Nonostante una globale scarsa specificità nel discriminare lesioni di differente eziologia, determinati pattern metabolici possono risultare di supporto alla RMI per la diagnosi eziologica di alcune lesioni, per esempio di PML.

Keywords

magnetic resonance spectroscopy magnetic resonance imaging HIV infection These data suggest that 1H-MRS may be considered a sensitive means to evaluate brain metabolic involvement during HIV infection. Although the overall specificity appears to be poor in defining the aetiology of different brain lesions homogeneous biochemical patterns could support MRI in the differential diagnosis of some lesions such as PML

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