Cerebral vasculitis and lateral rectus palsy - two rare central nervous system complications of dengue fever: two case reports and review of the literature

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.

An unusual case of dengue fever in aneurysmal subarachnoid haemorrhage: diagnosis and management nuances

BACKGROUND

Dengue fever is highly prevalent in the Asia-Pacific region. Here we present an unusual case of dengue fever in a patient with a ruptured cerebral aneurysm causing subarachnoid (SAH) and intraventricular haemorrhage (IVH) and discuss the implications of dengue-related thrombopathies on the management of SAH and its complications.

CASE REPORT

A 56-year-old female with a two-day history of high-grade pyrexia and myalgia presented with sudden-onset drowsiness (presenting Glasgow Coma Scale, GCS: E1V1M4). Imaging revealed extensive SAH and IVH due to a ruptured right middle cerebral artery (MCA) aneurysm, with extensive vasospasm. Blood test revealed thrombocytopenia and a positive NS-1 antigen. She subsequently suffered from two episodes of re-rupture of the aneurysm and elevated intracranial pressure which required a decompressive craniectomy in addition to coilingof the MCA aneurysm. Cerebral perfusion and rheology were maintained with the triple-H therapy. Her GCS improved to E4V1M6, but remained aphasic.

DISCUSSIONS

Thrombocytopenia and deranged platelet functions in dengue infection might affect the stability of clot and increase the risk of re-rupture of aneurysm. Immediate securement of the aneurysm was paramount. In cases of severe dengue, plasma leakage could lead to intravascular depletion, and coupled with haemoconcentration and hypotension would further increase the risk for vasospasm.

Rectus Sheath Hematoma in a Recovering Dengue Patient: A Case Report

A 63-year-old male patient recovering from dengue came to our department for contrast-enhanced computed tomography (CECT) for the evaluation of abdominal pain. An ultrasound performed in the periphery diagnosed him with a rectus abscess. The CECT evaluation done in our department clarified that the collection in his rectus sheath was hemorrhagic and not infective, as previously thought. The patient was managed conservatively and recovered without complications. Like most infectious diseases, dengue is a disease of tropical countries. System-wise data collection processes are inadequate in many developing countries, which means complications and adverse effects of common diseases are not adequately captured. Furthermore, resource limitations restrict the availability of more expensive diagnostic tests to central locations. Peripherally located regions with lower purchasing capacity have greater access to relatively inexpensive tests. This causes deficits in the management of some common disease entities, like dengue. Considering these issues, it is important to optimize healthcare testing for low-resource settings. This can only be achieved with adequate sensitization of healthcare providers in diagnosis and management.

The Immediate Onset of Isolated and Unilateral Abducens Nerve Palsy Associated with COVID-19 Infection: A Case Report and Literature Review

Cranial nerve palsy associated with coronavirus disease 2019 (COVID-19) is rare. We herein report the first Asian case of the immediate onset of isolated and unilateral abducens nerve palsy (ANP) accompanied with COVID-19 infection. A 25-year-old man developed diplopia one day after the COVID-19 symptom onset. Neurological examination revealed limitation of left eye abduction without ataxia and hyporeflexia. Negative anti-ganglioside antibody results and mild albuminocytological dissociation were noted. The patient was diagnosed with left ANP accompanied by COVID-19 infection. The ANP spontaneously recovered without treatment. ANP can develop during the early phase of COVID-19 infection and adversely affect patients' quality of life.

Case Report: Dengue Hemorrhagic Fever with Ischemic Stroke

Several neurological manifestations are recognized in dengue infection, but stroke is a rare complication. We report a case of ischemic stroke in a patient with dengue hemorrhagic fever. A 52-year-old previously healthy male presented with a history of fever for 2 days, and left-sided weakness and numbness of sudden onset. MRI scanning showed a right-sided thalamic lacunar infarct. Diagnosis of dengue fever was made based on leuco-thrombocytopenia, positive dengue nonstructural protein-1 (NS-1) antigen, and positive dengue IgM antibodies. Severity of limb weakness correlated with the critical phase of dengue hemorrhagic fever (DHF). He was discharged home with good recovery from neurological symptoms and disability. Strokes are rare in dengue, and are mainly hemorrhagic strokes related to thrombocytopenia. Ischemic stroke is even rarer. More evidence is needed for confirmation of dengue as a pathogenic mechanism of ischemic stroke.

