Novel Radiological Brain Anomalies in a Patient with Congenital Muscular Dystrophy due to FKRP Mexican Founder Mutation c.1387A > G: Review of the Literature

Mutations in the FKRP gene result in phenotypes with severe forms of congenital muscular dystrophies (CMD) and limb-girdle muscular dystrophies. We present a Mexican patient with a pathogenic homozygous mutation in the FKRP gene (c.1387A > G, p.Asn463Asp) and CMD with radiological brain anomalies as disseminated hyperintensity lesions and discrete generalized cortical atrophy. These findings have not been reported to the best of our knowledge in other patients with the same mutation. The mutation c.1387A > G, p.Asn463Asp in the FKRP gene has been described to have a founder effect in central Mexico, since all the patients described to date are of Hispanic origin. Therefore, we emphasize studying mutations in the FKRP gene in Hispanic pediatric patients with clinical suspicion of CMD. Clinical and molecular diagnosis of specific CMD subtypes is needed to help clarify the prognosis, management, and genetic counseling to the patient and families.

MRI Patterns of Non-Enhancing T2-FLAIR Hyperintensity Lesions in Primary CNS Lymphoma

Purpose: The non-enhancing T2-FLAIR hyperintensity lesions at a distance from the enhancing tumor site at baseline have been observed of neoplastic nature in primary central nervous system lymphomas (PCNSL). Our aim was to explore the incidence, location, and morphology of the non-enhancing T2-FLAIR hyperintensity lesions in PCNSL.Methods: We retrospectively reviewed patients diagnosed with immunocompetent PCNSL at our institution. We identified and evaluated the T2-FLAIR hyperintensity lesions without enhancement that markedly decrease or disappear in the MRI after treatment. MRI characteristics of PCNSL at initial presentation were analyzed and compared between patients with non-enhancing T2-FLAIR hyperintensity lesions and patients without these lesions.Results: Among 89 patients, 10 patients (11.2%) were found to have non-enhancing T2-FLAIR hyperintensity lesions at a distance from the enhancing tumor site at baseline, that showed a markedly decrease or disappearance after treatment. The locations of these lesions were as follows: the juxtacortical and deep white matter in 7 lesions, periventricular white matter in 2 lesions, basal ganglia in 1 lesion, and infratentorial aera in 1 lesion. Baseline MRI characteristics in patients with non-enhancing T2-FLAIR hyperintensity lesions exhibited a higher rate of multiple enhancing lesions (P = 0.027), and bilateral enhancing lesions (P = 0.001), compared to patients without non-enhancing T2-FLAIR hyperintensity lesions.Conclusion: Non-enhancing T2-FLAIR hyperintensity lesions at a distance from the enhancing tumor lesions in patients with PCNSL, which indicated of neoplastic nature, was not rare. Those non-enhancing lesions should be incorporated in the initial evaluation of tumor burden and response in the follow up.