Multicentric Reticulohistiocytosis - Causes, Symptoms, Diagnosis, and Treatment

What Is Multicentric Reticulohistiocytosis?

Multicentric reticulohistiocytosis is a rare chronic disease with unknown etiopathogenesis, which is marked by the appearance of multiple papules and nodules cutaneously followed by a severe type of erosive polyarthritis along with subsequent eruptions of the mucous membrane. It can be described as the idiopathic type of non-Langerhans cell histiocytosis. Goltz and Laymon, in 1954, coined the term multicentric reticulohistiocytosis.

What Are the Synonyms of Multicentric Reticulohistiocytosis?

• Lipoid dermatitis.

• Reticulocytosis granuloma.

• Giant cell histiocytosis.

• Lipoid dermato-arthritis.

• Lipoid rheumatism.

• Reticulohistiocytosis granuloma.

What Is the Epidemiology of Multicentric Reticulohistiocytosis?

The prevalence of multicentric reticulohistiocytosis is unknown, with no more than 250 to 300 cases reported in the medical literature worldwide. The disease's incidence rate is very low.

Malignant tumors such as breast cancer, tumors of melanocyte origin, cancer of the lungs, colon cancer, and a few autoimmune disorders are associated with the disease. Female predilection is seen. The disorder is more commonly found in Western countries. It is predominantly present in the fourth to sixth decades of life among Caucasian females.

Who Is Affected by Multicentric Reticulohistiocytosis?

Multicentric reticulohistiocytosis affects females more than males at a ratio of three to one. The average age of occurrence is eight to 74. The mean age is 47 years. It is associated with some form of cancer, namely cancers of the breast, colon, and ovary.

What Is the Etiology of Multicentric Reticulohistiocytosis?

The etiopathogenesis of the disorder is not fully known. It is believed to exhibit a distinct inflammatory reaction that leads to abnormal activation and proliferation of the macrophages or histiocytes. This results in an unregulated rise in the levels of inflammatory cytokines such as tumor necrosis factor 6,12 and alpha. The disease can also be considered a paraneoplastic syndrome since it is usually found to be associated with an underlying malignancy of the colon, breast, lungs, or ovary.

What Are the Symptoms of Multicentric Reticulohistiocytosis?

The clinical manifestations of the disease involve the presence of both skin lesions and severely inflamed joints.

• Arthritis is characterized by pain, tenderness, and swelling in and around joints and is usually the first clinical manifestation of the disease. Pain and swelling occur in the joints of the hands, wrists, knees, hips, feet, elbows, and spine. The most frequently involved joint is the distal interphalangeal joint.

• Polyarthritis usually occurs symmetrically.

• Synovitis, along with thickening of the synovial sheath and tendons, is also seen in many cases. Unresolved conditions may progress to extensive inflammation and destruction of the underlying bone. The lesions follow a waxing and waning pattern.

• The condition worsens further, leading to an erosive type of polyarthritis.

• The condition finally progresses to a debilitating state with functional deformity.

• The cutaneous lesions follow the arthritic changes.

• The classical skin lesions consist of reddish-brown papules and nodules that are typically distributed on the ears, bridge of the nose, face, neck, nail folds, hands, arms, and chest.

• The lesions may occur in isolation or groups, giving a cobblestone appearance.

• Papules are sometimes seen in the nail folds, giving the appearance of coral beads.

• Sometimes hyperpigmentation is seen associated with the ridging of the nails longitudinally.

• Erythematous lesions that are present around the nostrils are believed to be a characteristic feature of multicentric reticulocytosis.

• Ulceration of skin lesions is very rare.

• Typical erythematous skin rashes tend to occur along the light-sensitive areas.

• In almost half of the cases, mucosal lesions, including the oral and nasal mucosa, are also seen.

• The most common sites involved in the oral mucosa are the tongue, labial mucosa, buccal mucosa, and gingival tissue.

• Esophageal and laryngeal involvement is also seen in a few cases, causing dysphagia (difficulty swallowing).

• The other symptoms include fever, malaise, weakness, severe weight loss, wasting of muscles, and loss of appetite in general, leading to a debilitating state for the affected individual.

• In some cases, the disease is also involved in the systemic organs, mainly the lungs, heart, and muscles.

What Is the Differential Diagnosis of Multicentric Reticulohistiocytosis?

• Rheumatoid Arthritis- An inflammatory disease of the joints.

• Leprosy- A chronic infectious disease causing skin lesions.

• Dermatomyositis- An inflammatory disorder marked by weakness in muscles and skin rash.

• Xanthogranulomas- A rare disorder characterized by yellow or brown nodules on the face and neck skin.

• Sarcoidosis- A disorder characterized by tiny clusters of inflammatory cells throughout the body.

• Lymphoma- Cancer of the lymphatic system.

What Are the Diagnostic Methods for Multicentric Reticulohistiocytosis?

• X-Rays - Radiological imaging is an important diagnostic aid for diagnosing disease. Subchondral resorptions with sharp and symmetrical marginal erosions, along with joint space widening, are the most common radiographic findings.

• Computed Tomography- It is useful for evaluating the pathology of internal organs.

• Magnetic Resonance Imaging- It is used to evaluate any underlying systemic pathologies.

• Biopsy- Histopathology and immunohistochemical studies are the main diagnostic tests used to confirm the diagnosis of the disease.

What Is the Treatment of Multicentric Reticulohistiocytosis?

No particular treatment for the disease is available because of the limited clinical trials on patients. The disease can progress to a debilitating state if left unresolved for a longer period of time. Symptomatic treatment is given with the help of nonsteroidal anti-inflammatory drugs and corticosteroids. Some chemotherapeutic drugs are found to be useful in improving arthritic and skin lesions. Bisphosphonates have also been found to show improvement in the affected individuals. It is advisable to use the drugs in a combination formula. The prognosis is poor for cases with multiple organ system involvements or an underlying malignant tumor.

What Is the Prognosis of Multicentric Reticulohistiocytosis?

Generally, the disease goes into remission after about eight years. By that time, the destruction of joints would have occurred to a significant range. Sometimes, individuals may have facial deformities, deformed joints, and more.

Conclusion

Multicentric reticulohistiocytosis is a rare disease with systemic involvement in advanced cases. Early diagnosis of the disease should therefore be established to prevent the disease from progressing into a debilitating state. Since the disease is often associated with a malignancy, it is critical to rule out any underlying malignancy during the diagnosis of the condition. It is aggressive in nature and requires early treatment to halt the progression of the disease.