Shwartzman phenomenon, also known as Shwartzman reaction, is a rare reaction of a body to particular types of toxins, called endotoxins, which cause thrombosis in the affected tissue. A clearing of the thrombosis results in a reticuloendothelial blockade, which prevents re-clearing of the thrombosis caused by a repeat introduction of the toxin. That will cause tissue necrosis. Shwartzman phenomenon is usually observed during delivery or abortion, when foreign bodies are introduced into the tissues of the female reproductive system.

The Shwartzman phenomenon is named for Gregory Shwartzman, the doctor at Mount Sinai Hospital in New York City who was the first to develop the concept of immune system hypersensitivity in the 1920s.

This reaction was experimented using "Neisseria meningitidis" endotoxin.

This is notably seen with "Neisseria meningitidis".

CREST syndrome can be noted in up to 10% of patients with primary biliary cirrhosis.

Lucio's phenomenon is treated by anti-leprosy therapy (dapsone, rifampin, and clofazimine), optimal wound care, and treatment for bacteremia including antibiotics. In severe cases exchange transfusion may be helpful.

Crest syndrome involves the production of autoimmune anti-nuclear and anti-centromere antibodies, though their cause is not currently understood. There is no known infectious cause.

The main pathological features of this disease are a vasculitis affecting all cutaneous vessels.

There are by five characteristic features:

- colonisation of endothelial cells by acid-fast bacilli

- endothelial proliferation and marked thickening of vessel walls to the point of obliteration

- angiogenesis

- vascular ectasia

- thrombosis of the superficial and mid-dermal blood vessels

The likely pathogenesis is endothelial cell injury due to colonization/invasion followed by proliferation, angiogensis, thrombosis and vessel ectasia.

Raynaud's disease, or "Primary Raynaud's", is diagnosed if the symptoms are "idiopathic", that is, if they occur by themselves and not in association with other diseases. Some refer to Primary Raynaud's disease as "being allergic to coldness". It often develops in young women in their teens and early adulthood. Primary Raynaud's is thought to be at least partly hereditary, although specific genes have not yet been identified.

Smoking increases frequency and intensity of attacks, and there is a hormonal component. Caffeine, estrogen, and non-selective beta-blockers are often listed as aggravating factors, but evidence that they should be avoided is not solid. People with the condition are more likely to have migraines and angina.

Reynolds syndrome is a rare secondary laminopathy, consisting of the combination of primary biliary cirrhosis and progressive systemic sclerosis. In some patients this syndrome has also been associated with Sjögren's syndrome and hemolytic anemia. Typical clinical features include jaundice, elevated blood levels of alkaline phosphatase, calcinosis cutis, telangiectasias, and pruritus. This disease may cause white or yellow-ish spots on the arms or legs. The syndrome, a special case of scleroderma, is named after the American physician, Telfer B. Reynolds, MD (1921–2004), who first described it. He is also known for creating one of the world's first hepatology programs at the University of Southern California.

It should not be confused with the more common Raynaud's phenomenon.

Raynaud's phenomenon, or "Secondary Raynaud's", occurs "secondary to" a wide variety of other conditions.

Secondary Raynaud's has a number of associations:

- Connective tissue disorders:

- scleroderma

- systemic lupus erythematosus

- rheumatoid arthritis

- Sjögren's syndrome

- dermatomyositis

- polymyositis

- mixed connective tissue disease

- cold agglutinin disease

- Ehlers-Danlos syndrome

- Eating disorders:

- anorexia nervosa

- Obstructive disorders:

- atherosclerosis

- Buerger's disease

- Takayasu's arteritis

- subclavian aneurysms

- thoracic outlet syndrome

- Drugs:

- beta-blockers

- cytotoxic drugs – particularly chemotherapeutics and most especially bleomycin

- ciclosporin

- bromocriptine

- ergotamine

- sulfasalazine

- anthrax vaccines whose primary ingredient is the Anthrax Protective Antigen

- stimulant medications, such as those used to treat ADHD (amphetamine and methylphenidate)

