Degos Disease 

Updated: Dec 10, 2019
Author: Meagan O Harris, MD; Chief Editor: Dirk M Elston, MD 

Overview

Background

In 1941, in an article entitled "Multiple Hautrekrosen bei Thromboangiitis obliterans," Kohlmeier described a case of a disease that has now been termed malignant atrophic papulosis (MAP) or Degos disease. Degos recognized it as a distinct clinical entity in 1942.

Research suggests that Degos disease is a genetic disease of complement or some other clotting factor or system.[1] This is supported by the fact that eculizumab, a C5 blocker, can effectively treat systemic Degos disease.

Broadly speaking, Degos disease is a vasculopathy or an endovasculitis. It is an occlusive arteriopathy involving small-caliber vessels. Specifically, it is a progressive, small- and medium-size arterial occluding disease, leading to tissue infarction and initially involving the skin. Degos disease occurs both in a limited benign, cutaneous form and in a potentially lethal multiorgan, systemic variant.[2]

In the skin, Degos disease initially manifests with erythematous, pink or red papules. These papules heal to leave scars with pathognomonic, central, porcelain white atrophic centers. These papules usually have a peripheral telangiectatic rim.

In the systemic variant of Degos disease, the gastrointestinal tract is affected in 50% of cases. Intestinal perforation is the most severe complication and the most common cause of death in systemic Degos disease.[3] Other systems can also be involved; approximately 20% of cases of systemic Degos disease involve the CNS. Systemic manifestations usually develop from weeks to years after the onset of skin lesions, or, in rare instances, they may precede the skin lesions.

Because of the broad overlap in clinical and histological findings, High et al[4] contended in 2004 that Degos disease may not be a specific entity but, rather, may represent a common end point to a variety of vascular insults, many of which have not been fully elucidated. In 2003, Ball et al[5] proposed that Degos disease is just a variant of lupus.

Unlike lupus, (1) Degos disease does not involve the face, (2) it does not respond to therapies such as corticosteroids that at least abate lupus, (3) it does not manifest with photosensitivity, (4) viral inclusions are present in some cells in patients with Degos disease, and (5) systemic Degos disease is universally fatal, usually within 1-2 years, whereas lupus (even if severe) takes years to be fatal.[6]

Guhl has noted a case of Wegener granulomatosis that manifested with multiple whitish papules, perhaps similar to those in Degos disease.[7]

New cases of Degos disease continue to be described, with no fully effective cure yet devised.[8, 9]

Pathophysiology

The etiology and the pathophysiology of Degos disease are unknown. Some have classified Degos disease as a vasculitis, a mucinosis, or a thrombotic disorder. The most commonly suggested hypotheses are vasculitis, coagulopathy, and primary endothelial dysfunction.[10] In most cases, no circulating immune complexes, antiendothelial cell antibodies, or anticardiolipin antibodies are isolated. Although, in some cases, antiphospholipid antibodies of uncertain significance are identified. A source of confusion exists in understanding atrophic papulosis. It is likely that the differences in blood vessels in each area of the body (eg, skin, brain, intestines) help explain the different phenotypes of disease.

Some authorities suggest that the primary endothelial cell defect with secondary thrombosis leads to infarctive changes manifesting as Degos disease. No evidence exists supporting specific antibody-mediated damage. Additionally, medications and toxic chemicals do not appear to induce Degos disease.

The actual physical damage to blood vessels involves, at least in part, impaired fibrinolytic activity and alterations in platelet function. Classifying Degos disease as a vasculitis may not be appropriate because inflammation of the vessel walls is minimal and because immune complexes have not been found in the vessel walls.

Three possible mechanisms for this pathology have been suggested: disturbance in immunity, viral infection, and abnormality in the clotting system of blood.

In familial cases, an autosomal dominant mode of inheritance has been suggested, but this is uncertain.

In molecular analysis of cases of Degos disease with only cutaneous lesions, no paramyxovirus was identified by polymerase chain reaction.

