Relapsing-remitting multiple sclerosis patients exhibit differential natural killer functional subpopulations.

BACKGROUND: Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS) and has been known as T-cell mediated. However, the contribution of multiple cell types, notably natural killer (NK) cells, has also been reported. AIM: To quantify circulating total NK cells and its subpopulations, CD56 dim and bright, and to characterize the functional phenotype and IFN-γ and TNF-α production in relapsing-remitting patients treated with IFN-ß and in apparently healthy controls. RESULTS: CD56bright NK cells were found to be the least represented subpopulation. In relapse patients, the frequencies of IFN-γ-producing NK cells and their subpopulations were significantly decreased. In remission patients, CD56dim NK cells expressed high levels of HLA-DR and CD54. CONCLUSION: These results suggest that remission RRMS patients, although in an inactive stage of MS, present circulating NK cells with an activation phenotype, supporting the idea that NK cells may be relevant mediators in the MS pathophysiology.

Epipericardial fat necrosis in chest CT and MRI: a case report of an unusual cause of chest pain associated with the initial diagnosis of undifferentiated connective tissue disease.

BACKGROUND: Epipericardial fat necrosis (EFN) is a benign and self-limited condition of unknown cause with a good prognosis, usually affecting otherwise healthy patients. Clinically, it presents with severe acute left pleuritic chest pain, often leading the patient to the Emergency Room (ER). CASE PRESENTATION: A 23-year-old male, smoker (5 pack-years), was evaluated in the ER due to left pleuritic chest pain, worsening with deep breathing and Valsalva maneuver. It was not associated with trauma and did not present other symptoms. The physical examination was unremarkable. The arterial blood gases while breathing room air and the laboratory tests, including D-dimers and high-sensitivity cardiac Troponin T, were normal. The chest radiograph, electrocardiogram, and transthoracic echocardiogram showed no abnormalities. A computed tomography (CT) pulmonary angiogram showed no signs of pulmonary embolism but depicted at the left cardiophrenic angle a focal 3 cm ovoid-shaped fat lesion with stranding and thin soft tissue margins, consistent with necrosis of the epicardial fat, which was confirmed by magnetic resonance (MRI) of the chest. The patient was medicated with ibuprofen and pantoprazole, with clinical improvement in four weeks. At a two-month follow-up, he was asymptomatic and presented radiologic resolution of the inflammatory changes of the epicardial fat of the left cardiophrenic angle on chest CT. Laboratory tests revealed positive antinuclear antibodies, positive anti-RNP antibody, and positive lupus anticoagulant. The patient complained of biphasic Raynaud's phenomenon initiated five years ago, and a diagnosis of undifferentiated connective tissue disease (UCTD) was made. CONCLUSIONS: This case report highlights the diagnosis of EFN as a rare and frequently unknown clinical condition, which should be considered in the differential diagnosis of acute chest pain. It can mimic emergent conditions such as pulmonary embolism, acute coronary syndrome, or acute pericarditis. The diagnosis is confirmed by CT of the thorax or MRI. The treatment is supportive and usually includes non-steroidal anti-inflammatory drugs. The association of EFN with UCTD has not been previously described in the medical literature.