Herpes Simplex Virus-2 Meningoencephalitis With Abducens Nerve Palsy With Literature Review

Herpes simplex virus (HSV), a human alpha herpes virus, is responsible for most infections caused by herpes viruses worldwide. Among the herpes simplex viruses, both HSV 1 and 2 cause significant morbidity. HSV-2 accounts for most genital infections with extragenital complications involving the groin, thigh, or other pelvic areas. HSV-2 is the leading viral cause of sexually transmitted diseases. Viral dissemination via the blood or the cutaneous route during primary infection can affect joints, liver, lungs, spinal cord, and brain. HSV-2, by nature of its higher reactivation frequency, leads to clinical reactivation or subclinical shedding, resulting in increased transmission risk during unprotected sexual encounters. HSV-2 reactivation can result in lesions involving the fingers, skin, eyes, brain, and visceral organs such as the esophagus, lung, and liver. Ocular involvement results in keratitis, blepharitis, conjunctivitis, and rarely necrotizing retinitis. Oculomotor cranial nerve involvement by HSV is a rare entity even in patients with human immunodeficiency virus infection. Clinical features associated with reactivation are seen in primary infections, especially in children and adolescents. A medical literature search resulted in a few cases caused by a varicella-zoster virus but none by HSV. Here we describe a young female with a newly diagnosed meningoencephalitis and abducens nerve palsy (first case) due to a primary HSV infection. She came to the emergency department with headache, confusion, abnormal behavior and later developed diplopia as an inpatient. She was treated successfully with two weeks of acyclovir.

Isolated abducens nerve palsy - A rare clinical presentation in dengue haemorrhagic fever

Dengue fever is the most prevalent flavivirus infection in tropical and subtropical areas of the world. It is transmitted by the haematophagous mosquito Aedes aegypti, and it manifests clinically as classical dengue fever, dengue haemorrhagic fever and dengue shock syndrome. Rarely, dengue can be associated with neurophthalmic manifestations. We present the case of a 21-year-old woman, suffering from dengue with an isolated abducens nerve palsy.

Case report: Mononeuritis multiplex in the course of dengue fever

Background

Dengue fever usually presents as a self-limiting acute febrile illness with worsening thrombocytopenia, with a small minority of patients developing hemorrhagic or life-threatening complications. Organ specific manifestations like myocarditis, acalculous cholecystitis, encephalitis has been described but are uncommon presentations. Even more rarely, such manifestations are the presenting complaint of Dengue fever. In this case report, we highlight a case of Dengue fever where unrelated neuropathies were the presenting complaint.

Case presentation

An elderly man presents with 1 day of diplopia and left foot drop, associated with 2 days history of fever. A decreasing white cell count (WBC) and platelet on the 2nd day of admission prompted Dengue virus to be tested and a positive NS-1 antigen was detected, confirming the diagnosis of Dengue fever. He was treated with supportive treatment with a short duration of intravenous fluids recovered uneventfully and was discharged 6 days after admission with almost full resolution of diplopia and partial resolution of left foot drop. Left foot drop recovered completely 2 weeks later.

Conclusion

Neurological manifestations can be the presenting symptoms in Dengue fever, a diagnosis which should be borne in mind when such symptoms present in patients from endemic areas or in returning travellers from these areas.

A Case Report on Dengue Encephalitis With Optic Neuropathy

The dengue virus is a type of Flavivirus, responsible for causing dengue fever. It mostly prevails in tropical and subtropical countries, with Southeast Asia reporting the greatest disease burden. The virus can affect a multitude of organ systems and the disease spectrum varies from a mild flu-like illness to severe dengue hemorrhagic fever or dengue shock syndrome. Two serotypes, DENV-2 and DENV-3, have been most frequently associated with neurological complications. We report a case of a 19-year-old male presented with signs and symptoms of encephalitis and optic neuropathy, following a diagnosis of dengue fever. Our diagnosis was supported by findings from brain MRI, electroencephalogram, fundoscopy, and a visual evoked potential test. A high-dose intravenous steroid therapy was given in pulses, which resulted in complete visual and neurological recovery. Dengue fever can present with atypical findings due to its propensity to affect multiple organ systems throughout the body. Neurological involvement is not uncommon and hence, clinicians should be aware of such systemic manifestations in order to diagnose promptly. Effective and timely treatment can reduce associated morbidity and result in complete recovery.

