Case report: Mononeuritis multiplex in the course of dengue fever

Unilateral lateral rectus palsy following dengue: a case report

Introduction and importance

Dengue fever is a mosquito-borne viral infection presenting with high-grade fever and other constitutional symptoms.

Case presentation

This case report details a rare occurrence of lateral rectus palsy in an 18-year-old male subsequent to dengue infection. The patient initially presented with fever, a generalized tonic-clonic seizure (GTCS), and symptomatic hypoglycemia, leading to multiple organ dysfunction syndrome (MODS) necessitating intensive care. Remarkably, no haemorrhagic manifestations were observed. The MODS gradually resolved by the 12th day of admission, coinciding with the emergence of complaints about uniocular diplopia and right esotropia. Systemic examination, including a normal computed tomography (CT) head scan, did not reveal any abnormalities. Additionally, potential causes contributing to esotropia and diplopia were ruled out. The patient was subsequently managed expectantly for lateral rectus palsy following severe dengue. Follow-up assessments indicated a gradual improvement in esotropia and diplopia, and the patient was advised to continue the prescribed medications.

Conclusion

This is the first documented case report of paralytic squint post-severe dengue in Nepal, emphasizing the importance of considering it as a differential diagnosis in tropical regions with endemic dengue infections. The case report advocates early identification and treatment of ophthalmic issues, notably with prednisolone, to achieve favourable outcomes, as evidenced by improvements in visual acuity, esotropia, and diplopia during follow-ups. Further research is essential to determine optimal treatment strategies for such neurological complications associated with dengue fever.

Dengue virus infection and neurological manifestations: an update

Dengue virus is a flavivirus transmitted by the mosquitoes, Aedes aegypti and Aedes albopictus. Dengue infection by all four serotypes (DEN 1 to 4) is endemic globally in regions with tropical and subtropical climates, with an estimated 100-400 million infections annually. Among those hospitalized, the mortality is about 1%. Neurological involvement has been reported to be about 5%. The spectrum of neurological manifestations spans both the peripheral and central nervous systems. These manifestations could possibly be categorized into those directly related to dengue infection, i.e. acute and chronic encephalitis, indirect complications leading to dengue encephalopathy, and post-infectious syndrome due to immune-mediated reactions, and manifestations with uncertain mechanisms, such as acute transverse myelitis, acute cerebellitis and myositis. The rising trend in global dengue incidence calls for attention to a more explicit definition of each neurological manifestation for more accurate epidemiological data. The actual global burden of dengue infection with neurological manifestation is essential for future planning and execution of strategies, especially in the development of effective antivirals and vaccines against the dengue virus. In this article, we discuss the recent findings of different spectrums of neurological manifestations in dengue infection and provide an update on antiviral and vaccine development and their challenges.

Ischemic Stroke During Dengue Infection: A Report of 2 Cases

BACKGROUND Involvement of the central nervous system during infection with dengue virus (DENV) is recognized. However, ischemic stroke is rarely reported. Herein are described 2 cases of patients with ischemic stroke in which DENV infection was demonstrated. CASE REPORT The first patient was a 51-year-old woman that presented altered consciousness, monoparesis, facial palsy, dysarthria, Babinski sign, and syncope 7 days from the onset of fever. She had a history of carotid artery atherothrombosis and previous stroke. Magnetic resonance imaging (MRI) showed an acute infarction of the right middle cerebral artery. DENV was confirmed by the presence of NS1 and IgM in serum. The patient was treated with intravenous fluids and recovered well, with only right facial paresis still present at discharge. The second patient was a 50-year-old man who presented with headache, altered consciousness, and mutism after a febrile episode 1 week prior. This patient had a previous history of stroke, glioblastoma resection, epilepsy, hypothyroidism, and diabetes. MRI demonstrated a subacute ischemic event. The diagnosis of dengue was confirmed by serum NS1 and IgM and by RT-PCR in serum and cerebrospinal fluid. DENV-1 serotype was observed in serum and cerebrospinal fluid. The patient was treated with intravenous fluids and was discharged in good condition. In both patients, thrombocytopenia and leukopenia was demonstrated, and hemoconcentration was demonstrated in the second patient. CONCLUSIONS In tropical and subtropical countries, DENV infection can represent a potential cause of ischemic stroke in patients with a history of comorbidities, including stroke.

Modulating Neurological Complications of Emerging Infectious Diseases: Mechanistic Approaches to Candidate Phytochemicals

Growing studies are revealing the critical manifestations of influenza, dengue virus (DENV) infection, Zika virus (ZIKV) disease, and Ebola virus disease (EVD) as emerging infectious diseases. However, their corresponding mechanisms of major complications headed for neuronal dysfunction are not entirely understood. From the mechanistic point of view, inflammatory/oxidative mediators are activated during emerging infectious diseases towards less cell migration, neurogenesis impairment, and neuronal death. Accordingly, the virus life cycle and associated enzymes, as well as host receptors, cytokine storm, and multiple signaling mediators, are the leading players of emerging infectious diseases. Consequently, chemokines, interleukins, interferons, carbohydrate molecules, toll-like receptors (TLRs), and tyrosine kinases are leading orchestrates of peripheral and central complications which are in near interconnections. Some of the resulting neuronal manifestations have attracted much attention, including inflammatory polyneuropathy, encephalopathy, meningitis, myelitis, stroke, Guillain-Barré syndrome (GBS), radiculomyelitis, meningoencephalitis, memory loss, headaches, cranial nerve abnormalities, tremor, and seizure. The complex pathophysiological mechanism behind the aforementioned complications urges the need for finding multi-target agents with higher efficacy and lower side effects. In recent decades, the natural kingdom has been highlighted as promising neuroprotective natural products in modulating several dysregulated signaling pathways/mediators. The present study provides neuronal manifestations of some emerging infectious diseases and underlying pathophysiological mechanisms. Besides, a mechanistic-based strategy is developed to introduce candidate natural products as promising multi-target agents in combating major dysregulated pathways towards neuroprotection in influenza, DENV infection, ZIKV disease, and EVD.