What is Multiple Reticulohistiocytosis?
Multiple reticulohistiocytosis is a rare chronic disease of unknown etiology, in which there is damage to the joints and skin (dermatoarthritis).
Mainly women of middle age are ill. The disease is characterized by polyarthritis, skin nodules and the presence of xanthelasm on the eyelids.
According to modern data, damage to the joints and skin is due to histiocytic tissue infiltration with the formation of giant cells containing positive granules, which are glycolipids. This is associated with the second name of the disease – lipoid dermoarthritis.
Symptoms of Multiple Reticulohistiocytosis
The disease is manifested by chronic polyarthritis with a symmetrical lesion of the joints of the upper and lower extremities, very similar to rheumatoid arthritis, especially if proximal interphalangeal joints are affected. In some cases, with a lesion of the distal interphalangeal joints, the disease is similar to psoriatic arthritis, especially since dermoarthritis also has a very small swelling (roller) around the nails. Due to severe bone destruction and chronic inflammation, persistent deformity of the joints of the extremities, especially of the hands, with flexion contractures of the fingers occurs, which is why the hand acquires the characteristic appearance of a lorgnette. Sometimes the sacroiliac and spinal joints are involved in the process. Movement in the joints and walking are difficult, however, ankylosis is rarely formed. Tenosynovitis of the surrounding muscles may also be observed.
The second characteristic feature is the formation of rounded skin nodules of brown or yellowish color, with a diameter of several millimeters to several centimeters, located separately or in groups on the skin of the face, scalp, ears, back of the hands and fingers, especially around the nails. The nodules can be located on the mucous membranes, sometimes in place of these nodules ulcers form. Nodules appear and disappear.
Approximately 40% of patients on the eyelids are detected xanthelasma (xanthomas flat).
Diagnosis of Multiple Reticulohistiocytosis
X-ray. On radiographs of the joints, there are first observed bone defects in the subchondral bone, similar to the “piercers” for gout, then gradually developed severe destruction of the articular surfaces of the epiphyses until complete osteolysis of a significant part of the epiphysis develops.
Laboratory data. Blood counts may be normal. ESR is often moderately increased.
The course of the disease is chronic with periodic exacerbations and spontaneous remissions. After a few years, the process can stabilize. Progression of joint destruction can lead to disability.
Establishing diagnosis. Diagnosis is based on the presence of chronic destructive arthritis and characteristic skin nodules. However, it is often difficult and in such cases it is solved with the help of a biopsy of the affected tissues, where giant histiocytic cells containing CHIC-positive material are found.
Treatment of Multiple Reticulohistiocytosis
High-dose corticosteroids have a beneficial effect on skin lesions and arthritis (30–40 mg of prednisone per day). However, when corticosteroid therapy is discontinued, all symptoms of the disease reappear. According to the observations of A. Ryckewaert, some therapeutic effect can be achieved with the use of immunosuppressants in usual doses (leukeran, azathioprine, etc.).