The effectiveness of eculizumab at treating Degos disease must transform our understanding of the disease. As eculizumab is a hematological drug that blocks complement component 5 (C5), Degos disease may, in fact, be a hematological/endothelial/clotting disease that involves C5 in some pathological cascade. A genetic defect that parallels that of paroxysmal nocturnal hemoglobinuria (PNH) would not be surprising. Scheinfeld has discussed this concept at length.[11]

Support for the idea that Degos disease is an genetic defect of the endothelial tissue (with or with out a viral trigger) comes from Passarini who noted that in a patient suffering from systemic Degos disease who received an organ transplant, who died, on autopsy did not have any Degos disease–like changes in the transplanted tissue.[12]

A report from Japan published in 2013 investigated the expression of stromal cell–derived factor (SDF)-1/CXCL12 in Degos disease. Bone marrow stromal and endothelial cells secrete SDF-1/CXCL12. SDF-1/CXCL12 activates megakaryocyte precursors. SDF-1/CXCL12 co-stimulates platelet activation. The study compared 2 patients with Degos disease, 1 patient with cryoglobulinemia, 1 patient with antiphospholipid syndrome, and 2 healthy controls. No staining was noted in the antiphospholipid syndrome, cryoglobulinemia, or control subjects. In the Degos disease patients, investigators saw intense SDF-1/CXCL12 staining infiltrating inflammatory cells. These cells were located in the perivascular, intravascular, and perineural tissue. This finding supports the theory that Degos disease is perhaps, in part, an endothelial disease.[13]

Etiology

The cause of Degos disease is unknown. Suggested causes include a virus, an immune defect, or a clotting defect.

Epidemiology

Frequency

Degos disease is rare. About 200 cases have been reported in the world literature.[14] The exact incidence of this disease is unknown, likely owing to its nonspecific clinical presentation leading to possible misdiagnosis.

Race

Some state that Degos disease generally occurs in white young adults. However, Degos disease is reported in blacks in Africa, Arabs in Jordan,[15] Asians in Japan, and elsewhere. Any racial link is uncertain.

Sex

A slight female predominance has been noted in the most recent literature. Theodoridis et al[10] noted a female-to-male ratio of 1.4:1, and Wilson et al[16] noted that benign malignant atrophic papulosis is more commonly reported in women, at a female-to-male ratio of 3:1.

Age

All ages are affected, but the disease typically presents between the second and fifth decades of life.[17] In one study by Theodoridis et al,[10] the mean age of onset was 35.4 ± 12.3 years.

Wilson et al[16] looked at 34 patients with benign cutaneous malignant atrophic papulosis and found their average age was 37.6 years.

There are several cases in children as outlined below, presenting as early as age 7 months.

In 1999, Lankisch et al[18] described a 16-year-old white adolescent girl with acute abdominal pain due to visceral involvement of Degos disease that required extensive small-bowel resection. The skin manifestations had been present for 2 years before the correct diagnosis was made. She died as a result of CNS involvement from Degos disease.

Jalil et al[19] described a case in a 2-year-old child who presented with chronic abdominal pain of uncertain origin.

Huang et al reported a case in a 4-year-old girl with papules appearing during infancy, who presented with sudden-onset unilateral ptosis, a single episode of abdominal pain, and unremarkable family history. The patient's neurological function gradually deteriorated over 2 months to complete paralysis with trace eye movement until the patient expired about 2 years later due to multiple intracranial hemorrhages.[20]

Degos disease was also reported in a 7-month-old girl who showed spontaneous aggregation of platelets. A good clinical response in this patient was obtained by treatment with aspirin and dipyridamole.[21]

Prognosis

The presence of systemic symptoms is the most important prognostic factor. Gastrointestinal involvement may occur in as many as 60% of patients, and death in such cases is likely. About 15% of patients with Degos disease have long-term survival, with disease often limited to the skin and with no manifestations of fatal bowel or CNS involvement.

Systemic Degos disease is frequently fatal within 2-3 years from the onset of systemic involvement. The cause of death is usually intestinal perforation. However, the range of survival time from time of diagnosis varies from less than 1 year to more than 12 years. Other causes of death include bowel infarction, pleuropericardial pathology,[22] and neurologic infarction and hemorrhage.

Wilson et al[16] reviewed the 24 reported instances of malignant atrophic papulosis malignant/systemic type and benign/purely cutaneous type in pediatric patients. They found that 14 cases (58%) were fatal. Patients died an average of 3.6 years after the diagnosis of malignant atrophic papulosis.

In one patient, in whom skin and abdominal symptoms occurred at the same time, death from bowel hemorrhage followed in 6 months.

In 1996, Subbiah et al[23] described the neurologic features of a series of 15 patients with Degos disease at the Mayo Clinic. Each patient had the white papules that are the hallmark of Degos disease (biopsy proven). Long-term follow-up revealed 6 patients were dead. Nine patients with skin lesions only were nearly asymptomatic. Immunosuppressive and antiplatelet agents did not halt disease progression. CNS infarcts and hemorrhages with intravascular thrombi and without evidence of vasculitis were notable findings at autopsy.

