Infectious mononucleosis (IM) is caused by Epstein-Barr virus (EBV), and the condition is characterized by sore throat, fever, lymphadenopathy, and atypical lymphocytosis. These infections are common in early childhood, with a second peak occurring in late adolescence. EBV is spread by contact with oral secretions. Most cases of IM are self-limited. However, there are associated complications, some of which can be serious and fatal. We report the case of a 20-year-old man with splenic infarction and exuberant peritonsillar abscess secondary to an EBV infection. This case highlights the importance of accurate diagnoses and frequent monitoring in IM patients, given the risk of airway obstruction.

Carotid-cavernous fistulas are abnormal communications between the carotid arteries and the cavernous sinus. They can be spontaneous, which is rare, or acquired, most often post-traumatic. We describe the case of a 59-year-old woman with complaints of right-sided red eye and blurred vision that did not improve with antibiotic treatment for bacterial conjunctivitis, progressing to what appeared to be post-septal cellulitis. The patient had exuberant chemosis, diplopia, VI cranial nerve palsy, and elevated intraocular pressure in the right eye. Computed tomography of the orbits showed right-sided thickening of the soft tissues of the upper eyelid and the medial and lateral rectus muscles, and an enlargement of the ipsilateral superior ophthalmic vein. However, antibiotics did not cause any kind of improvement. After a laborious diagnostic march, the diagnosis of a rare case of Barrow type B spontaneous carotid-cavernous fistula was confirmed. The patient underwent confirmatory angiography with endovascular treatment at the same time, showing rapid improvement after the procedure, without any sequelae. It is of great importance that clinicians are alert to this diagnosis, as diagnostic and therapeutic delay can lead to severe ocular compromise. In patients with a presumptive diagnosis of conjunctivitis and/or orbital cellulitis that does not improve with antibiotic treatment, the differential diagnosis with this rare entity should be considered, so that the appropriate treatment can be timely instituted.

Quincke's disease is a very rare form of upper airway angioedema, and it is characterized by a well-localized edematous reaction. Its epidemiology is not documented due to the rarity of this condition. Causes include allergic reactions, infectious diseases, and trauma, among others. This article describes a rare case of a 27-year-old man who presented to the Emergency Department with isolated uvular edema associated with cocaine exposure.

Left ventricular noncompaction (LVNC) is characterized by a bilayered appearance of the myocardium with excessive trabeculations and deep intertrabecular recesses. Manifestations of this condition are widely variable, ranging from incidental findings in asymptomatic individuals to symptomatic heart failure, conduction abnormalities, tachyarrhythmia, and sudden cardiac death. Heart failure, ventricular arrhythmias, and systemic embolisms are the most frequent cardiovascular complications.We describe a case of a 53-year-old woman who presented to the emergency department with acute presentation of previously unknown heart failure with reduced ejection fraction and was diagnosed with LVNC. During hospitalization, the patient presented a defibrillated cardiac arrest rhythm, which was resuscitated after six minutes, and then treated with the placement of an implantable cardioverter defibrillator. After two years of follow-up with optimized medical therapy, the patient currently is asymptomatic and with a preserved ejection fraction.

Mycoplasma pneumoniae (MP) is a common etiologic agent involved in community-acquired atypical bacterial pneumonia. In severe cases, M. pneumoniae can cause cavitated lung lesions. We describe the case of a 55-year-old male seen at the emergency department with complaints of cough, fever, dyspnea, pleuritic chest pain, nausea, anorexia, asthenia, and night sweats. Cavitated lesions in the upper lobes of both lungs were documented on thoracic computed tomography (CT). An extensive investigation ruled out several infectious and non-infectious causes. The only positive result was a high immunoglobulin M (IgM) titer for M. pneumoniae. The patient was treated with azithromycin and exhibited rapid clinical improvement. Three months later, a repeat thoracic computed tomography showed the resolution of the cavitated lesions. In this rare case of M. pneumoniae pneumonia with cavitated lesions, early identification of the etiologic agent and prompt antibiotic therapy led to the resolution of the cavitated lung lesions.