Non-physiological, excessive dopaminergic stimulation can cause dyskinesia-hyperpyrexia syndrome (DHS), which was initially reported by Gil-Navarro and Grandas in 2010. A 70-years-old woman with a 13-years history of Parkinson's disease (PD) was hospitalized due to difficulty walking, despite being treated with levodopa/carbidopa (600 mg/day), immediate-release pramipexole (3 mg/day), and selegiline (5 mg/day). Immediate-release pramipexole was changed to extended-release pramipexole without changing the dose or levodopa equivalent dose (LED). The patient's adherence to drugs was good. The parkinsonism gradually improved and the patient was discharged. One month later, the patient developed severe generalized athetotic dyskinesia with visual hallucinations and hyperpyrexia that lasted for a week, and she was readmitted to hospital. On admission, the patient was conscious but slightly disoriented. Body temperature was 40.3°C with hyperhidrosis. Leukocyte count in the peripheral blood was 1.78×10(4)/ml and serum creatine kinase was >3×10(4) U/l. Chest survey, whole-body computed tomography, and cranial magnetic resonance imaging showed no abnormalities. The patient was diagnosed with DHS and treated by tapering the oral administration of dopaminergic drugs, including extended-release pramipexole. Her clinical condition recovered without dyskinesia, and serum creatine kinase level swiftly normalized. DHS and resemblant conditions are reported to occur in long-term PD patients with motor complications. In advanced stage PD, loss of dopaminergic neurons impairs the dopamine holding capacity of the striatum and exogenous dopaminergic drugs can result in uncontrollable and excessive fluctuations in dopamine concentration. Our case recommends caution when switching to long-acting dopaminergic drugs, even if the dose is unchanged, could lead to excessive dopaminergic stimulation. This case highlights the importance of considering both the LED and the duration of action of dopaminergic drugs when adjusting medication.

Little is known about the relationship between regional cerebral blood flow (rCBF) change and clinical improvement in patients with Parkinson’s disease (PD). Single-photon emission computed tomography (SPECT) measurement of cerebral blood flow allows evaluation of temporal changes in brain function, and using SPECT, we aimed to identify motor improvement-related rCBF changes in response to the administration of antiparkinsonian drugs. Thirty PD patients (16 without dementia; 14 with dementia) were scanned with technetium-99m labeled ethyl cysteinate dimer SPECT and were rated with the Movement Disorder Society-Unified Parkinson’s Disease Rating Scale part III, both before and after a single administration of antiparkinsonian drugs. The SPECT data were processed using Statistical Parametric Mapping 2, the easy Z-score Imaging System, and voxel-based Stereotactic Extraction Estimation. The rCBF responses in the deep brain structures after administration of antiparkinsonian drugs tended to be larger than those in cortical areas. Among these deep brain structures, the rCBF increases in the substantia nigra (SN), lateral geniculate (LG) body, and medial geniculate (MG) body correlated with drug efficacy (p<0.05, respectively). A subgroup analysis revealed that the motor improvement-related rCBF change in the MG was statistically significant, irrespective of cognitive function, but the significant changes in the LG and SN were not found in subjects with dementia. In conclusion, our SPECT study clearly exhibited drug-driven rCBF changes in PD patients, and we newly identified motor improvement-related rCBF changes in the LG and MG. These results suggest that rCBF changes in these regions could be considered as candidates for clinical indicators for objective evaluation of disease progression. Furthermore, functional studies focusing on the LG and MG, especially in relation to therapies using audio-visual stimuli, may bring some new clues to explain the pathophysiology of PD.

Objective To clarify whether antiparkinsonian drugs contribute to nocturnal sleep disturbances in patients with Parkinson’s disease (PD). Background Although the major antiparkinsonian drugs L-dopa and dopamine agonists (DAs) have been found to affect sleep, little is known about the effects of specific drugs on sleep in PD patients. Methods The study participants consisted of 112 PD patients (median age 72.5 years [inter-quartile range: IQR 65–79]; mean disease duration 8.44 years [standard deviation: 7.33]; median Hoehn and Yahr stage 3 [IQR 2–3.75]) taking one of three types of non-ergot extended-release DAs (rotigotine 32; pramipexole 44; ropinirole 36) with or without L-dopa (median daily total dosage of antiparkinsonian drugs 525.5 mg [IQR 376.25–658] levodopa equivalent dose [LED]). Participants were assessed using the PD Sleep Scale-2 (PDSS-2). Results For the whole PD patient cohort, the PDSS-2 sleep disturbance domain score and the scores for item 1 assessing sleep quality and item 8 assessing nocturia were positively correlated with daily total dosage of antiparkinsonian drugs and dosage of L-dopa, but not with the dosage of DAs. Sub-analysis according to DA treatment revealed that DA dosage was not correlated with item 1 or 8 score in any of the subgroups. The LED ratio of rotigotine to the total dosage of antiparkinsonian drugs was inversely correlated with the item 1 score. Conclusions These data suggest that antiparkinsonian drugs, in particular L-dopa, adversely affect nocturnal sleep in PD patients, especially in terms of sleep quality and nocturia. Thus, adjusting both the total dosage of antiparkinsonian drugs and the dose-ratio of L-dopa might be key actions for alleviating poor sleep quality in patients with PD. Among DAs, we found a clear positive correlation between the dose-ratio of rotigotine and sleep quality. Thus, partial L-dopa replacement with rotigotine could improve sleep quality in patients with PD.

A 45-year-old man presented with fever, progressive mutism and memory loss, was admitted to our hospital. MR imaging and angiography suggested multiple foci of infarctions and vasculitis without Gadrinium-enhancement. CSF examination revealed pleocytosis with mononuclear cell dominance and elevated protein content. Adenosine deaminase activity was accelerated, and no malignant cell was found. Whole body CT imaging and Garium-scintigraphy were normal. Under the clinical diagnosis of tuberculous meningitis, anti-tubercular drugs with steroid were administered, resulting in marked attenuation of his neurological impairments. Four months later, his symptoms aggravated and restudy of Garium-scintigraphy revealed enhanced accumulation in the submandibular and abdominal lymphnodes. A lymph node biopsy revealed diffuse large B-cell lymphoma cells. In such a case of this clinical statue, careful and repeated observations should be required to establish the correct diagnosis of occult lymphoma.