Levodopa in drug-induced extrapyramidal disorders

Adequate diagnosis of the cause of Parkinsonism and treatment in an elderly patient with schizophrenia: A case report

Background

Parkinsonism is frequently observed in patients with schizophrenia, and most patients are diagnosed with drug-induced parkinsonism. However, comorbidity with idiopathic Parkinson's disease or Parkinson-plus syndrome is also possible. The pathophysiology and treatment for each of these are entirely different, thus an appropriate diagnosis is required. However, distinguishing them based on clinical symptoms alone is often difficult, and many cases are misdiagnosed. Additionally, Parkinsonism is frequently mistaken for negative symptoms.

Case Description

We report a case of 68-year-old woman diagnosed with schizophrenia, who was admitted to a welfare center. At approximately age 60, the patient experienced motivation reduction, a loss of appetite, and pain in the extremities. In her mid-60s, tremor and muscle rigidity appeared; nuclear medicine testing was performed for a detailed examination, resulting in a diagnosis of levodopa-responsive Parkinson's syndrome. Notably, the patient's parkinsonism and emotional symptoms, which had been considered negative symptoms thus far, improved with levodopa treatment.

Conclusion

This case report illustrates the importance of properly diagnosing the cause of parkinsonism in patients with schizophrenia.

Drug-induced Parkinsonism versus Idiopathic Parkinson Disease: Utility of Nigrosome 1 with 3-T Imaging

Purpose To explore the utility of nigrosome 1 with 3-T magnetic resonance (MR) imaging to differentiate idiopathic Parkinson disease (IPD) from drug-induced parkinsonism (DIP). Materials and Methods The institutional review board approved this study, and participants gave informed consent. This study enrolled patients with DIP (n = 20) and IPD (n = 29) who underwent N-3-fluoropropyl-2-β-carbomethoxy-3-β-(4-iodophenyl)nortropane ((18)F-FP-CIT) positron emission tomography (PET) and healthy participants (n = 20). All participants underwent 0.5 × 0.5 × 1.0 mm(3) oblique axial three-dimensional multiecho-data image combination imaging to view the nigrosome 1 with 3-T imaging. Two reviewers independently assessed the nigrosome 1 without clinical information. DIP was diagnosed when no abnormality was seen at (18)F-FP-CIT PET. Diagnostic sensitivity, specificity, and accuracy of the nigrosome 1 imaging were evaluated between the IPD and DIP patients and between the IPD patients and healthy participants. Interrater agreement was assessed with Cohen κ. Results Both reviewers agreed in 63 of 69 participants (91.3%) for the presence of any abnormality on either side of the nigrosome 1 (κ = 0.825). Findings in all 29 IPD patients (100%) and three of 20 DIP patients (15%) were rated as abnormal and in 17 of 20 DIP patients (85%) they were interpreted as normal on the basis of imaging of the nitgrosome 1 (sensitivity, 100% (29 of 29); specificity, 85.0% (17 of 20); accuracy, 93.9% (46 of 49) between IPD and DIP patients). Findings in 3 of 20 healthy participants (15.0%) were interpreted as abnormal on the basis of imaging the nigrosome 1 while in the other 17 of 20 healthy participants (85.0%) they were rated as normal (sensitivity, 100% [29 of 29]; specificity, 85.0% [17 of 20]; accuracy, 93.9% [46 of 49] between IPD patients and healthy participants [κ = 0.831]). Conclusion The imaging of nigrosome 1 with 3-T imaging can differentiate DIP from IPD with high accuracy and may help to screen patients who need dopamine transporter imaging in those suspected of having DIP. (©) RSNA, 2015 Online supplemental material is available for this article.

[¹²³I]FP-CIT SPECT (DaTSCAN) may be a useful tool to differentiate between Parkinson's disease and vascular or drug-induced parkinsonisms: a meta-analysis

BACKGROUND AND PURPOSE

Differentiating idiopathic Parkinson's disease from secondary parkinsonian syndromes is crucial since their management and prognosis differ considerably. Functional imaging of the dopaminergic pathway by means of [¹²³I]FP-CIT SPECT (DaTSCAN) might be useful in this regard, but its role is still controversial. The accuracy of DaTSCAN in the differential diagnosis between Parkinson's disease and vascular or drug-induced parkinsonism was therefore systematically reviewed.

METHODS

MEDLINE and CENTRAL were searched for studies aiming to determine accuracy measures (sensitivity, specificity, diagnostic odds ratio, positive and negative likelihood ratios) of DaTSCAN in differentiating between Parkinson's disease and vascular or drug-induced parkinsonism.

RESULTS

Five studies were included. Pooled accuracy measures in differentiating between Parkinson's disease and vascular or drug-induced parkinsonism were relatively high, with sensitivity and specificity values above 85% and 80%, respectively.

CONCLUSIONS

DaTSCAN might accurately differentiate between early Parkinson's disease and secondary parkinsonian conditions, namely vascular or drug-induced, in patients with clinically unclear parkinsonism. However, all the studies reviewed here show several methodological limits, which prevent definitive conclusions on the role of DaTSCAN being drawn in this context. Further studies are needed to confirm our results and definitely evaluate the utility of DaTSCAN in differentiating between Parkinson's disease and vascular or drug-induced parkinsonism.

Parkinsonism in patients with chronic hepatitis C treated with interferon-alpha2b: a report of two cases

Details of two patients with chronic hepatitis C infection who developed features of Parkinsonism when treated with IFN-alpha2b and ribavirin are reported. The symptoms resolved when treatment was discontinued in one patient but not in the other. Physicians should be alert to the possibility that drug-related Parkinsonism may complicate treatment of hepatitis C infection with antiviral agents; the agent most likely responsible is IFN-alpha2b. Prompt withdrawal of treatment is mandatory but does not always guarantee reversal of the Parkinsonian features.

