Skeletal Muscle Involvement in Wilson Disease: Clinical and Magnetic Resonance Imaging (MRI) Observations in 2 Families.

OBJECTIVE: Skeletal muscle involvement in Wilson disease is rare. Calf muscle pain might be attributed as growing pain in children. We report calf muscle involvement in Wilson disease and describe the magnetic resonance imaging (MRI) findings of leg, differential diagnosis with literature review. PATIENTS AND METHODS: Our observations describe calf muscle MRI abnormality in 5 cases of Wilson disease from 2 families. The clinical presentations were neurologic in 3, hepatic in 1, and asymptomatic in 1 patient. We systematically describe the clinical characteristics and their calf muscle MRI findings. RESULTS: Three patients had bilateral calf pain and intermittent cramps. The pain was of mild to moderate intensity and managed symptomatically. Serum alkaline phosphatase, creatinine phosphokinase, and needle electromyography were normal. Turbo inversion recovery magnitude sequence MRI of calf muscle revealed hyperintensity in bilateral gastrocnemii muscles. These muscles appear hyperintense in diffusion-weighted imaging. CONCLUSION: The calf muscle involvement could be attributed to muscle edema due to copper-induced muscle toxicity mediated by inhibition of Na+/K+-ATPase on cellular membranes of fast-twitch gastrocnemii muscles which contain predominant type II myofiber. In Wilson disease patients with calf pain or cramps, muscle MRI may show nonspecific gastrocnemius hyperintensity. Further evaluation may give insight into its pathophysiology.

Skull base and calvarial tuberculosis presenting as chronic meningitis.

Calvarial tuberculosis is very rare accounting for 0.2-1.3% of skeletal tuberculosis. Diagnosis is also challenging in these areas due to insidious onset of presentation, low bacterial loads in these sites and unapproachable locations for sample collection. Rarely these patients may presents with features of meningitis when the adjacent meninges are involved. Here we describe a case where tubercular involvement of sphenoid, clivus, and frontal bone, who presented as chronic meningitis and diagnosis was made on the basis of radiological and histopathological findings. All the lesions almost resolved following antitubercular treatment at 5 months follow up. A high index of suspicion is needed for early diagnosis and management of this condition.

Evaluation of the signal quality of wrist-based photoplethysmography.

OBJECTIVE: Wearable devices with embedded photoplethysmography (PPG) sensors enable continuous monitoring of cardiovascular activity, allowing for the detection cardiovascular problems, such as arrhythmias. However, the quality of wrist-based PPG is highly variable, and is subject to artifacts from motion and other interferences. The goal of this paper is to evaluate the signal quality obtained from wrist-based PPG when used in an ambulatory setting. APPROACH: Ambulatory data were collected over a 24 h period for 10 elderly, and 16 non-elderly participants. Visual assessment is used as the gold standard for PPG signal quality, with inter-rater agreement evaluated using Fleiss' Kappa. With this gold standard, 5 classifiers were evaluated using a modified 13-fold cross-validation approach. MAIN RESULTS: A Random Forest quality classification algorithm showed the best performance, with an accuracy of 74.5%, and was then used to evaluate 24 h long ambulatory wrist-based PPG measurements. SIGNIFICANCE: In general, data quality was high at night, and low during the day. Our results suggest wrist-based PPG may be best for continuous cardiovascular monitoring applications during the night, but less useful during the day unless methods can be identified to improve low quality signal segments.