All patients with symptomatic cryoglobulinemia are advised to avoid, or protect their extremities, from exposure to cold temperatures. Refrigerators, freezers, and air-conditioning represent dangers of such exposure.

Individuals found to have circulating cryoglobulins but no signs or symptoms of cryoglobulinemic diseases should be evaluated for the possibility that their cryoglobulinemia is a transient response to a recent or resolving infection. Those with a history of recent infection that also have a spontaneous and full resolution of their cryoglobulinemia need no further treatment. Individuals without a history of infection and not showing resolution of their cryoglobulinemia need to be further evaluated. Their cryoglobulins should be analyzed for their composition of immunoglobulin type(s) and complement component(s) and examined for the presence of the premalignant and malignant diseases associated with Type I disease as well as the infectious and autoimmune diseases associated with type II and type III disease. A study conducted in Italy on >140 asymptomatic individuals found five cases of hepatitis C-related and one case of hepatitis b-related cryoglobulinemia indicating that a complete clinical examination of asymptomatic individuals with cryoglobulinemia offers a means for finding people with serious but potentially treatable and even curable diseases. Individuals who show no evidence of a disease underlying their cryoglobulinemia and who remain asymptomatic should be followed closely for any changes that may indicate development of cryoglobulinemic disease.

Ultrasonography and magnetic resonance imaging of the hands and/or feet have been proposed as useful diagnostic investigations in RS3PE.

Some studies linked RS3PE to HLA-B27 whereas others have not.

In addition to tests corresponding to the above findings (such as EMG for neuropathy, CT scan, bone marrow biopsy to detect clonal plasma cells, plasma or serum protein electrophoresis to myeloma proteins, other tests can give abnormal results supporting the diagnosis of POEMS syndrome. These included raised blood levels of VEGF, thrombocytes, and/or erythrocyte parameters.

Suggested diagnostic criteria for cryoglobulinemic disease fall into the following obligatory and additional categories:

- Obligatory criteria: 1) cold sensitivity; 2) cutaneous symptoms (i.e. urticaria, purpura, Raynaud phenomenon, ulceration/necrosis/gangrene, and/or livedo reticularis); 3) arterial and/or venous thrombotic events; fever; 4) arthralgia/myalgia; 5) neuritis in >1 site; and 6) renal disorder.

- Additional criteria: 1) typical biopsy findings at site(s) of involvement and 2) angiogram evidence of occlusion in one or more small to medium sized arteries.

The diagnosis of secondary cryofibrinogenemia also requires evidence for the cited infectious, malignant, premalignant vasculitis, and autoimmune disorders while the diagnosis of primary cryofibriongenemia requires a lack of evidence for 1) the cited associated disorders, 2) other vascular occlusive diseases, and 3) cryoglobulinemia.

Patients diagnosed as having Castleman disease but also exhibiting many of the symptoms and signs of POEMS syndrome but lacking evidence of a peripheral neuropathy and/or clonal plasma cells should not be diagnosed as having POEMS syndrome. They are better classified as having Castleman disease variant of POEMS syndrome. These patients may exhibit high blood levels of the interleukin-6 cytokine and have an inferior overall survival compared to POEMS syndrome patients. Treatment of patients with this POEMS syndrome variant who have evidence of bone lesions and/or myeloma proteins are the same as those for POEMS syndrome patients. In the absence of these features, treatment with rituximab, a monoclonal antibody preparation directed against B cells bearing the CD20 antigen, or siltuximab, a monoclonal antibody preparation directed against interleukin-6, may be justified.

Two elements are considered: radiology and joint fluid analysis.

Radiology has a large role to play in finding chondrocalcinosis, with radiographs, CT scans, MRIs, US, and nuclear medicine all having a part. CT scans and MRIs show calcific masses (usually within the ligamentum flavum or joint capsule), however radiography is more successful. At ultrasound, chondrocalcinosis may be depicted as echogenic foci with no acoustic shadow within the hyaline cartilage. As with most conditions, CPPD can present with similarity to other diseases such as ankylosing spondylitis and gout.

Arthrocentesis, or removing synovial fluid from the affected joint, is performed to test the synovial fluid for the calcium pyrophosphate crystals that are present in CPPD. When stained with H&E stain, calcium pyrophosphate crystals appears deeply blue ("basophilic"). However, CPP crystals are much better known for their rhomboid shape and weak positive birefringence on polarized light microscopy, and this method remains the most reliable method of identifying the crystals under the microscope. However, even this method suffers from poor sensitivity, specificity, and inter-operator agreement.

