Overview of Recurrent Febrile Nodular Lipomatitis
Recurrent febrile nodular lipomatosis, also known as Weber-Christian syndrome, is an idiopathic form of lipomatosis involving subcutaneous adipose tissue of the trunk and thighs. The main clinical manifestation is recurrent subcutaneous nodules or flaky plaques accompanied by fever, and in some cases internal organs may be involved. Recurrent febrile nodular lipomatitis with multi-system damage is called systemic lipomatitis; those with only skin lesions and no internal organ damage are called common lipomatitis. The disease can affect both men and women, with the majority of adult cases occurring in women and the majority of child cases occurring in men. Symptoms may subside naturally after a period of fever of varying length, but complications such as cardiomyopathy, coronary artery occlusion, granulomatous pneumonia, intestinal obstruction, cirrhosis of the liver, myelofibrosis, and retroperitoneal fibrosis may occur in those who have frequent relapses over a period of months or years. Ocular damage may include uveitis, acute exudative choroiditis, and secondary glaucoma.
Etiology
The cause of the disease is still unknown, and it is generally believed that it may be a non-specific reaction caused by a variety of reasons, or an allergic disease induced by infections or drugs. According to relevant data, some cases were reported to have recurrent tonsillitis prior to the onset of the disease, and the presence of tuberculosis factor in some cases was also reported to be different, and individual cases had to be treated with anti-tuberculosis therapy in order to alleviate the disease. Drugs such as halogenated compounds, sulfonamides, and quinine may induce seborrhea, dermatomyositis, and systemic lupus erythematosus, thus suggesting that the disease is associated with autoimmune rheumatism.
Symptoms
Most cases are accompanied by prodromal symptoms such as headache, generalized weakness, anorexia, myalgia, arthralgia and mental restlessness.
1. Generalized type
(1) Fever Fever is common in the systemic type. Fever starts a few days after the appearance of skin lesions, and the body temperature rises gradually, which can be as high as 40℃ or more, showing flaccid fever, which lasts for 1～2 weeks and then begins to decline. In addition to flaccid fever, it can also be intermittent fever and irregular fever.
(2) Skin lesions: Skin lesions occur on the limbs and trunk, with the buttocks and femurs being the most common. The skin lesions are solid subcutaneous nodules occurring in batches or in pieces of different sizes; they can be as small as peas or as large as palms, with clear margins. The nodules may be adherent to the skin, with a reddish surface and mild pressure and tenderness. A few nodules may be necrotic and ulcerated, exuding a lipidic substance, but not pus. Occasionally the lesions may appear as blisters. The subcutaneous nodules may gradually disappear after a few days or weeks, and the skin in the affected area may be slightly sunken or have brown pigmentation.
(3) Joint pain Joint pain is manifested as joint pain, which is most common in both knee joints, followed by wrist joints and ankle joints, and in some cases, it may also be manifested as wandering joint pain.
(4) Enlarged lymph nodes and edema Some other patients may have enlarged lymph nodes, in which the systemic type is the most common, mostly located in the axilla, groin and trachea, with a diameter of 0.5-2 cm. Some patients may have edema, such as edema of the lower limbs, edema of the eyelids, or edema of the whole body.
2. Systemic type
(1) Respiratory system Individual patients have symptoms of chest pain and dyspnea. Vesicular sounds and pleural friction sounds can be detected on examination, and signs of exudative pleurisy can occasionally appear.
(2) Digestive system Anorexia, nausea, abdominal pain, diarrhea, jaundice, gastrointestinal bleeding, liver and spleen enlargement may occur. Lesions involving the mesentery, omentum, retroperitoneum and pelvic adipose tissue may cause epigastric pain, tenderness and poor bowel motility, and diminished bowel sounds on auscultation. This condition is called abdominal lipomatosis and is often accompanied by high fever, abdominal pain, and weight loss. Abdominal lipomatosis may lead to intestinal obstruction due to fibrosis.
(3) Cardiovascular system It may be manifested as myocarditis, cardiac hypertrophy, tachycardia, and occasionally pericarditis, and heart failure may occur later in the course of the disease.
