A case of bone marrow necrosis of an idiopathic aetiology: the report of a rare entity with review of the literature.

Bone Marrow Necrosis (BMN) is regarded as a rare entity in the aspirates and the trephine biopsies which are obtained from living patients and it is a rare antemortem diagnosis. Usually, BMN is associated with a poor prognosis and it has a 90% association with malignancies (mainly haematological). Its other causes include infections, drugs and other non malignant haematological causes. BMN which occurs due to unknown causes (idiopathic), is very rare. The present case report describes a case of BMN in a 14 year old male child from rural background, who came to the medicine outpatient department of a tertiary care centre in north India, with the complaints of generalized weakness, severe bone pains, especially in the ribcage area and fatigue. His peripheral blood film revealed pancytopaenia. His bone marrow aspiration yielded a watery, sero-sanguinous fluid from 2 different sites. Microscopy revealed "ghost like" haematopoietic cells lying in eosinophilic, proteinaceous material. Bone marrow biopsies from both the sites revealed extensive foci of gelatinous transformation and necrosis. A diagnosis of BMN was rendered. No underlying neoplastic / non neoplastic cause was identified, even after a thorough systematic investigation (haematological/biochemical/ radiological and immunological). Thus, a final diagnosis of BMN due to an idiopathic cause, was finally given. The patient was given supportive treatment, after which he was referred to a higher centre. BMN which arises idiopathically is usually very rare and often precedes the aetiological diagnosis and obscures the diagnosis. Traditionally, the prognoses of the patients with BMN were considered as poor, but with better treatment aids (chemotherapy and supportive treatment), the prognoses of these patients have been found to improve. Vigorous supportive care, along with a disease specific treatment, is the key to its management. This case was worth reporting, as no cause of BMN was elicited in it and we have summarized the signs and symptoms, the associations, haematological and other lab investigations and the role of radiology, which helped in its diagnosis.