An identical postzygotic HRAS mutation was shown to be present in both keratinocytic epidermal nevus and thymoma and to be associated with bone lesions and hypophosphatemia due to elevated FGF23 levels. These may all be related to the HRAS mutation.
Assessment of the ability to maintain wakefulness, although very important both for research and for clinical purposes, is still equivocal. The current gold standard is considered the Maintenance of Wakefulness Test (MWT), although there are two different potential protocols to perform it and the normal reference range has been determined on selected populations. The effect of potential "penalty" on failing the test (i.e., presenting sleepiness) has not been seriously studied. We therefore planned this study to examine the effect of motivation on the MWT results in a potentially sleepy population. We hypothesized that with the knowledge that participants may lose their driving license if they fail the test, the results would indicate significantly less sleepiness than reported for other populations. Fifty-four consecutive subjects at high risk of sleepiness referred to the sleep laboratory for evaluation of their ability to maintain wakefulness were studied. All were referred by the National Council for Driving Safety, knowing that if they failed the test, their driving license would not be renewed. Referral reasons were previously diagnosed: obstructive sleep apnea (OSA; 43%), sleep-related accident (7%), or other causes to suspect sleepiness. All underwent a full-night polysomnography (PSG) followed by MWT, five trials of 20 min each (MWT20). Of the 54 participants, 13 were treated for OSA and 28 had untreated OSA, 21 of them had severe OSA (Respiratory Disturbance Index > 30/h). Seventy-four percent of the participants had a BMI >30 kg/m2. Only 5 of the participants fell asleep in any of the MWT trials (one to five trials), which could not be predicted by severity of OSA, age, BMI, or variables derived from the previous night PSG. Of the 21 patients with severe untreated OSA, only 1 patient fell asleep during the MWT20. We conclude that motivation profoundly affects the MWT results, raising the question what should be considered normal or abnormal when sleepy results may cause penalty or other practical implications. In addition, we believe that these results suggest that for renewal of driving license purposes, the MWT20 is insufficient. We speculate that MWT40, with tighter cutoff threshold, would be a more effective tool.
Scientific inveStigAtionSStudy Objectives: Objective assessment of the ability to maintain wakefulness, although very important, is still equivocal. A recent study from our lab has shown that the Maintenance of Wakefulness Test (MWT), when performed with the 20-minute protocol (MWT20), is unreliable in assessing patients who are highly motivated to maintain wakefulness. In this study, we sought to examine whether the 40-minute protocol (MWT40) is a better tool in assessing such individuals. Methods: One hundred sixty-four consecutive subjects referred to our sleep lab by the Medical Institute for Driving Safety were studied. All subjects underwent a full-night polysomnogram followed by an MWT, 4 trials of 40 minutes each. All subjects knew that if they failed the wakefulness test their driving license would be revoked.Results: Forty-one subjects out of 164 (25%) fell asleep at least once. Of 39 subjects with severe obstructive sleep apnea, (respiratory disturbance index > 40/h), 19 fell asleep (48.7%). Of 13 subjects with a minimum oxygen saturation level below 65%, 7 fell asleep (53%). In the MWT20, only 7% of patients with severe obstructive sleep apnea fell asleep at least once. Conclusions: We conclude that the MWT40 is superior to the MWT20 in detecting difficulties maintaining wakefulness in a highly motivated population. However, our results yield a significantly lower detection of difficulties maintaining wakefulness than those reported in healthy subjects, suggesting that the MWT40 is also highly affected by motivation. We believe that, for a highly motivated population (such as for a driver's license validation), different average sleep-latency threshold should be used than in general population.
We aimed to describe a case of neovascular glaucoma (NVG) as a first presenting sign of catastrophic antiphospholipid syndrome (CAPS) with heart valve aseptic vegetations known as Libman-Sacks endocarditis. A 39-year-old man was referred for left eye decreased visual acuity and pain, upon examination left eye high intraocular pressure; rubeosis iridis of both eyes (BE); and prominent retinal ischemia. Clinical and fluorescein angiography findings established the diagnosis of left eye NVG with vaso-occlusive disease in BE. Magnetic resonance imaging of the head showed widespread ischemic lesions and hemorrhagic foci. The transesophageal echocardiogram showed 2 big mitral valve lesions consistent with the diagnosis of Libman-Sacks endocarditis. Laboratory and clinical diagnosis of CAPS and suspected SLE was confirmed, and treatment with anticoagulants and IV steroids was initiated. This case demonstrates that severe vaso-occlusive retinopathy with severe brain ischemia should raise the suspicion of systemic autoimmune pro-coagulative diseases with heart valve aseptic vegetations.
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