Patient Education

Because cutaneous lesions most often precede systemic symptoms,[17] it is important to discuss potential complications and their warnings signs with patients so that they may present for prompt evaluation and management of these potential complications.

 

Presentation

History

Degos disease, also known as malignant atrophic papulosis or Kohlmeier-Degos disease, is a rare disorder resulting from a vasculopathy, which can affect the skin, gastrointestinal tract, and CNS.[17] The pathognomonic skin lesions have a porcelain-white atrophic center and erythematous telangiectatic rim. Although the disease can affect patients of any age, it typically presents between the second and fifth decades of life.[17] One study by Theodoridis et al[10] described a mean age of onset of 35.4 years (± 12.3 years), with a female-to-male ratio of 1.4:1.

Prognosis is primarily determined by the existence of systemic involvement.[10] A 2018 study by Hu et al described a median of 2 years after diagnosis of Degos disease to the presentation of other systemic symptoms.[24] In this study, the gastrointestinal tract was involved in 82.7% of patients and the CNS in 42.3%.

Patients with Degos disease may note abdominal, neurological, ophthalmological, or pulmonary complaints, including abdominal pain, abdominal distention, cramps, nausea, vomiting, diarrhea, constipation, facial and acral paresthesia, headaches, dizziness, seizures, hemiplegia, aphasia, paraplegia, gaze palsy, diplopia, ptosis, visual-field defects, weakness, shortness of breath, and chest pain. It is important to obtain a proper review of systems, and positive findings should elicit further investigation and workup.

Familial Degos disease has been reported in several cases. In 1997, Katz et al[25] described a familial variant of Degos disease. Theodoridis et al noted familial occurrence in 9% of cases in their study.[10]

Degos disease has been associated with systemic diseases. Degos disease has occurred in patients with rheumatoid arthritis, HIV infection, and antiphospholipid antibodies and antiphospholipid syndrome.[26] Degos disease associated with a spontaneous cure of diabetes has been reported.[27] A case of Degos disease occurring with diabetes mellitus, with biopsy findings of both Degos disease and hyaline diabetic microangiopathy, has also been reported.[28]

Several cases have been reported during pregnancy or in the peripartum period. A case of Degos disease developing during early pregnancy resulting in induction of labor, with biopsy findings consistent with Degos disease with ischemic gastrointestinal complications, has been reported.[29] Hu et al[24] described a case of malignant atrophic papulosis with subsequent motor aphasia and intestinal perforation in a women 10 days after delivery of a full-term pregnancy. A benign variant developing during pregnancy has also been described.[30]

Degos disease has been described in the setting of several infections. Parvovirus B19–associated catastrophic endothelialitis with a Degos-like presentation has been noted.[31] Poststreptococcal vasculopathy that evolved into Degos disease–like white papules has been reported.[32]

Ortiz et al reported a case of cutaneous Degos disease that showed features of connective-tissue disease; a specific connective-tissue disease never developed in the patient.[33] Saglik et al[34] noted a case of malignant atrophic papulosis with endocardial involvement and positive anticardiolipin antibodies.

Physical Examination

Degos disease typically manifests with multiple, small, red, raised papules that are 2-5 mm in diameter. After a few days, they enlarge and develop a central porcelain-white atrophic appearance that is depressed in comparison to the erythematous rim, as shown in the images below. They heal, leaving depressed porcelain white scars with a rim of telangiectases. These erythematous papules with a white atrophic center, characterized as a crown of thorns, are reportedly pathognomonic of Degos disease.[35]

Lesions favor the trunk and upper extremities, but they can also be found on the penis.[36] Involvement of palms and soles and is uncommon.[36] One case has noted that Degos lesions occurred on the scalp. No cases known to the authors note Degos disease-type papules on the face.

Four papules of Degos disease located on upper-inn Four papules of Degos disease located on upper-inner arm in different stages of evolution. Courtesy of David F. Butler, MD.
Papule of Degos disease with central sclerosis and Papule of Degos disease with central sclerosis and telangiectasia. Courtesy of David F. Butler, MD.

A full physical examination should be performed, given the risks of systemic involvement, including an ophthalmologic examination, palpation, percussion and auscultation of the abdomen, auscultation of heart and lungs, and a neurologic examination.

