Philip A. Hanna

Mouse bioassay versus Western blot assay for botulinurn toxin antibodies Correlation with clinical response

Objective To compare the mouse protection bioassay (MPB) to the Western blot assay (WBA) in detecting antibodies against botulinum toxin A (BTX-A) and to correlate the assay results with clinical responses to BTX-A injections. Methods MPB and WBA assay results were compared in 51 patients (34 nonresponders and 17 responders) who received BTX-A injections, most commonly for cervical dystonia. A subset of patients received a “test” injection into either the right eyebrow (14) or right frontalis (12). Results Twelve patients with antibodies against BTX-A (Ab+) detected by WBA did not demonstrate antibodies (Ab-) by MPB. Conversely, five patients were Ab+ by MPB but Ab— by WBA. Specificity of the MPB was 100% on all three parameters (clinical, eyebrow, and frontalis injections), whereas WBA specificity was only 71% for clinical response but 100% for both eyebrow and frontalis responses. Sensitivities for both assays were low (33 to 53%). Of the 16 patients previously Ab+ by MPB, seven became negative on retesting after a mean interval of 33 months (range, 6 to 93 months). Conclusions The lower specificity of the WBA compared to the MPB suggests that the WBA detects nonblocking antibodies. Eyebrow and frontalis “test” injections correlated well with MPB and WBA results and with clinical responses and may be useful in the evaluation of BTX nonresponders.

Comparison of mouse bioassay and immunoprecipitation assay for botulinum toxin antibodies

OBJECTIVE To compare a recently developed immunoprecipitation assay (IPA) to the mouse protection bioassay (MPB), currently considered the “gold standard”, for detecting antibodies against botulinum toxin A (BTX-A) and to correlate these assay results with clinical responses to BTX-A injections. METHODS MPB and IPA assays were performed on serum samples from 83 patients (38 non-responders, 45 responders) who received BTX-A injections. Six non-responders had serum tested on two separate occasions. Some patients also received a “test” injection into either the right eyebrow (n=29) or right frontalis (n=19). RESULTS All patients antibody positive (Ab+) by MPB were also Ab+ by IPA, whereas an additional 19 patients (17 with reduced or no clinical response) who were MPB Ab− were Ab+, with low titres, by IPA. Two of these 19 patients (non-responders) were initially MPB Ab− but later became MPB Ab+. Similar to previous studies, the sensitivity for the MPB was low; 50% for clinical, 38% for eyebrow, and 30% for frontalis responses whereas the IPA sensitivity was much higher at 84% for clinical (p<0.001), 77% for eyebrow (p=0.111, NS) and 90% for frontalis responses (p<0.02). The IPA specificity was 89% for clinical, 81% for eyebrow, and 89% for frontalis responses, whereas the MPB specificity was 100% for all three response types, which were all non-significant differences. CONCLUSIONS Both assays had high specificity although the sensitivity of the IPA was higher than the MPB. In addition, the IPA seems to display positivity earlier than the MPB, and as such, it may prognosticate future non-responsiveness. Eyebrow and frontalis “test” injections correlated well with clinical and immunological results and are useful in the assessment of BTX non-responders.

Bilineal transmission in Tourette syndrome

Objective: To investigate the frequency and pattern of bilineal transmission in families of patients with Tourette syndrome (TS) compared with normal control subjects. Methods: The study population consisted of two groups: 1) consecutive patients with TS with both parents (51 family sets; 153 individuals), and 2) normal control subjects randomly selected from public schools (20 family sets; 60 individuals). All patients with TS, normal control subjects, and their parents were evaluated for evidence of TS and associated features. Structured interviews and detailed questionnaires designed to assess tics, obsessive-compulsive behavior (OCB), and attention deficit disorder (ADD) were administered to all people in both groups. Results: In addition to tics, 43 (84.3%) patients with TS had ADD, 33 (64.7%) had OCB, and 31 (60.8%) had both ADD and OCB. In 42 (82.4%) of the 51 patients, at least one parent exhibited features of TS; unilineal transmission (only one parent with tics, OCB, or ADD) was present in 29 (56.9%) TS families and an additional 13 (25.5%) TS families manifested evidence of bilineal transmission (both parents affected). More fathers than mothers of patients with TS had tics (31.4% versus 15.7%), whereas more mothers had OCB than did fathers (33.3% versus 15.7%). Features of ADD were equally distributed among fathers (35.3%) and mothers (33.3%) of patients with TS. Eight of 1,142 (0.7%) children in the general school population had some evidence of TS. One of 40 parents of the normal control subjects (2.5%) had symptoms of ADD, but none of the parents of normal control subjects manifested any features of TS or OCB. Conclusions: This study found evidence for bilineal transmission in one fourth of TS families. Features of the TS spectrum were rare in normal control families. Evidence of tics, OCB, and ADD should be investigated in both parents of patients with TS.

