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|Classification and external resources|
|Classification and external resources|
Adiposis dolorosa, also known as Dercum's disease, is a rare condition characterized by multiple, painful lipomas. These lipomas mainly occur on the trunk, the upper arms and upper legs. The understanding of the cause and mechanism of Dercum disease remains unknown. Possible etiologies include: nervous system dysfunction, mechanical pressure on nerves, adipose tissue dysfunction and trauma.
Dercum’s disease most commonly appears between the ages of 35 and 50 years of age. It is five to thirty times more common in women than in men. Originally, Dercum proposed that the condition mainly affects postmenopausal women. However, a 2007 survey has revealed that 85.7 percent of the included patients developed Dercum’s disease before menopause. The prevalence of Dercum’s disease has not yet been exactly established.
Four cardinal symptoms have sometimes been used as diagnostic criteria. 1) painful, fatty lipomas (benign fatty tumors) across anatomy; 2) obesity, frequently in menopausal age; 3) weakness and fatigue; 4) emotional instability, depression, epilepsy, confusion, and dementia. However, as it is unclear which symptoms are cardinal and which symptoms are minor signs in Dercum’s disease, it is unclear which should be used as diagnostic criteria. Researchers have proposed a 'minimal definition' based on symptoms most often part of Dercum's disease: 1) Generalized overweight or obesity. 2) Chronic pain in the adipose tissue. The associated symptoms in Dercum’s disease include obesity, fatty deposits, easy bruisability, sleep disturbances, impaired memory, depression, difficulty concentrating, anxiety, rapid heartbeat, shortness of breath, diabetes, bloating, constipation, fatigue, weakness and joint and muscle aches. Regarding the associated symptoms in Dercum’s disease, only case reports have been published. No study involving medical examinations has been performed in a large group of patients.
The etiology of the disease is unknown. Proposed, but unconfirmed etiologies include: nervous system dysfunction, mechanical pressure on nerves, adipose tissue dysfunction and trauma.
A diagnosis of Dercum's disease is based on patient history and the physical findings. There are no specific laboratory test for this disease. Ultrasound and Magnetic Resonance Imaging can play a role in diagnosis.
Few convincing large studies on the treatment of Dercum’s disease have been conducted. Most of the different treatment strategies that exist are based on case reports. Treatment of Dercum's disease is usually targeted towards pain relief rather than lipoma removal. Currently, there is a lack of scientific data on the use of integrative therapies for the treatment or prevention of Dercum's disease. Not enough studies have been done to prove that diet and supplements could help with the disease.
Treatment methods include:
Surgical excision of fatty tissue deposits around joints (liposuction) has been used in some cases. It may temporarily relieve symptoms although recurrences often develop.
Traditional analgesics The pain in Dercum’s disease is often reported to be refractory to analgesics and to non-steroidal antiinflammatory drugs (NSAIDs). However, this has been contradicted by the findings of Herbst et al. They reported that the pain diminished in 89% of patients (n=89) when treated with NSAIDs and in 97% of patients when treated with narcotic analgesics (n=37). The dosage required and the duration of the pain relief are not precisely stated in the article.
Lidocaine An early report from 1934 showed that intralesional injections of procaine (Novocain®) relieved pain in six cases. More recently, other types of local treatment of painful sites with lidocaine patches (5%) (Lidoderm®) or lidocaine/prilocaine (25 mg/25 mg) cream (EMLA®) have shown a reduction of pain in a few cases.
In the 1980s, treatment with intravenous infusions of lidocaine (Xylocaine®) in varying doses was reported in nine patients. The resulting pain relief lasted from 10 hours to 12 months. In five of the cases, the lidocaine treatment was combined with mexiletine (Mexitil®), which is a class 1B anti-arrhythmic with similar pharmacological properties as lidocaine. The mechanism by which lidocaine reduces pain in Dercum’s disease is unclear. It may block impulse conduction in peripheral nerves, and thereby disconnect abnormal nervous impulse circuits. Nonetheless, it might also depress cerebral activity that could lead to increased pain thresholds. Iwane et al. performed an EEG during the administration of intravenous lidocaine. The EEG showed slow waves appearing 7 minutes after the start of the infusion and disappearing within 20 minutes after the end of the infusion. On the other hand, the pain relief effect was the greatest at about 20 minutes after the end of the infusion.
Based on this, the authors concluded that the effect of lidocaine on peripheral nerves most likely explains why the drug has an effect on pain in Dercum’s disease. In contrast, Atkinson et al. have suggested that an effect on the central nervous system is more likely, as lidocaine can depress consciousness and decrease cerebral metabolism. In addition, Skagen et al. demonstrated that a patient with Dercum’s disease lacked the vasoconstrictor response to arm and leg lowering, which indicated that the sympathicusmediated local veno-arteriolar reflex was absent. This could suggest increased sympathetic activity. An infusion of lidocaine increased blood flow in subcutaneous tissue and normalised the vasoconstrictor response when the limbs were lowered. The authors suggested that the pain relief was caused by a normalisation of up-regulated sympathetic activity.
Methotrexate and infliximab One patient’s symptoms were improved with methotrexate and infliximab (Remicade). However, in another patient with Dercum’s disease, the effect of methotrexate was discreet. The mechanism of action is unclear. Previously, methotrexate has been shown to reduce neuropathic pain caused by peripheral nerve injury in a study on rats. The mechanism in the rat study case was thought to be a decrease in microglial activation subsequent to nerve injury. Furthermore, a study has shown that infliximab reduces neuropathic pain in patients with central nervous system sarcoidosis. The mechanism is thought to be mediated by tumour necrosis factor inhibition.
Interferon α-2b Two patients were successfully treated with interferon α-2b. The authors speculated on whether the mechanism could be the antiviral effect of the drug, the production of endogenous substances, such as endorphins, or interference with the production of interleukin-1 and tumour necrosis factor. Interleukin-1 and tumour necrosis factor are involved in cutaneous hyperalgesia.
Corticosteroids A few patients noted some improvement when treated with systemic corticosteroids (prednisolone), whereas others experienced worsening of the pain. Weinberg et al. treated two patients with juxta-articular Dercum’s disease with intralesional injections of methylprednisolone (Depo-Medrol). The patients experienced a dramatic improvement. The mechanism for the pain-reducing ability of corticosteroids in some conditions is unknown. One theory is that they inhibit the effects of substances, such as histamine, serotonin, bradykinin, and prostaglandins. As the aetiology of Dercum’s disease is probably not inflammatory, it is plausible that the improvement some of the patients experience when using corticosteroids is not caused by an anti-inflammatory effect.
CVAC sessions Dr. Karen Herbst conducted a pilot study utilizing CVA sessions in 2010. A touch-free method was utilized, which is delivered via a high-performance altitude or pressure simulator, the Cyclic Variations in Adaptive Conditioning (CVAC) process. As a pilot study, 10 participants with AD completed pain and quality of life questionnaires before and after 20–40 minutes of CVAC process daily for 5 days. The Cyclic Variations in Adaptive Conditioning (CVAC)(CVAC Systems, Inc; Temecula, California, USA) process is an alternative and potentially revolutionary method of touch free cyclic hypobaric pneumatic compression for treatment of tissue edema and, therefore, edema-associated pain. The CVAC process is currently available for improved fitness only. It is not available to diagnose or treat any disease or other medical condition. Furthermore, CVAC Systems, Inc. makes no claims as to the effectiveness, efficacy or safety of the CVAC process for therapeutic applications.