Dengue infection in mice inoculated by the intracerebral route: neuropathological effects and identification of target cells for virus replication

Dengue is an important arboviral infection, causing a broad range symptom that varies from life-threatening mild illness to severe clinical manifestations. Recent studies reported the impairment of the central nervous system (CNS) after dengue infection, a characteristic previously considered as atypical and underreported. However, little is known about the neuropathology associated to dengue. Since animal models are important tools for helping to understand the dengue pathogenesis, including neurological damages, the aim of this work was to investigate the effects of intracerebral inoculation of a neuroadapted dengue serotype 2 virus (DENV2) in immunocompetent BALB/c mice, mimicking some aspects of the viral encephalitis. Mice presented neurological morbidity after the 7^th day post infection. At the same time, histopathological analysis revealed that DENV2 led to damages in the CNS, such as hemorrhage, reactive gliosis, hyperplastic and hypertrophied microglia, astrocyte proliferation, Purkinje neurons retraction and cellular infiltration around vessels in the pia mater and in neuropil. Viral tropism and replication were detected in resident cells of the brain and cerebellum, such as neurons, astrocyte, microglia and oligodendrocytes. Results suggest that this classical mice model might be useful for analyzing the neurotropic effect of DENV with similarities to what occurs in human.

Dengue hemorrhagic fever presenting as encephalitis: a case report

BACKGROUND

Dengue fever and dengue hemorrhagic fever incidence is increasing in Sri Lanka, especially among the young population. Uncommon presentations of this common illness make diagnostic dilemmas and can delay standard treatment which leads to unfavorable outcomes.

CASE PRESENTATION

An 18-year-old Sri Lankan Sinhalese boy presented with a history of 1 day of fever and an episode of seizure followed by left-side hemiparesis. He was diagnosed to have dengue complicated by dengue hemorrhagic fever and recovered with minimal residual weakness. He presented with neurological symptoms; cerebrospinal fluid analysis, electroencephalogram, and magnetic resonance imaging showed evidence of encephalitis. Positive dengue antigen and antibody in serum and cerebrospinal fluid with the exclusion of other possible etiologies confirmed parainfectious dengue encephalitis. He was started on sodium valproate 200 mg 8 hourly and made a slow neurological recovery with mild residual weakness (grade 4+ power) in his left upper limb at 2 months with intensive supervised physiotherapy.

CONCLUSION

Standard national guideline-based management of dengue illness has significantly reduced its mortality rates in Sri Lanka. However, uncommon presentations of a common illness often cause diagnostic dilemmas. Hence, reporting of these presentations and knowing the epidemiologic patterns of the disease help physicians to arrive at the correct diagnosis even though they do not have sophisticated serological investigations. Overall, this can improve the quality of health care and reduce mortalities, especially in a resource-poor setup.

Multifocal motor neuropathy presenting as a post-infectious complication of dengue: a CASE report

Background

Dengue infection is an endemic illness in the tropics and it is associated with a wide variety of post infectious complications. With the increasing prevalence of dengue infection in endemic regions, post-infectious neurological complications following dengue infection are now been reported more frequently. We report a patient who developed multifocal motor neuropathy (MMN) with conduction blocks following dengue infection during the immediate post-infectious period. MMN is a rare neurological disorder with an autoimmune etiology and to best of our knowledge this is the first reported case of MMN occurring following dengue infection as a post dengue neurological complication.

Case presentation

A 20 year old Sri Lankan male who was treated for serologically confirmed dengue infection presented to us with 1 month history of bilateral hand weakness which has started 5 days after the dengue infection (5 days after the discharge). On examination he had asymmetrical motor weakness of the hands and to a lesser degree in feet. There was no sensory impairment. Nerve conduction studies confirmed MMN with conduction blocks. He was started on intravenous immunoglobulin therapy for which he showed a good response.

Conclusion

The authors report the first case of MMN complicating dengue fever in a previously healthy male from Sri Lanka. Thus it should be borne in mind that although rare, MMN can occur as a post-infectious complication of dengue fever.

Case Report: Right Hemispheric Neuroimaging Abnormalities in a Patient with Dengue Encephalopathy

Dengue encephalitis and dengue encephalopathy are frequent neurological complications of systemic dengue virus infection. Neuroimaging is normal in approximately 50% of patients. Common imaging abnormalities involve periventricular structures, including the basal ganglion, thalamus, and periventricular white matter. We describe an unusual case of dengue encephalopathy with unilateral imaging abnormalities involving the right cerebral hemisphere and mimicking the involvement of the right middle cerebral artery.