- OTC pseudoephedrine medications (Chlor-Trimeton, Sudafed, others)

- Occupation:

- jobs involving vibration, particularly drilling and prolonged use of a String trimmer (weed whacker), suffer from vibration white finger

- exposure to vinyl chloride, mercury

- exposure to the cold (e.g., by working as a frozen food packer)

- Others:

- physical trauma, such as that sustained in auto accidents or other traumatic events

- Lyme disease

- hypothyroidism

- cryoglobulinemia

- malignancy

- chronic fatigue syndrome

- reflex sympathetic dystrophy

- carpal tunnel syndrome

- magnesium deficiency

- multiple sclerosis

- erythromelalgia (clinically presenting as the opposite of Raynaud's, with hot and warm extremities) often co-exists in patients with Raynaud's)

Raynaud's can "herald" these diseases by periods of more than twenty years in some cases, making it effectively their first presenting symptom. This may be the case in the CREST syndrome, of which Raynaud's is a part.

Patients with Secondary Raynaud's can also have symptoms related to their underlying diseases. Raynaud's phenomenon is the initial symptom that presents for 70% of patients with scleroderma, a skin and joint disease.

When Raynaud's phenomenon is limited to one hand or one foot, it is referred to as Unilateral Raynaud's. This is an uncommon form, and it is always secondary to local or regional vascular disease. It commonly progresses within several years to affect other limbs as the vascular disease progresses.

The term "toxic abortion" was first used to identify this phenomenon in humans in the earliest studies of the effects of pollutants on pregnancy in 1928, "An Experimental Investigation Concerning Toxic Abortion Produced by Chemical Agents" by Morris M. Datnow M.D.

Toxic abortion chemicals studied at that time were:

Petrochemicals,

Heavy metals,

Organic solvents,

Tetrachloroethylene,

Glycol ethers,

2-Bromopropane,

Ethylene oxide,

Anesthetic gases, and

Antineoplastic drugs.

In 1932, the "Journal of State Medicine" reported on a natural variation, with the occurrence of "a considerable number of cases of toxic abortion" being caused by untreated dental caries.

Study of pollution-caused abortion in humans ceased for a considerable time, interest renewing in the 2000s. A 2009 study found that fossil fuels play a role, as "pregnant African-American women who live within a half mile of freeways and busy roads were three times more likely to have miscarriages than women who don't regularly breathe exhaust fumes." A 2011 study found a correlation between exposure to workplace toxins and spontaneous abortion, and called for further study. "Newsweek" magazine reported in May 2014 that a spike in stillborn babies in the town of Vernal, in Utah, had correlated with an increase in pollution from new gas and oil drilling. "Newsweek" reported that "Vernal’s rate of neonatal mortality appears to have climbed from about average in 2010 (relative to national figures) to six times the normal rate three years later." "Newsweek" quoted one expert's observation that "We know that pregnant women who breathe more air pollution have much higher rates of virtually every adverse pregnancy outcome that exists." A study published in the "Journal of Environmental Health" in October 2014 found tetrachloroethylene or PCE, to be "linked to increased risk for stillbirths and other pregnancy complications."

The PCE study found that "pregnancies with high exposure to PCE were 2.4 times more likely to end with stillborn babies and 1.4 times more likely to experience placental abruption — when the placenta peels away from uterine wall before delivery, causing the mother to bleed and the baby to lose oxygen — compared with pregnancies never exposed to PCE." Higher exposure lead to a 35 percent higher risk of abruption. PCE has also been tied to an increased risk for cancer. Children exposed to PCE as fetuses and toddlers are more likely to use drugs later in life. The toxin has been linked to mental illness, an increased risk of breast cancer and some birth defects. It has been tied to anxiety, depression, and impairments in cognition, memory and attention. PCE contamination has been found in the Massachusetts water supply and "on military bases across the country," and "water systems in California and Pennsylvania and have also been found to be contaminated with PCE."

