Finger printing of mycobacterium tuberculosis in patients with intracranial tuberculomas by using in vivo, ex vivo, and in vitro magnetic resonance spectroscopy

Abstract

In vivo, ex vivo, and in vitro proton magnetic resonance spectroscopy was performed in 12 patients with intracranial tuberculomas with an aim of detecting the biochemical constituents of Mycobacterium tuberculosis in a granuloma. One dimensional (1D) single pulse and spin-echo sequences and 2D correlative spectroscopy were used for the ex vivo study to confirm the resonances seen on in vivo study. Spectroscopic studies of the perchloric acid and lipid extract of granuloma and M. tuberculosis were performed to look for similarity of resonance. In vivo study showed the presence of lipids at 0.9, 1.3, 2.0, 2.8 ppm, and phosphoserine at 3.7 ppm. All these resonances were confirmed on ex vivo study. In addition, distinct resonances of serine and phenolic lipids were seen on ex vivo and in vitro study of tuberculous granuloma, which have not been observed in other intracranial tumors. Lipid extract of granuloma and M. tuberculosis showed phenolic lipids at 7.1 and 7.4 ppm, a constituent of the cell wall of the bacteria in a tuberculoma. It appears that it may be possible to finger print the biochemicals of the cell wall of M. tuberculosis in a tuberculous granuloma and thus may help in detection and diagnosis of such lesions.

Spectroscopic increase in choline signal is a nonspecific marker for differentiation of infective/inflammatory from neoplastic lesions of the brain

“…With maturity, the lesions demonstrate hypointense areas and pathologically have solid caseation surrounded by cellular reaction. MR spectroscopy of tuberculomas has shown only lipid resonances and no choline peak (3,22,23). These spectra represent only the T2 hypointense solid caseation found in the center of mature tuberculomas, and the volume of interest in these reports is confined to this central caseating area.…”

Inflammatory granulomas: evaluation with proton MRS

“…One would, therefore, prefer a noninvasive investigative tool that would facilitate the diagnosis of these lesions. At a time when the clinical potential of proton magnetic resonance spectroscopy (MRS) is being evaluated for several neuropathologies with encouraging results, there are very few reports of MRS in intracranial inflammatory granulomas (IG), [4][5][6] and no reports on comparative MRS studies on the different types of IGs discussed above. The aim of the present study is to examine the possible role of proton MRS in differentiating between tuberculomas, NCC and non-specific IG.…”

Spectrum of Intracranial Tuberculosis on Magnetic Resonance Imaging

“…Gupta RK, Pande R, Khan EM, et al 14 stated that the MRS of the tuberculoma demonstrates lipid peaks at 0.9, 1.3, 2.0 and 2.8ppm and phosphoserine peak at 3.7ppm.…”