Atypical presentation of biotinidase deficiency: masquerading neuromyelitis optica spectrum disorder.

Biotinidase deficiency (BTD) is a treatable, inherited metabolic disorder commonly characterised by alopecia, dermatitis, seizures and developmental delay. It can also manifest as optic neuritis and myelitis; however, these are infrequently described in the literature. We report three cases who presented with quadriplegia and vision loss, initially managed as neuromyelitis optica spectrum disorder (NMOSD), based on neuroimaging findings. Two of them initially responded to immune therapy but relapsed after a few months, while one case showed no clinical improvement with immune therapy. The clinical presentation and neuroimaging findings in all three cases were consistent with NMOSD, leading to a delayed diagnosis of BTD. Antiaquaporin4 and antimyelin oligodendrocyte glycoprotein antibodies were negative in all patients. Urine organic acids reported raised markers of biotinidase or holocarboxylase synthase deficiency. Two of them had a dramatic response to biotin supplementation, showing significant improvement in motor function and vision.

L-tyrosine for treatment of an infant with nemaline rod myopathy.

Nemaline rod myopathy is an extremely rare muscle disease responsible for hypotonia and poor muscle strength in infants. The disease has variable phenotypic presentations across different ages, ranging from neonatal to the adult onset and from severe to asymptomatic varieties. Clinical features, muscle biopsy and genetic testing help in diagnosis. The histopathological examination shows the presence of rod-like structures or nemaline bodies in muscles. Management remains mainly supportive, and currently, there is no available curative treatment. This case report describes an infant presenting with gross hypotonia, poor handling of secretions and multiple extubation failures who was diagnosed by clinical exome sequencing. The patient harboured compound heterozygous variants in the NEB gene suggestive of nemaline rod myopathy. The newborn showed significant improvement in muscle strength after he was started on dietary L-tyrosine supplementation. This case highlights the emerging role of L-tyrosine in the supportive care of infants with nemaline rod myopathy.

Non-ketotic hyperglycinaemia masquerading as a hypotonic-hyporesponsive episode following vaccination in an infant.

Non-ketotic hyperglycinaemia (NKH) is an inborn error of glycine metabolism with autosomal recessive inheritance. A female infant presented to our emergency department with intractable seizures, lethargy and hypotonia, 2 weeks after her routine vaccination. Detailed infective and metabolic workup revealed normal blood sugar, ketone, lactate ammonia, and a high level of glycine in serum and cerebrospinal fluid suggesting NKH. Diagnosis of NKH was further confirmed on genetic analysis for AMT gene mutation. The child showed clinical improvement with oral sodium benzoate. Here, we report the inheritance, pathophysiology, diagnostic approach, genetic confirmation, management and prognosis of a child with NKH.

Hemichorea-hemiballismus due to diabetic striatopathy a serious complication of uncontrolled diabetes.

We report the case of a man in his mid-80s with diabetes mellitus who presented to the emergency department with a 1-day history of right-sided choreiform movements and falls. Laboratory tests revealed blood glucose of 597 mg/dL. Non-contrast CT imaging of his head demonstrated a faint hyperdensity involving the left lentiform nucleus and brain MRI showed a hyperintensity in the left basal ganglia on T1-weighted images. These lesions are typical of diabetic striatopathy. Symptoms of hemichorea/hemiballismus did not resolve with glycaemic control and several pharmacological agents were tried with eventual improvement with risperidone. He was discharged to a rehabilitation facility and had mild persistent arm chorea at 6-month follow-up.

Visual loss and encephalopathy in a pregnant patient with hyperemesis gravidarum.

A pregnant woman in her 20s at 17 weeks of gestation, presented with symptoms of painless diminution of vision preceded by 8 weeks history of hyperemesis gravidarum. On examination, she was confused, disoriented and had gait ataxia with complete loss of vision in both eyes. Fundus examination revealed grade 4 disc oedema with superficial retinal haemorrhages. Possibilities kept were cerebral venous sinus thrombosis, neuromyelitis optica spectrum disorder, posterior reversible encephalopathy syndrome and Wernicke's encephalopathy (WE). Thiamine levels were low. MRI brain with MR venography revealed symmetrical areas of hyperintensities in bilateral medial thalami, hypothalamus, mammillary body and area postrema. She was managed as a case of WE with intravenous thiamine with complete clinical and radiological resolution within 2 weeks of treatment. Therefore, we conclude that a high index of suspicion of WE in appropriate clinical settings leading to early treatment can potentially reverse its grave clinical symptoms and complications.

Role of physical therapy intervention in acute disseminated encephalomyelitis.

We reported a case of a school-going child, diagnosed with acute disseminated encephalomyelitis (ADEM) who presented with symptoms such as high fever, acute hemiplegia and ataxia and was referred for physiotherapeutic intervention. This case report aims to document the assessment and management of ADEM from the intensive care unit to the home setting by physical therapy. Also, the child developed ventilator-associated pneumonia and a right lower motor neuron facial injury for which the child was referred to paediatric physical therapy. Since then, continuing for 8 months has helped the child to be independent in all aspects of mobility with no complaints. The child showed improvement in WeeFIM scores and Sunnybrook facial grading after 99 sessions of intensive physical therapy for approximately 83 hours along with the home programme. It has been proven an efficient treatment method along with other medical lines of treatment for neurological impairment associated with ADEM.

