X-linked dystonia parkinsonism (XDP), also known as Lubag Syndrome or X-linked Dystonia of Panay, is a rare x-linked progressive movement disorder with high penetrance found almost exclusively in males from

Panay Panay is the sixth-largest and fourth-most populous island in the Philippines, with a total land area of and has a total population of 4,542,926 as of 2020 census. Panay comprises 4.4 percent of the entire population of the country. The City o ...

Philippines The Philippines (; fil, Pilipinas, links=no), officially the Republic of the Philippines ( fil, Republika ng Pilipinas, links=no), * bik, Republika kan Filipinas * ceb, Republika sa Pilipinas * cbk, República de Filipinas * hil, Republ ...

. It is characterized by dystonic movements first typically occurring in the 3rd and 4th decade of life. The dystonic movements often either coexist or develop into parkinsonism within 10 years of disease onset.

Symptoms and signs

Symptoms typically present in the 3rd or 4th decade of life, but have been seen as early as the age of 14. It presents with torsion dystonia, particularly when presenting at a younger age, which then progresses to parkinsonism with or without ongoing dystonia. Often the two symptoms coexist. The parkinsonian features of x-linked dystonia parkinsonism include festinating gait,

bradykinesia Hypokinesia is one of the classifications of movement disorders, and refers to decreased bodily movement. Hypokinesia is characterized by a partial or complete loss of muscle movement due to a disruption in the basal ganglia. Hypokinesia is a sym ...

blepharospasm Blepharospasm is any abnormal contraction of the orbicularis oculi muscle. The condition should be distinguished from the more common, and milder, involuntary quivering of an eyelid, known as myokymia, or fasciculation. In most cases, blepharosp ...

, and

postural instability A balance disorder is a disturbance that causes an individual to feel unsteady, for example when standing or walking. It may be accompanied by feelings of giddiness, or wooziness, or having a sensation of movement, spinning, or floating. Equilibr ...

. It often lacks a resting tremor, helping to differentiate it from

Parkinson's disease Parkinson's disease (PD), or simply Parkinson's, is a long-term degenerative disorder of the central nervous system that mainly affects the motor system. The symptoms usually emerge slowly, and as the disease worsens, non-motor symptoms becom ...

Genetics

X-linked dystonia parkinsonism is thought to result from a mutation of the TAF1 (TATA-binding protein-associated factor 1) gene at Xq13.1. It has an X-linked, recessive pattern of inheritance. Genetic analysis suggests that the responsible mutation was introduced into the ethnic groups of

(especially to the

Hiligaynon people The Hiligaynon people (''mga Hiligaynon''), often referred to as Ilonggo people (''mga Ilonggo'') or Panayan people (''mga Panayanon''), are a Visayan ethnic group whose primary language is Hiligaynon, an Austronesian language of the Visayan b ...

) over two millennia ago.

Diagnosis

Treatment

There is no cure for XDP and medical treatment offers only temporary relief. Some authors have reported benzodiazepines and anticholinergic agents in the early stages of the disease. Botulinum toxin injections have been used to relieve focal dystonia. Deep brain stimulation has shown promise in the few cases treated surgically.

Epidemiology

Although all early reported cases occurred in the Philippines, X-linked dystonia parkinsonism has been diagnosed in Japan, US, Canada, and Germany in people of Filipino descent. The prevalence in the Philippines has been estimated at 1/322,000 and as high as 1/4,000 in the province of Capiz's male population. As an x-linked recessive disease, the majority of those affected are males with females generally being asymptomatic carriers. In the largest described series, the mean age of onset was 39.7 years, the mean duration of illness was 16 years, and the mean age of death was 55.6 years.

History

The high concentration of XDP in the Philippines was first documented in the 1970s after the Philippine General Hospital received 5 neurology referrals labelled as "dystonia musculorum deformans". This sparked an epidemiological survey which was published in 1976. Lee et al. described a series of 28 men, 23 of whom were from Panay Island. She found six families that each had more than one male member affected with XDP and found that there was no male to male transmission. There was also a family history of parkinsonism in some of the patients. The name Lubag is based on the term used by Ilongo speaking Filipinos. It describes any movements with torsion.

References

External links

{{Medical resources , ICD10 = G24.1 , ICD9 = , ICDO = , OMIM = 314250 , DiseasesDB = , MedlinePlus = , eMedicineSubj = , eMedicineTopic = , MeSH = , GeneReviewsNBK = , GeneReviewsName = , Orphanet = 53351 Extrapyramidal and movement disorders Rare diseases Dystonia X-linked recessive disorders