Switching from pergolide to pramipexole in patients with Parkinson's disease

Summary.Objective/Background. To compare the safety and efficacy of pramipexole and pergolide in the treatment of mild to moderate Parkinsons disease (PD). In contrast to pergolide, a D1 and D2 dopamine agonist, pramipexole is a nonergoline dopamine agonist with D2 and preferential D3 dopamine receptor activity. This selective activity may result in clinically different effects. No prospective head-to-head comparison studies of pergolide and pramipexole have been reported. Methods. Patients with PD who were maintained on an optimal dose of pergolide were converted to pramipexole, typically over a one-month period. Clinical assessments were performed just prior to conversion and after an optimal dose of pramipexole was achieved. Results. Twenty-five patients were converted from pergolide to pramipexole during the period of July, 1997 to January, 1999. Three patients were lost to follow-up, and one patient died. Of the remaining 21 patients there were 11 men and 10 women, mean age was 67.3 years ± 10.0 (range 51–84). Mean duration of symptoms prior to conversion was 12.5 years ± 3.4 (range 5–19). All patients (except one) were on concomitant carbidopa/levodopa and experienced motor fluctuations. After a mean follow-up of 5.9 ± 2.9 months on pramipexole, the mean levodopa daily dose was reduced from 618.7 mg to 581.2 mg (16.5% reduction, p = 0.61). The mean daily doses of pergolide and pramipexole (in milligrams per day) were 2.1 ± 1.5 (0.15–6) and 3.2 ± 1.1 (0.75–6) respectively. Thirteen patients (62%) reported overall improvement (subjective global response) on pramipexole as compared to pergolide, 5 (24%) were unchanged and 3 (14%) reported worsening. Eighteen of the 21 patients (86%) remained on pramipexole after the study period. Although there was a slight trend toward improved scores on pramipexole, the difference was not statistically significant. Conclusion. This open label study failed to provide evidence of superior efficacy of either dopamine agonist. It is possible, however, that while some patients may benefit more from either pergolide or pramipexole, other patients may obtain additional benefit from other DA agonists or combination therapy. Future randomized, controlled, double-blinded therapeutic trials are needed to determine which, if any, dopamine agonist is superior in the treatment of PD.

A preliminary look at the percentage of patients with Restless Legs Syndrome who also have Parkinson Disease, Essential Tremor or Tourette Syndrome in a single practice