Serotonin syndrome presenting as acute dizziness with supine hypertension and orthostatic hypotension.

Serotonin syndrome (SS) is a drug-induced clinical syndrome characterised by a combination of cognitive, neuromuscular and autonomic dysfunctions. The symptoms may include mild non-specific symptoms such as tremors and diarrhoea to coma and sudden death. Herein, we describe a case of SS in which acute dizziness was associated with supine hypertension and orthostatic hypotension. A man in his mid-30s had a 10-month history of anxiety, depression and chronic tension-type headache. He had been on amitriptyline (25 mg daily) and sertraline (50 mg daily). Increment of sertraline (75 mg daily) and amitriptyline (75 mg daily) and the addition of tramadol led to the development of acute severe dizziness. Physical examinations demonstrate supine hypertension and orthostatic hypotension. He also met the diagnostic criteria of SS. The administration of cyproheptadine provided a complete response to dizziness, supine hypertension, orthostatic hypotension and other clinical features of SS.

Toxic optic neuropathy associated with lamotrigine and levetiracetam dual therapy.

We report the case of an early adolescent male on lamotrigine and levetiracetam therapy with a 1-month history of progressive, bilateral, painless visual loss which resolved on cessation of lamotrigine. To our knowledge, we present the first case of lamotrigine and levetiracetam dual therapy associated with toxic optic neuropathy, supported by electrophysiology and optical coherence tomography (OCT) changes. Electrophysiology findings were consistent with retinal ganglion cell dysfunction, with bilateral optic nerve involvement. Macula OCT showed mild retinal ganglion cell loss in all inner quadrants bilaterally. This case highlights the importance of asking patients with epilepsy treated with lamotrigine and levetiracetam about visual problems and considering early dose reduction or cessation of treatment.

Case of tizanidine withdrawal showing hallucination, decorticate posture and tremor, with hypersympathetic vital signs.

Tizanidine, an α2-adrenergic receptor agonist commonly prescribed as a muscle relaxant, has been associated with limited cases of acute intoxication or withdrawal. Here, we present a case of tizanidine withdrawal in a woman in her 40s who presented with an unusual combination of systemic and neurological symptoms. These included hallucinations, decorticate posture, limb and eyelid tremors, along with hypertension, tachycardia and tachypnoea. The diagnosis of tizanidine withdrawal was established by a comprehensive assessment of the patient's medical history and the systematic exclusion of other potential diseases. Our approach to managing the withdrawal symptoms was to initiate symptomatic treatment with a combination of a beta-blocker and a calcium channel blocker. Remarkably, this intervention successfully resolved both vital signs and neurological manifestations by the following day. In conclusion, tizanidine withdrawal is associated with a distinct and diagnostically significant neurological syndrome characterised by hallucinations, decorticate posture, tremors and hypersympathetic vital signs.

Long-term nivolumab treatment possibly associated with aseptic meningitis.

Nivolumab is a programmed death-1 receptor blocker within the family of medications called immune checkpoint inhibitors (ICIs). Although generally well tolerated, cases of immune-related adverse events (irAEs) have been reported. We present a case of a man being treated with nivolumab for renal cell carcinoma who presented to the emergency department with problems of headache, fever and disorientation. After extensive evaluation, a diagnosis of immunotherapy-induced aseptic meningitis was considered more probable than infectious. Due to stable clinical status, no treatment was initiated, and the patient's condition improved spontaneously. The patient was discharged home. To date, only a handful of prior cases of nivolumab-induced meningitis have been reported. Our case demonstrates that irAEs can occur years after the initiation of ICIs. This was a milder presentation of a neurological irAE that resolved spontaneously with watchful waiting, showing that irAEs are likely an evolving spectrum of disease for which clinicians should be aware.

Neuroimaging features of accidental fentanyl overdose in a toddler.

The opioid epidemic has become a significant public health crisis worldwide. With the rise in popularity of fentanyl, opioid overdoses continue to rise at unprecedented rates. Unfortunately, young children have become collateral damage in the face of the opioid epidemic. Accidental exposures and ingestions are the leading cause of opioid overdose in this age group and can result in significant acute complications, long-term sequelae and even death. We present the case of a toddler with accidental fentanyl ingestion who experienced seizures and required intubation for respiratory distress. He was found to have notable diffusion restriction cerebellar changes on MRI and ultimately discharged with normal neurological function. Our case adds to the growing literature of the clinical presentation and neuroimaging features associated with opioid toxicity in young children.

Agony of akathisia: a case of sodium valproate-induced akathisia.

