The neuropsychiatry of adult-onset adrenoleukodystrophy.

Adrenoleukodystrophy is an inherited X-linked peroxisomal disorder that preferentially affects the adrenal cortex, testes, and brain and may occur at almost any age. Psychiatric symptomatology is present in many of the adult-onset cases reported in the literature and may be one of the earliest manifestations of the disease. The majority of patients with psychiatric disturbances have signs and symptoms typical of mania. Psychosis and cognitive impairment may also be prominent. Metabolic diseases such as adrenoleukodystrophy are probably underrecognized as a cause of psychiatric illness. Increased awareness of these disorders will lead to accurate diagnosis, appropriate treatment selection, and genetic counseling.

Late-onset adrenoleukodystrophy associated with long-standing psychiatric symptoms.

BACKGROUND: It is not commonly appreciated that patients with adrenoleukodystrophy (ALD) can first present in adulthood with psychiatric symptoms. METHOD: This case study involved a 31-year-old man who was referred for a neuropsychiatric assessment of tardive dyskinesia and treatment-resistant psychosis. Upon neurologic examination, he was found to have spasticity, marked hyperreflexia with clonus, and bilateral Babinski signs. T2-weighted magnetic resonance imaging demonstrated severe white matter disease. Metabolic screening revealed abnormalities of very long chain fatty acids consistent with the diagnosis of ALD. These results prompted us to review the literature on late-onset ALD with attention to (1) the nature of the associated psychiatric and neurologic symptoms, (2) the neuroimaging abnormalities associated with this disorder, and (3) treatment considerations. RESULTS: Individuals with adult-onset ALD may initially present with psychiatric symptomatology. Most commonly, these patients manifest signs of mania including disinhibition, impulsivity, increased spending, hypersexuality, loudness, and perseveration. ALD patients will often have upper motor neuron findings on neurologic examination. Despite the name of the disease, patients with ALD may not have clinical evidence of adrenal dysfunction. Neuroimaging reveals diffuse, confluent white matter lesions that typically originate in the parieto-occipital region. Both neuroleptic and anticholinergic medications may result in significant side effects with little resolution of the underlying psychiatric symptoms. CONCLUSION: This case study and review of the literature illustrate the importance of performing neurologic and radiological examinations on all psychiatric patients with chronic illnesses. We emphasize the importance of reexamining and reimaging patients who are not responding to standard treatment. The clinical problem of "treatment resistance" should be seen as an indication that other diagnoses, such as an underlying metabolic disorder, need to be considered.

Improving preventive practice. An educational intervention using chart audit.

OBJECTIVE: To assess if the impact of teaching preventive medicine can be increased by supplementing conventional teaching with a practice based preventive audit undertaken by general practice registrars and their supervisors. METHOD: A practice based medical record audit of preventive activities was undertaken by 30 general practice registrars and 27 of their supervisors. Items recorded were based on the RACGP's Guidelines for Preventive Activities in General Practice. Participants were also asked to identify or target areas identified by the audit which they specifically wished to improve. Following an educational program on preventive medicine for both groups, the audit was repeated to assess changes made. RESULTS: Both registrars and supervisors increased their level of prevention in most parameters measured. Registrars' scores were lower than supervisors' for all items in the initial audit but they made greater improvements by the repeat audit (p < 0.02 for all items). There was great variability between the level of recording of preventive data--from rubella immunity (which was recorded in only 22% of cases) to blood pressure (which was recorded in 94% of cases). There was also variability between practices. Items specifically targeted for improvement by participants did not improve more than other items. CONCLUSION: Supplementing conventional teaching with a practice-based audit improved the level of preventive medicine undertaken in teaching practices, by both registrars and supervisors.

Persistent loss of tyrosine hydroxylase immunoreactivity in the substantia nigra after neuroleptic withdrawal.

A 37 year woman developed neuroleptic induced parkinsonism that persisted long after the drug had been discontinued. This prompted a study of the effect of an eight week course of haloperidol (HAL) followed by two week withdrawal, on dopaminergic neurons of the substantia nigra in rats. Animals treated with HAL showed a highly significant 32%-46% loss of tyrosine hydroxylase (TH) immunoreactive neurons in the substantia nigra, and 20% contraction of the TH stained dendritic arbour. Neuroleptic drug induced downregulation of nigral dopaminergic neurons may help to explain the persistent parkinsonism found in many patients after withdrawal of medication.

Haloperidol induces persistent down-regulation of tyrosine hydroxylase immunoreactivity in substantia nigra but not ventral tegmental area in the rat.