A variety of ocular findings occur in Degos disease. Posterior subcapsular cataracts,[37] visual-field defects, ptosis, third cranial nerve palsies, blepharoptosis, and optic atrophy may be associated with Degos disease. Optical neuritis, papilledema, and scleral plaques can be present.[38] In 1986, Sibillat et al[39] reported that ophthalmologic symptoms were present in 35 of 105 extant reports of Degos disease. Degos disease manifested in the eye tissues, usually in the conjunctiva. The sclera, the episclera, the retina, the choroid, the optic nerve, and/or the neuro-ophthalmologic apparatus demonstrated damage consonant with Degos disease.

Patients experience abdominal pain. Gastrointestinal bleeding can result in vomiting blood or passing blood with bowel movements. Patients with Degos disease may have enterocutaneous fistulae.

Complications

The most common organ systems affected are the CNS and gastrointestinal tract.[24] The most frequent causes of death include cerebral infarction, intestinal perforation, and secondary peritonitis.[24]

Complications of Degos disease include the following:

  • Gastrointestinal infarcts, bleeding, and perforation
  • Central nervous system involvement, including cerebral infarcts, subarachnoid hemorrhage, and hydrocephalus, [40] as well as hemiparesis, polyradiculoneuropathy, headaches, and seizures [23]
  • Cardiac pathologic conditions, including pericardial effusions, possible pericardial thickening, and constrictive pericarditis [41]
  • Pulmonary pathologic conditions, including pleuritis and pulmonary effusions
  • Ocular complications, including visual-field defects, cataracts, ptosis, third cranial nerve palsies, blepharoptosis, optic atrophy, [37] optic neuritis, papilledema, and scleral plaques [38]

 

 

DDx

Diagnostic Considerations

Skin popping (intravenous and cutaneous microvascular drug abuse) with opiates has been reported to mimic malignant atrophic papulosis (Degos disease) with multiorgan involvement.[42]

Differential Diagnoses

 

Workup

Laboratory Studies

No specific laboratory test results are specific for a diagnosis of Degos disease; however, many patients present with abnormalities in clotting function.[17]

Imaging Studies

No imaging studies are needed to evaluate the cutaneous lesions. If organ system involvement is suspected, appropriate imaging studies should be ordered.

Neurologic evaluation should include the following:

  • MRI of the brain to evaluate for cerebral infarctions or hemorrhage [43] and cord infarcts
  • MRI of the optic nerve [38]
  • Cerebral angiography, which can depict stenosis, ectasia, and aneurysms involving the peripheral branch of arteries [43]
  • Electroencephalogram testing - May show generalized nonspecific slowing
  • Electromyogram - May demonstrate axonal and demyelinating polyneuropathy

Cardiothoracic evaluation should include a chest radiograph.

Abdominal evaluation should include CT scanning of the abdomen/pelvis.[44]

 

Other Tests

Endoscopy of the gastrointestinal tract (ie, stomach, esophagus, duodenum, colon, rectum) can show infarcted lesions or ulcers. Laparoscopy of the intestine can show a similar type lesions that manifest with white plaques with red borders on the serosal surface of the bowel and the peritoneum. Laparoscopy demonstrates superiority over endoscopy at detecting gastrointestinal involvement.[45]

Histologic Findings

Early papules in Degos disease are skin colored and can demonstrate a superficial and deep perivascular, periadnexal, and perineural chronic inflammatory cell infiltrate associated with interstitial mucin deposition, as shown in the images below.

Superficial and mid-dermal perivascular lymphocyti Superficial and mid-dermal perivascular lymphocytic infiltrate with focal vacuolar change at the dermoepidermal junction (hematoxylin and eosin, X100). Courtesy of David F. Butler, MD.
Alcian blue stain for mucin (X100). Courtesy of Da Alcian blue stain for mucin (X100). Courtesy of David F. Butler, MD.

A mild vacuolar interface reaction has been described. The vacuolar interface dermatitis, dermal mucin, and perivascular lymphoid infiltrate mimic lupus erythematosus.

Fully developed papules can be raised, with umbilicated porcelain-white centers and a surrounding erythematous rim. Histologically, these papules demonstrate wedge-shaped degeneration of collagen, as shown in the image below.

Wedge-shaped area of dermal sclerosis (hematoxylin Wedge-shaped area of dermal sclerosis (hematoxylin and eosin, X100). Courtesy of David F. Butler, MD.