Akathisia is a subjective feeling of restlessness that often results in a compulsion to move. Drug-related causes are the most common aetiologies. It can often be confused with restless legs syndrome (RLS). We describe a case of valproate-induced akathisia that improved with drug cessation. This case reports a rare but treatable adverse effect of sodium valproate and highlights the importance of differentiating akathisia from RLS.

Ceftriaxone-induced encephalopathy in a patient with a normal renal function.

Ceftriaxone-induced encephalopathy is an exceptionally rare adverse effect of this commonly used cephalosporin and is generally observed in patients undergoing haemodialysis or suffering from severe renal failure. We present a case of a fit woman in her mid-80s with a normal renal function who developed severe fluctuating neurological symptoms (aphasia, loss of contact, chorea-like tongue movements) while being treated with ceftriaxone for a urinary tract infection with bacteraemia. The symptoms began on day 4 of treatment and an adverse drug reaction was suspected on day 7, after exhaustive investigations failed to reveal another cause. A complete recovery was observed 3 days after discontinuing ceftriaxone. Our case highlights the need to consider the diagnosis of ceftriaxone encephalopathy, even if the traditional risk factors are lacking. In this article, we also provide a brief overview of the pathophysiology as well as a literature review concerning the subject.

Amantadine withdrawal in a patient with spinocerebellar ataxia.

We report a case of a man with spinocerebellar ataxia (SCA) on high-dose amantadine who was admitted for acute on chronic dysphagia secondary to progression of SCA. Four days after oral medications were held due to patient's dysphagia, he developed fever, tachycardia and mild rigidity in extremities and became obtunded. Despite antibiotics treatment, the vitals and mental status changes persisted for 8 days. When amantadine was resumed, the patient's vital signs and encephalopathy improved within 2 days. This is among the first reports of amantadine withdrawal syndrome (AWS) in a patient without Parkinson's disease. Our case reinforces the importance of careful medication review at admission and consideration of pharmacologic side effects with not only medication initiation but also discontinuation.

Unilateral chorea linked to cavernous haemangioma involving the putamen improved by surgery.

Unilateral chorea movements caused by cavernous haemangioma in the putamen are extremely rare. We report a case with chorea movements linked to cavernous haemangioma, localised to an area including the putamen in which pharmacotherapy was found to be ineffective. Symptoms were, however, improved by resection of the cavernous haemangioma. In cases where chorea movements linked to cavernous haemangioma, involving the putamen, prove intractable with watchful waiting or pharmacotherapy, improvement can be expected with surgical removal of the cavernous haemangioma. It is also possible to reduce the risk of complications through the use of intraoperative navigation and monitoring.

Delayed myelopathy in a child following organic phosphate poisoning.

We report a rare manifestation of delayed organophosphate (OP) poisoning in a male patient in his early childhood. After initially presenting with a cholinergic crisis after OP exposure, the patient returned 3 weeks later with paraparesis and difficulty with bladder control. The results of the MRI of the spine and brain as well as the nerve conduction studies were normal. Myelopathy induced by OP poisoning should be considered in any patient with a history of OP exposure and a presentation of paraparesis. At most recent follow-up, the patient had full bladder control and could walk without assistance. However, he demonstrated circumduction while walking with upper motor neuron signs. Furthermore, he had mild Achilles tendon contractures on both sides. To enable early detection, neurologists and paediatricians should be aware of this uncommon complication of OP poisoning which may influence neurological outcome.

Benign paroxysmal positional vertigo in a young child.

A girl in her early childhood presented to a regional otolaryngology outpatient clinic with classic signs of benign paroxysmal positional vertigo (BPPV). She reported episodic dizziness when rolling in a supine position. She did not convey any other associated audiovestibular symptoms. A bedside Dix-Hallpike test confirmed geotropic rotational nystagmus indicative of lateral canal BPPV. Due to her young age, limited communicative abilities and concerns for more sinister underlying pathology, a complete neurological examination, MRI and pure tone audiometry were performed. After two sessions of Epley's manoeuvre, she was symptom-free. At her 3-month follow-up, the patient denied any recurrent episodes of vertigo.

Myoedema: a forgotten sign in acute colchicine myopathy.

Colchicine myopathy typically presents acutely to subacutely with progressive limb weakness. The patients may not be on high doses of colchicine but almost always have acute kidney injury. Dehydration from colchicine-induced diarrhoea is often a precipitating factor. The concomitant neurotoxicity may produce mild sensory complaints. This combination of acute neurological symptoms preceded by diarrhoea prompts the diagnosis of Guillain-Barre syndrome (GBS). The absence of cranial nerve deficits, raised creatine kinase and myotonic discharges on electromyogram may help in differentiating this condition from GBS. We describe a clinical sign, myoedema - a mounding phenomenon of muscle that is elicited by percussion and resolves when the patient recovers. It aids in the bedside diagnosis of acute colchicine myopathy as well as distinguish it from other more common causes of acute flaccid paralysis. We also discuss the possible mechanism of colchicine toxicity and the mounding phenomenon.