These two modalities currently define CPPD disease but lack diagnostic accuracy, and are potentially epiphenomenological.

Success in treating the primary disease has been reported using blood clot lysing agents such as anabolic steroids (e.g. danazol or stanozolol which is no longer available in the USA), streptokinase, and streptodornase; anticoagulants such as heparin and warfarin, and immunosuppressive drug regimens such as a corticosteroid (e.g. prednisone) combined with either azathioprine of chlorambucil. Very moderate cases may do well by simply avoiding cold exposure. Treatment with a corticosteroid plus low-dose aspirin followed by maintenance therapy with an anabolic steroid where necessary are recommended for moderately severe cases. Very severe cases generally require an immunosuppressive drug regimen and if extreme or life threatening require resorting to plasmaphoresis or plasma exchange. Cryofiltration apheresis, a method to remove plasma agents by removing cold-induced precipitated material, may be an effective alternative to plasmaphoresis and plasma exchange but is still regarded as second-line therapy for cryofibirnogenemic disease treatment.

During the several years following its initial diagnosis, some 27-47% of primary cryofibrinoginemic diseases are complicated by the development of a B-cell or T-cell lymphoma. That is, the cryofibrinoginemic disease may appear to precede by years the malignant disorder to which it is associated. Accordingly, patients require careful follow-up not only to treat their primary cryofibrinoginemic disease but also to monitor them for movement to the diagnosis of secondary cryofibrinoginemic disease caused by the development of one of these hematological malignancies.

Initially, the clinical presentation of SDS may appear similar to cystic fibrosis. However, CF can be excluded with a normal chloride in sweat test but faecal elastase as a marker of pancreatic function will be reduced. The variation, intermittent nature, and potential for long-term improvement of some clinical features make this syndrome difficult to diagnose. SDS may present with either malabsorption, or hematological problems. Rarely, SDS may present with skeletal defects, including severe rib cage abnormalities that lead to difficulty in breathing. Diagnosis is generally based on evidence of exocrine pancreatic dysfunction and neutropenia. Skeletal abnormalities and short stature are characteristics that can be used to support the diagnosis. The gene responsible for the disease has been identified and genetic testing is now available. Though useful in diagnostics, a genetic test does not surmount the need for careful clinical assessment and monitoring of all patients.

Blood tests show a high concentration of specific gamma-globulins (monoclonal gammopathy) of the IgM type. It almost always has light chains of the κ-type. A variant in which IgG is raised has been described, which appears to be ten times as rare. The immunoglobulins may show up in the urine as Bence Jones proteins. Signs of inflammation are often present: these include an increased white blood cell count (leukocytosis) and a raised erythrocyte sedimentation rate and C-reactive protein. There can be anemia of chronic disease. Bone abnormalities can be seen on radiological imaging (often increased density or osteosclerosis) or biopsy.

Because it is such a rare condition (as of September 2014, only 281 cases have been reported), it is important to rule out other conditions which can cause periodic fevers, paraproteins or chronic hives. These include (and are not limited to) autoimmune or autoinflammatory disorders such as adult-onset Still's disease, angioedema, hematological disorders such as lymphoma or monoclonal gammopathy of undetermined significance, other causes of hives, cryoglobulinemia, mastocytosis, chronic neonatal onset multisystem inflammatory disease or Muckle–Wells syndrome.

It is however possible to have more than one rare condition as seen by a patient with Schnitzler's syndrome and cold induced urticaria.

A meeting of experts, including Dr Liliane Schnitzler (then retired) took place in Strasbourg in May 2012 and drew up diagnostic criteria known as the "Strasbourg Criteria". These included two obligate criteria (chronic urticarial rash and monoclonal IgM or IgG) and several minor criteria; a definite diagnosis requires the two obligate criteria and two minor criteria if IgM, three if IgG; a probable diagnosis requires the two obligate criteria and one (IgM) or two (IgG) minor criteria.

Arthritis mutilans' parent condition psoriatic arthritis leaves people with a mortality risk 60% higher than the general population, with premature death causes mirroring those of the general population, cardiovascular issues being most common. Life expectancy for people with psoriatic arthritis is estimated to be reduced by approximately 3 years.

