Cerebellar syndrome in Plasmodium falciparum malaria

Acute Cerebellar Inflammation and Related Ataxia: Mechanisms and Pathophysiology

The cerebellum governs motor coordination and motor learning. Infection with external microorganisms, such as viruses, bacteria, and fungi, induces the release and production of inflammatory mediators, which drive acute cerebellar inflammation. The clinical observation of acute cerebellitis is associated with the emergence of cerebellar ataxia. In our animal model of the acute inflammation of the cerebellar cortex, animals did not show any ataxia but hyperexcitability in the cerebellar cortex and depression-like behaviors. In contrast, animal models with neurodegeneration of the cerebellar Purkinje cells and hypoexcitability of the neurons show cerebellar ataxia. The suppression of the Ca²⁺-activated K⁺ channels in vivo is associated with a type of ataxia. Therefore, there is a gap in our interpretation between the very early phase of cerebellar inflammation and the emergence of cerebellar ataxia. In this review, we discuss the hypothesized scenario concerning the emergence of cerebellar ataxia. First, compared with genetically induced cerebellar ataxias, we introduce infection and inflammation in the cerebellum via aberrant immunity and glial responses. Especially, we focus on infections with cytomegalovirus, influenza virus, dengue virus, and SARS-CoV-2, potential relevance to mitochondrial DNA, and autoimmunity in infection. Second, we review neurophysiological modulation (intrinsic excitability, excitatory, and inhibitory synaptic transmission) by inflammatory mediators and aberrant immunity. Next, we discuss the cerebellar circuit dysfunction (presumably, via maintaining the homeostatic property). Lastly, we propose the mechanism of the cerebellar ataxia and possible treatments for the ataxia in the cerebellar inflammation.

Delayed cerebellar ataxia, A rare post-malaria neurological complication: Case report and review of the literature

Delayed cerebellar ataxia (DCA) is a rare post-malarial neurological complication with unknown pathomechanism characterized by its self-limiting course and favorable outcome. We report a case of DCA following an uncomplicated Plasmodium falciparum infection in a 30-year old Swiss traveler returning from Cameroon and discuss the case in light of the published literature.

Video Anthology of Movement Disorders Due to Infections in South Asia

South Asia, encompassing many populous countries including India, Pakistan, and Bangladesh, is home to a wide variety of infectious diseases several of which are disproportionately prevalent, endemic or distinctive to the region. These result in considerable morbidity and mortality, which can be greatly reduced through public-health measures, timely diagnosis and treatment. Some of these infectious diseases have neurological manifestations including movement disorders either due to the pathogen being neuroinvasive or via an immune-mediated response. For diseases such as Japanese encephalitis, movement disorders are the primary manifestation while for others, they can be a presenting feature. Thus, recognizing these movement disorders is often crucial to the diagnosis of the particular infection, and/or to exclude infection as a cause and arrive at the correct alternate diagnosis. Once diagnosed, the infection-related movement disorders are treated by targeting the infectious agent, or symptomatically. In this article, we describe and illustrate a variety of movement disorders that are seen in patients infected by viruses, bacteria and parasites in South Asia. This would be of value to neurologists practicing in the region and, with the increasing ease in movement of people and pathogens, those practicing elsewhere.

Acute disseminated encephalomyelitis, a rare post-malaria neurological complication: Case report and review of the literature

There are four neurological complications that can occur after malaria treatment at a time when the patient is aparasitaemic: delayed cerebellar ataxia, acute inflammatory demyelinating polyneuropathy, post-malaria neurological syndrome and acute disseminated encephalomyelitis (ADEM). The authors describe a case of a 54-year-old male who presented with encephalopathy and generalized seizures forty-three days after complete recovery from acute malaria by Plasmodium falciparum. Diagnosis of post-malaria ADEM was made based on the acute onset of the neurological symptoms, characteristic findings in magnetic resonance imaging of the brain and prompt response to steroid therapy. ADEM is an autoimmune demyelinating disease of the central nervous system that usually arises after an infection or vaccination. Its occurrence after malaria infection is relatively rare, and to the best of our knowledge there are only thirteen cases described in the literature.

