Unmasking the Mimic: Radionecrotic Lesion Masquerading as Brain Neoplasia on Magnetic Resonance Imaging.

Corpus callosotomy is a therapeutic approach for drug-resistant epilepsy, with positive outcomes observed in managing atonic seizures. Despite a decline in its usage, radiosurgical callosotomy remains a viable option for drug-resistant epilepsy due to its low risks of post-radiation neoplasia, albeit not with exceptions. Brain radionecrosis is characterized by tissue death and vascular endothelial damage following the procedure. Despite the low risk of intracranial secondary malignancy associated with radiation in some cases, post-radiation lesions might present with distinct characteristics needing a thorough diagnostic approach. Herein, we present a unique case of a patient with focal epilepsy who developed a radionecrotic lesion following radiosurgical callosotomy, affecting the anterior cingulate cortex, and mimicking a central nervous system (CNS) tumor. Molecular imaging techniques, including 18-fluorodeoxyglucose positron emission tomography/computed tomography (18-FDG PET/CT) and 11C-acetate PET/CT scans, were employed to differentiate the lesion from a tumor. This case underscores the importance of considering radionecrosis as a differential diagnosis in patients who undergo radiosurgical callosotomy presenting with ring-like enhancement lesions on magnetic resonance imaging (MRI).

Pathological Thoracic Vertebral Fractures Secondary to Achromobacter denitrificans: A Case Report.

Vertebral fractures remain a diagnostic challenge nowadays. The first and most common diagnosis needed to be ruled out is osteoporosis. Other diagnoses to rule out involve pathological fractures. Pathological fractures are a group of pathologies that result in a spine fracture as part of an underlying disease process that affects the spine. This group includes Paget's disease, tumors, osteomyelitis, and vertebral compression fractures. Fractures secondary to vertebral osteomyelitis are presented as collapsed vertebral bodies secondary to bone destruction and the formation of lytic lesions. Clinical presentation includes severe back pain refractory to analgesic therapy, persistent unexplained fever, and leukocytosis without any other obvious focus of infection. In cases like the one presented here, early biopsy and culture should be performed on every patient that fits these criteria. However, as it presents unspecific symptoms most of the time, it is not suspected, and therefore it is associated with high morbidity and mortality.

Ischemic Stroke as an Initial Manifestation of Antiphospholipid Syndrome in an Adolescent: A Case Report.

Cerebrovascular diseases in pediatric patients are relatively rare. Ischemic stroke in adolescents is associated with a poor prognosis. The most common causes include systemic diseases, such as heart disease and hypercoagulation disorders. It is important to mention that one of the most common acquired hypercoagulation states is the antiphospholipid syndrome (APS). Patients with this disease may present stroke as the first clinical manifestation, which not only increases morbidity in these patients but presents a diagnostic challenge. This case presents one example of how APS can present as a pediatric stroke. The diagnostic approach should always be through the presence of specific antibodies accompanied by the presence of a thromboembolic episode proven by catheterization or an imaging study. In the brain, the preferred imaging study is magnetic resonance imaging. Management is based on anticoagulation therapy and continuous monitoring in the intensive care unit.

Reactive Arthritis as a Consequence of Infection by Clostridium difficile in a Pediatric Patient.

Reactive arthritis (RA) is the development of a sterile inflammatory arthritis usually associated with a previously known infection, most commonly from the gastrointestinal or urogenital tract. The diagnosis is clinical, based on the presence of acute oligoarticular arthritis of larger joints developing within two to four weeks of the infection. However, in some cases where the infection is not clear, the diagnosis is a challenge, like in the case presented here. We must always rule out past infections as a cause of arthritis by directly asking about the presence of symptomatology associated with it, presented in the past few weeks. It's important to emphasize that human leukocyte antigen B27 (HLA-B27) should not be used as a diagnostic tool, and it always needs to be correlated with the clinical features. There is no confirmed evidence in the literature that is in favor of prescribing antibiotic therapy during an acute presentation of RA as it usually presents after the infection is cured.

Guillain-Barré Syndrome in an Immunocompromised Patient: A Case Report.

Guillain-Barré syndrome (GBS) in post-transplant patients is a rare clinical presentation. Although in the literature this neurological condition has been mainly associated with viral infections secondary to immunosuppression, GBS should not only be suspected in patients with an acute condition. It is essential to always rule out a viral or bacterial cause, looking for the most common sources, i.e., urinary, respiratory, and gastrointestinal. The diagnosis of GBS is clinically based, and its management is based on the use of intravenous immunoglobulin (IVIG) or plasma exchange. Its timely diagnosis allows treatment to be started early, thus improving the prognosis of these patients and reducing the time of hospitalization and complications associated with it. This report shows how an interdisciplinary approach is vital in such cases, as both the precipitant and the disease must be managed to decrease the morbidity and mortality associated with this condition. It is crucial to evaluate the benefits and risks of withdrawing immunosuppressive treatment in post-transplant patients, and being able to recognize when restarting them is indicated.