The life span in patients with Schnitzler syndrome has not been shown to differ much from the general population. Careful follow-up is advised, however. A significant proportion of patients develops a lymphoproliferative disorder as a complication, most commonly Waldenström's macroglobulinemia. This may lead to symptoms of hyperviscosity syndrome. AA amyloidosis has also been reported in people with Schnitzler syndrome.

aHUS is not the only condition that causes systemic TMA, a fact that makes differential diagnosis essential. Historically, the clinical diagnosis of TMA-causing diseases was grouped into a broad category that (in addition to aHUS) included thrombotic thrombocytopenic purpura (TTP) and Shiga-toxin-producing Escherichia coli hemolytic uremic syndrome (STEC-HUS). However, it is now understood that although aHUS, STEC-HUS, and TTP have similar clinical presentations, they have distinct causes and specific tests can be conducted to differentiate these diseases. In addition, there are other conditions that can cause TMA as a secondary manifestation; these entities include systemic lupus erythematosus (SLE), malignant hypertension, progressive systemic sclerosis (PSS, also known as scleroderma), the pregnancy-associated HELLP (hemolysis, liver dysfunction, and low platelets) syndrome, and toxic drug reaction (e.g., to cocaine, cyclosporine, or tacrolimus). Nevertheless, aHUS should be suspected in patients presenting with systemic TMA, and appropriate diagnostic work-up should be undertaken.

The neurological and kidney-related signs and symptoms of aHUS overlap with those of TTP. However, unlike aHUS, TTP is primarily an autoimmune disorder in which the presence of an inhibitory autoantibody results in severe deficiency of ADAMTS13, an enzyme that cleaves von Willebrand factor (vWf), a large protein involved in blood clotting, into smaller pieces. (TTP also can be a genetic disorder characterized by mutations in the ADAMTS13 gene leading to severe ADAMTS13 deficiency. This congenital cause of ADAMTS13 deficiency is called Upshaw-Schülman syndrome.) A lab test showing ADAMTS13 activity levels of ≤5% is indicative of TTP.

Similarly, the gastrointestinal (GI) signs and symptoms of aHUS overlap with those of STEC-HUS. Stool samples from patients with diarrhea or other GI symptoms should be tested for STEC and the presence of Shiga-toxin. However, a positive identification of Shiga-toxin, which is required to diagnose STEC-HUS, does not rule out aHUS. Nevertheless, in the appropriate clinical setting, a positive identification of Shiga-toxin makes aHUS very unlikely.

The bone edema in arthitis mutilans can be treated with TNF inhibitors in the short term: a 2007 study found that the bone edema associated with psoriatic arthritis (of which arthitis mutilans is a subtype) responded to TNF inhibitors with "dramatic" improvement, but the study was not determinative of whether TNF inhibitors would prevent new bone formation, bone fusion, or osteolysis (bone resorption).

In 1989, diagnostic criteria was created for the diagnosing of Winchester syndrome. The typical diagnosis criteria begin with skeletal radiological test results and two of the defining symptoms, such as short stature, coarse facial features, hyperpigmentation, or excessive hair growth. The typical tests that are performed are x-ray and magnetic resonance imaging. It appears that Winchester syndrome is more common in women than men. Winchester syndrome is very rare. There have only been a few individuals worldwide who were reported to have this disorder.

RS3PE responds excellently to low dose corticosteroids, with sustained and often complete remission. Non-steroidal anti-inflammatory drugs (NSAIDs) have also been used. Hydroxychloroquine has proven effective in some cases.

Typically, a diagnosis of DBA is made through a blood count and a bone marrow biopsy.

A diagnosis of DBA is made on the basis of anemia, low reticulocyte (immature red blood cells) counts, and diminished erythroid precursors in bone marrow. Features that support a diagnosis of DBA include the presence of congenital abnormalities, macrocytosis, elevated fetal hemoglobin, and elevated adenosine deaminase levels in red blood cells.

Most patients are diagnosed in the first two years of life. However, some mildly affected individuals only receive attention after a more severely affected family member is identified.About 20–25% of DBA patients may be identified with a genetic test for mutations in the RPS19 gene.

Studies show a moderate neutrophilia (less than 50%), elevated ESR (greater than 30 mm/h) (90%), and a slight increase in alkaline phosphatase (83%). Skin biopsy shows a papillary and mid-dermal mixed infiltrate of polymorphonuclear leukocytes with nuclear fragmentation and histiocytic cells. The infiltrate is predominantly perivascular with endothelial-cell swelling in some vessels, but vasculitic changes (blood clots; deposition of fibrin, complement, or immunoglobulins within the vessel walls; red blood cell extravasation;inflammatory infiltration of vascular walls) are absent in early lesions.