The dopamine antagonist haloperidol can cause tardive side-effects that may persist after the drug is withdrawn. We studied the time course of changes in dopaminergic neurons of the substantia nigra and ventral tegmental area following withdrawal of haloperidol. Rats received daily intraperitoneal injections of saline or haloperidol for eight weeks and were killed at two, four or 12 weeks after the final injection. Sections of substantia nigra and ventral tegmental area were processed for tyrosine hydroxylase immunohistochemistry. Quantitative morphometric analysis was carried out blinded in order to determine the number, cell body size and topography of tyrosine hydroxylase-positive cells, and the immunoreactive area of the substantia nigra and ventral tegmental area. In haloperidol-treated rats, tyrosine hydroxylase-positive cell counts were normal in ventral tegmental area but were decreased in substantia nigra by 34% at two weeks withdrawal and by 52% at four weeks withdrawal; cell counts were almost fully recovered by 12 weeks withdrawal. Cross-sectional area of tyrosine hydroxylase immunoreactivity within the substantia nigra demonstrated a similar pattern of reduction, with full recovery by 12 weeks withdrawal. Mean cell size, by contrast, was essentially unchanged at two and four weeks withdrawal, but was significantly decreased in sub-regions of substantia nigra at 12 weeks withdrawal. These results indicate that haloperidol can produce selective changes in midbrain dopamine neurons that persist long after discontinuation of the drug. This decrease in tyrosine hydroxylase-immunoreactive cell counts may play a role in the neurobiology of the persistent tardive syndromes associated with the use of neuroleptics.

Role of glutamate receptor subtypes in the differential release of somatostatin, neuropeptide Y, and substance P in primary serum-free cultures of striatal neurons.

The spiny and aspiny neuronal populations of the striatum display differential vulnerability to the toxic effects of glutamatergic agonists. Substance P-containing spiny neurons appear to be more vulnerable to NMDA-receptor-mediated toxicity and less susceptible to kainate toxicity than the somatostatin- and neuropeptide Y (NPY)-containing aspiny population. We studied whether selective glutamatergic agonists might have similar differential effects on neuropeptide release from the substance P- and somatostatin/NPY-containing neuronal populations. After collection of a baseline sample, striatal neurons in primary culture were treated with one of the following: phosphate-buffered saline, 56 mM potassium chloride (KCl), 100 microM N-methyl-D-aspartate (NMDA), 100 microM quisqualate, 100 microM kainate, or 100 microM glutamate. Baseline and treatment samples were measured by radioimmunoassay for somatostatin, NPY, and substance P. KCl and kainate provoked a selective release of somatostatin and NPY, whereas substance P measured in the same samples showed no response. By contrast, NMDA elicited a selective release of substance P without a similar increase of either somatostatin or NPY. Quisqualate evoked comparable responses in the three peptides. These results indicate that the glutamatergic regulation of somatostatin and NPY release from aspiny striatal neurons in primary culture is preferentially mediated by the kainate receptor, whereas substance P release is selectively mediated by the NMDA receptor. These findings suggest a preferential expression of functional kainate receptors on the aspiny somatostatin/NPY neurons and of NMDA receptors on the substance-P-containing spiny neurons.

The ontogeny of NADPH-diaphorase neurons in serum-free striatal cultures parallels in vivo development.

Nitric oxide synthase is co-localized with somatostatin and neuropeptide Y in a subpopulation of striatal interneurons that stain selectively for NADPH-diaphorase. We studied the ontogeny of diaphorase-positive neurons in striatal serum-free cultures derived from 15-16-day-old CD1 mice. NADPH-diaphorase staining was detected as early as embryological day 18 in vivo and day 5 in vitro. Over the next seven days the number of neurons staining for NADPH-diaphorase increased rapidly and then levelled off at about 0.5-1% of the total neuronal population both in vivo and in vitro. The cultured diaphorase neurons were also similar to their in vivo counterparts in terms of morphology and dendritic branching. Striatal neurons expressing NADPH-diaphorase exhibit similar ontogeny, morphology and neurochemical characteristics in vivo and in serum-free primary neuronal cultures. The culture system may represent a useful model for studying this important subgroup of striatal neurons.

Cortical peptide changes in Huntington's disease may be independent of striatal degeneration.