Case reports on atypical presentation of Plasmodium falciparum malaria in pediatric patients

Variable atypical symptoms are commonly observed in malaria caused by Plasmodium falciparum especially in endemic tropical nations such as India. Nystagmus is observed following involvement of the cerebellum especially during the postrecovery phase. While psychotic features such as severe agitation, hallucination, paranoia may be the early symptoms of falciparum malaria among pediatric patients, urticaria with or without fever can be the initial manifestation of the disease. As the morbidity and mortality of severe malaria are very high in India, these atypical presentations should be considered during diagnosis. We believe our report on atypical cases of falciparum malaria will sensitize doctors and health personnel about rare presentations in children and help in early diagnosis and management to reduce the severity and death toll due to the disease.

Rabies, tetanus, leprosy, and malaria

The developing world is still endemic to rabies, tetanus, leprosy, and malaria. Globally more than 55000 people die of rabies each year, about 95% in Asia and Africa. Annually, more than 10 million people, mostly in Asia, receive postexposure vaccination against the disease. World Health Organization estimated tetanus-related deaths at 163000 in 2004 worldwide. Globally, the annual detection of new cases of leprosy continues to decline and the global case detection declined by 3.54% during 2008 compared to 2007. Malaria is endemic in most countries, except the US, Canada, Europe, and Russia. Malaria accounts for 1.5-2.7 million deaths annually. Much of the disease burden related to these four infections is preventable.

Cerebellar atrophy in falciparum malaria

Severe neurological complications are associated with falciparum malaria. We describe the case of an eight-year-old male child with severe falciparum malaria with high-level parasitemia and severe thrombocytopenia. There were features of abnormal gait, speech difficulty and altered behavior pattern during the recovery phase. This occurred even after receiving antimalarial therapy. MRI showed bilateral cerebellar atrophy.

Postmalaria neurologic syndrome: a case report

Neurologic signs and symptoms are common in acute malarial infection. However, after the parasites have been cleared from the blood and patients recover full consciousness, neurologic or psychiatric symptoms may occur or recur within 2 months after the acute illness. This phenomenon is called "postmalaria neurologic syndrome" (PMNS). We present a 50-year-old man who returned from the Republic of Malawi and soon developed Plasmodium falciparum malaria. Cerebral malaria, renal failure, hepatic failure, diffuse intravascular coagulation with thrombocytopenia, and upper gastrointestinal bleeding were noted during the acute stage. He was admitted to the infectious diseases ward and treated for 3 weeks. He was free from clinical general symptoms and parasites in blood smear when discharged. However, 2 weeks after discharge, he began to experience severe headache, dizziness, diplopia, mild hand tremor, unsteady gait, and easy falling. When readmitted to the neurologic ward, he presented with irritability, delirium, visual hallucination, and strange behavior. Neurologic examination was normal except for mild general weakness and evident truncal ataxia when walking. Brain magnetic resonance imaging revealed no structural lesions, and electroencephalography showed diffuse cortical dysfunction. Cerebral spinal fluid profile exhibited cytoalbuminologic dissociation. Brain single photon emission computed tomography showed diffuse cerebral parenchymal disorder. Nerve conduction studies revealed early sensory predominant polyneuropathy. The unsteadiness persisted for the initial 2 weeks of hospitalization until corticosteroid was administered. Intravenous methylprednisolone (80 mg/day) was continued for 3 days, followed by oral prednisolone (45 mg/day). His unsteadiness improved gradually after medication, and he absconded from the hospital on the 9th day of corticosteroid treatment with clear consciousness and free ambulation. The manifestation of PMNS is diverse and may present as an acute confusional state or psychosis, generalized seizure, fine tremors, cerebellar syndromes, postural hypotension, or malarial polyneuritis. Although the neurologic syndrome is primarily self-limited in most cases, corticosteroid may be beneficial in reversing PMNS.