Dermatomyositis
| Classification according to ICD-10 | |
|---|---|
| M33.0 | Juvenile dermatomyositis |
| M33.1 | Other dermatomyositis |
| ICD-10 online (WHO version 2019) | |
The dermatomyositis ( DM , even Lila disease , Wagner Unverricht syndrome) is an idiopathic myopathy (muscle disease) or myositis (muscle inflammation) with skin involvement and belongs to the group of collagen . If only the muscles are affected, it is usually referred to as polymyositis (PM). Current studies on the pathogenesis of DM and PM contradict one another. Since it has not yet been established whether DM and PM have the same pathogenesis, dermatomyositis is discussed separately below and polymyositis is only referred to.
The disease is rare and can occur at any age. The maximum frequency is the age of 50, women are affected more often than men ( gynecotropy 2: 1). The maximum age for children is four to twelve years. In domestic dogs , dermatomyositis occurs almost exclusively in puppies and young dogs.
It was described by Ernst Leberecht Wagner (1821–1888) in 1863 and further examined by Heinrich Unverricht .
Human dermatomyositis
Paraneoplastic dermatomyositis
About 50% of dermatomyositides are associated with tumors . Ovarian carcinoma deserves special mention . It is therefore necessary to look for tumors in newly developed dermatomyositis. However, the temporal relationship between the occurrence of dermatomyositis and that of the tumor is extremely variable - the skin and muscle disease can both precede and follow the tumor or manifest at the same time. In some cases, the recurrence of dermatomyositis after a tumor has healed in the meantime can cause its recurrence, i. H. Return, show. The dermatomyositis that occurs as part of a neoplasm is completely reversible after the neoplasm has been removed.
Juvenile dermatomyositis
Juvenile DM is a multisystemic disease with muscle weakness (mostly proximal ) and pain as well as typical skin changes.
A cause is not yet known, but it is suspected that viruses trigger autoimmunization (especially Coxsackie viruses are suspected), which sometimes leads to vasculitis .
clinic
- Muscle weakness (always symmetrical and mainly proximal, i.e. with shoulder and pelvic muscles), muscle pain
- Skin changes:
- Efflorescences : purple-colored edematous erythema , especially on the lids, on the face ( butterfly erythema ) and on the trunk.
- Swelling and redness, as well as later skin atrophy, can be found on the extensor joints of the finger ("Gottron papules")
- Telangiectasia on the fingernails
- Vasculitis: Vasculitis can lead to ulcers of the intestine and thus to perforation .
- Organ involvement of the heart ( perimyocarditis ), lungs ( pneumonia ), liver ( enlargement ), spleen ( enlargement ) and the central nervous system are possible.
diagnosis
The diagnosis is made based on the clinical features described above. Additional evidence for DM are increased muscle enzymes ( creatine kinase ), transaminases and LDH . A muscle biopsy is only necessary in exceptional cases. In electromyogram often leaves a myositis evidence.
therapy
The therapy consists in immunosuppression by
- Corticosteroids (for example, prednisolone)
- Cytostatics (for example methotrexate)
- Immunosuppressants (e.g. ciclosporin)
In severe cases, a combination of the last two can be chosen (e.g. methotrexate and ciclosporin) as well as early physiotherapy .
Dermatomyositis in Dogs
In domestic dogs , dermatomyositis occurs almost exclusively in puppies and young dogs ( juvenile dermatomyositis ). Mainly affected breeds are Collie , with a milder course also Sheltie and Australian Shepherd . A genetic defect that leads to an autoimmune disease is suspected as a possible cause due to the racial predisposition and, within this, also a familial accumulation . The combination of the genetic defect with viruses is also discussed.
clinic
The disease usually begins after weaning at 7 to 11 weeks of age. In mild forms, the early symptoms are often overlooked, so that the disease is only noticed at three to six months.
Dermatomyositis manifests itself in the form of reddening of the skin , dandruff, hair loss, vesicles, pustules and crusts, as well as non-painful ulcers . These occur mainly on the face, on the tip of the tail and on the limbs in the area of protruding bones. The lesions usually heal with scarring by the 8th month of life. The muscle symptoms usually only appear in the late stage, one to two months after the skin symptoms. Muscle weakness and atrophy occur, with the masticatory muscles being particularly affected, so that food intake is severely hindered and salivation can occur. A megaesophagus with regurgitation can also occur.
Lupus erythematosus , polymyositis and leishmaniasis must be excluded from the differential diagnosis . Also demodicosis , dermatophytosis , pyoderma and ischemic vasculopathy can cause similar symptoms. The diagnosis can be confirmed with a histological examination of a biopsy and electromyography .
While milder forms of dermatomyositis heal by themselves, treatment with pentofylline can be used for moderate forms . In addition, protection from sunlight, the administration of unsaturated fatty acids and vitamin E and the avoidance of physical activity with excessive stress on the skin can be used as support. Severe forms can be tackled with a combination of prednisolone and azathioprine , but the prognosis is worse, especially if there is pronounced muscle wasting. Trauma and sunlight should be avoided. Exclusion from breeding is recommended because of the familial accumulation.
literature
- Human dermatomyositis
- S1 guideline juvenile dermatomyositis of the German Society for Child and Adolescent Medicine (DGKJ). In: AWMF online (as of 2013)
- Dermatomyositis of the Dog
- Chiara Noli and F. Scarampella: Dermatomyositis . In: Practical Dermatology in Dogs and Cats . 2nd Edition. Schlütersche, Hannover 2005, ISBN 3-87706-713-1 , p. 321-323 .
Web links
Individual evidence
- ↑ Morris DO: Ischemic dermatopathies. In: Vet Clin North Am Small Anim Pract. 2013; 43 (1): 99-111.