In 2015, "Newsweek" reported that chemicals found in fast food wrappers multiply miscarriage risk by sixteen times.

Some instances have been reported of women intentionally seeking to induce toxic abortion, where circumstances make medical abortion difficult to obtain, by exposing themselves to environmental toxins.

Mees' lines appear after an episode of poisoning with arsenic, thallium or other heavy metals, and can also appear if the subject is suffering from renal failure. They have been observed in chemotherapy patients.

This is rare and is usually due to mutations in the R-spondin 4 (RSPO4) gene which is located on the short arm of chromosome 20 (20p13). Clinically it is manifest by the absence (anonychia) or hypoplasia (hyponuchia) of finger- and/or toenails.

Toxic abortion is observed in both humans and in animals such as cows, hares, and horses. The source notes that animal ingestion of "low quality forage having some toxicity" harms livestock health, especially with cattle and horses, leading to numerous cases of "toxic abortion, gastro-enteritis and abortion with dystrophic and haemorrhagic lesions of the foetus." Cadmium has been identified as a chemical pollutant identified with toxic abortion in animals.

IgG4-related skin disease is the recommended name for skin manifestations in IgG4-related disease (IgG4-RD). Multiple different skin manifestations have been described.

Anonychia is the absence of nails, an anomaly, which may be the result of a congenital ectodermal defect, ichthyosis, severe infection, severe allergic contact dermatitis, self-inflicted trauma, Raynaud phenomenon, lichen planus, epidermolysis bullosa, or severe exfoliative diseases.

Mees' lines or Aldrich–Mees' lines, also called leukonychia striata, are white lines of discoloration across the nails of the fingers and toes (leukonychia).

The Mazzotti reaction, first described in 1948, is a symptom complex seen in patients after undergoing treatment of onchocerciasis with the medication diethylcarbamazine (DEC). Mazzotti reactions can be life-threatening, and are characterized by fever, urticaria, swollen and tender lymph nodes, tachycardia, hypotension, arthralgias, oedema, and abdominal pain that occur within seven days of treatment of microfilariasis. The Mazzotti reaction correlates with intensity of infection; however, there are probably multiple infection intensity-dependent mechanisms responsible for mediating this complex reaction.

The phenomenon is so common when DEC is used for the treatment of onchocerciasis that this drug is the basis of a skin patch test used to confirm that diagnosis. The drug patch is placed on the skin, and if the patient is infected with the microfilaria of "O. volvulus", localized pruritus and urticaria are seen at the application site.

A case of the Mazzotti reaction has been reported after presumptive treatment of schistosomiasis and strongyloidiasis with ivermectin, praziquantel and albendazole. The patient had complete resolution of symptoms after intravenous therapy with methylprednisolone.

Although a clear understanding of the various skin lesions in IgG4-related disease is a work in progress, skin lesions have been classified into subtypes based on documented cases:

- Angiolymphoid hyperplasia with eosinophilia (or lesions that mimic it) and cutaneous pseudolymphoma

- Cutaneous plasmacytosis

- Eyelid swelling (as part of Mikulicz's disease)

- Psoriasis-like eruptions

- Unspecified maculopapular or erythematous eruptions

- Hypergammaglobulinemic purpura and urticarial vasculitis

- Impaired blood supply to fingers or toes, leading to Raynaud's phenomenon or gangrene

Note:

In addition, Wells syndrome has also been reported in a case of IgG4-related disease.

Scleromyositis or the PM/Scl overlap syndrome is a complex autoimmune disease (a disease in which the immune system attacks the body). Patients with scleromyositis have symptoms of both systemic scleroderma and either polymyositis or dermatomyositis, and is therefore considered an overlap syndrome. Although it is a rare disease, it is one of the more common overlap syndromes seen in scleroderma patients, together with MCTD and Antisynthetase syndrome. Autoantibodies often found in these patients are the anti-PM/Scl (anti-exosome) antibodies.