(4) Ocular damage Some cases may present with ocular symptoms, such as anterior uveitis, acute exudative choroiditis and secondary glaucoma.
(5) Central Nervous System It may manifest as mental disorders, impaired consciousness, coma, convulsions, meningitis symptoms and intracranial hypertension, which are due to intracranial adipose tissue inflammation.
(6) Overlap with other rheumatic diseases The disease may overlap with rheumatoid arthritis, rheumatic fever, ulcerative colitis and systemic lupus erythematosus, in addition to glomerulonephritis.
Examination
（Laboratory tests
1. Blood, bone marrow and blood sedimentation
In peripheral blood, there is decrease in red blood cell count and platelet count; decrease in white blood cell count, which may contain toxic particles; decrease in neutrophil count with left shift of nucleus; however, in case of infection, the white blood cell count will increase and the sedimentation rate will increase. Bone marrow image can be seen in granulocytes, erythrocytes and megakaryocytes with different degrees of reduction, sometimes granulocytes can contain a few toxic particles, showing infected bone marrow image.
2. Urine routine
When combined with glomerulonephritis or overlapped with other rheumatic diseases, proteinuria, hematuria and tubular urine may appear.
3. Biochemical examination
Liver involvement may be characterized by abnormal liver function and increased CRP.
4. Immunologic examination
Some patients have elevated anti-“O” titer, elevated rheumatoid factor titer when overlapping with other rheumatic diseases, positive antinuclear antibody, decreased complement, elevated IgG, IgM, low function of cellular immunity test, and decreased lymphocyte conversion rate.
(II) Other auxiliary examinations
1. X-ray examination
Chest radiographs show enlarged hilar and paratracheal lymph nodes, occasionally a small amount of pleural effusion, increased texture and punctate shadows in the lungs, etc. Involvement of the cardiovascular system may be seen. If the cardiovascular system is involved, heart enlargement and heart failure can be seen.
2. Electrocardiogram
Sinus tachycardia, different types of conduction block and myocarditis can be seen.
3.Ultrasound
Imaging shows subcutaneous nodules, which manifest as thickening of the subcutaneous space at the margins of the lesion and diffuse parenchymal-like structures.
Diagnosis
The common type is not difficult to diagnose based on recurrent subcutaneous nodules or flaky plaques, accompanied by fever, and localized depressions left after spontaneous regression of the lesions. The final diagnosis depends on biopsy. The diagnosis of the systemic type is more complicated. In addition to the general clinical manifestations such as fever and subcutaneous nodules, there are also manifestations of organ involvement. In some patients, there is neither fever nor subcutaneous nodules, but only symptoms of organ involvement, and biopsy is needed to confirm the diagnosis.
Treatment
1. Remove triggering factors
For example, remove the infected lesions, stop using the drugs that induce the disease, and so on.
2. General treatment
Acute attacks should be bed rest, combined with oral, ear, nose and throat chronic infection, should be given a sufficient amount of effective antibiotics to control the infection. Avoid the use of sulfonamides as much as possible, such drugs into the body can easily play a semi-antigenic effect and aggravate the condition.
3.Systemic treatment
In the early stage, anti-rheumatic drugs can be used to relieve symptoms, reduce fever and joint pain. Non-steroidal anti-inflammatory drugs, such as aspirin or diclofenac (Fitalin), can be taken orally. If this is not effective, glucocorticosteroids, such as prednisone, may be added, and the dosage may be reduced and tapered off as soon as the symptoms are relieved. Antibiotics and hormonal drugs can be used together to achieve better results. However, it should be noted that with the evolution of the disease, the response of this disease to hormone therapy is getting worse and worse, at this time, we can change the appropriate amount of cytotoxic drugs such as cyclophosphamide, azathioprine, antimalarial drug chloroquine and immunomodulatory drugs levamisole.
4. Symptomatic treatment
Atropine antispasmodic drugs can be used to relieve abdominal pain, heart failure can be given the appropriate amount of digitalis (digitalis) preparations; edema can be used in severe cases of diuretics to relieve edema; secondary glaucoma in the eye, surgery should be used as appropriate.