PRACTICAL NEUROLOGY最新文献

HyperCKaemia is common in several myopathies but can accompany other disorders, including neuropathies. However, distinguishing neurogenic from myopathic hyperCKaemia is not always straightforward. A 58-year-old man had experienced muscle cramps and fatiguability since aged 3 years, with persistently high serum creatine kinase (CK). A positive family history prompted genetic testing for Charcot-Marie-Tooth disease type 1A, which was positive. However, his serum CK remained persistently high and neurological examination 17 years later identified diffuse muscle atrophy and weakness. Genetic testing for dystrophinopathy identified a novel missense variant on the DMD gene. Patients whose serum CK is in 'myopathic range', even those with definite neurogenic disease, should be investigated for additional myopathy, since this may require additional monitoring for pulmonary and cardiac complications.

A 38-year-old man developed headache, dysarthria and dysphasia after insufflation of cocaine. Brain imaging showed multiple white matter lesions, suggesting acute disseminated encephalomyelitis (ADEM), but the clinical features were atypical for demyelination. These lesions may represent a levamisole-associated vascular endotheliopathy, with a mechanism similar to posterior reversible encephalopathy syndrome. Levamisole is a no longer used chemotherapeutic agent but is a legally acquirable veterinary antihelminthic and is often used to adulterate cocaine. Given the rise in cocaine-related hospitalisations, this case raises awareness of an important ADEM mimic.

Sweet's syndrome is an autoinflammatory disease characterised by systemic symptoms and a cutaneous neutrophilic dermatosis. Neurological involvement is rare but important to recognise. Patients may have headache, confusion, seizures, and focal neurological deficits; MR brain scanning may show widespread T2-hyperintense lesions, with a CSF pleocytosis. Clinicians should suspect neurological Sweet's syndrome in patients with central nervous system dysfunction, who have unexplained fever or systemic inflammation, and a pustular neutrophilic dermatosis. The condition responds well to corticosteroids, which can prevent long-term neurological sequalae.

Somatosensory evoked potentials (SSEPs) are electrical potentials that measure various parts of the ascending somatosensory pathways. They are elicited through stimulating mixed nerves, with subsequent orthodromic stimulation of sensory nerves. Despite advances in imaging, SSEPs complement both the clinical examination and peripheral neurophysiological studies when assessing the functional integrity of the sensory pathways, being especially helpful when imaging is inconclusive. We describe the technique of performing SSEPs and the anatomical substrates of their waveforms, and we highlight important clinical applications both in central and peripheral nervous system disorders.

Immune checkpoint inhibition unleashes the power of the immune system against tumour cells. Immune checkpoint inhibitors (ICIs) block the inhibitory effects of cytotoxic T-lymphocyte associated protein 4, programmed death protein 1, programmed death ligand 1 and lymphocyte activation gene 3 molecules on T-cells, and so enhance physiological cytotoxic effects. ICIs can significantly improve survival from cancers, including those previously associated with poor treatment response, such as metastatic melanoma. However, on-target off-tumour effects of ICIs result in immune-related adverse events. These toxicities are common and require new multidisciplinary expertise to manage. ICI neurotoxicity is relatively rare but ominous due to its severity, heterogenous manifestations and potential for long-term disability. Neurotoxic syndromes are novel and often present precipitously. Here, we describe ICI mechanisms of action, their impact on cancer outcomes and their frequency of immune-related adverse events. We focus particularly on neurotoxicity. We discuss the current appreciation of neurotoxic syndromes, management strategies and outcomes based on clinical expertise and consensus, multi-specialty guidance. The use of immunotherapy is expanding exponentially across multiple cancer types and so too will our approach to these cases.