Perivasculitis occurs secondarily, because of cytokines released by the lesional neutrophils. True transmural vasculitis is not an expected finding histopathologically in SS.

aHUS can be inherited or acquired, and does not appear to vary by race, gender, or geographic area. As expected with an ultra-rare disease, data on the prevalence of aHUS are extremely limited. A pediatric prevalence of 3.3 cases per million population is documented in one publication of a European hemolytic uremic syndrome (HUS) registry involving 167 pediatric patients.

Genetic testing and counselling are available to help determine the risk of passing the condition onto a child. This may involve testing a sample of tissue or blood to look for signs of the genetic mutation that causes haemophilia.

A pregnant woman with a history of haemophilia in her family can test for the haemophilia gene. Such tests include:

- chorionic villus sampling (CVS) – a small sample of the placenta is removed from the womb and tested for the haemophilia gene, usually during weeks 11-14 of pregnancy

- amniocentesis – a sample of amniotic fluid is taken for testing, usually during weeks 15-20 of pregnancy

There's a small risk of these procedures causing problems such as miscarriage or premature labour, so the woman may discuss this with the doctor in charge of her care.

The clinical differential diagnosis includes pyoderma gangrenosum, infection, erythema multiforme, adverse drug reactions, and urticaria. Recurrences are common and affect up to one third of patients.

Epidemiologically, the disorder usually develops slowly and is mainly observed in people over the age of 50. It may also develop as a side-effect of treatment with some drugs that target hematological disorders, such as polycythemia vera or chronic myelogenous leukemia.

Diagnosis of myelofibrosis is made on the basis of bone marrow biopsy. A physical exam of the abdomen may reveal enlargement of the spleen, the liver, or both.

Blood tests are also used in diagnosis. Primary myelofibrosis can begin with a blood picture similar to that found in polycythemia vera or chronic myelogenous leukemia. Most people with myelofibrosis have moderate to severe anemia. Eventually thrombocytopenia, a decrease of blood platelets develops. When viewed through a microscope, a blood smear will appear markedly abnormal, with presentation of pancytopenia, which is a reduction in the number of all blood cell types: red blood cells, white blood cells, and platelets. Red blood cells may show abnormalities including bizarre shapes, such as teardrop-shaped cells, and nucleated red blood cell precursors may appear in the blood smear. (Normally, mature red blood cells in adults do not have a cell nucleus, and the presence of nucleated red blood cells suggests that immature cells are being released into the bloodstream in response to a very high demand for the bone marrow to produce new red blood cells.) Immature white cells are also seen in blood samples, and basophil counts are increased.

When late in the disease progression an attempt is made to take a sample of bone marrow by aspiration, it may result in a dry tap, meaning that where the needle can normally suck out a sample of semi-liquid bone marrow, it produces no sample because the marrow has been replaced with collagen fibers. A bone marrow biopsy will reveal collagen fibrosis, replacing the marrow that would normally occupy the space.

There is no known cure for Winchester syndrome; however, there are many therapies that can aid in the treatment of symptoms. Such treatments can include medications: anti-inflammatories, muscle relaxants, and antibiotics. Many individuals will require physical therapy to promote movement and use of the limbs affected by the syndrome. Genetic counseling is typically prescribed for families to help aid in the understanding of the disease. There are a few clinical trials available to participate in. The prognosis for patients diagnosed with Winchester syndrome is positive. It has been reported that several affected individuals have lived to middle age; however,the disease is progressive and mobility will become limited towards the end of life. Eventually, the contractures will remain even with medical intervention, such as surgery.

Because any medication that could reduce the inflammation of CPPD bears a risk of causing organ damage, treatment is not advised if the condition is not causing pain.

For acute pseudogout, treatments include intra-articular corticosteroid injection, systemic corticosteroids, non-steroidal anti-inflammatory drugs (NSAIDs), or, on occasion, high-dose colchicine. In general, NSAIDs are administered in low doses to help prevent CPPD. However, if an acute attack is already occurring, higher doses are administered. If nothing else works, hydroxychloroquine or methotrexate may provide relief.

Research into surgical removal of calcifications is underway, however this still remains an experimental procedure.