MR imaging of adult acute infectious encephalitis

BACKGROUND

Imaging is a key tool for the diagnosis of acute encephalitis. Brain CT scan must be urgently performed to rule out a brain lesion with mass effect that would contraindicate lumbar puncture. Brain MRI is less accessible than CT scan, but can provide crucial information with patients presenting with acute encephalitis.

METHOD

We performed a literature review on PubMed on April 1, 2015 with the search terms "MRI" and "encephalitis".

RESULTS

We first described the various brain MRI abnormalities associated with each pathogen of acute encephalitis (HSV, VZV, other viral agents targeting immunocompromised patients or travelers; tuberculosis, listeriosis, other less frequent bacterial agents). Then, we identified specific patterns of brain MRI abnomalies that may suggest a particular pathogen. Limbic encephalitis is highly suggestive of HSV; it also occurs less frequently in encephalitis due to HHV6, syphillis, Whipple's disease and HIV primary infection. Rhombencephalitis is suggestive of tuberculosis and listeriosis. Acute ischemic lesions can occur in patients presenting with severe bacterial encephalitis, tuberculosis, VZV encephalitis, syphilis, and fungal infections.

CONCLUSION

Brain MRI plays a crucial role in the diagnosis of acute encephalitis. It detects brain signal changes that reinforce the clinical suspicion of encephalitis, especially when the causative agent is not identified by lumbar puncture; it can suggest a particular pathogen based on the pattern of brain abnormalities and it rules out important differential diagnosis (vascular, tumoral or inflammatory causes).

[Mucosa-associated lymphoid tissue-derived (MALT) lymphoma]

Pulmonary Mucosa-Associated Lymphoid Tissue (MALT)-type lymphoma is the most frequent primary pulmonary lymphoma. We report the case of a patient who presented a pulmonary MALT-type lymphoma treated with chloraminophen, with a recurrence 5 years later characterized with pulmonary lesions associated with a gastric location. This observation underlines some anatomical and clinical aspects of pulmonary MALT-type lymphoma, and leads to discuss the evolution of its physiopathological and therapeutic concepts. In particular, the contributions of positron emission tomography and molecular biology allow the analysis of possible multifocal affections of this disease.

[Script concordance test for knowledge assessment of lung cancer screening]

BACKGROUND

Annual screening for lung cancer using low-dose CT-scans is associated with decreased mortality. A survey conducted in Rhône-Alpes area in France found that clinicians need education and information on this topic. Script concordance tests (SCT) are a tool for assessing clinical reasoning in situations of uncertainty. They have not previously been used in France in the context of continuing medical education.

METHOD

We created a questionnaire with 5 multiple-choice questions (MCQ) and two SCT scenarios. The questionnaire was sent to all clinicians and residents who are members of French-Speaking Respiratory Society or the French Young Pulmonologist Association.

RESULTS

One hundred and ninety answers were analyzed. Seventy percent stated that decreasing mortality was the best criterion for assessing the effectiveness of a cancer screening policy, and 75% that low-dose CT scan was the best test to achieve this in lung cancer screening. Forty-five percent knew the eligibility criteria of the population, and 62% that low-dose CT scan should be performed annually. Participation in tumor boards and certification in oncology were significantly associated with a better score at MCQ and SCT. SCT and MCQ scores were significantly correlated (Spearman's Rho 0.339; P<0.0001).

CONCLUSION

SCT are feasible by electronic survey and seem relevant. Improving knowledge of clinicians on lung cancer screening is still critical.

Clinical presentation of PTEN mutations in childhood in the absence of family history of Cowden syndrome

BACKGROUND

PTEN gene (MIM 601628) is a tumor suppressor gene implicated in PTEN hamartoma tumor syndromes (PHTS) including Cowden syndrome, Bannayan-Riley-Ruvalcaba syndrome, and Proteus-like syndrome. Bannayan-Riley-Ruvalcaba syndrome is considered as the pediatric form of PHTS. More recently, children presenting autism spectrum disorders with macrocephaly (ASD-M) have been reported.

METHODS

We report clinical data from seven patients diagnosed in childhood with a PTEN germline mutation, excluding cases of familial Cowden syndrome.

RESULTS

This study underlines the variability of phenotype associated with PTEN mutations diagnosed at pediatric age. Most of the patients did not fulfill usual criteria of Bannayan-Riley-Ruvalcaba syndrome or ASD-M.

CONCLUSION

PTEN testing should be considered in any child presenting with severe macrocephaly (>+4SD) and another feature of PHTS.