How brain tumors progress from precancerous lesions to advanced cancers is not well understood. Using Ptch1(+/-) mice to study medulloblastoma progression, we found that Ptch1 loss of heterozygosity (LOH) is an early event that is associated with high levels of cell senescence in preneoplasia. In contrast, advanced tumors have evaded senescence. Remarkably, we discovered that the majority of advanced medulloblastomas display either spontaneous, somatic p53 mutations or Cdkn2a locus inactivation. Consistent with senescence evasion, these p53 mutations are always subsequent to Ptch1 LOH. Introduction of a p53 mutation prevents senescence, accelerates tumor formation, and increases medulloblastoma incidence. Altogether, our results show that evasion of senescence associated with Ptch1 LOH allows progression to advanced tumors.

Pneumoperitoneum is not always associated with hollow viscus perforation. Such condition is called non-surgical or spontaneous pneumoperitoneum. Intrathoracic causes remain the most frequently reported mechanism inducing this potentially life threatening complication. This clinical condition is associated with therapeutic dilemma. We report a case of a massive isolated pneumoperitoneum causing acute abdominal hypertension syndrome, in a 75 year female, which occurred after difficult airway management and mechanical ventilation. Emergent laparotomy yielded to full recovery. The recognition of such cases for whom surgical management can be avoided is primordial to avoid unnecessary laparotomy and its associated morbidity particularly in the critically ill.

Background. No previous study has investigated the adherence rate of North-African pulmonologists to the 2017-GOLD PTGs. Aims. To investigate the adherence rate of Tunisian pulmonologists to the 2017-GOLD PTGs and to identify the barriers to their adherence. Methods. This was a cohort study involving clinically stable COPD patients who presented to a pulmonology outpatient consultation. The patients were classified as having been appropriately and inappropriately (over- or undertreatment) treated for the GOLD group. Logistic regression was performed to determine the adherence barriers to the 2017-GOLD PTGs. Results. A total of 296 patients were included (88.1% males, mean age: 68±10 years; GOLD A (7.1%), B (36.1%), C (4.1%), and D (52.7%)). The pulmonologists’ adherence rate to the 2017-GOLD PTGs was 29.7%. There was a significant statistical difference between the adherence rates among the four GOLD groups (A: 19.0%, B: 20.6%, C: 8.3%, and D: 39.1%; p=0.001). Differences were statistically significant between the GOLD group D and groups B (p=0.001) and C (p=0.033). The multivariate analysis showed that age (odds ratio (OR): 0.968), socioeconomic level (high/medium vs. low; OR: 2.950), insurance type (national health insurance vs. others; OR: 2.851), and GOLD groups (A/B vs. C/D; OR: 3.009) significantly influenced the adherence rate to the 2017-GOLD PTGs. Conclusion. The adherence rate of Tunisian pulmonologists to the 2017-GOLD PTGs is low. It seems that the patients’ age, socioeconomic level, national health insurance coverage, and GOLD groups influenced their adherence.

IntroductionCerebral vasculitis is an uncommon life-threatening complication of community-acquired bacterial meningitis.Patient and methodsWe report the case of a 64-year-old woman with pneumococcal meningitis who developed parainfectious vasculitis causing ischaemic brain damage. Cerebral magnetic resonance imaging (MRI) confirmed the diagnosis. Clinical and radiological recovery after delayed addition of corticosteroid was achieved.DiscussionThis report shows that the onset of neurological deficits following pneumococcal meningitis can be caused by cerebral vasculitis. Underdosing with antibiotics and delayed adjunctive dexamethasone seem to favour this complication. There are no guidelines for treatment but high doses of steroids led to resolution in this case.LEARNING POINTSPneumococcal meningitis complicated by cerebral vasculitis can be treated with high-dose steroids.A repeat lumbar puncture is recommended to rule out relapsing or persistent infection in patients who deteriorate after 48 h of adequate antibiotic therapy.The cerebral vasculitis in our patient may have been caused by antibiotic underdosing and by delayed dexamethasone administration.

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