Wat is Erythema Nodosum - Symptomen, Oorzaken en Behandeling

Epidemiology

EN is the most common clinical form of acute nodular hypodermis. It occurs more often in women between 25 and 40 years but can be observed at any age. Compared to men, women are affected three to six times more. It is rare without sex predominance in the pediatric population. Of worldwide ubiquitous distribution, there is, however, an ethnic and geographical difference in the incidences explained by the variation of triggering etiological factors. Familial cases have been reported and are usually caused by an infectious etiology.

Skin biopsy is not usually needed in the typical forms as a diagnosis can be reached from a detailed history and physical examination. Usual features suggestive of EN include acute onset tender nodules on typical locations(most commonly on shins).

Skin biopsy is useless in typical forms. It is indicated in cases of unusual topography, the persistence of nodules several weeks, fistulization or atrophic scarring, and/or livedoid disposition of nodules. It highlights the involvement of interlobular septa by a lymphohistiocytic inflammatory infiltrate, sparing fat lobules and vessels. This aspect is invariable, whatever the etiology.

History and Physical

EN is characterized in a rather stereotyped way, whatever its cause, by the following evolutionary aspects:

Prodromal Phase

Stade Phase

Nodules are small, 3 to 6, sometimes more, bilateral, roughly symmetrical, and spontaneously painful.

The clinical examination allows specifying the characters of the knots: 10 to 40 mm diameter, warm and firm on palpation, which accentuates their painful character, mobile in relation to the deep planes.

The pain of the lesions is exacerbated by orthostatism, which leads the patient to seek the lying position with raised legs spontaneously.

Regressive Phase

Each nodule evolves in ten days, taking blue and yellowish contusiform aspects towards complete disappearance without sequelae.

EN never involves necrosis, ulceration, or scarring. It often evolves in several outbreaks, favored by orthostatism and spreading out, at worst, over 4 to 8 weeks. The succession of outbreaks confers on the eruption of a polymorphic appearance with knots of different ages, featuring the various shades of local biligenia.

Besides the skin lesion, more than 50% of patients will also complain of joint and muscle pain. Sometimes joint swelling and morning stiffness may be present. The swelling may resolve in a few days, but the pain may last for a few months. There is usually no joint destruction, and the synovial fluid is sterile.

Treatment / Management

Extended rest is desirable and may require work stoppage. Analgesics are prescribed on request. Venous compression reduces the pain felt in orthostatism. Steroidal anti-inflammatory drugs, colchicine (1 to 2 mg/day), may be prescribed until symptoms improve. Etiologic treatment is essential in some cases, and antibiotic therapy is needed in case of streptococcal infection or anti-tuberculosis treatment. In the case of Löfgren syndrome, pulmonary radiographic monitoring is recommended because if mediastinal adenopathies disappear in a few months in most patients, sarcoidosis may persist in 10% of cases.[8][9]

Nodular hypodermitis with vascular involvement (periarteritis nodosa and superficial thrombophlebitis) and damage to deep vessels of medium to sometimes large diameter is associated with hypodermic septal or lobular involvement. Nodules can become necrotic. The diagnosis is primarily histological.

Lobular hypodermitis or panniculitis involves lesions that are primarily greasy. The diagnosis is primarily histological, hence the absolute need for biopsy. Several entities have been distinguished. The nodules can liquefy, fistulate, and leave a scar.