Mild hyperphenylalaninemia (hpa) presenting as orthostatic tremor: a case report.

BACKGROUND: Orthostatic tremor (OT) is a type of postural tremor of the lower extremities that has not been described in either phenylketonuria (PKU) or hyperphenylalaninemia (HPA). Because little is known about the clinical features and therapeutic responses of OT in mild HPA, we describe a mild HPA patient who presented with OT as an initial symptom. CASE PRESENTATION: A 22-year-old male was admitted for bilateral leg tremor while standing, with symptom onset eight months prior. One month before admission, the tremor disappeared in the left leg but persisted in the right leg. Electromyography recorded from the right gastrocnemius revealed a 6-8 Hz tremor, which appeared when the patient was standing and disappeared when he was resting or walking. Blood screening showed a phenylalanine/tyrosine ratio of 2.06 and a phenylalanine level of 140 µmol/L. Urine metabolic screening was negative. Whole-exome sequencing confirmed the presence of a compound heterozygous mutation, c.158G > A and c.728G > A, in phenylalanine hydroxylase (PAH) gene. After three months of levodopa/benserazide tablets (250 mg, tid) and a low-phenylalanine diet treatment, the tremor disappeared. CONCLUSIONS: Young-onset mild HPA is a relatively rare autosomal recessive metabolic disease, and slow OT is a rare clinical feature. Metabolic screening and genetic testing are the keys to early diagnosis and treatment. For adolescents and young adults, appropriate medication and long-term dietary therapy remain important treatments. This case expanded the disease spectrum of slow OT.

Serum Metabolic Correlates of the Antibody Response in Subjects Receiving the Inactivated COVID-19 Vaccine.

BACKGROUND: Metabolites are involved in biological process that govern the immune response to infection and vaccination. Knowledge of how metabolites interact with the immune system during immunization with the COVID-19 vaccine is limited. Here, we report that the serum metabolites are correlated with the magnitude of the antibody response in recipients receiving the inactivated COVID-19 vaccine, which provides critical information for studying metabolism regarding the human immune response to vaccination. METHODS: 106 healthy volunteers without history of SARS-CoV-2 infection or vaccination were prospectively enrolled to receive the primary series of two doses of inactivated whole-virion SARS-CoV-2 vaccine. The serum samples were collected 2-4 weeks after the second dose. The magnitude of the anti-RBD antibody was quantified using surrogate virus neutralization tests. The profile of metabolites in serum was identified using untargeted metabolomics analysis. RESULTS: The level of anti-RBD antibody 14-28 days after the second dose was significantly elevated and its interpersonal variability was diverse in a wide range. Thirty-two samples at extremes of the anti-RBD antibody titer were selected to discover the metabolic correlates. Two hundred and fifteen differential metabolites associated with antibody response independent of body mass index were identified. Pregnenolone and sphingolipid metabolism might be involved in the modulation of the human antibody response to the inactivated COVID-19 vaccine. CONCLUSION: We discovered key metabolites as well as those with a related functional significance that might modulate the human immune response to vaccination.

Contrast extravasation after angioplasty for symptomatic stenosis of the middle cerebral artery: A case report.

Contrast extravasation is a common phenomenon in acute ischaemic stroke patients who are treated with endovascular therapy, but it is rarely reported in selective angioplasty of intracranial artery stenosis. In this case we present the treatment and follow-up studies of a patient with severe stenosis in the M1 segment of the middle cerebral artery. We observed extravasation of contrast medium in the brain tissue around the stent after the operation by a computed tomography scan taken immediately, but the patient did not experience any neurological deficits during the operation and the 4-year follow-up. Also the contrast extravasation did not transform into haemorrhage or hyperperfusion.