The symptoms that are seen most often are typical symptoms of the individual autoimmune diseases and include Raynaud's phenomenon, arthritis, myositis and scleroderma. Treatment of these patients is therefore strongly dependent on the exact symptoms with which a patient reports to a physician and is similar to treatment for the individual autoimmune disease, often involving either immunosuppressive or immunomodulating drugs.

- Clinical characteristics:

- Overlap Syndrome: scleroderma overlap syndrome

- Autoimmune disease

- Scleroderma myositis overlap syndrome

Management of these partial-thickness wounds has been influenced by the Winter principle of moist wound healing, which suggests that wounds heal more rapidly in a moist environment. Hydrocolloid dressings applied directly to these wounds prevent the evaporation of moisture from the exposed dermis and create a moist environment at the wound site that promotes cell migration.

Scleroderma overlap syndrome: Scleroderma is a connective tissue disease that causes fibrosis and vascular abnormalities, but that also has an autoimmune component.

It is described by connective tissues complications. Blood testing includes screening for the positive antinuclear antibody.

Patients have symptoms of both systemic scleroderma and/or polymyositis and dermatomyositis.

1. Scleroderma: a group of rare diseases that involve the hardening and tightening of the skin and connective tissues

and/or:

Polymyositis: a rare inflammatory disease that causes muscle weakness affecting both sides of your body

Dermatomyositis: an inflammatory disease of skin and muscle marked especially by muscular weakness and skin rash.

Uveoparotitis is a symptom of sarcoidosis. It describes a chronic inflammation of the parotid gland and uvea. There is also a phenomenon called Waldenström's uveoparotitis. In this case, the symptom is related to Heerfordt's syndrome.

Moist desquamation is a description of the clinical pattern seen as a consequence of radiation exposure where the skin thins and then begins to weep because of loss of integrity of the epithelial barrier and decreased oncotic pressure. Typically this occurs at doses of 15–20 Gray, far higher than any diagnostic scan and more typical of levels seen in radiotherapy or deployment of nuclear armament. Historically, this was a common phenomenon in Hiroshima and Nagasaki during World War II with the atomic bomb attacks from the United States.

The phenomenon was famously described by John Hersey in his article, and later book, Hiroshima.

It is relatively unusual (25% of the total number of cases) for cholesterol emboli to occur spontaneously; this usually happens in people with severe atherosclerosis of the large arteries such as the aorta. In the other 75% it is a complication of medical procedures involving the blood vessels, such as vascular surgery or angiography. In coronary catheterization, for instance, the incidence is 1.4%. Furthermore, cholesterol embolism may develop after the commencement of anticoagulants or thrombolytic medication that decrease blood clotting or dissolve blood clots, respectively. They probably lead to cholesterol emboli by removing blood clots that cover up a damaged atherosclerotic plaque; cholesterol-rich debris can then enter the bloodsteam.

Sclerodactyly is a localized thickening and tightness of the skin of the fingers or toes. Sclerodactyly often leads to ulceration of the skin of the distal digits and is commonly accompanied by atrophy of the underlying soft tissues.

The term "sclerodactyly" is made up from the Greek "skleros" meaning hard and "daktylos" meaning a finger or toe – "hard fingers or toes".

It is sometimes associated with scleroderma and mixed connective tissue disease, auto-immune disorders.

Sclerodactyly is a component of the CREST variant of scleroderma (CREST is an acronym that stands for calcinosis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly, and telangiectasia.)

When skin is blanched, it takes on a whitish appearance as blood flow to the region is prevented. This occurs during and is the basis of the physiologic test known as diascopy.

Blanching of the fingers is also one of the most clinically evident signs of Raynaud's phenomenon.

Blanching is prevented in gangrene as the red blood corpuscles are extravasated and impart red color to the gangrenous part.