New MRI grading system for the diagnosis and management of mycetoma.

The management of patients with mycetoma depends on accurate identification of the causative organisms and of the extent of disease involvement along the different tissue planes. Disease involvement cannot accurately be assessed with the available diagnostic tools, so in this study we set out to evaluate the effectiveness of MRI in the diagnosis and management of mycetoma. Forty-two patients with confirmed mycetoma had MRI examination of the affected parts. A grading system, The Mycetoma Skin, Muscle, Bone Grading System (MSMBS), was used to describe and grade disease severity on the basis of MRI findings. The logistic regression test was used to correlate the clinical and MRI findings. The study showed that MRI can help in the diagnosis and management of mycetoma patients. The dot-in-circle sign, conglomerated foci with low signal intensity and macro- and micro-abscesses on a background of a hypointense matrix are all diagnostic of mycetoma. In patients with mycetoma, the MSMBS can grade disease severity, compare patients and help to manage them. Further studies are needed to determine to what extent the grading system can be used to determine a patient's prognosis.

A new technique for the diagnosis of mycetoma using fixed blocks of aspirated material.

The aim of this prospective study was to evaluate the use of the cell block technique as a safe, accurate and quick tool for the cytodiagnosis of mycetoma. The study included 240 patients with suspected mycetoma. The suspected lesion was aspirated and the aspirated material was processed to form cell blocks. The cell blocks were processed as described for routine tissue histopathological examination. Haematoxylin/eosin-stained sections were reviewed to identify the morphological features of the mycetoma grains and the different inflammatory tissue reactions. The findings were compared with those seen in histopathological sections. The different mycetoma grains showed distinct morphological features on the cell block that were identical to those seen in histopathological sections. Distinction between eumycetoma and actinomycetoma and their classification according to the causative agent were possible. The cell block technique had sensitivities of 87.5% and 85.7% for eumycetoma and actinomycetoma, respectively, and there were no statistical differences in the findings obtained by the cell block and histopathological techniques. The technique is simple, rapid, specific, sensitive and inexpensive. It can be used in the routine diagnosis of mycetoma and to obtain grains for culture identification. The cell blocks can be preserved for a long period for future studies.