CASE REPORT

A 54-year-old female presented with complaints of a oneyear history of uncomfortable range of motion in all four limbs with stiffness and slowness while moving and walking, and she had no significant history of prior illness or medication. Family history revealed that one of her three siblings experienced a cerebral infarction at the age of 52, and her mother was diagnosed with dementia at the age of 90. On initial examination at age 54, the patient demonstrated hypomimia, mild to moderate bilateral bradykinesia on finger tapping, hand-grasp, and pronation-supination movements of the hands, mild axial and bilateral limb rigidity, mildly stooped posture, and slowing gait with bilaterally reduced arm swing, though no resting or kinetic tremor. Eye movements showed breaking up of smooth pursuit but no supranuclear gaze palsy. Autonomic symptoms and signs were not evident. She did not have depression, sleep problems, or loss of smell. Her Mini-Mental State Examination score was 29/30. The Frontal Assessment Battery score was 15/18, which suggested mild frontal lobe dysfunction. MRI of the brain showed mild diffuse cerebral atrophy. Serum copper and ceruloplasmin tests for Wilson disease were within the normal ranges. A levodopa trial showed subjective minimal improvement. The initial diagnosis was atypical parkinsonian syndrome based on bilateral symmetric parkinsonian features and poor levodopa response. DAT imaging using an (18)F-FP-CIT [(18)F-fluorinated N-3-fluoropropyl-2-beta-carboxymethoxy-3-beta-(4-iodophenyl) nortropane] positron emission tomography scan showed moderately to severely decreased uptake in the putamen bilaterally (Figure 1). At age 56, she developed difficulties raising her head up when lying on her back. Examination showed neck flexion weakness, mild bilateral facial weakness, and percussion and grip myotonia. Needle electromyography confirmed myotonic discharges in proximal and distal muscles. Ophthalmologic examination showed bilateral cataracts. Echocardiography and electrocardiography were normal. A genetic screen for DM type 1 showed an abnormal CTG repeat length with 120 repeats in the untranslated 3' region of DMPK on chromosome 19q13.3. By age 58, the patient had developed gait freezing, postural instability, and frequent falling, as well as progressed to moderate to severe bilateral bradykinesia on finger tapping, hand-grasp, and pronation-supination movements of the hands, moderate to severe axial and bilateral limb rigidity, and moderate stooped posture. Increasing her dose of levodopa to 1,300 mg per day was not effective. She developed dysarthria, dysphasia, and severe weight loss. At age 59, she died from asphyxia. An autopsy was not performed.

DISCUSSION

In this report, the patient was initially diagnosed with atypical parkinsonian syndrome based on bilateral symmetric parkinsonian features and a poor levodopa response. DAT imaging confirmed the presynaptic dopaminergic deficits in the bilateral putamen. Later, she was diagnosed with DM type 1 based on myotonia clinical manifestations and DMPK mutations. To date, there have been no reports of genetically proven cases of DM type 1 with parkinsonism. To our knowledge, this is the first reported case of DM type 1 with DMPK mutations and parkinsonism that developed ahead of muscle symptoms with bilateral putaminal, presynaptic dopaminergic deficits on DAT imaging. The prevalence of DM type 1 appears to be more common than DM type 2, except in Germany, Poland, and Finland, where DM type 2 is as common as DM type 1 [1]. However, parkinsonism has been reported more often in DM type 2 cases than in type 1 cases (Table 1).

