Multicentric reticulohistiocytosis

Introduction

Multicentric reticulohistiocytosis (MR) is a rare systemic granulomatous disease of unknown cause characterized by distinct histopathology. Skin, mucosa, synovia, bone and internal organs may be involved. Cutaneous nodules and distinctive arthritis, are the most prominent clinical features.[1]

Skin and Joint symptoms dominate the clinical picture. The hemispherical non tender nodules are the characteristic lesion. The nodules vary from a few millimeters to several centimeters. The face, hands, ears, forearms, scalp, neck, eye-lids, the limbs, cornea and trunk are involved in decreasing order of frequency. There is symmetric involvement of joints. The arthritis is destructive. Bone and cartilage are destroyed and severe deformation ensues. The disease progresses rapidly in the beginning, tapers and finally burns out.

Roughly half of-the patients have mucosal lesions: The lips, buccal mucosa, tongue, gingival, nasal septum, larynx and trachea are involved. The nodules mimic those in the skin.

Patients may also have systemic involvement. Myocardium, lungs, and lymphnodes may be involved.

Case Report

A 41-year-old man presented with multiple painful nodules of 3 years duration on the palms, soles, around the knee and elbow joints and the scalp. These were preceded by atleast 6-8 months by joint pains mainly of the interphalangeal, knee and ankle joints.

Cutaneous examination revealed firm, tender nodules of variable sizes predominantly on the palms and soles, a few on the dorsa of hands and larger coalesced nodules on the extensor aspects of the knee and elbow joints. A fine nodularity of the ear helices was seen and a few nodules were present on scalp. However there was no nodularity of the mucosae. Eyes showed an arcus senilis.

Systemic examination was normal. Blood investigations including specific investigations for uric acid, Rh factor and lipid profile were normal Chest X ray showed fibrosis of left apex and or irregular left superior mediastinal widening which could not be evaluated as the patient was lost tc follow up. X ray of the extremities showed articula erosions. Ultrasound abdomen and 2D echo wert normal. Histopathology revealed a diffuse infiltration with histiocytes, mono, bi and multinucleated giant cells with abundant ground glass eosinophilic cytoplasm, confirming the diagnosis of multicentric reticulohistiocytosis.

Discussion

More than 100 cases of multicentric reticulohistiocytosis have been reported in the literature since it was first described by Weber and Freudenthal.[2]

Polyarthritis is the commonest firs presenting symptom of MR. Our patient alsc presented with polyarthritis. Mittal et al have reported similar analogy in presentation in their case.[2]

Most of the skin nodules in the reportec case had the appearance of tumours which is similar to the case reported by Green et al.[2]

Our patient had no mucosal involvemen inspite of extensive skin nodular eruption. Mittal et al,[2] and Balachandran et al,[3] have reported similar absence of mucosal involvement in their case reports. However Barrow and Houlbar have reported mucosal nodules in their study of 3, cases.

The following signs have previously beer reported in multicentric reticulohistiocytosis bu were not present in our patient: Tendon sheath swelling, wrist ganglia, hyperextension of joints fractures, generalized erythema, xanthelasma lymphadenopathy, hyperlipidemia and neoplasm.