A possible case of Erdheim-Chester Disease.

Aim: To present the case of a 57-year-old male with progressive bilateral proptosis. Material and method: The patient presented with bilateral proptosis and strength deficiency on the upper limbs. During hospitalization, the progression was unfavorable; proptosis progressed, causing a severe loss of vision in the left eye (from 0.8 Snellen to NLP). Results: The imagistic investigation revealed bilateral infiltration of the orbits, infiltrative lesions to the mediastinum and the abdomen. The patient was referred to neurosurgery for further management. Surgical orbital decompression was performed with biopsy. The histopathological examination revealed non-Hodgkin small cell lymphoma. Conclusions: Assembling the clinical and paraclinical data we have suspected the possible diagnosis of Erdheim-Chester disease, however, positive diagnosis has not been achieved.


Introduction
The Erdheim-Chester Disease (ECD) is a rare form of non Langerhans cell histiocytosis. Individuals affected by this disease are typically adults in their 5th-7th decades of life. Males and females are almost equally affected. The ECD has no known etiology, is a multisystemic disease mainly involving the bones, lungs, skin, retroorbital tissues, central nervous system (CNS), large vessel, kidneys, retroperitoneum and heart [1,2].
Neurological symptoms represent a prominent feature of ECD and occur in approximately 25%-50% of the patients at the onset or during the course of the disease. Exophthalmos, gaze disturbances, diabetes insipidus, cerebellar syndromes, seizure, and focal mass lesions-related radiculopathy are the recurrent manifestations affecting the CNS, whose lesions are directly responsible for one third of all deaths and have been specifically identified as independent predictive factors of poor prognosis [2,3].
Orbital infiltration occurs in 25% of the patients and can present as exophthalmos, oculomotor palsies. Mass effect of the retroorbital lesions might result in the thickening and Romanian Society of Ophthalmology © 2018 tortuosity of the optic nerves. The lacrimal glands and orbital muscles, as well as the retroorbital adipose tissue may be involved with the lesions [2,4].

Case report
We reported the case of a 57-year-old male with painful proptosis (approximately 3 weeks) associated with defective ocular motility, decrease of visual acuity and strength deficiency on the upper limbs.

Neurological examination
No signs of meningeal irritation, brachial diparesis with inability to raise the right arm over 90 degrees; motor shortage for prehension and fist extension, more emphasized on the globally diminished right side reflexes.

Electromyography
Does not detect significant damage to the peripheral nerves of upper limbs.
Initiation of corticotherapy with Medrol 80 mg/ daily (presumptive diagnosis of myositis), the patient's progression is unfavorable with the increase in proptosis and the marked decrease of visual acuity LE (NLP).

Thoracoabdominal CT
Infiltrative tissue lesion in the posterior median cervix, with a maximum thickness of 5.3 cm in the sagittal plane, which incorporates the descending thoracic aorta without deviating it ( Fig. 2-3). The set of lesions described may be compatible with multisystemic infiltrative lymphoma. It was decided that the patient should be urgently transferred to a university neurosurgical clinic for therapeutic management. Emergency surgical treatment was performed: bilateral orbital decompression by the orbital ceiling frontal resection, microscopic ablation of the left intraorbital formation and partial abortion of the right intraorbital formation.

Histopathological examination
Tumor proliferation consisting of diffuse atypical lymphocytes, intratumoral capillary vessels are present without obvious alterations. Final anatomopathological diagnosis: Small cell diffuse non-Hodgkin's lymphoma.

Differential Diagnosis
 Wegener lymphogranulomatosis (excluded by immunological dosages of pANCA and cANCA antibodies);  Langerhans/ non Langerhans cells (the diagnosis of certainty is performed by specific immunohistochemical stains from 2 tissue samples).

Evolution
The patient is currently under the supervision of Suceava Oncology Clinic, tetraplegic, blind (progressive decrease of visual acuity RE) under antalgic treatment (opiates).  The rapid unfavorable progression  associated  with  multisystemic  manifestation and atypical histopathology suggested a particular form of Langerhans non-Langerhans cells, Erdheim-Chester disease.  Corticotherapy changed the appearance of histiocytes by inhibiting the development.  Histopathological examination was also sent to Hôpital Pitié-Salpêtrière, Paris, France (insufficient tissue for diagnosis).

Conclusions
 Due to the small number of cases reported in literature, of which only 25% presented orbital manifestations, the symptoms could easily be included in the clinical picture of other diseases [1][2][3].  For the diagnosis of certainty, specific immunohistochemical examinations (CD 68 +, CD 163 +, Positive Factor XIIIa, Negative CD1a, Negative CD207) should be performed [2,4].