Patients with Huntington's disease (HD) develop pathological changes in cerebral cortex as well as in striatum. We studied levels of neuropeptide immunoreactivity in 13 areas of postmortem cerebral cortex dissected from 24 cases of HD and 12 controls. Concentrations of immunoreactive cholecystokinin (CCK-LI) were consistently elevated 57 to 153% in HD cortex. Levels of vasoactive intestinal polypeptide (VIP-LI) and neuropeptide Y (NPY-LI) were significantly increased in 10 and 8 of the 13 cortical regions, respectively. Concentrations of somatostatin (SRIF-LI) were increased in only 3 areas, while substance P (SP-LI) was, for the most part, unchanged. Detailed analyses of the CCK-LI and VIP-LI data showed there to be no relationship between the increased cortical peptide levels and the degree of striatal atrophy. We studied the same cortical peptides in rats with long-standing striatal lesions and found no significant changes of CCK-LI, NPY-LI, VIP-LI, or SRIF-LI in any of the 8 cortical regions that were examined. These results indicate that there are widespread and differential changes in cortical neuropeptide systems in HD and that these changes occur independently of the striatal pathology that characterizes the illness.

The ontogeny of NADPH-diaphorase neurons in serum-free striatal cultures parallels in vivo development.

Nitric oxide synthase is co-localized with somatostatin and neuropeptide Y in a subpopulation of striatal interneurons that stain selectively for NADPH-diaphorase. We studied the ontogeny of diaphorase-positive neurons in striatal serum-free cultures derived from 15-16-day-old CD1 mice. NADPH-diaphorase staining was detected as early as embryological day 18 in vivo and day 5 in vitro. Over the next seven days the number of neurons staining for NADPH-diaphorase increased rapidly and then levelled off at about 0.5-1% of the total neuronal population both in vivo and in vitro. The cultured diaphorase neurons were also similar to their in vivo counterparts in terms of morphology and dendritic branching. Striatal neurons expressing NADPH-diaphorase exhibit similar ontogeny, morphology and neurochemical characteristics in vivo and in serum-free primary neuronal cultures. The culture system may represent a useful model for studying this important subgroup of striatal neurons.

Dopamine-glutamate interactions in the striatum: behaviourally relevant modification of excitotoxicity by dopamine receptor-mediated mechanisms.

The two most important afferent projections to the striatum contain glutamate and dopamine, respectively. Excitotoxic damage resulting from excessive stimulation of the N-methyl-D-aspartate subtype of glutamate receptor has been implicated in pathophysiology of ischaemic stroke, hypoglycaemic brain damage and Huntington's disease. We studied the ability of the dopamine system to modify the anatomical, neurochemical and behavioural consequences of glutamatergic toxicity in the striatum. In a first set of experiments, the specific N-methyl-D-aspartate receptor agonist quinolinate was injected unilaterally into the striatum of rats pretreated with one of (i) intraperitoneal (i.p.) saline (controls); (ii) i.p. haloperidol, a D2 dopamine receptor agonist; or (iii) 6-hydroxydopamine lesion of the ipsilateral nigrostriatal tract. Quinolinate-induced striatal damage, as assessed by morphometric and neurochemical criteria, was significantly attenuated in the animals with 6-hydroxydopamine lesions and in those pretreated with haloperidol, compared with saline-pretreated controls. There were no significant differences between the 6-OHDA and haloperidol groups. In a second set of experiments, animals received (i) bilateral intrastriatal quinolinate plus perioperative i.p. saline; (ii) bilateral intrastriatal quinolinate plus i.p. haloperidol; or (iii) bilateral intrastriatal saline. Again, the quinolinate-lesioned animals treated with perioperative haloperidol had significantly less striatal damage than the bilateral quinolinate rats. Behavioural assessment in the Morris Water Maze showed the bilateral quinolinate+haloperidol group to be significantly less impaired on a spatial acquisition task than the bilateral quinolinate animals. Measures of spontaneous daytime motor activity showed significant differences in average speed and rest time between the bilateral quinolinate+haloperidol rats and the bilateral quinolinate group. The performance of the bilateral quinolinate+haloperidol group was not significantly different from that of controls on any of the behavioural tasks. These results indicate an important role for D2 dopamine receptor-mediated mechanisms in striatal excitotoxicity. Since the excitotoxic process involves the same fundamental signalling mechanism that is involved in normal glutamatergic transmission, these findings imply an ability of D2 receptor blockade to modify glutamate signalling in the striatum. These results may have implications for treatment strategies in ischaemic stroke, hypoglycaemic brain damage and schizophrenia.

Spinal stenosis. Results of treatment.

Seventy patients with spinal stenosis are reported according to the new international classifications. Cases where the stenosis was caused mainly by interluminar lesions such as disk protrusion are excluded. The treatment of patients with segmental disease and adequate technical decompression was generally successful while the patients with more generalized disease had less predictable end results. In spite of wide decompression of the lateral gutter of the spinal canal, there was little tendency to further olisthesis except in the degenerative spondylolisthesis group. Spinal fusion did not appear to be necessary except in this latter group of patients. Technetium polyphosphate scanning techniques have shown an active process in the facet joints of the spondylolisthesis group with degenerative disease.