An interface dermatitis can be present but is often limited to the central portion of the tissue examined histologically. Additionally, squamatization of the dermoepidermal junction, melanin incontinence, and epidermal atrophy can manifest.[46]

In many cases, an area of papillary dermal sclerosis manifests that mirrors the early stages of lichen sclerosus et atrophicus.

Hyperkeratosis, epidermal atrophy, dermoepidermal separation, edema, and papillary dermal necrosis occur. Fibrinoid necrosis and thrombosis occur in the papillary dermis and in the capillary and venules. Others have noted that skin biopsy specimens show hyperkeratosis, atrophy of the epidermis, and necrobiosis of the collagen layer. Well-developed papules of Degos disease with epidermal atrophy and hyperkeratosis overlying a wedge-shaped area of cutaneous ischemia extending into the deep dermis have also been observed.

A superficial and deep perivascular lymphocytic infiltrate can gather at the fringe of ischemic areas. Marked endothelial swelling and occasional platelet-fibrin thrombi are often noted. Infarctive changes or scattered necrotic keratinocytes may be present in the epidermis. Abundant acid mucopolysaccharides often occur in the dermis, mimicking dermal mucinosis.

Direct immunofluorescence examination does not yield definitive results. Perivascular fibrin and complement can be present. In one reported case, autopsy results demonstrated the clinical diagnosis of Degos disease based on the finding of thromboangiitis of the Burger type, with bland infarcts of the small intestine and perforation of the jejunum.

In a case of Degos disease, Cavalié et al[35] demonstrated the use of reflectance confocal microscopy (RCM) to better characterize the pathognomonic telangiectatic ring viewed on dermoscopy. RCM revealed distinct features of the lesional and perilesional regions not previously reported. The telangiectatic ring corresponded to increased and dilated dermal capillaries.

Microaneurysms of the bulbar conjunctival vessels have been described.

Changes in the kidneys manifest with thickening of the afferent glomerular arterioles and the capillary basement membrane.

In 2008, Notash et al[36] described a fatal case of Degos disease in a 48-year-old man whose autopsy findings demonstrated diffuse fibrotic changes in the serosal membranes and the internal organs.

A case of the benign variant showing histopathologic similarities with lymphocytic vasculitis and lichen sclerosus has been described. Features mimicking lichen sclerosis included vacuolization of the dermoepidermal junction, keratinocyte necrosis, epidermal atrophy, and edema of the papillary and reticular dermis.[47]

 

Treatment

Medical Care

Until 2010, no medical therapy for Degos disease was noted to be uniformly effective. Antiplatelet drugs (eg, aspirin, dipyridamole) may reduce the number of new lesions in some patients with only skin involvement. Some believe intravenous immunoglobulin may have a role in treatment.[48] This has changed with the reports that eculizumab can effectively treat systemic Degos disease.[1]

The initial enthusiasm for eculizumab as monotherapy may have faded. Burgin et al note that eculizumab (900 mg/d) failed as treatment for advanced systemic atrophic papulosis with gastrointestinal involvement, with fatality as the outcome.[49] Shapiro et al note that only two patients initially given eculizumab as monotherapy are still alive; they instead use a combination of subcutaneous treprostinil and eculizumab.[50] Eculizumab, if given early enough, may help abate malignant atrophic papulosis, but as monotherapy it is not instrumental in controlling it.  With four patients treated, there have had no deaths. The first two are now six-year survivors. Each of them had been critically ill in ICU settings prior to therapy. This information is important because malignant atrophic papulosis without treatment or hope of treatment is lethal and patients should be directed towards those experienced with treatment as eculizumab alone may not work.

Other reports[51] have supported the use of eculizumab for systemic Degos disease but informal communication to the author noted that despite treatment with eculizumab, some patients with systemic Degos disease have died. One report noted 2 patients with Degos disease in whom eculizumab failed.[52] One had overlapping lupus and the other had pulmonary hypertension. The pulmonary hypertension patient was treated with treprostinil and cutaneous MAP lesions resolved but disabling digital pain manifested. In the patient with Degos disease and lupus, treprostinil temporally resulted in clearing of hematuria, CNS symptoms and MRI finding improvements.

A presentation by Magro et al[53] reported that eculizumab, which has been approved for paroxysmal nocturnal hemoglobinuria, improved systemic Degos disease in 3 patients. This small series was uncontrolled, but the results suggest promise for eculizumab as a treatment. The effectiveness of eculizumab also may support the idea that Degos disease is not a collagen-vascular disease, but instead is an endothelial- or complement-mediated disease. Eculizumab is expensive, which may hinder its acceptance as widely used therapy.