DAT imaging in drug-induced and psychogenic parkinsonism

Parkinson's syndrome (PS) is frequently encountered in disorders associated with prominent degeneration of the nigrostriatal pathway as in Parkinson's disease, multisystem atrophy, and progressive supranuclear palsy (presynaptic PS). Drug-induced parkinsonism, a common, underdiagnosed health problem and psychogenic parkinsonism are causes of Parkinson's syndrome which, evidence suggests, occurs without degeneration of nigrostriatal structures. We review clinical features and results of DAT imaging in drug-induced parkinsonism and psychogenic parkinsonism. These two conditions normally give normal striatal DAT imaging results; an abnormal result in either case could exclude both conditions, corroborating a diagnosis of organic parkinsonism in uncertain cases.

A meta-analysis of the response to chronic L-dopa in patients with schizophrenia: therapeutic and heuristic implications

RATIONALE

While it is generally believed that administration of the dopamine precursor levodopa ( L-dopa) exacerbates symptoms of schizophrenia, numerous reports suggest that adjunctive L-dopa may be beneficial. This body of literature has not been critically reviewed.

OBJECTIVES

On the basis of published studies, to determine whether L-dopa administered concomitantly with antipsychotic drugs provides a beneficial response in patients with schizophrenia.

METHODS

This review examined 30 studies involving 716 patients. Due to wide methodological variability and limited statistical information, only five studies encompassing 160 patients could be included in a meta-analysis. The others were evaluated qualitatively.

RESULTS

When L-dopa was added to antipsychotic drugs, the overall improvement was moderate ( d=0.71) and highly significant ( P<0.0001). There were 16 other studies in which L-dopa was added to antipsychotic drugs, but which did not meet criteria for inclusion in the meta-analysis. In these, worsening occurred in less than 20% of patients; the percentage of improved patients varied widely but had a central tendency around 50%.

CONCLUSIONS

. In patients already on antipsychotic drugs, the addition of L-dopa can be beneficial. Dopamine agonists merit further consideration as adjuncts to antipsychotic drugs in the treatment of schizophrenia.

Pyridoxine improves drug-induced parkinsonism and psychosis in a schizophrenic patient

Drug-induced Parkinsonism is a common serious side-effect of neuroleptic therapy. In cases of irreversible drug-induced Parkinsonism, pharmacological management is notoriously difficult. A schizophrenic patient with severe neuroleptic-induced Parkinsonism and Tardive Dyskinesia is presented in whom administration of pyridoxine (vitamin B6) (100 mg/d) resulted in dramatic and persistent attenuation of the movement disorders as well as reduction of psychotic behavior. Since pyridoxine deficiency is associated with marked reduction of cerebral serotonin concentrations and pineal melatonin production in rats, the effects of pyridoxine on the movement disorder and psychosis may have been mediated largely by enhancing serotonin and melatonin functions. An additional effect of excess pyridoxine administration on GABA and dopamine activity cannot be excluded. Pyridoxine has been reported to attenuate the severity of levodopa-induced dyskinesias in patients with Parkinson's disease and it is suggested that pyridoxine supplementation should be considered in psychiatric patients with drug-induced movement disorders including persistent Parkinsonism. An underlying pyridoxine deficiency in these patients may exacerbate the psychotic behavior and additionally, potentially increase the risk of drug-induced movement disorders.

Bromocriptine therapy in chronic schizophrenia: effects on symptomatology, sleep patterns, and prolactin response to stimulation

Ten chronic schizophrenic patients were given bromocriptine in doses increasing from 1.25 to 5 mg over 6 days (the low-dose therapy) and then up to 40 mg over 15 days (the high-dose therapy). Psychopathological status was assessed using the Brief Psychiatric Rating Scale, twice daily the first 6 days, and every 2 days thereafter. The prolactin (PRL) response to haloperidol stimulation (1 mg i.v.) was measured in five cases before and 3 days after the end of high-dose therapy, and in one patient before and 3 days after the end of low-dose therapy. Electroencephalographic sleep studies were carried out before therapy and every 2 nights during low-dose therapy in five patients, and in two cases during high-dose therapy. Bromocriptine therapy modified neither clinical symptomatology nor sleep patterns. The PRL response to haloperidol after therapy was markedly lower than that before therapy in the five patients treated with high doses, and markedly higher in the single patient tested who was treated only with low-dose therapy.

Amphetamine psychosis and schizophrenia: a dual model

Several of the behavioral consequences of acute and chronic amphetamine treatment were evaluated and related to the underlying neurochemical correlates of drug treatment. It was suggested that decreased noradrenergic activity after long-term amphetamine treatment influences stimulus sampling, whereas enhanced dopaminergic activity was responsible for the progressive augmentation of stereotypy and self-stimulation behavior observed after long-term exposure to amphetamine. It was hypothesized that amphetamine-induced psychosis and the symptomatology associated with schizophrenia are related to alterations in both norepinephrine and dopamine activity.

The pathophysiology of extrapyramidal side-effects of neuroleptic drugs

The mechanisms responsible for the production of major extrapyramidal side-effects (parkinsonism, akathisia, acute dystonic reactions, chronic tardive dyskinesias) are reviewed in the light of the complex effects of these drugs on cerebral dopamine systems.

Cerebral hydatid disease in Britain

Two cases of cerebral hydatid disease are described. This condition, acquired by Britons in Britain, is extremely rare as only two similar cases have been reported before. Details of clinical presentation, investigation and treatment are described.