Of the previous 5 reported patients with DM who developed parkinsonism (Table 1), an autopsy was performed on 1 patient with clinically diagnosed DM type 1 and parkinsonism [2], who was never genetically tested. The autopsy in the patient showed marked cell loss and Lewy bodies in the substantia nigra (SN) and diffuse myelin loss in the cerebral white matter [2]. However, Lewy bodies in the SN have been reported in other patients with genetically proven or clinically diagnosed DM without parkinsonism [7]. Other neuropathological changes found upon autopsy of genetically proven or clinically diagnosed DM included neurofibrillary tangles, observed mostly in the hippocampus and the temporal neocortex [8]. Marinesco bodies and neuronal loss of the medullary arcuate nucleus and reticular formation were also noted in some cases [9], but were not found consistently, nor were clinicopathological features consistent. Other neuropathological findings included intracytoplasmic inclusion bodies in the thalamus, SN, cerebral cortex, caudate nucleus, and putamen [10], of which the mechanism of pathology remains unknown. Lewy bodies and intracytoplasmic inclusion bodies found in the SN or the subcortical striatum may raise the possibility of association between parkinsonism and DM, but it warrants further studies.

In conclusion, parkinsonism has been reported in patients with DM. The association of parkinsonism and DM may not be coincidental given the current case and other similar reports and their neuropathology results. However, further research is needed to understand the relationship between parkinsonism symptoms and DM.

Notes

Conflicts of Interest

The authors have no financial conflicts of interest.

Acknowledgments

The DNA sample for this study was provided by the Seoul National University Hospital Human Biobank, a member of the National Biobank of Korea, which is supported by the Ministry of Health and Welfare. All samples derived from the National Biobank of Korea were obtained with informed consent under institutional review board-approved protocols.

Figure 1.

FP-CIT positron emission tomography scan showed moderately to severely decreased uptake in the putamen bilaterally.

REFERENCES

• 1. Udd B, Krahe R. The myotonic dystrophies: molecular, clinical, and therapeutic challenges. Lancet Neurol 2012;11:891–905.ArticlePubMed
• 2. Okuma Y, Tanaka S, Nomura Y, Mori H, Yan H, Shirai T, et al. [A 63-year-old woman with muscle weakness, myotonia, and parkinsonism]. No To Shinkei 1996;48:287–297.PubMed
• 3. Hund E, Jansen O, Koch MC, Ricker K, Fogel W, Niedermaier N, et al. Proximal myotonic myopathy with MRI white matter abnormalities of the brain. Neurology 1997;48:33–37.ArticlePubMed
• 4. Chu K, Cho JW, Song EC, Jeon BS. A patient with proximal myotonic myopathy and parkinsonism. Can J Neurol Sci 2002;29:188–190.ArticlePubMed
• 5. Celik Y, Turgut N, Balci K, Kabayel L. Proximal myotonic dystrophy associated with parkinsonism. J Clin Neurosci 2006;13:275–276.ArticlePubMed
• 6. Annic A, Devos D, Destée A, Defebvre L, Lacour A, Hurtevent JF, et al. Early dopasensitive Parkinsonism related to myotonic dystrophy type 2. Mov Disord 2008;23:2100–2101.ArticlePubMed
• 7. Itoh K, Mitani M, Kawamoto K, Futamura N, Funakawa I, Jinnai K, et al. Neuropathology does not correlate with regional differences in the extent of expansion of CTG repeats in the brain with myotonic dystrophy type 1. Acta Histochem Cytochem 2010;43:149–156.ArticlePubMedPMC
• 8. Maurage CA, Udd B, Ruchoux MM, Vermersch P, Kalimo H, Krahe R, et al. Similar brain tau pathology in DM2/PROMM and DM1/Steinert disease. Neurology 2005;65:1636–1638.ArticlePubMed
• 9. Ono S, Takahashi K, Kanda F, Jinnai K, Fukuoka Y, Mitake S, et al. Decrease of neurons in the medullary arcuate nucleus in myotonic dystrophy. Acta Neuropathol 2001;102:89–93.ArticlePubMedPDF
• 10. Ono S, Takahashi K, Fukuoka Y, Jinnai K, Kanda F, Kurisaki H, et al. Intracytoplasmic inclusion bodies of the substantia nigra in myotonic dystrophy. Immunohistochemical observations. J Neurol Sci 1997;148:193–198.ArticlePubMed

Figure & Data

References

Citations

Citations to this article as recorded by  

Comments on this article