An article published in 2013 found that exploratory treatment with eculizumab did not help the development or progression of Degos disease systemic manifestations,[14] with 5 of 7 patients’ disease initially improving but then regressing, with progression of disease in 1 immediately and the 4 others after a period of time.

A proposed new treatment for Degos disease is treprostinil, a medication for pulmonary hypertension. Shapiro et al (2013) report a series of 3 patients treated with subcutaneous treprostinil (dose not reported).[54] One patient had systemic lupus erythematosus (SLE), overlap scleroderma, extensive malignant atrophic papulosis lesions, and severe pulmonary hypertension without CNS or bowel involvement. She was placed on therapy with treprostinil for her pulmonary hypertension, but in the months subsequent to initiation of treatment, dramatic and complete resolution of cutaneous malignant atrophic papulosis–like lesions and disabling digital pain occurred. The second patient had pure malignant atrophic papulosis but progressive organ (CNS, bladder, neurological, and gross hematuria) dysfunction despite eculizumab treatment, but therapy with treprostinil was temporally associated with clearing of hematuria, resolution of CNS symptoms, and improvement in MRI findings.

Other treatments that have been tried without real effect include the following: topical corticosteroids, phenformin and ethylestrenol, iodohydroxyquinoline, aspirin and dipyridamole, phenylbutazone, arsenic, sulfonamides, dextran, corticosteroids, heparin, warfarin, niacin, streptomycin, corticotropin, azathioprine, methotrexate, cyclosporine, tacrolimus, mycophenolate mofetil, pentoxifylline, and clopidogrel.

Hohwy et al[55] treated a patient with fatal systemic malignant atrophic papulosis (MAP) with narrow-band ultraviolet (UVB) light and prednisolone and, later, with aspirin, pentoxifylline, and warfarin. Treatment was not effective. Interestingly, the patient has a mutation of factor V Leiden and lupus anticoagulant.

Care is primarily supportive. Admission to the hospital can be necessary in cases of gastrointestinal bleeding or other systemic complications.

Surgical Care

When gastrointestinal bleeding, intestinal perforation, bowel infarction, or intracranial bleeding occurs, proper surgical intervention is necessary.

Consultations

Consult the following physicians:

  • Dermatologists
  • Gastroenterologists
  • Neurologists
  • General surgeons
  • Neurosurgeons
  • Ophthalmologists

Activity

Patients are often weak and this limits their activity, but no limitation to Degos disease itself exists.

Long-Term Monitoring

Patients should be monitored for systemic manifestations of Degos disease and treated accordingly.

 

Medication

Medication Summary

Medical treatment of Degos disease is currently not well defined. Various agents have been tried, including antiplatelet agents, anticoagulants, immunosuppressive medications, fibrinolytic drugs, anti-inflammatory or vasodilator agents, and chloroquine, with varying degrees of success.[24] Several reports have described disease activity worsening during treatment with immunosuppressive agents.[56]

More recently, there has been hope for eculizumab, a monoclonal antibody targeting and inhibiting the C5 component of the complement cascade, as well as subcutaneous treprostinil, a vasodilatory agent[24] ; however, dosing and treatments guidelines have not been well established given the limited number of cases.

Anticoagulant

Class Summary

Eculizumab has been found to be a life saving drug for those with systemic Degos disease.

Eculizumab (Soliris)

This is an off-label use for Degos disease. Eculizumab blocks complement-mediated destruction of paroxysmal nocturnal hemoglobinuria red blood cells. It inhibits the C5 component of the complement system, thereby preventing the final stages of complement activation.

The drug is FDA approved to reduce hemolysis with paroxysmal nocturnal hemoglobinuria and for atypical hemolytic uremic syndrome to inhibit complement-mediated thrombotic microangiopathy.

Vasodilator

Class Summary

Prostacyclin is a strong vasodilator of all vascular beds and a potent endogenous inhibitor of platelet aggregation. Platelet effects result from activation of intracellular adenylate cyclase and from increased cyclic adenosine monophosphate (cAMP) concentrations within platelets. Prostacyclin may decrease thrombogenesis and platelet clumping in the lungs by inhibiting platelet aggregation.

Treprostinil (Tyvaso, Remodulin)

This is an off-label use for Degos disease. Treprostinil is a stable prostacyclin analogue. It elicits direct vasodilation of pulmonary and systemic arterial vessels and inhibits platelet aggregation. Vasodilation reduces right and left ventricular afterload and increases cardiac output and stroke volume.