Therapeutic studies, dopamine receptor blocking studies andPositronEmissionTomographic(PET)scanstudiesimplicatethe dopaminergic system in the pathogenesis of the RestlessLegsSyndrome(RLS)(Comella,2002;Eisensehret al.,2001;Michaud et al., 2002; Ruottinen et al., 2000; Staedt et al.,1993;Trenkwalderet al.,1999;Turjanskiet al.,1999;Walterset al.,1991).Itisthereforeofinteresttodeterminewhetherawell-proven dopaminergic disorder, Parkinson Disease (PD),predisposes to RLS, but results of such inquiries have beencontroversial (Krishnan et al., 2003; Ondo et al., 2002; Tanet al.,2002)andnotincompatiblewiththelargeprevalenceofRLSinthegeneralpopulation(Phillipset al.,2000).Therehavebeennopreviousstudieslookingatthereverseprevalence, i.e. the prevalence of PD in RLS. In the currentstudywetakeapreliminarylookatthepercentageofpatientswithRLSwhohavePDinasinglepractice.Tourette Syndrome (TS) is also responsive to eitherdopamineantagonistsoragonistsandRLShasbeenreportedinupto59%ofpatientswithTS(Lipinskiet al.,1997).Thesedata also suggest a dopaminergic hypothesis for RLS. Wethereforelookatthereverseprevalence,i.e.thatofTSinRLSintheaforementionedpractice.PreviousliteraturesuggestsanincreasedprevalenceofRLSin Essential Tremor (ET) (Larner and Allen, 1997) and asubset of patients with ET may be at increased risk for PD(Jankovic,2002).ThisindirectevidencealsosuggeststhatthedopaminesystemmayalsobeinvolvedinRLS.We,thereforealsoagainlookatthereverseprevalenceofETinRLSintheaforementionedpractice.Insummary,basedupontheaforementionedliterature,theproposedaimofthecurrentstudyistotakeapreliminarylookto see if RLS predisposes to other neurologic disordersinvolving the dopaminergic system. We want to emphasizethatthecurrentstudyisnotatrueprevalencestudysinceourpopulationis(a)small,(b)notpopulationbasedand(c)wedonothaveacontrolgroup.All RLS patients currently in the practice of a singleneurologist(ASW)withexpertiseinbothMovementandSleepDisorderswereexaminedforthepresenceofPD,TS,andETatthetimeofreferralforRLS.RLSwasdiagnosedbythefourcriteria established by the International Restless Legs Syn-dromeStudyGroup(Walters,1995).PDwasdiagnosedbythepresenceofbradykinesia,rigidity,restingtremor,andposturalinstability. TS was diagnosed by the presence of motor andvocal tics. ET was diagnosed by the presence of tremor thatwas predominantly a non-intention postural action type andthe absence of any features suggesting PD or cerebellar/spinocerebellardisease.OnlypatientswhowerereferredforRLSwereenteredintothestudy.RLSpatientswereexcludedwhowerereferredforPD,TS,orET.BecauseourdatasuggestedamildincreasedpercentageofPDinRLS,wealsoexcludedtwopatientswhowerereferredforRLSorsleepdisturbance,butwhohadPDatthe time of referral. This was done to exclude the possibilitythatapatientwithbothPDandRLSwouldbemorelikelytobereferredtousthanelsewhere,asweserveasareferralcenterfor both disorders. Patients with atypical parkinsonism werealso excluded. Two patients were also excluded when thediagnosis(PDorET)wasuncertain.Forpurposesofcalculation,thesurveywasconductedatasingle time point in November, 2001. For all three disordersstudied(PD,TS,andET),wecomparedthepercentagesofourRLSpatientswhohadthesedisorderstoprevalencesfromtheliteraturetakingageandsexintoaccount(Table1).Theexactbinomialtestwasusedforcomparison.Tourette’ssyndromeisofjuvenileonsetandtheprevalencerateisfairlystableacrossadultagegroups.Therefore,TSwasdeterminedforall118ofour adult RLS patients of any age in the study (Table1).Because of the tendency for PD to be of later onset andbecause most studies in the literature use an age base of>50years, we confined our survey for PD to our 85 RLSpatients>50yearsofage(Table1).Becauseofthetendencyfor ET to be of later onset and because most studies in theliterature use an age base of >60years, we confined oursurvey for ET to our 56 RLS patients >60years of age(Table1).After exclusion, four (three males, one female) or 4.7% ofour85(47females,38males)RLSpatients>50yearsofagedevelopedPDafterbeingreferredforRLS(Table1).Allhadat least stageII PD at the time of the survey indicating

Restless legs symptoms in a patient with above knee amputations: a case of phantom restless legs.

We describe a 78-year-old gentleman who, following bilateral above-knee amputations, developed symptoms of restless legs syndrome in the absent portions of his lower extremities. These symptoms improved with dopamine agonist therapy. In addition, he later developed parkinsonism with prominent rest tremor on metoclopramide. This suggests that this individual had a dopamine-deficient state which predisposed him to both restless legs syndrome and drug-induced or drug-exacerbated parkinsonism. We propose expanding the spectrum of phantom limb phenomena to include phantom restless legs.

Autosomal dominant hereditary spastic paraplegia with axonal sensory motor polyneuropathy maps to chromosome 21q 22.3

Aim: Hereditary spastic paraplegia (HSP) are a genetically and clinically heterogeneous group of disorders. At present, 19 autosomal dominant loci for HSP have been mapped. We ascertained an American family of European descent segregating an autosomal dominant HSP associated with peripheral neuropathy. Methods: A genome wide scan was performed with 410 microsatellite repeat marker (Weber lab screening set 16) and following linkage and haplotype analysis, fine mapping was performed. Established genes or loci for HSP were excluded by direct sequencing or haplotype analysis. Results: All established loci for HSP were excluded. Fine mapping suggested a locus on chromosome 21q22.3 flanked by markers D21S1411 and D21S1446 with a maximum logarithm of odds score of 2.05 and was supported by haplotype analysis. A number of candidate genes in this region were analyzed and no disease-producing mutations were detected. Conclusion: We present the clinical and genetic analysis of an American family with autosomal dominant HSP with axonal sensory motor polyneuropathy mapping to a novel locus on chromosome 21q22.3 designated SPG56.